Spring cover

Abstract

To provide a spring cover capable of reducing time and labor of an operator by eliminating the need of work applying a lubricant, and continuously holding high lubricity.SOLUTION: A spring cover 100 protecting an outer periphery of an expansion / contraction member 10 provided in a gravity direction of a machine tool, is equipped with a spiral dustproof cover 110 that protects the expansion / contraction member 10 by expanding / contracting in a vertical direction along the gravity direction, an upper guide 120 disposed in an upper part in the gravity direction of the dustproof cover 110, an oil injection hole 132 formed on an outer surface 124a of the upper guide 120, and a discharge hole 134 that is formed on a ceiling surface of the upper guide 120, communicates with the oil injection hole 132, and discharges oil to an inner peripheral surface 110a of the dustproof cover 110 from the upper side in the gravity direction of the dustproof cover 110.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a spring cover that protects the outer periphery of an expandable member that extends in the direction of gravity of a machine tool. [Background technology]

[0002] Machine tools installed in factories and the like use expandable members such as ball screws, shafts, and cylinders. As a cover for covering and protecting these expandable parts, for example, Patent Document 1 discloses a spiral sliding body. The spiral sliding body of Patent Document 1 has the following structure: "After the surface of a strip-shaped elastic material is coated with a coating film having lubricity, elasticity, and physical strength such as polytetrafluoroethylene, the strip-shaped elastic material is wound spirally to form a spiral sliding body, and the upper and lower ends of each wound portion of the spiral sliding body are partially overlapped with each other, so that each wound portion is configured to be slidable and expandable." [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 6-071970 Summary of the Invention [Problem to be solved by the invention]

[0004] A cover (hereinafter referred to as a "spring cover") that encases and protects an expandable part expands and contracts while rotating, and its band-shaped portions (corresponding to the elastic bands in Patent Document 1) slide against each other in operation. Therefore, unless lubrication is ensured throughout the entire band-shaped portion, the cover is likely to be damaged during operation. Conventionally, lubrication has been ensured by periodically applying or spraying (hereinafter referred to as "application") lubricant to the band-shaped portion. However, Patent Document 1 discloses that forming a coating film on both sides of the elastic band reduces frictional resistance during expansion and contraction of each winding portion of the spiral sliding body, enabling smooth sliding of the winding portions without the need for lubricant application.

[0005] However, depending on conditions such as component costs and design dimensions, the spiral sliding body of Patent Document 1 may not be applicable. In such cases, it becomes necessary to manually apply lubricant to the band-shaped area, as in the conventional method. However, the work of applying lubricant is time-consuming, and the structure of the equipment makes it difficult to apply lubricant to the area that is on the back side as seen by the worker, which makes uneven lubrication more likely to occur. Furthermore, the lubricant is washed away in areas where machining coolant is sprayed, which tends to cause early damage.

[0006] In view of these problems, the present invention aims to provide a spring cover that reduces the worker's workload by eliminating the need to apply lubricating oil, and that can continuously maintain high lubricity. [Means for solving the problem]

[0007] In order to solve the above problems, a typical configuration of the spring cover of the present invention is a spring cover that protects the outer periphery of an expandable member arranged along the direction of gravity of a machine tool, and is characterized by comprising: a spiral-shaped dust cover that expands and contracts in the vertical direction along the direction of gravity to protect the expandable member; an upper guide that is arranged at the top of the dust cover in the direction of gravity; an oil injection hole formed on the outer surface of the upper guide; and a discharge hole formed on the ceiling surface of the upper guide that is connected to the oil injection hole and discharges oil from above the dust cover in the direction of gravity onto the inner surface of the dust cover.

[0008] Preferably, the upper guide has a groove formed therein that communicates with the oil injection hole and the discharge hole, and a plurality of discharge holes are arranged along the inside of the outer diameter of the dust cover. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a spring cover that eliminates the need for the worker to apply lubricating oil, thereby reducing the workload and enabling the spring cover to continuously maintain high lubricity. [Brief explanation of the drawings]

[0010] [Figure 1] 4A and 4B are diagrams illustrating a spring cover according to the present embodiment. [Figure 2] FIG. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] 10A and 10B are diagrams illustrating the position of a discharge hole in the mounting ring of the upper guide. DETAILED DESCRIPTION OF THE INVENTION

[0011] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Dimensions, materials, and other specific values ​​shown in the embodiments are merely examples for facilitating understanding of the invention and, unless otherwise specified, do not limit the present invention. In this specification and drawings, elements having substantially the same functions and configurations are designated by the same reference numerals to avoid redundant explanation, and elements not directly related to the present invention are not shown or described.

[0012] FIG. 1 is a diagram illustrating a spring cover 100 of this embodiment. The spring cover 100 shown in FIG. 1 is a member that protects the outer periphery of an expandable member 10 that is oriented along the direction of gravity (hereinafter referred to as "vertical") of a machine tool (not shown). FIG. 1 illustrates a ball screw as an example of the expandable member 10. The spring cover 100 includes a dust cover 110, an upper guide 120, and a lower guide 140. The dust cover 110 is a member made of a spirally wound metal band that expands and contracts in the vertical direction to protect the expandable member 10. The upper guide 120 and the lower guide 140 are disposed at the top and bottom of the dust cover 110, respectively.

[0013] 2 and 3 are diagrams illustrating the upper guide 120. FIGS. 2(a)-(c) are three-view diagrams of the upper guide 120, and FIG. 3 is an overall perspective view of the upper guide 120 including the AA cross section of FIG. 2(a). As shown in FIGS. 2 and 3, the upper guide 120 has an outer cylinder 122 and an attachment ring 124 disposed on the upper part of the outer cylinder 122. FIG. 4 is an overall perspective view of the lower guide 140. As shown in FIG. 4, the lower guide 140 has an inner cylinder 142 and a flange 144 disposed on the lower part of the inner cylinder 142.

[0014] 1, the dustproof cover 110 is wound so that its diameter decreases downward. The outer tube 122 of the upper guide 120 is disposed so as to cover the outside of the dustproof cover 110, and the inner tube 142 of the lower guide 140 is disposed so as to be inserted inside the dustproof cover 110. As a result, when the dustproof cover 110 is contracted, the dustproof cover 110 is housed between the outer tube 122 and the inner tube 142.

[0015] 2 and 3, bolt holes 126 are formed in the upper guide 120. The upper guide 120 is attached to the upper base 12 of the machine tool by inserting bolts (not shown) into these bolt holes 126. At this time, the dust cover 110 is stretched and tensioned between the upper base 12 and the lower base 14 of the machine tool (it acts as a tension spring), and the lower guide 140 is urged toward the lower base 14 of the machine tool.

[0016] In particular, in the present embodiment 100, as shown in FIGS. 1 to 3, an oil filling hole 132 and a discharge hole 134 are formed in the mounting ring 124 of the upper guide 120. The oil filling hole 132 is formed in the outer surface 124a of the mounting ring 124 of the upper guide 120 and is connected to the outside. The discharge hole 134 is formed in the ceiling surface of the upper guide 120, i.e., the lower surface 124b of the mounting ring 124, and is connected to the oil filling hole 132. With this configuration, when lubricating oil is injected into the oil filling hole 132 by the pump 20, the lubricating oil is discharged from the discharge hole 134 from above the dust cover 110 toward the inner circumferential surface 110a of the dust cover 110 (see FIG. 1).

[0017] Since the spring cover 100 is arranged along the vertically oriented expandable member 10, the lubricating oil discharged from the discharge hole 134 flows downward (in the direction of arrow B) along the inner circumferential surface 110a of the dust cover 110. