HK1237019B - Linear motion bearing composite with housing - Google Patents

Description

Linear motion bearing complex with housing

Technical Field

The present invention relates to a housing-mounted linear motion bearing complex, and more particularly, to a housing-mounted linear motion bearing complex in which a plurality of linear motion bearings are arranged in a predetermined positional relationship and integrated with a housing.

Background Art

Linear motion bearings (linear bearings) are mechanical components that support the shaft body inserted into the bearing and realize smooth movement of the shaft body in the linear direction (i.e., axial direction) as a driving force is applied along the axial direction of the shaft body. They are installed in various mechanical devices for use.

Linear motion bearings typically consist of an outer cylinder, a cylindrical rolling element retainer fitted inside the outer cylinder, and multiple rolling elements, such as balls, held within the cylindrical rolling element retainer. A shaft is inserted into the inner side of the cylindrical rolling element retainer and slidably supported by the rolling elements, which partially protrude from the inner side of the cylindrical rolling element retainer. Therefore, if an axial driving force is applied to the shaft, it can move smoothly in a linear direction in response to this driving force.

In order to facilitate the incorporation of linear motion bearings into various mechanical devices, there are known linear motion bearings with a housing in which a cylindrical housing made of metal or resin is arranged around an outer cylinder of the linear motion bearing.

Figures 1(a) and 1(b) are, respectively, a perspective view showing an example of the structure of a conventionally used housing linear motion bearing and a cross-sectional view of the housing linear motion bearing 10 taken along the line II-II indicated in Figure 1(a). However, Figure 1(b) shows the shaft 21 inserted into the housing linear motion bearing 10. Figure 1(b) shows the bottom side (the side with the threaded hole 15c) of the housing 15 shown in Figure 1(a) on the left side (illustration of the threaded hole 15c is omitted).

The housing-mounted linear motion bearing 10 shown in Figures 1(a) and 1(b) consists of an outer cylinder 11, a cylindrical rolling element retainer 12 fitted inside the outer cylinder 11, a linear motion bearing 14 including a plurality of rolling elements 13 retained by the cylindrical rolling element retainer 12, and a cylindrical housing 15 disposed around the linear motion bearing 14. The housing 15 is formed of a metal or resin material and has threaded holes 15c for mounting (installation) into various mechanical devices.

Furthermore, in such a housinged linear motion bearing, a means for fixing the linear motion bearing inside the housing is generally provided to prevent the linear motion bearing from being separated from the housing due to axial movement of the shaft (ie, linear motion).

Specifically, in the housinged linear motion bearing 10 shown in Figures 1(a) and 1(b), a retaining ring (snapping ring) 16 is provided on either axially outer side of the linear motion bearing 14 to prevent it from being separated from the housing 15. The retaining ring 16 is fitted into a circumferential groove 17 formed by cutting the inner circumferential surface of the housing 15.

Patent Document 1 describes a housing-mounted linear motion bearing as shown in Figures 1(a) and 1(b). In the housing-mounted linear motion bearing described in Patent Document 1, the housing is formed of a resin material, and threaded holes are formed on the outer circumference of the housing for mounting to various machines.

Furthermore, this document describes that in order to prevent the linear motion bearing from being separated from the housing, the housing and the linear motion bearing are fixed to each other by bonding, press-fitting, or a retaining ring.

Prior art literature

Patent Literature

Patent Document 1: Japanese Patent Application Laid-Open No. 2010-133489.

Summary of the Invention

Problems to be solved by the invention

Although there are cases where only one housing linear motion bearing is installed in a mechanical device, in order to achieve high-precision linear motion of the shaft body, two or more housing linear motion bearings are often arranged in series. That is, by inserting the shaft body into two or more housing linear motion bearings arranged in series and causing it to move linearly, high-precision linear motion of the shaft body is achieved. Alternatively, sometimes two or more linear motion bearings are arranged in parallel and installed in a mechanical device, and the shaft bodies are arranged in parallel and inserted into each housing linear motion bearing, so that two or more shaft bodies can move linearly in parallel with each other. Moreover, sometimes two or more housing linear motion bearings are arranged in a mutually intersecting manner, and the shaft bodies inserted into each housing linear motion bearing are moved linearly in mutually intersecting directions.

When arranging multiple linear motion bearings with housings in a series, parallel, or interdigitated arrangement and fixing their positional relationships, a method typically involves preparing a base plate, placing the multiple linear motion bearings at predetermined positions on the base plate, and securing them to the base plate using threaded holes provided in each bearing. However, arranging and securing multiple linear motion bearings with housings on the base plate with high precision requires skilled skill, and the arranging and securing operations are also complex. Therefore, it is not easy to manufacture multiple base plates that can be used to secure multiple linear motion bearings with housings in a series, parallel, or interdigitated arrangement.

Therefore, an object of the present invention is to provide a linear motion bearing complex in which a plurality of linear motion bearings that can be manufactured without requiring special skills are arranged and fixed in series, in parallel, or in a mutually crossed state.

