JP4515750B2 - Ball screw lubrication seal device - Google Patents

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 portion, and between a screw groove and a ball of a ball nut, particularly 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.
Japanese Patent Laid-Open No. 10-2395 Japanese Patent No. 3288961 Japanese Utility Model Publication No. 5-43310

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.
The present invention has been made 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. It is an object of the present invention to provide a 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.

The invention according to claim 1 is a frame shape having a U-shaped cross-sectional shape in which a plurality of thin seal plates having holes corresponding to the cross-sectional shape perpendicular to the axis of the thread groove of the ball screw shaft are shifted in the circumferential direction. A lubricating seal device for a ball screw that is held on a ring and attached to the end of a ball nut, wherein the plurality of thin plate sealing plates are integrated by melting a rubber elastic body on the surface of a thin polyester resin fiber, A plurality of spaces formed between the resin fibers are impregnated with a lubricant to constitute a lubricant supply means, and the thin plate sealing plates are shifted in the circumferential direction and overlapped to form the frame ring. only inserting outer peripheral surface within, to have a freedom of movement to the inner peripheral surface side by sticking with an adhesive to the inner circumferential surface of said frame forms a ring, with respect to each of the thin seal plate the screw groove Follow to a lubricating sealing apparatus of the ball screw, characterized by comprising configured to perform the application of the lubricant as well as sealing the screw groove.

According to a second aspect of the present invention, in the lubricating oil, the plurality of thin plate sealing plates are shifted in the circumferential direction and overlapped and inserted into the frame-shaped ring, and only the outer peripheral surface is inserted into the inner periphery of the frame-shaped ring. 2. The ball screw lubricating seal device according to claim 1, wherein the thin plate seal plate is impregnated after being fixed to the surface by an adhesive .

According to the present invention, since the elastic force of the rubber elastic body acts on the thread groove surface, 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.
In addition, since only the inner peripheral surface of the frame-shaped ring and the outer peripheral surfaces of the plurality of thin plate sealing plates are bonded and fixed, sufficient lubricating oil can be held on the thin plate sealing plate, and the inner peripheral side has freedom of movement. Therefore, by following the screw groove, sealing performance and lubricating oil can be effectively applied.

  Furthermore, compared to ordinary felt material, it is made of rubber elastic body, so the felt material is hard to peel off, and dust entering from the outside can be captured in the oil holding space of this thin seal plate, acting as a seal Can also serve.

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 lubricating seal device 1 according to an embodiment of the present invention incorporated in the nut end of the ball screw, and FIG. 2 is a ball screw lubricated seal device 1 according to an embodiment of the present invention. FIG. 3 is a cross-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. is there.

  The ball screw lubrication seal device 1 according to the present embodiment includes three thin plate seal plates 7A, 7B, and 7C having holes 7a, 7b, and 7c corresponding to the cross-sectional shape perpendicular to the axis of the thread groove 5 of the ball screw shaft 3. It is configured by being shifted in the circumferential direction and superposed and bonded and held in the frame-shaped ring 9 and then attached to the attachment hole 13 of the ball nut end 11. Here, the outer peripheral surfaces of the three laminated thin seal plates 7A, 7B, and 7C and the inner peripheral surface of the frame-shaped ring 9 are fixed by an adhesive. The three thin seal plates 7A, 7B, and 7C 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 fiber body formed by three-dimensionally merging resin fibers and rubber elastic bodies, which constitute the three thin seal plates 7A, 7B, and 7C, for example, melts rubber elastic bodies 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 seal lubrication seal device 1 according to this embodiment will be described.
As shown in FIG. 2, the three thin plate seal plates 7A, 7B, and 7C impregnated with the lubricant are shifted in the circumferential direction and overlapped in the frame-shaped ring 9, and bonded and fixed in the frame-shaped ring 9, While inserting the ball screw shaft 3 into the holes 7a, 7b, 7c of the three thin seal plates 7A, 7B, 7C and the hole 9a of the frame-shaped ring 9, the frame-shaped ring is inserted into the mounting hole 13 of the ball nut end portion 11. Wear 9

Thereby, the holes 7a, 7b, and 7c of the three thin seal plates 7A, 7B, and 7C come into contact with the screw groove 5 of the ball screw shaft 3 as shown in FIG.
The holes 7a, 7b, and 7c of the three thin seal plates 7A, 7B, and 7C 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.

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.
Moreover, since the holes 7a, 7b, and 7c of the three thin seal plates 7A, 7B, and 7C are in contact with the screw grooves 5 of the ball screw shaft 3, as shown in FIG. Capturing in a large number of oil retaining spaces of the three thin seal plates 7A, 7B, 7C can prevent entry into the interior.

In the above embodiment, the case where the frame-shaped ring 9 is attached to the ball nut end portion 11 is described as being inserted and fixed in the attachment hole 13 of the ball nut end portion 11, but the present invention is limited to this. is not.
In the above embodiment, the case where the three thin seal plates 7A, 7B, 7C previously impregnated with the lubricating oil is used has been described. However, the present invention is not limited to this, and is inserted and fixed to the frame ring 9, for example. Later, the thin seal plates 7A, 7B, and 7C may be impregnated with lubricating oil.

Furthermore, in the above-described embodiment, the case where three thin plate seal plates 7A, 7B, and 7C are used has been described. However, the present invention is not limited to this, and the number of thin plate seal plates may be arbitrarily selected according to the application. Can do.
Furthermore, in the above embodiment, the case where the number of the thread grooves 5 of the ball screw shaft 3 is one has been described. However, the present invention is not limited to this, and the number of the thread grooves 5 is arbitrary.

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 Grooves 7A, 7B, 7C Thin Plate Seal Plates 7a, 7b, 7c Holes in Thin Plate Seal Plates 7A, 7B, 7C 9 Frame Ring 11 Ball Nut End 13 Mounting Hole

Claims (2)

A plurality of thin seal plates having holes corresponding to the cross-sectional shape perpendicular to the axis of the thread groove of the ball screw shaft are shifted in the circumferential direction and overlapped to be held in a frame-shaped ring having a U-shaped cross section, and at the end of the ball nut A ball screw lubrication seal device attached to a part,
The plurality of thin plate seal plates are made by integrating a rubber elastic body on the surface of a thin polyester resin fiber and integrating the lubricant into a large number of spaces formed between the resin fibers. It constitutes a supply means, and the respective thin plate sealing plates are shifted in the circumferential direction and overlapped and inserted into the frame-shaped ring, and only the outer peripheral surface is fixed to the inner peripheral surface of the frame-shaped ring with an adhesive. Thus, the inner peripheral surface side is provided with a degree of freedom of movement, and each thin plate sealing plate follows the screw groove to seal the screw groove and to apply the lubricating oil. A lubrication seal device for a ball screw. The lubricating oil is inserted in the frame-shaped ring by laminating and laminating the thin seal plates in the circumferential direction, and only the outer peripheral surface is fixed to the inner peripheral surface of the frame-shaped ring by an adhesive . 2. The ball screw lubricating seal device according to claim 1, wherein each of the thin plate seal plates is impregnated.

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