JP2014156888A - Ball screw, seal material and seal structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ball screw capable of reducing slide resistance when fitting a male member to a seal material, while effectively preventing a minute foreign substance from being infiltrated between the male member and a female member.SOLUTION: The ball screw comprises: a male member 2 in which a male groove 7 is formed; a female member 3 which includes an inner peripheral surface where a female groove 12 is formed, and in which a circulation path 13 where a ball can be circulated is formed; and a seal material which is provided in axial one end portion and/or another end portion of the female member. The male member and the female member are fitted in the axial direction. The seal material 4 comprises: a fiber layer 14 including a hole 14a communicable with the inner peripheral surface of the female member 3 and a fitting surface 14b where a protrusion 14c that can be fitted with the male groove 7 is formed, and comprised of a fiber impregnated with a rubber or a resin; and a resin layer 15 which is laminated on a surface 14d opposed to the side where the hole 14a is formed, in the fiber layer 14.

Description

  The present invention relates to a ball screw used in various industrial machines, a seal material applicable to the ball screw, and a seal structure.

  Conventionally, in a ball screw device in which a ball nut is fitted to the outer periphery of a ball screw shaft, a lip seal member having a lip portion that elastically contacts the peripheral surface of the ball screw shaft is provided at the end of the ball nut. A wiper-type seal member having a cylindrical shape that fits on the outer periphery of the ball screw shaft on the outer side in the axial direction of the lip seal member, and a protrusion that fits in the thread groove of the ball screw shaft on the inner peripheral surface Is known (see Patent Document 1). In this ball screw device, the combination of the lip seal member and the wiper seal member prevents fine foreign matter from entering between the ball screw shaft and the ball nut.

  On the other hand, a sealing material formed in the same shape as the outer peripheral surface of the ball screw shaft is known (see Patent Document 2). This sealing material is provided with a thin sliding ring formed of synthetic resin on the outer peripheral surface of the ball screw shaft for the purpose of reducing sliding resistance when the ball screw shaft is fitted. It is configured by tightening the outer peripheral surface with a backup ring formed of synthetic rubber.

JP 2001-304372 A JP-A-1-275953

  However, in the ball screw device disclosed in Patent Document 1 described above, even if the intrusion of foreign matter between the ball screw shaft and the ball nut can be suppressed by the combined use of the lip type seal member and the wiper type seal member, There is a problem in that sliding resistance increases when the screw shaft is fitted to the seal member, and sliding performance is deteriorated.

  In the sealing material disclosed in Patent Document 2, since the synthetic resin is not shrinkable, it is difficult to make the sliding ring uniformly follow the outer peripheral surface of the ball screw shaft. Since the back-up ring is used for large tightening, even if synthetic resin with good slidability is used, the sliding resistance when fitting the ball screw shaft to the sealing material increases, and the slidability is reduced. There was a problem of getting worse.

  Therefore, the present invention can reduce sliding resistance when fitting the male member to the sealing material while effectively suppressing the entry of minute foreign matter between the male member and the female member. An object is to provide a ball screw, a sealing material, and a sealing structure.

(1) In the ball screw of the present invention, the male member having a plurality of male grooves capable of rolling the ball on the outer peripheral surface, and the plurality of female grooves capable of rolling the ball are opposed to the male groove. A female member having an inner peripheral surface formed and a circulation path capable of circulating the ball, and a seal member provided at one end portion and / or the other end portion in the axial direction of the female member A ball screw in which the male member and the female member are fitted in the axial direction, and the sealing material is a hole that can communicate with the inner peripheral surface of the female member; A fitting surface formed with a convex portion that can be fitted into the male groove of the male member when the male member is inserted into the hole, and at least the surface of the fitting surface is rubber or A fiber layer made of fibers impregnated with resin, and a rubber layer laminated on a surface of the fiber layer opposite to the fitting surface. It has a layer or a resin layer, and wherein the axial length of the fitting surface is the length of the following pitch width of Omizo in the male member.