Solutions for solving problems

The present invention is a linear motion bearing complex with a housing, which is constructed by arranging two or more linear motion bearings each including an outer cylinder, a cylindrical rolling element retainer embedded in the inner side of the outer cylinder, and a plurality of rolling elements retained by the cylindrical rolling element retainer in parallel, series, or mutually crossed arrangements, and then integrally forming a covering layer made of a resin material around the outer cylinder of each linear motion bearing, thereby fixing each linear motion bearing in a housing formed by the covering layer.

Preferred embodiments of the housing-equipped linear motion bearing composite of the present invention are described below.

(1) The configuration of two or more linear motion bearings is in parallel or series.

(2) Two or more linear motion bearings are arranged in series to form a linear motion bearing complex column, and then the linear motion bearing complex column and one linear motion bearing are combined to form two or more columns and arranged in parallel, and a covering layer made of a resin material is integrally formed around the outer cylinder of each linear motion bearing, thereby fixing each linear motion bearing in a housing formed by the covering layer.

(3) Arranging two or more linear motion bearings in series to form a linear motion bearing complex array, and then after combining and arranging the two or more linear motion bearing complex arrays in parallel, integrally forming a resin material covering layer around the outer cylinder of each linear motion bearing, thereby fixing each linear motion bearing in a housing formed by the covering layer

(4) Two or more linear motion bearings are arranged in series to form a linear motion bearing complex array, and then after the linear motion bearing complex array and one linear motion bearing are arranged in a mutually crossed arrangement and combination, a covering layer made of a resin material is integrally formed around the outer cylinder of each linear motion bearing, thereby fixing each linear motion bearing in a housing formed by the covering layer.

(5) Two or more linear motion bearings are arranged in series to form a linear motion bearing complex column, and then after the two or more linear motion bearing complex columns are arranged in a mutually crossed arrangement and combination, a covering layer made of a resin material is integrally formed around the outer cylinder of each linear motion bearing, thereby fixing each linear motion bearing in a housing formed by the covering layer.

(6) Each linear motion bearing is arranged in a metal mold, and then the periphery of the outer cylinder of each linear motion bearing is integrally covered with a resin material, which is hardened to form a covering layer, thereby fixing each linear motion bearing in a housing formed by the covering layer.

(7) The covering layer formed around each linear motion bearing extends beyond each of the end faces of the outer cylinder of the linear motion bearing and covers at least a portion of each end face.

(8) The covering layer covers at least the outer peripheral areas of both end surfaces of the outer cylinder of the linear motion bearing.

(9) A convex portion is provided on one of a surface of a covering layer formed around each linear motion bearing that contacts the outer peripheral surface of an outer cylinder of the linear motion bearing and an outer peripheral surface of the outer cylinder of the linear motion bearing, and a concave portion is provided on the other.

(10) A recess is provided on the outer peripheral surface of the outer cylinder of each linear motion bearing, and a convex portion is provided on the surface of the covering layer formed around the linear motion bearing that contacts the outer peripheral surface of the outer cylinder of the linear motion bearing.

Effects of the Invention

The housing-mounted linear motion bearing complex of the present invention is a housing-mounted linear motion bearing complex that can be easily manufactured by using a pre-prepared metal mold for casting a resin material, after arranging a plurality of linear motion bearings in parallel, series, or in a cross-arranged arrangement at predetermined positions within the metal mold, injecting a liquid thermoplastic resin material or a thermosetting resin material into the metal mold, thereby covering the periphery of the plurality of linear motion bearings with the resin material, and then subjecting the housing-mounted linear motion bearing complex to a cooling process or a curing process. Therefore, the housing-mounted linear motion bearing complex of the present invention can be manufactured without requiring particularly skilled techniques. In addition, in the housing-mounted linear motion bearing complex of the present invention, a plurality of linear motion bearings with housings are arranged in parallel, series, or in a cross-arranged arrangement, and are fixed in a highly precise positional relationship.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a perspective view showing an example of the structure of a conventional housing-mounted linear motion bearing, and also a cross-sectional view of the housing-mounted linear motion bearing taken along line II-II. However, in the cross-sectional view, the bottom side of housing 15 (the side having threaded hole 15c) is shown on the left side (illustration of threaded hole 15c is omitted).

Figure 2 is a diagram showing an example of the structure of a linear motion bearing complex with a housing of the present invention (a linear motion bearing complex with a housing in which two linear motion bearings are arranged in parallel), (a) is a stereoscopic diagram, (b) is a cross-sectional diagram cut in a vertical direction relative to each linear motion bearing, and (c) is a cross-sectional diagram cut in an axial direction of the linear motion bearing.

Fig. 3 is a diagram showing a preferred configuration example of each housing linear motion bearing incorporated into the housing linear motion bearing composite of the present invention. (a) is a cross-sectional view cut along the axial direction, and (b) is a partial enlarged view of (a).

Fig. 4 is a diagram showing another preferred configuration example of each housing linear motion bearing incorporated into the housing linear motion bearing composite of the present invention. (a) is a cross-sectional view cut along the axial direction, and (b) is a partial enlarged view of (a).

