JP2017009077A - Side seal unit for linear motion mechanism, and linear motion mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealant for linear motion mechanism, capable of operating at low torque in linear motion with which a fine granular material having a diameter of several μm can be sealed.SOLUTION: A side seal unit 4 for linear motion mechanism seals the gap between a shaft and the front end part and rear end part of a slider, the slider linearly and reciprocatively moving on the shaft and included in a linear motion mechanism. At the front end part and rear end part of the slider, the fiber surface of a seal material comprising a fiber material is arranged so as to face the shaft side and contact along the cross sectional shape of the shaft.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a side seal unit for a linear motion mechanism and a linear motion mechanism.

  The linear motion mechanism is an element component indispensable for a mechanism that requires a linear motion positioning accuracy while reducing friction and other mechanisms that want to perform a linear motion. One of the typical mechanisms is a linear motion guide device, which is called a linear guide or an LM guide (registered trademark). This linear motion mechanism is roughly composed of two elements, a shaft and a slider. The slider is for smoothly reciprocating linearly moving on the shaft, and is in contact with the shaft inside the slider. There are "rolling elements" and "rollers". The linear motion mechanism according to the present invention having a slider and a shaft uses a linear motion guide rail having a rolling groove on a shaft having a rectangular cross section, such as a linear motion guide device (linear guide, LM guide). In addition to the conventional mechanism, a linear bushing in which the slider slides back and forth in the axial direction on the cylindrical shaft, and a spline shaft that can increase the allowable load by rolling the ball on the groove provided on the cylindrical shaft surface There is a ball spline.

  There are two types of mechanical motion: linear motion and rotational motion. It is very difficult to put the linear motion part into practical use compared to the rotational motion widely used in bearings using bearings. Met. Even if the rolling elements are used, the rolling friction coefficient is small and the starting resistance is low, the usefulness is known, but in the linear motion, it is highly rigid, labor-saving and fast, and the positioning accuracy is high. This is because it is necessary to provide a mechanism satisfying all the requirements for a mechanism having a long service life, and the required accuracy in practical use is high.

  For example, with regard to long life, it has been clarified that in the conventional linear motion mechanism, when dust or foreign matter enters the inside of the slider from the outside, the sliding property of the rolling element deteriorates and the slider life decreases. For this reason, design considerations and improvements for dust prevention have been required so that dust and foreign matter do not enter the inside of the slider.

  Therefore, in order to prevent dust and foreign matter from entering the inside of the slider, in addition to the conventional linear motion mechanism, the slider portion is provided with a slider side seal formed of a resin or elastomer material in a shape suitable for the linear motion guide rail. The thing of forming the structure which prevents the penetration | invasion of dust and a foreign material by setting it as the thing of a structure is proposed (refer patent document 1 and patent document 2).

  However, the side seals of the above-mentioned patent documents have insufficient sealing properties because the material of the lip portion that is in close contact with the linear motion guide rail in the linear motion guide device is a resin or elastomer material, and are used in a normal state. However, it was impossible to improve the sealing property so as to prevent the entry of fine particles having a diameter of about several μm. A rubber-based sealing material has high viscoelasticity and a high coefficient of friction, so it wears quickly and easily generates frictional heat. If a sponge-based sealing material is used, if a powder or the like enters the sealing material with bubbles, the sealing property is lost and it tends to be cheap. In addition, when used under severe conditions, the lip portion was broken or turned up, and there were some usage conditions such as contact with each other, resulting in a gap between the lip portion and the linear motion guide rail.

  For this reason, it is not easy to hold the sealing structure for a long period of time, and it is easy to allow the lubricant to flow out from the linear motion guide rail part and the dust and foreign matter to enter the slider during use. Since problems such as wear or damage to other mechanisms in the linear motion guide device occur, or the device stops due to malfunction or the like, maintenance work at an unexpected timing is required. Therefore, if such troubles are to be avoided in advance, frequent maintenance work of the equipment is required, and the continuous operation time of the apparatus is limited. Therefore, further improvement is strongly demanded for extending the life by dust prevention.

JP2013-122321A JP 2004-340343 A

  In the conventional side seal, in the linear motion mechanism, for example, the material of the lip portion that is in close contact with the linear motion guide rail is a resin or an elastomer material. It was extremely difficult. In addition, when used under severe conditions, the lip portion is broken or turned over, and there is a usage condition where the lip portion comes into contact with one another, resulting in a gap between the lip portion and the linear motion guide rail. As a result, the sealing mechanism cannot be maintained, and the outflow of the lubricating oil and the intrusion of dust or foreign matter into the slider are allowed.