  According to the configuration of (1) above, the fiber layer that fits into the male groove of the male mold member is configured by using fibers impregnated with rubber or resin, so that the fibers are firmly bonded to each other with rubber or resin. As a result, not only can the shape of the convex portion that can be fitted into the male groove of the fiber layer be maintained, but also the entry of fine foreign matter between the male fiber member and the female member can be prevented. Both problems that are in a trade-off relationship with each other, such as suppression and reduction of sliding resistance when the male member and the female member relatively move in the axial direction, can be solved simultaneously. Further, by laminating a reinforcing rubber layer or resin layer on the surface of the fiber layer opposite to the side where the holes are formed, the shape of the convex portion of the fiber layer is further stabilized, and the ball Deformation of the entire fiber layer during screw driving can be suppressed. Further, since the rubber layer or the resin layer is laminated, the fiber layer and the rubber layer or the resin layer can be stably fixed to one end or the other end of the female member. In addition, by setting the axial length of the mating surface of the sealing material to be equal to or less than the pitch width of the male groove in the male member, the rigidity of the sealing material is lowered and the flexibility of the sealing material is fully exhibited. Therefore, the followability of the fitting surface to the male member surface can be improved. Therefore, in the ball screw of the present invention, a gap is less likely to be formed between the sealing material and the male member even during operation, so that the sealing performance can be improved as compared with the conventional case.

(2) In the ball screw of the above (1), a plurality of the sealing materials are provided coaxially and continuously in series at one end portion and / or the other end portion in the axial direction of the female member. Is preferred.

  According to the configuration of (2) above, a plurality of the sealing materials of (1) are provided continuously in series in the same axis, so that the integral sealing material having the same axial length of the fitting surface as that of the configuration is provided. Rigidity is lower than. As a result, the slidability of the fitting surface is better than that of the integral sealing material. Further, since the sealing material having the configuration (2) is more easily deformed than the sealing material of the one-piece, the followability of the fitting surface of the sealing material having the first configuration to the surface of the male member is It is superior to the sealing material. Moreover, if it is the structure of said (2), the edge (end part of the side which contacts a male member) of each sealing material can scrape off the dust etc. on the male member surface. That is, according to the configuration of (2), it is possible to further suppress the intrusion of dust or the like into the ball screw as compared with the integral sealing material.

(3) In the sealing material of the present invention, the male member having a plurality of male grooves capable of rolling the ball on the outer peripheral surface, and the plurality of female grooves capable of rolling the ball are opposed to the male groove. A female member having an inner peripheral surface formed and having a circulation path through which the ball can be circulated, and a sealing material used for a ball screw fitted in an axial direction. A fitting surface formed with a hole capable of communicating with the inner peripheral surface of the mold member, and a protrusion that can be fitted into the male groove of the male member when the male member is inserted into the hole. A fiber layer comprising at least the surface of the fitting surface impregnated with rubber or resin, and a rubber layer or a resin layer laminated on a surface of the fiber layer opposite to the inner peripheral surface, The axial length of the fitting surface is equal to or shorter than the pitch width of the male groove in the male member. It characterized the door.

  According to the configuration of the above (3), the sealing material of the present invention includes a male member in which a plurality of male grooves capable of rolling a ball is formed on the outer peripheral surface, and a plurality of female grooves capable of rolling the ball. A fiber on a fitting surface on which a convex portion is formed when it is applied to a female member having an inner peripheral surface formed facing a male groove and having a circulation path through which a ball can be circulated. By configuring the layer with fibers impregnated with rubber or resin, the fibers can be firmly bonded together by rubber or resin, and as a result, the shape of the convex portion of the fiber layer can be maintained. , Suppression of the entry of fine foreign matter between the male member and the female member, and reduction of sliding resistance when the male member and the female member relatively move in the axial direction. Both issues in a trade-off relationship can be solved simultaneously. Further, by laminating a reinforcing rubber layer or resin layer for the fiber layer on the surface opposite to the side where the holes are formed in the fiber layer, the shape of the convex portion of the fiber layer is further stabilized, and the ball Deformation of the entire fiber layer during screw driving can be suppressed. Further, since the rubber layer or the resin layer is laminated, the fiber layer and the rubber layer or the resin layer can be stably fixed to one end or the other end of the female member. In addition, by setting the axial length of the mating surface of the sealing material to be equal to or less than the pitch width of the male groove in the male member, the rigidity of the sealing material is lowered and the flexibility of the sealing material is fully exhibited. Therefore, the followability of the fitting surface to the male member surface can be improved. Therefore, in the ball screw of the present invention, a gap is less likely to be formed between the sealing material and the male member even during operation, so that the sealing performance can be improved as compared with the conventional case.

(4) In the sealing material of the present invention, a plurality of the sealing materials of (3) may be provided coaxially and continuously in series.