Figure 5 is a diagram showing an example of the structure of a linear motion bearing complex with a housing of the present invention (a linear motion bearing complex with a housing in which two linear motion bearings are arranged in series), (a) is a three-dimensional diagram, and (b) shows a cross-sectional view of each linear motion bearing cut in the axial direction, and (c) shows a cross-sectional view cut in the vertical direction relative to the linear motion bearing.

Figure 6 is a diagram showing an example of the structure of a linear motion bearing complex with a housing of the present invention (a linear motion bearing complex with a housing having two groups of linear motion bearings arranged in parallel with each other in a row of linear motion bearings arranged in series), (a) is a three-dimensional diagram, and (b) shows a cross-sectional view of each linear motion bearing cut in the axial direction, and (c) shows a cross-sectional view cut in the vertical direction relative to the linear motion bearing.

Figure 7 is a diagram showing an example of the structure of a linear motion bearing complex with a housing of the present invention (a linear motion bearing complex with a housing in which two linear motion bearings are arranged in series and two groups of linear motion bearings are arranged in parallel with each other, and furthermore, two linear motion bearings are arranged in series and two groups of linear motion bearings are arranged in parallel with each other, and the whole is integrated through a base plate). In the linear motion bearing complex with a housing, with respect to each linear motion bearing, (a) is a three-dimensional view, and (b) shows a cross-sectional view of one group of linear motion bearings cut along the axial direction, and (c) shows a cross-sectional view of another group of linear motion bearings cut along the axial direction.

Figure 8 is a diagram showing an example of the structure of a linear motion bearing complex with a housing of the present invention (a linear motion bearing complex with a housing in which two linear motion bearings are arranged in series and two groups of linear motion bearings are arranged in parallel with each other, and furthermore, two linear motion bearings are arranged in series and two groups of linear motion bearings are arranged in parallel with each other, and the whole is integrated through a substrate).

Figure 9 is a diagram showing another structural example of the shell linear motion bearing complex of the present invention (a shell linear motion bearing complex in which two linear motion bearings are arranged cross-wise at right angles to each other), (a) is a three-dimensional diagram, and (b) shows a cross-sectional view of one linear motion bearing cut along the axial direction, and (c) shows a cross-sectional view of the other linear motion bearing cut along the axial direction.

Figure 10 is a diagram showing another configuration example of the linear motion bearing complex with a housing of the present invention (a linear motion bearing complex with a housing in which two linear motion bearings are arranged in series and the linear motion bearing rows are arranged at right angles to each other), (a) is a stereoscopic diagram, and (b) shows a cross-sectional view of one linear motion bearing cut along the axial direction, and (c) shows a cross-sectional view of another linear motion bearing cut along the axial direction.

DETAILED DESCRIPTION

First, a typical embodiment of a housing-equipped linear motion bearing according to the present invention will be described with reference to the drawings.

FIG2 is a diagram showing an example of the structure of a housing linear motion bearing complex of the present invention (a housing linear motion bearing complex in which two linear motion bearings are arranged in parallel), (a) is a perspective view, (b) is a cross-sectional view cut in a perpendicular direction relative to each linear motion bearing, and (c) is a cross-sectional view cut in an axial direction of the linear motion bearing. In the housing linear motion bearing complex 30 of the present invention shown in FIG2 , two linear motion bearings 14 are arranged in parallel with each other and are housed in a housing 35 formed around the outer cylinder of each linear motion bearing so as to be integrated. In addition, in the structure of FIG2 , "two linear motion bearings are arranged in parallel" includes not only a structure in which two linear motion bearings are arranged in a strictly parallel relationship, but also a structure in which two linear motion bearings are arranged in a roughly parallel relationship.

In Figure 2, the two linear motion bearings 14 included in the shell linear motion bearing complex 30 can also be the linear motion bearings used in the previous shell linear motion bearing as shown in Figure 1, that is, a linear motion bearing including an outer cylinder 11, a cylindrical rolling element retainer 12 embedded in the inner side of the outer cylinder 11, and a plurality of rolling elements (such as balls) 13 retained by the cylindrical rolling element retainer 12.

However, the structure of the housing 35 formed around the outer cylinder 11 of the linear bearing 14 included in the housinged linear bearing composite 30 of the present invention is preferably any of the structures shown in FIG. 3 and FIG. 4 .

FIG3(a) and FIG3(b) are a cross-sectional view and a partially enlarged view, respectively, illustrating the preferred relationship between each linear motion bearing 14 and the housing 35 formed therearound in the housinged linear motion bearing complex 30 of the present invention. FIG3(a) is shown with the axial direction vertical to facilitate comparison with FIG1(b).