  Therefore, the problem to be solved by the present invention is that the seal material of the side seal unit for use at both shaft end portions of the slider of the linear motion mechanism is a few μm in diameter in addition to dust and foreign matter, compared to conventional resins and elastomers. In order to be able to seal even the fine particles of a certain degree, while improving the sealing performance of the front end part and the rear end part of the slider, it also improves the followability to the shaft of the linear motion guide rail etc. However, it is to be able to operate with low torque during linear motion. The side seal unit for use in the linear motion mechanism can be easily removed from the attachment, and can be easily replaced when the seal material is worn out.

  Further, the further problem to be solved by the present invention is that even when the oil impregnated in the sealing material of the side seal unit for the linear motion mechanism runs out, a long life is ensured from there as compared to the previous one, and By ensuring a longer period before recognizing that the equipment has run out of oil, it is possible to maintain a state where dust, foreign matter and powder do not leak for a long time, effectively preventing malfunctions and damage to the equipment, and In the unlikely event that oil breaks out, the distance to the shaft of the linear motion guide rail that can maintain the sealing performance is increased, preventing malfunction and damage of the device due to the intrusion of dust, foreign matter, and fine particles with a diameter of several μm However, it is necessary to ensure a sufficient time margin from the replacement of the sealing material to the oil replenishment by the maintenance work.

  The first means of the present invention for solving the above-mentioned problem is that the shaft provided at the front end portion and the rear end portion of the slider of the linear motion mechanism comprising a shaft and a slider that linearly reciprocates on the shaft; A side seal unit for sealing a gap between the slider and a front end portion and a rear end portion of the slider with a fiber surface of a sealing material made of a fiber material facing the shaft side along the cross-sectional shape of the shaft It is a side seal unit for a linear motion mechanism, characterized in that it is arranged so that it can be swung.

  The second means is that the sealing material made of a fiber material uses a cut pile, and the cut pile is directed further toward the inner surface side from the ground yarn portion of the cut pile fixed to the inner surface side of the base. 2. The side seal unit for a linear motion mechanism according to claim 1, wherein the side seal unit is a cut pile in which a tip of a wrinkle of pile fiber floated is cut and raised. If the base is made of metal, it can be bent in accordance with the casing shapes at both ends of the shaft and the slider, so that the adhesion is easily obtained.

  The third means is that the ground yarn portion of the cut pile has a warp double weave structure consisting of two layers of a surface warp and a surface layer of the front weft, and a lining warp and a back layer portion of the back weft. The side seal unit for a linear motion mechanism according to claim 2, wherein the pile fiber is locked to the back weft. Note that the s type of the cut pile in the examples described later corresponds to an example of the third means.

  The fourth means is that the ground yarn portion of the cut pile is formed with a surface layer portion so that the surface warp yarn (a) and the surface warp yarn (b) alternately cross the surface weft yarn, and the lining warp yarn (c) Pile fabric that has a double weft structure in which the back layer portion is formed so that the back and back warp yarns (d) cross alternately with the back weft yarn, and is locked to the back weft yarn Consists of two types of fiber materials (e) and (f), wherein the pile fibers (e) and the pile fibers (f) are alternately locked to adjacent back wefts, A side seal unit for a linear motion mechanism according to claim 2. In addition, the t type of the cut pile in the below-described embodiments corresponds to an example of the fourth means.

  The fifth means is the side seal unit for a linear motion mechanism according to claim 1, wherein the sealing material made of a fiber material is made of a felt-like non-woven fabric.

  6. The linear motion according to claim 1, wherein the sixth means is a wet sealing material in which the sealing material made of a fiber material holds a lubricant between the fibers. 6. This is a mechanism side seal unit.

  The seventh means is a linear motion mechanism comprising the linear motion mechanism side seal unit according to any one of claims 1 to 6.

  The seal material of the side seal unit for linear motion mechanism of the present invention uses a seal material made of a fiber material on the shaft or linear motion guide rail contact surface, so that it can be compared with a resin or elastomer of a lip part material of a conventional side seal. The effect of improving followability to the shaft (linear motion guide rail) can be obtained. As a result, in addition to dust and foreign matter, the effect of enabling sealing of fine particles having a diameter of about several μm can be obtained.