  According to the configuration of (4) above, a plurality of the sealing materials of (3) are provided continuously in series in the same axis, so that the integral sealing material having the same axial length of the fitting surface as that of the configuration is provided. Rigidity is lower than. As a result, the slidability of the fitting surface is better than that of the integral sealing material. Further, when the configuration of (4) is applied to a ball screw, the sealing material of this configuration is more easily deformed than the integral sealing material. The followability to the male member surface is superior to that of the integral sealing material. Further, when the configuration (4) is applied to the ball screw, the edge of each sealing material (the end on the side in contact with the male member) can scrape dust on the surface of the male member. That is, according to the configuration of (4), it is possible to further suppress the intrusion of dust or the like into the ball screw as compared with the integral sealing material.

(5) In the seal structure of the present invention, the male member having a plurality of male grooves capable of rolling the ball on the outer peripheral surface and the plurality of female grooves capable of rolling the ball are opposed to the male groove. A female member having an inner peripheral surface formed and having a circulation path through which the ball can be circulated, and a seal structure applied to a ball screw fitted in an axial direction. A fitting surface formed with a hole capable of communicating with the inner peripheral surface of the mold member, and a protrusion that can be fitted into the male groove of the male member when the male member is inserted into the hole. And at least the surface of the fitting surface is made of a fiber impregnated with rubber or resin, and the axial length of the fitting surface of the male groove in the male member is The length is equal to or less than the pitch width.

  According to the configuration of (5) above, the fiber layer on the surface of the fitting surface on which the convex portion is formed is configured using fibers impregnated with rubber or resin, so that the fibers are bonded with rubber or resin. And the shape of the convex part of a fiber layer can be maintained by gathering up firmly. In addition, the suppression of the entry of fine foreign matter between the male member and the female member, and the reduction of sliding resistance when the male member and the female member relatively move in the axial direction, Both issues that are in a trade-off relationship with each other can be solved simultaneously.

(6) In the seal structure of the present invention, the seal structure of the above (5) may be configured by repeating a plurality of the coaxial seals in series.

  According to the configuration of (6) above, a plurality of the seal structures of (5) are provided continuously in series coaxially in series, so that the integral seal structure in which the axial length of the fitting surface is the same as this configuration Rigidity is lower than. As a result, the slidability of the fitting surface is better than that of the one-piece seal structure. In addition, when the configuration of (4) is applied to a ball screw, the seal structure of this configuration is more easily deformed than the integrated seal structure, so that the mating surface on the male member surface The followability is superior to that of the single-piece seal structure. Moreover, if the structure of said (4) is applied to a ball screw, the edge (end part on the side which contacts a male member) of each seal structure can scrape off the dust etc. on the surface of a male member. That is, according to the configuration of (4), it is possible to further suppress the intrusion of dust or the like into the ball screw as compared with the integral sealing material.

(A) It is an example of the perspective view which shows schematic structure of the ball screw which concerns on one Embodiment of this invention. (B) It is an example of explanatory drawing which shows the internal structure of the female type | mold member which concerns on this embodiment, and a sealing material. It is an example of the disassembled perspective view of the principal part of the ball screw which concerns on this embodiment.

  Hereinafter, a ball screw according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. In FIG. 1 (b), the sealing material 4 that is configured as a pair and does not need to be specifically distinguished and described is one sealing material 4 (the sealing material on the left side of the drawing) in order to simplify the drawing. For each of the seal materials 4 (the seal material on the right side of the paper), the symbols for the respective portions may be omitted as appropriate.

  As shown in FIGS. 1A and 1B, the ball screw 1 includes a male member 2, a female member 3, and a pair of sealing materials 4.

  The male member 2 is made of metal and has a rod-like main body 5 and a plurality of spiral male grooves 7 formed on the outer peripheral surface 6 of the main body 5 as shown in FIG. doing.

  The female member 3 is made of metal, and includes a cylindrical tubular portion 8 and a plate-like plate-like portion 9 formed at one end of the tubular portion 8 as shown in FIG. Have. Here, the cylindrical part 8 and the plate-like part 9 are integrally formed. As shown in FIG. 1B, a plurality of female grooves 12 are formed on the inner peripheral surfaces 10 and 11 of the cylindrical portion 8 and the plate-like portion 9. Each female groove 12 is formed in a spiral shape like the male groove 7 and is formed at a position facing the male groove 7 of the male member 2 as shown in FIG. Further, as shown in FIG. 1B, a circulation path 13 through which a plurality of balls B can circulate is formed inside the cylindrical portion 8. As shown in FIG. 1B, a track P that can communicate with the circulation path 13 is formed between the male groove 7 and the female groove 12. A plurality of balls B are filled in the track P.

  In the ball screw 1 of this embodiment, when the male member 2 and the female member 3 rotate relative to each other, the ball B advances while rolling on the track P, and returns to the original position via the circulation path 13. An infinite circulation path of returning is configured, and the circulation of the ball B is repeated. By such circulation of the balls B, the male member 2 and the female member 3 are relatively moved in the axial direction and can be fitted to each other. The male groove 7 of the present embodiment has a so-called four-thread structure in which the number of threads is four, and four circulation paths 13 are formed according to the number of threads.

  As shown in FIG. 1B, the sealing material 4 includes a fiber layer 14, a resin layer 15, and a cover member 16.

  The fiber layer 14 can be formed of aramid fiber, nylon, urethane, cotton, silk, hemp, acetate, rayon, fiber containing fluorine, polyester, and the like, and is impregnated with rubber or resin. The fiber shape may be, for example, a short fiber shape or a long fiber shape.

  By impregnating the fibers with rubber or resin, the rubber material or resin material enters between the fibers, and the fibers are bonded together to function as the fiber layer 14. Further, when the fibers are impregnated with rubber or the like, wear due to rubbing between the fibers is reduced, and further, the wear resistance of the surface of the fiber layer 14 generated between the fiber layer 14 and the male member 2 is increased. Can be achieved.

  In addition, the rubber | gum should just be what can impregnate a fiber. Examples of the rubber include urethane rubber, nitrile rubber, silicon rubber, fluorine rubber, acrylic rubber, ethylene-propylene rubber, butyl rubber, isoprene rubber, chlorinated polyethylene rubber, epichlorohydrin rubber, hydrogenated nitrile rubber, chloroprene rubber, Polybutadiene rubber, styrene butadiene rubber, natural rubber, or the like can be used alone, or those obtained by variously modifying these rubbers. These rubbers can be used alone or in a blend of a plurality of types of rubbers. In addition to vulcanizing agents, rubbers that have been conventionally used as rubber compounding agents, such as vulcanization accelerators, anti-aging agents, softeners, plasticizers, fillers, and coloring agents, are used in appropriate amounts. Can be blended. In addition to these, in order to improve the lubricity of the fiber layer 14, a solid lubricant such as graphite, silicon oil, fluorine powder, or molybdenum disulfide may be included in the rubber. Furthermore, instead of or together with the rubber, acrylic resin, polyester resin, urethane resin, vinyl chloride resin, polypropylene, polycarbonate, PET resin, fluororesin, polyethylene, AS resin, ABS resin, polystyrene resin, polyvinyl chloride Also, thermoplastic resins such as polyvinylidene chloride, polyvinyl acetate, nylon, alkyd resin, phenol resin, epoxy resin, polyphenylene sulfide resin, or thermosetting resin can be used.

  For the above-mentioned impregnation treatment of the fiber with rubber or resin, a method of dipping a predetermined fiber (short fiber, long fiber or cloth) after dissolving the rubber or resin with a solvent or the like to form a liquid is preferably used. . As a precursor of the fiber layer 14, a cloth in which fibers are formed in a sheet shape can be used. The method of impregnating the cloth with rubber or resin is also performed in the same manner as described above.

  Examples of what constitutes the fabric include a nonwoven fabric in which fibers are entangled irregularly, a regularly woven fabric, a knitted fabric (knit), and the like. Since these cloths are in the form of a sheet as compared with those composed only of fibers (short fibers and long fibers), they can be easily impregnated with rubber or the like (easy to handle), and further on the surface of the cover member 16. Also has the feature of being easy to adhere. For the weaving method, plain weave, satin weave, twill weave, or the like is used.

  In addition, the cloth preferably has a certain degree of elasticity. When the cloth is molded into a shape that conforms to the shape of the male groove 7, the cloth surface is easily stretchable so that the surface of the cloth follows the shape of the male groove 7, and the surface of the finished fiber layer 14 is wrinkled. There is an advantage that the surface does not easily occur and the surface is finished uniformly. As a result, the male member 2 and the sealing material 4 can be smoothly fitted. Furthermore, the sliding resistance generated between the male member 2 and the sealing material 4 can be reduced. In particular, by producing the fiber layer 14 so that the direction of the stretchability of the cloth coincides with at least the height direction of the cylindrical fiber layer 14 (the axial direction of the ball screw), the generation of wrinkles and the like described above can be achieved. This can be further suppressed.

  As shown in FIG. 2C, the fiber layer 14 is a cylindrical layer having holes 14a. And this hole 14b is connected with each internal peripheral surface 10 and 11 of the female-type member 3, as shown in FIG.1 (b). Further, as shown in FIG. 1B, the fiber layer 14 includes an inner peripheral surface (fitting surface) 14b provided at a position surrounding the hole 14a, and a convex portion 14c formed on the inner peripheral surface 14b. have. The convex portion 14c is a portion that can be fitted into the male groove 7 of the male member 2 when the male member is inserted into the hole 14a. The length of the inner peripheral surface 14b in the axial direction (the length direction of the male member 2) is the pitch width of the male groove in the male member (a thread and a screw constituting a part of the male groove in the male member 2). It is configured to have a length less than or equal to the distance to the mountain.

  The resin layer 15 is, for example, urethane rubber, nitrile rubber, silicon rubber, fluorine rubber, acrylic rubber, ethylene-propylene rubber, butyl rubber, isoprene rubber, chlorinated polyethylene rubber, epichlorohydrin rubber, hydrogenated nitrile rubber, chloroprene rubber, Polybutadiene rubber, styrene butadiene rubber, natural rubber, etc. alone or those modified in various ways, acrylic resin, polyester resin, urethane resin, vinyl chloride resin, polypropylene, polycarbonate, PET resin, fluorine resin, etc. Can be used.

  The resin layer 15 is a cylindrical layer having a hole into which the outer peripheral portion of the fiber layer 14 can be inserted, and an inner peripheral surface 14b is formed in the fiber layer 14 as shown in FIG. It is laminated on the surface 14d opposite to the side.

  It is also possible to attach a backup ring to the outer periphery of the resin layer 15. In this case, the sealing performance can be enhanced by applying an internal pressure to the inner peripheral surface 14b of the fiber layer. The backup ring has a structure in which an internal pressure can be applied to the inner peripheral surface 14b of the fiber layer, such as an O-ring or a garter spring, and it is desirable to select a type that generates an appropriate amount of internal pressure from the balance with the slidability.

  The cover member 16 is made of, for example, plastic or metal, and includes a cylindrical portion 16a, a ring portion 16b, and a ring-shaped attachment portion 16c as shown in FIG. Here, the cylindrical part 16a, the ring part 16b, and the attachment part 16c are integrally molded.

  Examples of the adhesive for bonding the fiber layer 14 or the resin layer 15 and the cover member 16 include an acrylic resin adhesive, an olefin adhesive, a urethane resin adhesive, an ethylene-vinyl acetate resin adhesive, and an epoxy resin. Adhesive, vinyl chloride resin adhesive, chloroprene rubber adhesive, cyanoacrylate adhesive, silicon adhesive, styrene-butadiene rubber adhesive, nitrile rubber adhesive, hot melt adhesive, phenol resin There are adhesives, melamine resin adhesives, urea resin adhesives, resorcinol adhesives, etc., a method of curing and adhering by applying and cooling the adhesive after it is heated and melted And a method of curing and adhering by heating the adhesive. As the surface to be bonded, for example, a contact surface between the cylindrical portion 16a of the cover member and the resin layer 15 or a contact surface between the ring portion 16b and the resin layer 15 can be considered.

  As shown in FIG. 1B, the cylindrical portion 16a is provided on a surface 15b on the opposite side of the resin layer 15 on which the fiber layer 14 is formed. As shown in FIG. 1B, the ring portion 16b is provided at one end of the cylindrical portion 16a. As shown in FIG. 1B, the ring portion 16b covers the surfaces 14e and 15d opposite to the surfaces 14e and 15c on the side where the female member 3 is formed in the fiber layer 14 and the resin layer 15. Configured.

  The attaching part 16c is provided in the other end part of the cylindrical part 16a, as shown in FIG.1 (b). The attachment portion 16c uses a fastening member (not shown) for the fiber layer 14 and the resin layer 15 covered with the members of the cylindrical portion 16a and the ring portion 16b at both ends in the axial direction of the female member 3. It is configured to be attachable.

  The shape of the cover member 16 is not limited to this shape as long as it can be attached to the end of the female member 3 in the axial direction. For example, an engraved portion is provided at the axial end of the female member 3, the fiber layer 14 and the resin layer 15 are inserted into this portion, and a plate-shaped cover member with holes and a resin layer 15 into which the male member 2 is inserted. The side surfaces may be bonded and attached to both or one of the axial ends of the female member 3 using a fastening member (not shown).

  Further, as described above, an engraved portion is provided in the axial end of the female member 3, and the fiber layer 14 and the resin layer 15 are inserted into this portion, so that the cylindrical portion 8 or the plate-like portion of the female member 3 is inserted. When a fixing screw (not shown) is driven and fixed from the outer peripheral portion 9 toward the resin layer 15, the cover member 16 may be unnecessary.

  Here, as an example of a manufacturing method of the sealing material 4, a process of forming a precursor layer of the fiber layer 14 by winding a sheet-like woven fabric impregnated with rubber or the like around the outer peripheral surface 6 of the male member 2, a sheet A step of forming a precursor layer of the resin layer 15 by winding an annular resin around the outer peripheral surface of the precursor layer of the fiber layer 14, and applying an appropriate pressure to the outer peripheral surface of the precursor layer of the resin layer 15, The process of forming the convex part 14c in the inner peripheral surface of 14 precursor layers, each precursor layer of the fiber layer 14 and the resin layer 15 is rotated in the circumferential direction of the male mold member 2, and is extracted from the male mold member 2. The process, the step of manufacturing the fiber layer 14 and the resin layer 15 by cutting the precursor layers of the fiber layer 14 and the resin layer 15 into a donut shape, the cover member 16 using an adhesive for the fiber layer 14 and the resin layer 15 The manufacturing method by performing the process of affixing one by one can be mentioned. Naturally, when the cover member is unnecessary, the step of attaching the cover member is not necessary.

(Features of the ball screw according to this embodiment)
According to the said structure, the fiber layer 14 fitted with the male groove 7 of the male member 2 is comprised using the woven fabric impregnated with rubber | gum etc., and the male member 2 and the female member 3 are comprised. Both issues that are in a trade-off relationship, such as suppressing the entry of minute foreign matter between them and reducing the sliding resistance when the male member 2 and the female member 3 move relative to each other in the axial direction Can be solved at the same time. Further, by impregnating the fiber layer 14 with rubber or the like, it is possible to improve the wearability of the surface of the fiber layer 14 generated between the fiber layer 14 and the male member 2. Further, the cover member 16 is used to laminate the fiber layer 14 on the surface 14d on the side opposite to the surface 14b where the holes 14a are formed in the fiber layer 14, thereby using the cover member 16. 14 and the resin layer 15 can be stably attached to both ends of the female mold member 3. Further, by setting the axial length of the inner peripheral surface 14 b of the sealing material 4 to a length equal to or less than the pitch width of the male groove in the male member 2, the rigidity of the sealing material 4 is lowered and the flexibility of the sealing material 4 is reduced. Therefore, the followability of the inner peripheral surface 14b to the surface of the male member 4 can be improved. Therefore, in the ball screw 1, a gap is less likely to be formed between the sealing material 4 and the male member 2 even during operation, so that the sealing performance can be improved as compared with the conventional case.

  As mentioned above, although embodiment of this invention was described based on drawing, it cannot be overemphasized that a specific structure is not limited to these embodiment. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the above-described embodiment, the example in which the pair of sealing materials 4 are attached to both ends of the female member 3 in the axial direction has been described. However, the present invention is not limited to this, and the sealing material 4 may be used depending on the use environment. It may be attached to either one of both end portions of the female member 3 in the axial direction.

  In the above embodiment, an example in which the male groove 7 of the male member 2 has a so-called four-thread structure has been described, but the present invention is not limited to this, and the number of the male grooves 7 depends on the use situation of the ball screw 1. It can be changed according to.

  In the above-described embodiment, the example in which the fibers of the fiber layer 14 are impregnated with rubber or the like has been described. However, the present invention is not limited thereto, and can be impregnated with rubber or the like and between the metal surfaces. The fiber layer 14 may be formed by using a cloth in which the fiber has a low sliding resistance. For example, canvas, velvet, denim, woven fabric, and knitted fabric impregnated with rubber or the like can be used. Moreover, you may employ | adopt the fiber which expands-contracts to the vertical / horizontal one side, or expands / contracts both to the vertical / horizontal side.

