JP2005155702A - Ball screw lubrication seal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a contact oil supply capable of stably supplying a lubricant for a long period of time while eliminating the complexity of a lubrication mechanism and capable of absorbing and retaining a larger amount of lubricant, and also having a sealing function. Also provided is a so-called externally-attached ball screw lubrication seal device which is attached to a standard ball screw nut and attached later.
SOLUTION: A substantially cylindrical case body having attachment portions to both ends of a screw nut and a hole corresponding to a cross-sectional shape perpendicular to the axis of a screw groove of a ball screw shaft, and being shifted in the circumferential direction and superposed. A plurality of thin plate seal plates mounted in the case body, and a plurality of thin plate seal plates mounted in the case body mounted with the plurality of thin plate seal plates spaced apart from each other by a plurality of thin plate seals. The plate is formed by impregnating a felt-like material composed of a fiber body obtained by three-dimensionally combining a resin fiber and a rubber elastic body with a lubricating oil.
[Selection] Figure 1

Description

  The present invention relates to a lubrication seal that can be used without replenishing oil for a long period of time between a screw groove and a ball of a ball screw shaft, which is a screw rolling part, and between a screw groove and a ball of a ball nut, in a ball screw device Relates to the device.

Conventionally, various devices have been proposed for this type of sealing device (see, for example, Patent Documents 1 and 2).
Patent Document 1 is configured such that a lubricant-containing rubber or a synthetic resin ring is attached to the end of a ball nut with a pressing member, and a preload is applied in the circumferential direction of the synthetic resin ring at a protruding portion of the pressing member.

Patent Document 2 is attached to a sliding member such as a nut as in Patent Document 1, and as described in the specification of a member to which a lubricating oil is applied, felt made of wool mixed polyester, sintered resin, etc. It has the merit that it can absorb and retain a larger amount of lubricant.
Furthermore, a structure as described in Patent Document 3 is known as a sealing device. In such a sealing device, thin plate sealing plates having holes corresponding to the cross-sectional shape perpendicular to the axis of the thread groove of the ball screw shaft are overlapped in the circumferential direction and held on the frame-shaped ring to the end of the ball nut. It is attached and is effective as a sealing device.

Further, a sealing device that is used after being attached to both end faces of a standard ball screw nut is known (for example, see Patent Document 4).
Japanese Patent Laid-Open No. 10-2395 Japanese Patent No. 3288961 Japanese Utility Model Publication No. 5-43310 JP 2002-147561 A

However, Patent Document 1 intends to maintain a contact state for a long time by applying a pressing force to a ball that is a rolling element that always contacts a lubricant supply member. Therefore, there is a problem that the lubrication mechanism becomes complicated.
Further, in Patent Document 2, even when a large amount can be absorbed and retained, when oil is adhered to the rolling elements, that is, the balls, the oil is supplied to this member in order to always act. It is necessary to add a lubricating oil occlusion body (tank function). In addition, the contact portion with the ball of the member to which the lubricating oil that holds the oil is applied loses its elasticity and composition deformation occurs with time, so that the contact state with the rolling ball deteriorates and the lubricating action decreases. There is a risk of it. Also, since the normal felt material has a large gap, the absorbed oil is also likely to flow out. Therefore, as described in the specification, a device such as a flow control valve is required between the occlusion body and the application body. It becomes.

Furthermore, since a general sealing material is used in Patent Document 3, there is no function as a lubrication mechanism even if the sealing function is good, and the lubricating oil cannot be stably supplied for a long period of time.
Further, in Patent Document 4, since the built-in lubricant holding member is composed of a sintered resin member having a porous structure, the lubricating oil for holding oil is applied in the same manner as the other conventional devices described above. The contact portion of the member with the ball loses its elasticity every time and causes compositional deformation, so that the contact state with the rolling ball is deteriorated and the lubricating action may be reduced. Therefore, in Patent Document 4, in order to replenish the lubricant from the outside to the screw rolling part, the replenishing member is attached to the side part separately from the member that contacts the screw groove and applies the lubricant. It is what.

  The present invention has been made in order to solve such conventional problems, and its purpose is to eliminate the complexity of the lubrication mechanism and to absorb and retain a larger amount of lubricant. To provide a so-called externally-attached ball screw lubrication seal device that enables contact lubrication that can stably supply lubricant oil for a long period of time and that also has a sealing function and is later attached to a standard ball screw nut. It is in.