  In addition, since it is a fiber material, it is easy to hold a sufficient amount of lubricant between the fibers, and it keeps the sealing property long by bleeding between the slider each time the slider slides back and forth. Can do.

  Further, since the sealing material of the present invention is configured to be easily attached and detached by attaching to the front end portion and the rear end portion of the slider, it can be easily removed from the slider and replaced, and the sealing material is worn out by any chance. In some cases, it can be easily replaced.

  And even if the oil of the lubricant impregnated in the sealing material of the side seal unit for the linear motion guide device runs out of the present invention, at least 4 to 5 times to about 1000 times as compared with the conventional one. A long life can be secured. As a result, the user can ensure a longer period until the device runs out of oil, and during that time, dust, foreign matter and powder will not leak, effectively preventing malfunctions and damage to the device. In addition, by performing a replacement operation of the sealing material and replenishing the lubricant with oil during the maintenance operation, it is possible to effectively prevent malfunctions and breakage of the apparatus over a long period of time.

  In the cut pile, since the tip is cut and raised, the fibers spread radially toward the tip. Therefore, it is easy to hold the oil component of the lubricant between the fibers of the cut pile. Moreover, since the fiber spreads and there is no gap, it is difficult for the fine particles to enter the inside, and a higher dustproof effect can be obtained. In addition, around the weft that fixes and supports the cut pile, the cut pile tends to form a part that does not spread radially, and the cut pile near the root near the ground part has a gap around the tip compared to the tip. Cheap. Therefore, since the surface layer portion and the lower layer portion of the background double weave have a thickness, the gap between them is filled with these ground yarn portions. Therefore, since the ground yarn portion has a thickness, it is difficult for a gap to occur in the raised cut pile root portion.

It is the perspective view which showed embodiment of this invention to the structure of the linear guide apparatus as an example. It is the front view which looked at the linear guide apparatus of FIG. 1 from the axial direction. It is AA sectional drawing of FIG. It is a front view of the attachment of the side seal unit for linear motion mechanisms. It is a front view of the sealing material of the side seal unit for linear motion mechanisms. It is a figure explaining the outline | summary of the linear motion guide apparatus used for evaluation. It is a schematic diagram which shows the fabric structure around the ground yarn part of the cut pile of a shaft seal (s type). It is the figure which showed the sealing member 4b of the cut pile applied to a linear bush from the side surface. It is a schematic diagram which shows the fabric structure around the ground yarn part of the cut pile of a shaft seal (t type). It is the perspective view which showed the structure of the linear bush which shows the 3rd Embodiment of this invention.

  DESCRIPTION OF EMBODIMENTS Embodiments of a linear motion mechanism side seal unit and a linear motion mechanism according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is based on a linear guide device using a conventional steel spherical rolling element (which will be described below as an example of a linear motion mechanism using a linear motion guide device (LM guide) manufactured by NSK Ltd.). FIG. 2 is a perspective view showing the structure of the first embodiment of the present invention, in a state in which the linear seal device 4 for a linear motion mechanism according to the present invention is newly mounted on the conventional linear guide device. In addition, in each figure after this, the same code | symbol is attached | subjected to the part corresponded to the same figure.

  On a linear motion guide rail 1 that is a shaft extending in the axial direction, a slider 2 having a shape covering the linear motion guide rail 1 (for example, a U-shaped slider) is relatively movable in the axial direction of the linear motion guide rail 1. It is assembled. Rolling element rolling grooves 6b and 6b formed of 1/4 arc-shaped concave grooves are formed at ridges where the upper surface 1b of the linear guide rail 1 intersects the left and right side surfaces 1a and 1a. Rolling element rolling grooves 6a, 6a formed of ½ arc-shaped concave grooves are formed at intermediate positions in the vertical direction of the left and right side surfaces 1a, 1a of the rail 1.

  The slider 2 is composed of a slider body 2a and end caps 2b and 2b that are detachably attached to both ends in the axial direction. Further, a linear motion guide rail is provided at the end of the end cap 2b. Rubber side seals 3, 3 for sealing the side surfaces 1a, 1a of the linear motion guide rail 1 and the openings 1b of the linear motion guide rail 1 and the end caps 2b, 2b in the gap between the slider 1 and the slider 2. Is installed. The rubber side seals 3 and 3 are elastomeric seals applied to a conventional linear motion guide device. Even if oil is applied, the frictional resistance is high, so that the adhesion tends to decrease due to wear.