The housing-mounted linear motion bearing complex 30 shown in FIG. 3( a ) is composed of an outer cylinder 11, a cylindrical rolling element retainer 12 fitted inside the outer cylinder 11, a linear motion bearing 14 including a plurality of rolling elements 13 retained by the cylindrical rolling element retainer 12, and a cylindrical housing 35 disposed around the linear motion bearing 14. The structure of the linear motion bearing 14 used is essentially the same as that of the conventional housing-mounted linear motion bearing 10 shown in FIG. 1( a ) and ( b ). Furthermore, the housing-mounted linear motion bearing of the present invention shown in FIG. 3 is generally provided with a means for securing the linear motion bearing within the housing 35 to prevent it from detaching due to axial movement (i.e., linear motion) of the shaft 21. Specifically, as with the housinged linear motion bearings shown in Figures 1(a) and 1(b), retaining rings (snapping rings) 16 are provided on either axial outer side of the linear motion bearing 14 to prevent it from being separated from the housing 35. The retaining rings 16 are fitted into circumferential grooves formed by cutting the inner circumferential surface of the housing 35.

The housing 35 of the housinged linear motion bearing assembly 30 shown in FIG3(a) is a cured resin material. As shown in the enlarged view in FIG3(b), both ends of the housing 35 (the ends corresponding to the ends of the linear motion bearing) extend beyond the respective end faces of the outer cylinder 11 and cover an annular region on the outer circumference of each end face (a portion of each end face of the outer cylinder). In the following description, the portion of the housing 35a covering a portion of the outer cylinder end face is also referred to as the "covering portion."

The housing 35 can be molded from a liquid resin material in a mold using a known method, and can be formed simply and directly around the linear motion bearing 14. Therefore, the inner surface of the housing 35 is formed in a shape corresponding to the outer shape of the outer cylinder 11.

As previously described, in the housing-mounted linear motion bearing assembly 30 shown in Figure 3(a), the covering portion 35a of the housing 35 partially covers each end surface of the outer cylinder 11. Consequently, the outer cylinder 11 of the linear motion bearing 14 cannot move axially relative to the housing 35. Specifically, the housing 35 formed as described above simultaneously prevents the linear motion bearing 14 from moving axially, or in other words, from falling out (detaching) from the housing. Consequently, the complex work of securing the linear motion bearing 14 and the housing 35 to each other using separately prepared securing means is eliminated.

Thus, the housing-attached linear motion bearing complex 30 shown in FIG. 3( a ) can be easily manufactured.

FIG4(a) and FIG4(b) are a cross-sectional view and a partially enlarged view, respectively, illustrating another preferred relationship between each linear motion bearing 14 and the housing 55 formed therearound in the housinged linear motion bearing complex 50 of the present invention. FIG4(a) is also shown with the axial direction vertical to facilitate comparison with FIG1(b).

The housing-mounted linear motion bearing complex 50 shown in FIG. 4( a ) also comprises the following components: an outer cylinder 51; a cylindrical rolling element retainer 12 fitted inside the outer cylinder 51; a linear motion bearing 54 comprising a plurality of rolling elements 13 retained by the cylindrical rolling element retainer 12; and a housing 55 disposed around the linear motion bearing 54. The structure of this linear motion bearing 54 is essentially the same as that of the linear motion bearing 14 of the conventional housing-mounted linear motion bearing 10 shown in FIG. 1( a ) and ( b ). Furthermore, the housing-mounted linear motion bearing of the present invention shown in FIG. 4 is also generally provided with a means for securing the linear motion bearing within the housing 55 to prevent it from detaching due to axial movement (i.e., linear motion) of the shaft 21. That is, similar to the housinged linear motion bearing shown in Figures 1(a) and 1(b), as a means of securing the linear motion bearing 54 so that it does not separate from the housing 55, retaining rings (snapping rings) 16 are provided on both outer sides in the axial direction of the linear motion bearing 54. The retaining rings 16 are fitted into circumferential grooves formed by cutting the inner circumferential surface of the housing 55.

However, the housing linear motion bearing complex 50 shown in FIG. 4( a ) has a recess 51 a provided on the outer circumferential surface of the outer cylinder 51 and a convex portion 55 a provided on the inner circumferential surface of the housing 55 as shown in FIG. 4( b ).

The housing 55 in FIG. 4( a ) can also be formed simply and directly around the linear motion bearing 54 by molding a resin material using a known method.

In the housing-mounted linear motion bearing assembly 50 shown in FIG4(a), the recessed portion 51a of the outer cylinder 51 and the protruding portion 55a of the housing 55 engage with each other. Consequently, the outer cylinder 51 of the linear motion bearing 54 cannot move axially relative to the housing 55. Specifically, when the housing 55 is formed as described above, a means is also provided to prevent the linear motion bearing 54 from moving axially, i.e., from falling out (detaching) from the housing 55. Consequently, the complex work of securing the linear motion bearing 54 and the housing 55 to each other using separately prepared securing means is unnecessary.

FIG5 illustrates another example of the housing-mounted linear motion bearing complex of the present invention (a housing-mounted linear motion bearing complex in which two linear motion bearings are arranged in series). FIG5(a) shows a perspective view, while FIG5(b) and FIG5(c) are cross-sectional views of the housing-mounted linear motion bearing complex shown in FIG5 along the axial direction and along a direction perpendicular to the axial direction, respectively. In the housing-mounted linear motion bearing complex 60 of the present invention shown in FIG5 , two linear motion bearings 14 are arranged and fixed in series.

In Figure 5, the two linear motion bearings 14 included in the shell linear motion bearing complex 60 can also be the linear motion bearings used in the previous shell linear motion bearing as shown in Figure 1, that is, the linear motion bearing 14 includes an outer cylinder 11, a cylindrical rolling element retainer 12 embedded in the inner side of the outer cylinder 11, and a plurality of rolling elements 13 retained by the cylindrical rolling element retainer 12.

However, the housing 65 formed around the outer cylinder 11 of the linear motion bearing 14 included in the housinged linear motion bearing complex 60 of FIG. 5 is preferably any one of the structures shown in each of FIG. 3 and FIG. 4 .

FIG6 is a diagram showing another example of the structure of the housing linear motion bearing complex of the present invention (a housing linear motion bearing complex in which two linear motion bearings are arranged in series and two groups of linear motion bearings are arranged in parallel with each other), (a) in FIG6 shows a stereoscopic view, (b) and (c) are a cross-sectional view along the axial direction and a cross-sectional view along a direction perpendicular to the axial direction of the housing linear motion bearing complex shown in (a), respectively. In the housing linear motion bearing complex 70 of the present invention shown in FIG6, two linear motion bearings 14 arranged and fixed in a series relationship are arranged and fixed in two rows in a parallel relationship. In addition, instead of the housing linear motion bearing complex in which two linear motion bearings are arranged in series and two groups of linear motion bearings are arranged in parallel with each other as shown in FIG6, a linear motion bearing complex column and a linear motion bearing can also be combined and arranged in parallel with each other.

In Figure 6, the four linear motion bearings 14 included in the shell linear motion bearing complex 70 can also be the linear motion bearings used in the previous shell linear motion bearing as shown in Figure 1, that is, the linear motion bearings 14 include an outer cylinder 11, a cylindrical rolling element retainer 12 embedded in the inner side of the outer cylinder 11, and a plurality of rolling elements 13 retained by the cylindrical rolling element retainer 12.

However, the housing 75 formed around the outer cylinder 11 of the linear bearing 14 included in the housinged linear bearing complex 70 of FIG. 6 is preferably any of the structures shown in each of FIG. 3 and FIG. 4 .

FIG7 shows another example of the housing-mounted linear motion bearing complex of the present invention (a housing-mounted linear motion bearing complex in which two linear motion bearings are arranged in series, two linear motion bearing rows are arranged in parallel, and two linear motion bearing rows are arranged in parallel, and the entire structure is integrated via a base plate). FIG7 (a) is a perspective view, and FIG7 (b) and FIG7 (c) are cross-sectional views of one linear motion bearing row and another linear motion bearing row, respectively, in the axial direction of the housing-mounted linear motion bearing complex shown in FIG7. In the housing-mounted linear motion bearing complex 80 of the present invention shown in FIG7, the rows of two linear motion bearings 14 arranged and fixed in series comprise four rows, and each row of two rows is similarly arranged and fixed in parallel, facing each other, on an integrally formed resin base plate 86.

In Figure 7, the four linear motion bearings 14 included in the shell linear motion bearing complex 80 can also be the linear motion bearings used in the previous shell linear motion bearing as shown in Figure 1, that is, the linear motion bearings 14 include an outer cylinder 11, a cylindrical rolling element retainer 12 embedded in the inner side of the outer cylinder 11, and a plurality of rolling elements 13 retained by the cylindrical rolling element retainer 12.

However, the housing 85 formed around the outer cylinder 11 of the linear bearing 14 included in the housinged linear bearing complex 80 of FIG. 7 is preferably any of the structures shown in each of FIG. 3 and FIG. 4 .

FIG8 is a perspective view showing another example of the structure of a housing-mounted linear motion bearing complex according to the present invention. In the housing-mounted linear motion bearing complex 90 according to the present invention shown in FIG8 , the two linear motion bearings arranged in series have four rows, and the two rows are fixed in parallel facing each other. However, in the housing-mounted linear motion bearing complex 90 of FIG8 , the housing-mounted linear motion bearing row 91 is composed of the linear motion bearings in series, each of which is integrally connected to the housing base plate 96, and the housing-mounted linear motion bearing row 92 is fixed to the base plate by screw fastening. The former has two rows of housing-mounted linear motion bearings, and the latter has two rows of housing-mounted linear motion bearings, which are similarly fixed in series facing each other on the base plate 96 made of resin material.

In Figure 8, the four linear motion bearings 14 that constitute the shell linear motion bearing complex 90 can also be the linear motion bearings used in the previous shell linear motion bearing as shown in Figure 1, that is, the linear motion bearing 14 includes an outer cylinder 11, a cylindrical rolling element retainer 12 embedded in the inner side of the outer cylinder 11, and a plurality of rolling elements 13 retained by the cylindrical rolling element retainer 12.

However, the housing formed around the outer cylinder of the linear motion bearing included in the housinged linear motion bearing complex 90 of FIG. 8 is preferably any of the structures shown in each of FIG. 3 and FIG. 4 .