  The invention according to claim 1 has a substantially cylindrical case body having attachment portions to both ends of the screw nut, a hole corresponding to the cross-sectional shape perpendicular to the axis of the thread groove of the ball screw shaft, and the circumferential direction. A plurality of thin plate sealing plates that are mounted in a case body while being shifted and overlapped, and a plurality of thin plate sealing plates that are mounted in the case body that are mounted with a plurality of thin plate sealing plates, and a plastic wiper that is mounted across a space, A ball screw lubrication seal device, wherein a plurality of thin plate seal plates are formed by impregnating a felt-like material composed of a fiber body in which resin fibers and a rubber elastic body are three-dimensionally fused with a lubricating oil. .

The invention according to claim 2 is characterized in that a plurality of thin plate sealing plates are bonded to the inner peripheral surface of the case body with an outer peripheral surface obtained by shifting and overlapping in the circumferential direction with an adhesive. The ball screw lubricating seal device according to claim 1.
The invention according to claim 3 is characterized in that the lubricating oil is impregnated in each thin plate sealing plate after a plurality of thin plate sealing plates are shifted and overlapped in the circumferential direction and inserted and fixed in the case body. A lubrication seal device for a ball screw according to any one of claims 3 to 4.

According to the first aspect of the present invention, the elastic force of the rubber elastic body acts on the thread groove surface, whereby a long-term lubricating action can be achieved as compared with a normal felt material. In addition, it is possible to effectively perform the lubricating action without providing a mechanism for pressing from the outer peripheral side as in the conventional apparatus.
According to the invention of claim 2 and claim 3, since only the case body peripheral surface and the plurality of thin plate sealing plate outer peripheral surfaces are bonded and fixed, sufficient lubricating oil can be held on the thin plate sealing plate, and Since the inner peripheral side has a degree of freedom of movement, the sealing performance and the application of lubricating oil can be effectively performed by following the thread groove.

Furthermore, compared to ordinary felt material, it is made of a rubber elastic body, so the felt material is difficult to peel off, and dust entering from the outside can be captured in the oil retaining space of this thin seal plate, acting as a seal Can also serve.
Also, since the plastic wiper is located on the outermost side of the case body and the thin plate seal plate for lubrication is located with a space, dust from the outside can be removed with the plastic wiper. It can be pushed out and held there, or further captured by the lubricating thin plate sealing plate, to reliably prevent dust from entering the inside.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view of a ball screw lubricated seal device 1 according to an embodiment of the present invention incorporated in the end of a ball screw nut, and FIG. 2 shows the ball screw lubricated seal device 1 according to an embodiment of the present invention. FIG. 3 is a sectional view showing the relationship between the thin plate seal plates 7A, 7B, 7C and the ball screw rod 3 in the ball screw lubrication seal device 1 according to an embodiment of the present invention. .

  The ball screw lubrication seal device 1 according to the present embodiment has an attachment portion 9d to both ends of a screw nut 7 screwed into a spiral groove 5 of a ball screw shaft 3 via a rolling element (not shown) such as a steel ball. And a case body 9 having a substantially cylindrical shape and holes 11a, 11b, 11c corresponding to the cross-sectional shape perpendicular to the axis of the spiral groove 5 of the screw shaft 3, and being shifted in the circumferential direction to overlap with each other. Three thin plate seal plates 11A, 11B, and 11C mounted in 9a, and three thin plate seal plates 11A, 11B, and 11C in the case body 9 in which the three thin plate seal plates 11A, 11B, and 11C are mounted, Has a plastic wiper 13 mounted across a space 9e. Here, the outer peripheral surfaces of the three stacked thin seal plates 11A, 11B, and 11C and the inner peripheral surface of the case body 9 are fixed by an adhesive. The three thin seal plates 11A, 11B, and 11C are configured by impregnating a felt-like material including a fiber body obtained by three-dimensionally combining resin fibers and a rubber elastic body with a lubricating oil.

  The case body 9 is a substantially cylindrical case body having the same size as the outer shape of both ends of the screw nut 7, and a mounting portion 9 d that is screwed into a recess 11 a provided at both ends of the screw nut 7 at one end. A groove 9a for mounting the three thin seal plates 11A, 11B, and 11C, an annular projection 9c for forming the space 9e, and a groove 9b for mounting the plastic wiper 13 by screwing or bonding. And are provided.

  The three-dimensional sealing plate 11A, 11B, 11C, which comprises three-dimensional fusion of resin fibers and rubber elastic bodies, for example, has a rubber elastic body melted on the surface of thin polyester resin fibers. In this case, a large number of spaces are formed between the fibers. This space constitutes a lubricant supply means by impregnating a lubricant such as grease. In the resin fiber material, polyester is effective as the base resin, but is not limited to this.