  Therefore, in the first embodiment of the present invention, in addition to the side seals 3 and 3 of the front end portion and the rear end portion, side seal units 4 and 4 for linear motion mechanisms made of a fiber material are used as follows. I have. First, using the through holes provided for the left and right screws of the side seals 3 and 3 to pass, the side seal units 4 and 4 for the linear motion mechanism are respectively attached to the front end portion and the rear end portion of the slider. Yes. The linear motion mechanism side seal unit 4 is composed of two parts including an attachment 4a and a sealing material 4b. These sealing materials 4b are made of, for example, cut piles, hold oil between the fibers of the cut piles, and even the fine particles having a diameter of about several μm are linear motion guide rails 1 And the slider 2 can be prevented from entering, and the sealing performance is higher than that of the side seal 3.

  In the lower corners of the inner side surfaces of the left and right side surfaces 5 and 5 of the slider main body 2a and the central portion in the vertical direction, the ½ arc-shaped rolling element rolling grooves 6a, 6a and ¼ arc of the linear motion guide rail 1 are provided. Opposing rolling element rolling grooves 6b, 6b having a shape are formed, rolling element rolling grooves 7a, 7a having a substantially ½ arc shape in cross section, and rolling element rolling grooves 7b, 7b having a ¼ arc shape are formed. Yes. Then, the 1/2 arc-shaped rolling element rolling grooves 6a and 6a of the linear motion guide rail 1, the 1/4 arc-shaped rolling element rolling grooves 6b and 6b, and the 1/2 arc-shaped rolling groove of the slider body 2a. Four sets of rolling element rolling paths 8, 8, 8, 8 having a substantially circular cross section are formed by facing the rolling element rolling grooves 7a, 7a and the ¼ arc-shaped rolling element rolling grooves 7b, 7b. Is done. These four sets of rolling element rolling paths 8 extend in the axial direction. Note that the 1/2 arc-shaped rolling element rolling groove 6a, the 1/4 arc-shaped rolling element rolling groove 6b, and the 1/2 arc-shaped rolling element rolling groove 7a included in the linear motion guide rail 1 and the slider 2 are provided. The ¼ arc-shaped rolling element rolling groove 7b is not limited to two rows on one side.

  Further, the slider 2 has four straight paths 9 formed of holes penetrating in the axial direction in parallel with the rolling element rolling paths 8 at the upper and lower portions of the thick portions of the left and right side surfaces 5 and 5 of the slider body 2a. , 9, 9, 9 are provided.

  The end cap 2b is made of an injection molded product of a resin material and has a cross-sectional shape that covers the linear motion guide rail 1. As shown in the sectional view of FIG. 3, the end caps 2b and 2b on both ends of the slider 2 have rolling element rolling paths 8 and 8 on the left and right sides of the contact surface (back surface) with the slider body 2a. It has a semi-doughnut-shaped curved path 10 that passes through parallel straight paths 9 and 9. The straight path 9 and the curved paths 10 and 10 at both ends form a rolling element return path 11 that feeds and circulates the rolling element 12 from the end point of the rolling element rolling path 8 to the starting point, and this rolling element return path 11. And the rolling element rolling path 8 form a rolling element circulation path. In this rolling element circulation path, spherical rolling elements 12 are loaded so as to be freely rotatable, and along the linear motion guide rail 1 in which the slider 2 is a shaft through the rolling of these rolling elements 12, It moves in the axial direction.

  When the slider 2 assembled to the linear motion guide rail 1 is moved along the linear motion guide rail 1 in the axial direction, the rolling element 12 loaded in the rolling element rolling path 8 becomes the rolling element rolling path. It moves in the direction opposite to the slider 2 with respect to the linear motion guide rail 1 while rolling in 8. When the rolling element 12 reaches the end point of the rolling element rolling path 8, the rolling element 12 is sent to the curved path 10. The steel spherical rolling element 12 that has entered the curved path 10 is U-turned and introduced into the straight path 9, and reaches the curved path 10 on the opposite side through the straight path 9. Here, the U-turn is performed again to return to the starting point of the rolling element rolling path 8, and such circulation is repeated infinitely.