FIG9 illustrates another example of the housing-mounted linear bearing complex of the present invention (a housing-mounted linear bearing complex in which two linear bearings are arranged orthogonally (intersecting at right angles) to each other). (a) is a perspective view, (b) is a cross-sectional view of one linear bearing taken along the axial direction, and (c) is a cross-sectional view of the other linear bearing taken along the axial direction. In the housing-mounted linear bearing complex 100 of the present invention shown in FIG9 , two linear bearings 14 are arranged in parallel and housed within a housing 105 formed around the outer cylinder of each linear bearing, thereby forming an integrated structure.

In Figure 9, the two linear motion bearings 14 included in the shell linear motion bearing complex 100 can also be the linear motion bearings used in the previous shell linear motion bearing as shown in Figure 1, that is, a linear motion bearing including an outer cylinder 11, a cylindrical rolling element retainer 12 embedded in the inner side of the outer cylinder 11, and a plurality of rolling elements 13 retained by the cylindrical rolling element retainer 12.

However, the structure of the housing 105 formed around the outer cylinder 11 of the linear bearing 14 included in the housinged linear bearing complex 100 of FIG. 9 is preferably any of the structures shown in FIG. 3 and FIG. 4 .

FIG10 illustrates another example of the housing-mounted linear motion bearing complex of the present invention (a housing-mounted linear motion bearing complex in which two linear motion bearings are arranged in series, forming a linear motion bearing row, and the linear motion bearing rows are arranged orthogonally (at right angles) to each other). (a) is a perspective view, (b) is a cross-sectional view of one linear motion bearing cut along the axial direction, and (c) is a cross-sectional view of the other linear motion bearing cut along the axial direction. In the housing-mounted linear motion bearing complex 110 of the present invention shown in FIG10 , two rows of linear motion bearings 14 arranged and fixed in series are provided, and are housed and fixed orthogonally to each other within a housing 115. Alternatively, instead of the housing-mounted linear motion bearing complex shown in FIG10 , in which two linear motion bearing rows are arranged in a cross-mounted relationship, a combination of linear motion bearing rows and a linear motion bearing can be arranged in a cross-mounted arrangement.

In Figure 10, the four linear motion bearings 14 included in the shell linear motion bearing complex 110 can also be the linear motion bearings used in the previous shell linear motion bearing as shown in Figure 1, that is, a linear motion bearing including an outer cylinder 11, a cylindrical rolling element retainer 12 embedded in the inner side of the outer cylinder 11, and a plurality of rolling elements 13 retained by the cylindrical rolling element retainer 12.

However, the housing 115 formed around the outer cylinder 11 of the linear bearing 14 included in the housinged linear bearing complex 110 of FIG. 10 is preferably any of the structures shown in each of FIG. 3 and FIG. 4 .

Next, a method for forming a cured resin body around a plurality of linear motion bearings arranged in series, in parallel, or crosswise with each other will be described.

The housing can be formed of a known resin material. As the resin material, preferably a thermoplastic resin material or various curable resin materials are used, and a thermoplastic resin is particularly preferably used.

Examples of thermoplastic resins include polyacetal resins, polyphenylene sulfide (PPS) resins, polyamide resins, and polyetheretherketone (PEEK) resins. The thermoplastic resin may be a reinforced thermoplastic resin containing a reinforcing material such as glass fiber.

The method for forming the housing is not particularly limited, and a method suitable for the resin material used can be used. The housing is preferably formed by injection molding or casting. Furthermore, when multiple linear motion bearings are fixed in a predetermined position within a mold, for example, when multiple linear motion bearings are arranged in series, a method can be employed in which each linear motion bearing is arranged around a shaft to form the housing, and then the shaft is removed.

In the case of a housing with covering portions covering both ends of the outer cylinder of the linear bearing, as in the housinged linear motion bearing assembly 30 shown in FIG3 , the covering portions only need to cover at least a portion of each end surface of the outer cylinder. The covering portions may cover only a portion of the circumferential direction of each end surface of the outer cylinder, or only a portion of the radial direction of each end surface of the outer cylinder, for example, an annular region on the outer circumference of each end surface of the outer cylinder, as shown in FIG3 and FIG4 , or may cover the entire portion (the entirety) of each end surface of the outer cylinder.

The covering portion may protrude further inward than the inner peripheral edge of the outer tube, and may be closer to the peripheral surface of the shaft body as long as it does not hinder smooth movement of the shaft body within the linear motion bearing.

The housing-attached linear motion bearing having the housing having the above-described covering portion can be produced (manufactured) by, for example, a method including the following steps.

The method includes: a step of covering the inner circumferential surfaces of a plurality of outer cylinders (outer cylinders of linear motion bearings) with a shielding member, arranging them at predetermined positions, and then arranging a metal mold around the outer cylinders; a step of causing a resin material in a fluid state (for example, a thermoplastic resin material that is heated and molten) to flow into the metal mold and cover the linear motion bearings, and then solidifying the resin material to form a shell around the above-mentioned outer cylinders, wherein the portions of the shell that contact the two end portions of the outer cylinders of the linear motion bearings extend beyond the end faces of the outer cylinders and cover at least a portion of each end face; a step of removing the metal mold and the shielding member from the outer cylinder and the shell; and a step of fitting a cylindrical rolling element retainer that retains a plurality of rolling elements into the inner side of the outer cylinder.