Next, the operation of the thus configured ball screw lubrication seal device 1 according to this embodiment will be described.
First, as shown in FIGS. 1 and 2, the three thin plate seal plates 11A, 11B, and 11C impregnated with the lubricant are shifted in the circumferential direction and overlapped in the groove 9a of the case body 9, and the case body 9 After being adhesively fixed in the groove 9 a, the plastic wiper 13 is mounted in the groove 9 b outside the case body 9.

Next, the mounting portion 9 d of the case body 9 is screwed into the recesses 11 a provided at both ends of the screw nut 7.
Next, the ball screw shaft 3 is inserted into the hole 13a of the plastic wiper 13 and the holes 11a, 11b, 11c of the three thin seal plates 11A, 11B, 11C.
As a result, the holes 11a, 11b, and 11c of the three thin seal plates 11A, 11B, and 11C come into contact with the screw groove 5 of the ball screw shaft 3 as shown in FIG.

The holes 11a, 11b, and 11c of the three thin seal plates 11A, 11B, and 11C are pressed against the surface of the thread groove 5 of the ball screw shaft 3 by the elastic force of the rubber elastic body, and compared with a normal felt material. Long-term lubrication can be achieved.
At the same time, most of the dust from the outside is removed here by the plastic wiper 13 located outside the case body 9. And if a fine thing which could not be removed by the plastic wiper 13 enters the inside, it enters the space 9e and is left here. Further, the garbage to enter further is captured in the internal space between the fibers of the three thin seal plates 11A, 11B, and 11C and stays there. In this way, entry of dust from the outside can be surely prevented.

As described above, according to the ball screw lubrication seal device 1 according to the present embodiment, it is possible to effectively perform a lubrication operation without providing a mechanism for pressing from the outer peripheral side as in the conventional device. It became.
In the above embodiment, the case where three thin plate seal plates 11A, 11B, and 11C previously impregnated with lubricating oil have been described. However, the present invention is not limited to this, for example, after being inserted and fixed to the case body 9 The thin plate seal plates 11A, 11B, and 11C may be impregnated with lubricating oil.

Moreover, although the said embodiment demonstrated the case where three thin plate sealing plates 11A, 11B, and 11C were used, this invention is not restricted to this, The number of thin plate sealing plates is arbitrarily selected according to a use. Can do.
Furthermore, although the said embodiment demonstrated the case where the screw groove 5 of the ball screw shaft 3 was 1 item | strip | row, this invention is not restricted to this, The number of the thread grooves 5 is arbitrary.

  Furthermore, in the above embodiment, the case has been described in which the attachment portion 9d of the case body 9 is attached by being screwed into the concave portions 11a provided at both ends of the screw nut 7. However, the present invention is not limited to this, The mounting structure is optional.

It is sectional drawing of the lubricous seal apparatus 1 of the ball screw which concerns on one Embodiment of this invention incorporated in the nut edge part of the ball screw. 1 is a perspective view showing a ball screw lubricated seal device 1 according to an embodiment of the present invention in an exploded state. It is sectional drawing which shows the relationship between each thin-plate sealing plate 7A, 7B, 7C and the ball screw rod 3 in the lubrication seal apparatus 1 of the ball screw which concerns on one Embodiment of this invention.

Explanation of symbols

1 Ball Screw Lubricating Seal Device 3 Ball Screw Shaft 5 Screw Groove 7 Ball Nut End 9 Case Body 11A, 11B, 11C Thin Plate Seal Plate 11a, 11b, 11c Thin Plate Seal Plate 11A, 11B, 11C Hole 13 Plastic Wiper

Claims (3)

A substantially cylindrical case body having attachment portions to both ends of the screw nut;
A plurality of thin plate sealing plates that have holes corresponding to the cross-sectional shape perpendicular to the axis of the thread groove of the ball screw shaft, and are mounted in the case body while being shifted in the circumferential direction,
A plastic wiper that is mounted in a space separated from the plurality of thin plate sealing plates in the case body in which the plurality of thin sealing plates are mounted;
A ball screw lubrication seal device, wherein the plurality of thin plate seal plates are formed by impregnating a felt-like material composed of a fiber body obtained by three-dimensionally fusing resin fibers and a rubber elastic body with a lubricating oil.   2. The ball screw according to claim 1, wherein the plurality of thin plate seal plates have an outer peripheral surface that is shifted and overlapped in a circumferential direction fixed to an inner peripheral surface of the case body with an adhesive. Lubricating seal device.   4. The lubricating oil is impregnated in each of the thin plate sealing plates after the plurality of thin plate sealing plates are shifted and overlapped in the circumferential direction and inserted and fixed in the case body. The lubrication seal apparatus of the ball screw of any one of these.

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