  Here, the side seal unit 4 for the linear motion mechanism will be described in detail. The linear seal mechanism side seal unit 4 includes two parts, an attachment 4a and a seal material 4b. FIG. 4 is a front view of the attachment 4a, and FIG. 5 is a front view of the sealing material 4b. A state in which the seal member 4b is attached to the attachment 4a and the side seal unit 4 for the linear motion mechanism is formed is as shown in FIG. Among the gaps between the linear motion guide rail 1 and the slider 2, to seal the opening portions of the side surfaces 1a, 1a of the linear motion guide rail 1, the upper surface 1b of the linear motion guide rail 1, and the end cap 2b of the slider 2. The sealing material 4b is formed in a shape that matches the shape of the linear motion guide rail 1. The fiber sealing material 14 having a shape following the bending of the exterior material 13 is bent by the exterior material 13 (base 18) of the seal material 4b, and the clearance between the linear motion guide rail 1 and the slider 2 on the linear motion guide rail 1 Is sealed. The shape of the sealing material 4b is not particularly limited, and can be appropriately changed depending on the shapes of the linear motion guide rail 1 and the slider 2. In the present embodiment, the side surfaces 1a, 1a of the linear motion guide rail 1, the ¼ arc-shaped rolling element rolling grooves 6a, 6a of the left and right ridge lines of the upper surface 1b of the linear motion guide rail 1, and the linear motion Since the rolling rail rolling grooves 6b, 6b on the left and right half arcs of the guide rail 1 are recessed, the corresponding portions of the seal material are refracted so as to be slidable in contact therewith.

  In the conventional side seal 3, the contact surface with the linear motion guide rail 1 is made of a resin or an elastomer material, and a gap is generated due to the influence of the mounting accuracy, the lip contact surface being bent or peeled off during use, and fine dust. Or, it was not suitable for sealing foreign matter. Further, depending on the use situation, a piece-of-piece contact may occur, which is the same result as described above. Thus, the conventional example has a difficulty in sealing performance.

  On the other hand, the sealing material 4b of the present invention is a fiber sealing material 14, and can follow the shape of the sliding contact surface by applying a certain load on the characteristics of the fiber, Further, by adjusting the diameter and density of the fiber, it is possible to sufficiently seal an extremely fine powder fluid having a diameter of several μm. Specifically, it consists of a cut pile in which 1 denier polyester fiber is locked at a density of 660,000 per square inch on the weft of the woven fabric of the ground yarn portion. Specifically, the pile fiber 24 of the cut pile is, for example, a polyester fiber, and has a diameter of about 10 μm. Therefore, the pile fiber 24 is extremely thin and is densely and densely raised. Since it is received as a surface, the intrusion of fine particles can be pushed away by a large number of piles and can be sufficiently eliminated without yielding pressure. In addition, since the lubricant oil can be sufficiently held in the gap between adjacent piles, the lubricant oil can be supplied between the shafts each time the slider slides. The degree can be easily maintained. Further, the sealing material 4b has a ground yarn portion bonded and fixed to one surface of a metal base 18, and a pile is raised from the weft of the ground yarn. Reference numeral 18 denotes an exterior material 13 that is bent and bent while the metal is plastically deformed and bent so as to follow the inner wall surface side of the casing of the sealing material 4b. Since the base 18 is made of metal, at the time of manufacturing the pile material, a cut pile fabric is bonded on a flat metal plate and then cut into a desired size to obtain a sealing material. By bending in accordance with the shape on the spot, the sealant 4b can be used detachably.

  Now, in the conventional side seal 3, when it was worn out, the slider 2 had to be disassembled and replaced. On the other hand, since the seal member 4b of the side seal unit 4 for the linear motion mechanism of the present invention is only fitted from the outside after the attachment 4a is fixed to the end cap 2b, it can be easily removed and replaced. Therefore, it is highly maintainable and highly convenient when used for a long time.

  Unlike the first embodiment, the second embodiment is a linear seal mechanism side seal unit used for a linear motion mechanism used in a linear motion guide device using a roller-shaped rolling element made of steel as a rolling element. Yes (not shown). The structure and operation of the linear motion guide device according to the second embodiment are such that the rolling element is not a steel ball but a roller made of steel, and the rolling element raceway surface is not a circular groove but a plane. Except for, it is the same as the first embodiment. Accordingly, the sealing material of the side seal unit for the linear motion guide device has a shape corresponding to this, and the attachment has a shape to which the sealing material can be attached.

  The third embodiment is a linear bush 17 in which a slider linearly moves in the axial direction of a cylindrical shaft having a diameter of 16 mm as a linear motion mechanism, and the inner periphery of the front end portion and rear end portion of the casing of the cylindrical slider 2 The seal material 4b of the ring-shaped linear motion mechanism side seal unit 4 is fitted to the surface. The metal base 18 has a C-shape that is almost circular and has a notch in a part of the circumference. When the notch is reduced, the outer diameter is slightly reduced like a spring by a spring back, and then a linear bush. The sealing material 4b can be fitted into the 17 inner walls of the casing. That is, since the outer diameter of the base 18 is slightly larger than the inner diameter of both ends of the casing of the linear bush 17, it fits firmly in the casing inner surface. Now, on the inner surface side of the base 18, there is a ground yarn portion 19 for fixing the raised pile fiber 24.

  Hereinafter, the present invention will be specifically described by the description of examples, but the present invention is not construed as being limited by the description.

  In the conventional linear motion guide device, a seal material made of nitrile rubber is attached so that dust and foreign matter do not enter the inside of the slider, but there is a possibility that fine powder may enter. Therefore, it is clear that if dust or foreign matter enters the inside of the slider from the outside, the sliding property of the rolling element deteriorates and the life of the slider is reduced.

  Therefore, the seal performance of the linear bush 17 alone attached to the conventional linear motion guide device and the shaft seal by the side seal unit 4 for the linear motion mechanism of the present invention are applied to the front end portion and the rear end portion of the slider 2 of the linear bush 17. A test was conducted to compare the sealing performance with the case of attachment.

<Test Example 1: Confirmation of seal performance of seal unit for linear motion guide device>
In this test, the sealing performance in the case of using the side seal unit of the present invention attached to the conventional linear motion guide device as a wet type in which oil is supplied in order to enhance the slidability and in the case of using it as a dry type without oil supply, Comparison was made with the sealing performance of the linear bushing alone attached to the linear motion guide device.

<Materials and methods>
FIG. 6 shows an outline of the linear motion guide device used for the evaluation. Table 1 shows a list of LM shafts, shaft seals, and powders used in the evaluation.

  Since metal powder such as metal powder and cutting powder resulting from the friction of equipment is hard and has sharp edges, if it leaks into the end cap, various metal members including linear motion guide rails etc. A member made of sealing material resin, rubber, or the like constituting the end cap is damaged and becomes a factor that hinders stable operation of the linear motion guide device. Therefore, iron powder having an average particle size of 30 μm was selected as model particles for reproducing hard fine particles such as metal powder generated from friction of such equipment and metal powder such as cutting powder. In addition, in order to examine the sealing properties in a state where fine powder such as dust, which is finer than the fine particles, is generated and present in the equipment use environment, as model particles to reproduce fine powder having an average particle size of about 5 μm, A magenta toner that is a classified colored functional fine particle was selected.

  A rubber seal material, which is a conventional end cap, is attached to the end portion of the linear bushing of the apparatus. Therefore, in this test, an example in which a shaft seal using a sealing material made of the fiber material of the present invention is further used on the outside of the end cap is used as an example, and a conventional usage mode without a side seal unit (no sealing material) Was set as a comparative example, and the sealing performance was evaluated. As an example of the shaft seal using the sealing material made of the fiber material of the present invention, five types of shaft seals made of pile fabrics having different materials, shapes, and pile lengths were selected and used for the test.

  The details of the t-type and s-type shaft seals are shown in Table 2. First, in the s type, the raised pile fiber 24 is one type of polyester fiber, the ground yarn portion 19 is a woven fabric of weft yarn (polyester) and warp yarn (nylon 66 / nylon 6), and two layers of a surface layer portion and a back layer portion The background is made of double weaving. The cut pile is a pile fiber 24 of 1.0 denier (about 10 μm diameter) polyester fiber, and the density is 660,000 per square inch.

  Among the sealing materials, the t type has two types of raised pile fibers 24 and is alternately fixed to the wefts of the ground yarn portion 19 one by one. Pile 1 is a blend of 3.0 denier acrylic, 1.5 denier acrylic and 1.5 denier rayon, and pile 2 is made of 0.5 denier polyester fiber. The density of the fibers is about 6460,000 per square inch. The ground yarn portion 19 for fixing the cut pile is a woven fabric of weft yarn (polyester) and warp yarn (polyester / rayon), which is a warp double weave consisting of two layers, a surface layer portion and a back layer portion. All the pile fibers are coated with an acrylic emulsion on the surface, and have a lower coefficient of friction.

  As shown in FIGS. 7 and 8, the pile fabric used for the shaft seal is a pile floated from the ground yarn portion of the cut pile fixed to the inner surface side of the metal base toward the inner surface side. It is a pile fabric made of cut piles that are obtained by cutting and raising the tips of the fibers of the fiber. The cut pile base yarns are the surface layer portions of the surface warp yarn and the surface weft yarn, and the back layer portion of the lining warp yarn and the back weft yarn. The pile fiber is locked to the back weft.

  Table 3 shows a list of various sealing materials attached to the linear bush.

  In the above apparatus, the oil is supplied to the linear bush, and the oil that is used as it is is oiled, and the oil that is wiped from the linear bush or the oil that does not use the linear bush is oil-free. In addition, the powders used for leakage evaluation were two types: carrier only and toner only. The linear motion distance was set to 10 cm for one reciprocation.

  Then, two linear bushes were passed through the LM shaft, and a portion where the shaft directly touched the powder was provided to perform a linear motion, and evaluation was performed using only the linear bush, the pile length of the shaft seal, and the presence or absence of oil. The shaft seal was attached between the powder and the linear bush, and the total travel distance was calculated from the number of reciprocations when leakage occurred. The larger the numerical value, the better the sealing performance.

<Result>
The powder sealability was evaluated as described above. The results are shown in Table 4.

  As a result of the test, it was confirmed that a fine powder having a very small particle diameter such as toner has no sealing effect when there is no sealing material (Comparative Example 6).

  However, when the shaft seal of the present invention is used, a high sealing effect that is not obtained with the conventional structure is confirmed (Examples 1 to 5), and the pile length is controlled. Thus, it was confirmed that an extremely high sealing effect of 1000 times or more was observed under severe conditions such as no oil.

  Furthermore, even for iron powder of about 30μ such as a carrier, the invention of the present invention controls the pile length in a severe condition where there is no oil, so that it is five times that of the conventional structure. It was confirmed that it was possible to ensure a high lifetime (about each example).

  Therefore, in the example using the iron powder in the condition of no oil, when the travel distance by the linear motion reaches 10 km, that is, when no leakage occurs as shown in Table 3 above, the shaft Replacing the seal with a new one, replenishing the oil, and resuming the linear motion showed that no leakage occurred until it reached the same distance as the oil.

  Generally, the durability of the linear bush in the absence of oil or grease is about 470 km in terms of the total travel distance. From this test result, if there are many powders such as carriers in the atmosphere of the environment in which the equipment is used, the life that the linear bush should originally have will be shortened to 1/100 or less, However, it has been confirmed this time that if the shaft seal of the present invention is used, the life that should be shortened to 1/100 or less may be extended by 4 to 5 times.

  Also, the linear bush life is likely to be reduced in a severe environment where there are many fine powders consisting of extremely fine particles such as toner in the atmosphere of the environment in which the equipment is used, but the shaft seal of the present invention is used. As a result, it was confirmed that a decrease in the life of the linear bushing was suppressed, and that a significant life extension effect could be expected up to about 1000 times that of the conventional one.

  Equipment that uses a linear bush is normally used with oil in order to extend the life of the linear bush. However, when used for a long time, oil runs out. Therefore, it is necessary to regularly maintain and replenish oil to maintain the condition.

  However, there is a case where maintenance is not always performed at a predetermined time. In this case, maintenance is delayed and oil runs out. And if oil runs out even once, the conventional one has a very short life after the oil has run out, as confirmed in the above test. Or damage will occur. In addition, even if the oil runs out by the time of normal maintenance due to some trouble and the user cannot recognize the oil shortage, the conventional product has a life after running out of oil. Since it is extremely short, the powder leaks, resulting in malfunction or damage to the equipment.

  However, as has been clarified in the above test, even if oil runs out due to the use of the shaft seal of the present invention for the linear motion guide device, it is at least 4 as compared with the conventional one. A long life of about 5 to 1000 times is secured. As a result, the user can ensure a longer period until the device runs out of oil, and the powder does not leak during that time, effectively preventing malfunctions and damage to the device. Furthermore, it has become clear that, during that time, the shaft seal is replaced and the oil is replenished by maintenance work, so that malfunctions and breakage of the apparatus can be effectively prevented over a long period of time.

<Test Example 2: Measurement of moving torque>
In this test, the moving torque of the linear bush when various sealing materials were attached was measured. Even if the sealing material of the present invention is used, it is confirmed that there is no increase in moving torque that hinders the operation of the apparatus.

<Materials and methods>
The same equipment and sealing material as in Test Example 1 were used. A shaft seal and a linear bush were attached under the same conditions as in the evaluation of sealability. With the shaft inserted, the evaluator was fixed to the measuring part of the digital force gauge, the evaluator was pulled, and the torque at the moment of starting to move was recorded.

<Result>
The moving torque was evaluated as described above. The results are shown in Table 5.

In the condition with the seal material using the shaft seal of the embodiment, the torque value is slightly increased as compared with the state without the seal material. However, as long as the pile length is not too long, there is no problem in using the device. It turned out to remain in value. And it is thought that about 2.5 mm is suitable as a pile length. Moreover, it was possible to suppress the increase in torque to a lower level by appropriately selecting the type of the sealing material.
As described above, it was found that, by further mounting the shaft seal of the present invention on the linear bushing of the linear motion guide device, even in an environment where a large number of fine powders exist, a low torque and a long life can be secured. .

DESCRIPTION OF SYMBOLS 1 Linear motion guide rail 1a Side surface (of linear motion guide rail 1) 1b Upper surface (of linear motion guide rail 1) 2 Slider 2a Slider body 2b End cap 3 Side seal 4 Side seal unit for linear motion mechanism 4a Attachment 4b Seal material 5 Left and right side surfaces of the slider body 6a Rolling element rolling groove of linear motion guide rail (1/2 arc shape of linear motion guide rail 1) 6b Linear motion guide rail (1/4 arc shape of linear motion guide rail 1) Rolling element rolling groove 7a rolling element rolling groove 7b of slider body (slider ½ arc shape) 7b rolling element rolling groove 8b of slider body (slider ¼ arc shape) 8 rolling element rolling Moving path 9 Straight path 10 Curved path 11 Rolling element return path 12 (steel ball) rolling element 13 Exterior material 14 Fiber seal material 15 LM shaft 16 Shaft seal 17 Linear bush 18 Pedestal 19 ground yarn portion 20 Outer warps 21 Table weft 22 lining the warp 23 back weft 24 pile fibers

Claims (7)

  A side seal unit for sealing a gap between the shaft and the shaft provided at a front end portion and a rear end portion of a linear motion mechanism including a slider that linearly reciprocates on the shaft, A side seal unit for a linear motion mechanism, characterized in that a fiber surface of a sealing material made of a fiber material is arranged at the front end portion and the rear end portion so as to abut on the shaft side along the cross-sectional shape of the shaft. .   The sealing material made of a fiber material uses a cut pile, and the cut pile is a ring of pile fibers floated further toward the inner surface from the ground yarn portion of the cut pile fixed to the inner surface of the base. The side seal unit for a linear motion mechanism according to claim 1, wherein the side seal unit is a cut pile in which a tip of a hook is cut and raised.   The ground portion of the cut pile is a double weft structure consisting of a surface layer portion of a surface warp and a surface weft, and a back layer portion of a lining warp and a back weft, and the pile fiber is related to the back weft. The side seal unit for a linear motion mechanism according to claim 2, wherein the side seal unit is stopped.   The cut pile ground yarn portion is formed such that the surface warp yarn (a) and the surface warp yarn (b) are alternately intersected with the surface weft yarn interposed therebetween, and the lining warp yarn (c) and the lining warp yarn (d) A double weft weft structure with back layers formed so as to cross each other alternately with back weft yarns. The pile fibers locked to the back weft yarns are made of two types of fiber materials ( 3. The straight fiber according to claim 2, wherein the pile fiber (e) and the pile fiber (f) are alternately locked to adjacent back weft yarns. Side seal unit for moving mechanism.   The side seal unit for a linear motion mechanism according to claim 1, wherein the sealing material made of a fiber material is made of a felt-like non-woven fabric.   The side seal unit for a linear motion mechanism according to any one of claims 1 to 5, wherein the seal material made of a fiber material is a wet seal material in which a lubricant is held between fibers.   The linear motion mechanism provided with the side seal unit for linear motion mechanisms of any one of Claims 1-6.

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