In the housing-mounted linear motion bearing complex 50 shown in FIG4 , a recess 51a is provided on the outer circumferential surface of the outer cylinder 51, and a projection 55a is provided on the inner circumferential surface of the housing 55. Alternatively, the outer cylinder may have a projection on its outer circumferential surface, while the housing may have a recess on its inner circumferential surface. Furthermore, multiple sets of these projections and recesses may be provided.

However, when the outer cylinder is formed of a metal material such as steel, it is easier to manufacture the outer cylinder having recesses on the outer peripheral surface than the outer cylinder having projections on the outer peripheral surface by simple machining.

The recessed portion includes a groove extending in the circumferential direction of the outer cylinder or shell. The groove may be formed in a portion of the circumferential direction of the outer cylinder or shell, or may be formed in the entire circumferential direction (thus forming an annular shape). Similarly, the raised portion includes a linear protrusion extending in the circumferential direction of the outer cylinder or shell. The linear protrusion may be formed in a portion of the outer cylinder or shell, or may be formed in the entire circumferential direction (thus forming an annular shape).

The housing-attached linear motion bearing complex having recessed portions on the outer circumferential surface of the outer cylinder and projecting portions on the inner circumferential surface of the housing can be produced (manufactured) by, for example, a method including the following steps.

The method includes: a process of covering the inner circumference of a plurality of outer cylinders (outer cylinders of linear motion bearings) having recesses on their outer circumferences with a shielding member, arranging them at predetermined positions, and then arranging a metal mold around the outer cylinder; a process of causing a resin material in a flowing state (for example, a thermoplastic resin material that is heated and melted) to flow into the metal mold and then solidifying it, thereby forming a shell around the above-mentioned outer cylinder, but forming a convex portion on the inner circumference of the shell that fits into the recessed portion of the above-mentioned outer cylinder (engages with the recessed portion of the outer cylinder); a process of removing the metal mold and the shielding member from the outer cylinder and the shell; and a process of fitting a cylindrical rolling element retainer that holds a plurality of rolling elements into the inner side of the outer cylinder.

Similarly, a linear motion bearing with a housing having a convex portion on the outer peripheral surface of the outer cylinder and a concave portion on the inner peripheral surface of the housing can be produced (manufactured) by a method including the following steps, for example.

The method includes: a process of covering the inner circumference of a plurality of outer cylinders (outer cylinders of linear motion bearings) having convex portions on their outer circumferences with a shielding member, arranging them at predetermined positions, and then arranging a metal mold around the outer cylinder; a process of causing a resin material in a flowing state (for example, a thermoplastic resin material that is heated and melted) to flow into the metal mold and then solidifying it, thereby forming a shell around the above-mentioned outer cylinder, but forming a recess on the inner circumference of the shell that is engaged with the convex portion of the above-mentioned outer cylinder (engaged with the convex portion of the outer cylinder); a process of removing the metal mold and the shielding member from the outer cylinder and the shell; and a process of engaging a cylindrical rolling element retainer that holds a plurality of rolling elements inside the outer cylinder.

As the linear motion bearing housed in the housing, a known linear motion bearing comprising an outer cylinder, a cylindrical rolling element retainer fitted inside the outer cylinder, and a plurality of rolling elements retained by the cylindrical rolling element retainer can be used. Known linear motion bearings include endless circulation type linear motion bearings and non-endless circulation type linear motion bearings, but either type may be used.

As an infinite circulation linear motion bearing, a cylindrical rolling element retainer is formed with a rolling element circulation groove, which accommodates multiple rolling elements. This allows the rolling elements to circulate around the shaft, thus achieving unlimited movement of the supporting shaft.

In non-infinite-circulation linear motion bearings, multiple through-holes are formed in the wall of a cylindrical rolling element retainer to rotatably accommodate and retain individual rolling elements. The rolling elements are housed in each of these through-holes. This allows the multiple rolling elements supporting the shaft to move axially along with the cylindrical rolling element retainer. The shaft's travel distance is typically limited to a distance that prevents the cylindrical rolling element retainer from protruding from the end opening of the outer cylinder during shaft movement.

As the shaft body supported by the linear motion bearing, a shaft body with a circular cross section or a shaft body with a plurality of linear grooves spaced apart from each other in the circumferential direction (also called a spline shaft) can be listed. As the shaft body, a hollow shaft body can also be used.

The outer cylinder is formed of a metal material such as steel (eg, stainless steel) or a resin material. In addition, when the housing linear motion bearing is used in water or a high-temperature environment, the outer cylinder can also be formed of a ceramic material.

The cylindrical rolling element retainer is formed of, for example, a metal material or a resin material. Examples of the resin material include polyacetal resin, polyphenylene sulfide (PPS) resin, polyamide resin, and polyetheretherketone (PEEK) resin.

The cylindrical rolling element retainer can be produced by molding the resin material using various molding methods (for example, injection molding, compression molding, or casting).