  Further, in the above embodiment, one seal material is provided at each axial end of the female member of the ball screw. However, as a modification, a plurality of seal materials are provided at either or both ends. The pieces may be provided coaxially and continuously in series. As a result, the rigidity is lower than that of the integral sealing material having the same length in the axial direction of the configuration and the mating surface, so that the slidability of the mating surface is better than that of the integral sealing material. . In addition, since the sealing material of this modification is more easily deformed than the sealing material of the one-piece, the followability of the fitting surface of the sealing material of this modification to the surface of the male member is It is superior to the material. Further, if the plurality of sealing materials are configured in series, the edge of each sealing material (the end portion on the side in contact with the male member) can scrape dust on the surface of the male member. That is, according to this modification, it is possible to further suppress the intrusion of dust and the like into the ball screw as compared with the integral sealing material.

DESCRIPTION OF SYMBOLS 1 Ball screw 2 Male member 3 Female member 4 Seal material 5 Main-body part 6 Outer peripheral surface 7 Male groove 8 Cylindrical part 9 Plate-shaped part 10, 11 Inner peripheral surface 12 Female groove 13 Circulation path 14 Fiber layer 14a Hole 14b Inside Peripheral surface (mating surface)
14c Convex part 14d-14f, 15a-15d Surface 15 Resin layer (rubber layer)
16 Cover member 16a Tubular portion 16b Ring portion 16c Mounting portion B Ball P Track

Claims (6)

A male member formed with a plurality of male grooves capable of rolling a ball on the outer peripheral surface;
A female member in which a plurality of female grooves capable of rolling the ball have an inner peripheral surface formed to face the male groove, and a circulation path capable of circulating the ball;
A sealing material provided at one end or / and the other end of the female member in the axial direction;
A ball screw in which the male member and the female member are fitted in the axial direction,
The sealing material is
A hole capable of communicating with the inner peripheral surface of the female member;
A fitting surface formed with a convex portion that can be fitted into the male groove of the male member when the male member is inserted into the hole, and at least the surface of the fitting surface is rubber or A fiber layer composed of fibers impregnated with resin;
A rubber layer or a resin layer laminated on a surface opposite to the fitting surface in the fiber layer;
Have
The ball screw characterized in that the axial length of the fitting surface is equal to or shorter than the pitch width of the male groove in the male member. At one end or / and the other end in the axial direction of the female member,
The ball screw according to claim 1, wherein the plurality of sealing materials are provided coaxially and continuously in series. A male member formed with a plurality of male grooves capable of rolling a ball on the outer peripheral surface;
A female member in which a plurality of female grooves capable of rolling the ball have an inner peripheral surface formed to face the male groove, and a circulation path capable of circulating the ball;
Is a seal material used for a ball screw fitted in the axial direction,
A hole capable of communicating with the inner peripheral surface of the female member;
A fitting surface formed with a convex portion that can be fitted into the male groove of the male member when the male member is inserted into the hole, and at least the surface of the fitting surface is rubber or A fiber layer composed of fibers impregnated with resin;
A rubber layer or a resin layer laminated on the surface opposite to the inner peripheral surface in the fiber layer;
Have
The sealing material, wherein an axial length of the fitting surface is equal to or less than a pitch width of a male groove in the male member.   A plurality of the sealing materials according to claim 3 are provided coaxially and continuously in series. A male member formed with a plurality of male grooves capable of rolling a ball on the outer peripheral surface;
A female member in which a plurality of female grooves capable of rolling the ball have an inner peripheral surface formed to face the male groove, and a circulation path capable of circulating the ball;
Is a seal structure applied to a ball screw fitted in the axial direction,
A hole capable of communicating with the inner peripheral surface of the female member;
A fitting surface formed with a convex portion that can be fitted into the male groove of the male member when the male member is inserted into the hole, and at least the surface of the fitting surface is rubber or A fiber layer composed of fibers impregnated with resin;
Have
The seal structure according to claim 1, wherein an axial length of the fitting surface is equal to or less than a pitch width of a male groove in the male member. The seal structure according to claim 5, wherein the seal structure is configured by repeating a plurality of coaxial structures continuously in series.