The rolling element is formed of a metal material such as steel (e.g., stainless steel), but may also be formed of a resin material. In addition, when the housing linear motion bearing is used in water or at a high temperature, the rolling element may also be formed of a ceramic material.

Examples of rolling elements include spherical bodies (balls) and rollers (columnar bodies whose cross sections perpendicular to the central axis are circular).

In the linear motion bearing, for example, as can be seen from the linear motion bearing 14 shown in FIG. 1 , a stopper ring (snag ring) 16 may be further provided to prevent the cylindrical rolling element retainer 12 from being detached (falling off) from the outer cylinder 11 .

As a method of preventing the cylindrical rolling element retainer from being separated (falling off) from the outer cylinder, a known method can be used instead of the above-mentioned method of arranging the stopper ring.

Explanation of symbols

10 Linear motion bearings with housing

11 outer cylinder

12 Cylindrical rolling element retainer

13 rolling elements

14 Linear motion bearings

15 Housing

15c Threaded hole for mounting

16 retaining ring

17 Circumferential groove

21 axis

30 Linear motion bearing complex with housing

35 housing

35a Covering part

50 linear motion bearing complex with housing

51 outer cylinder

51a recess

54 linear motion bearings

55 housing

55a convex part

60, 70, 80, 90, 100, 110 linear motion bearing complex with housing

65, 75, 85, 105, 115 shells.

Claims (11)

1. A composite linear motion bearing with a housing, comprising two or more linear motion bearings, each including an outer cylinder, a cylindrical rolling element retainer fitted inside the outer cylinder, and multiple rolling elements held by the cylindrical rolling element retainer, arranged in parallel, series, or cross configurations, wherein a resin material covering layer is integrally formed around the outer cylinder of each linear motion bearing, thereby fixing each linear motion bearing within a housing formed by the covering layer, wherein the two or more linear motion bearings arranged in a cross configuration are fixed by continuously and integrally forming a resin material covering layer around the outer cylinder of each linear motion bearing. 2. The linear motion bearing composite with housing according to claim 1, characterized in that the configuration of two or more linear motion bearings is in parallel or in series. 3. The linear motion bearing composite with housing according to claim 1, characterized in that it is constructed by arranging two or more linear motion bearings in series to form a linear motion bearing composite array, and then combining the linear motion bearing composite array with a linear motion bearing to form two or more arrays and arranging them in parallel, and integrally forming a resin material covering layer around the outer cylinder of each linear motion bearing, thereby fixing each linear motion bearing in the housing formed by the covering layer. 4. The linear motion bearing composite with housing according to claim 1, characterized in that it is constructed by arranging two or more linear motion bearings in series to form a linear motion bearing composite array, and then combining and arranging two or more of the linear motion bearing composite arrays in parallel, thereby integrally forming a resin material covering layer around the outer cylinder of each linear motion bearing, thereby fixing each linear motion bearing in the housing formed by the covering layer. 5. The linear motion bearing composite with housing according to claim 1, characterized in that it is composed of two or more linear motion bearings arranged in series to form a linear motion bearing composite array, and after the linear motion bearing composite array and a linear motion bearing are arranged in a mutually intersecting combination, a resin material covering layer is integrally formed around the outer cylinder of each linear motion bearing, thereby fixing each linear motion bearing in the housing formed by the covering layer. 6. The linear motion bearing composite with housing according to claim 1, characterized in that it is constructed by arranging two or more linear motion bearings in series to form a linear motion bearing composite array, and then arranging two or more arrays of the linear motion bearing composite in a mutually intersecting arrangement, thereby integrally forming a resin material covering layer around the outer cylinder of each linear motion bearing, thereby fixing each linear motion bearing in the housing formed by the covering layer. 7. The linear motion bearing composite with housing according to claim 1, characterized in that it is constructed by placing each linear motion bearing in a metal mold, then integrally covering the outer cylinder of each linear motion bearing with resin material, hardening it to form a covering layer, thereby fixing each linear motion bearing in a housing formed by the covering layer. 8. The housing-type linear motion bearing composite according to claim 1, characterized in that the covering layer formed around each linear motion bearing extends beyond each of the two end faces of the outer cylinder of the linear motion bearing and covers at least a portion of each end face. 9. The linear motion bearing composite with housing according to claim 8, characterized in that the covering layer covers at least the outer peripheral regions of both end faces of the outer cylinder of the linear motion bearing. 10. The linear motion bearing composite with housing according to claim 1, characterized in that one of the surfaces of the covering layer formed around each linear motion bearing that are in contact with the outer peripheral surface of the outer cylinder of the linear motion bearing and the outer peripheral surface of the outer cylinder of the linear motion bearing is provided with a protrusion, and the other is provided with a recess. 11. The linear motion bearing composite with housing according to claim 10, characterized in that a recess is provided on the outer peripheral surface of the outer cylinder of each linear motion bearing, and a protrusion is provided on the surface of the covering layer formed around the linear motion bearing that is in contact with the outer peripheral surface of the outer cylinder of the linear motion bearing.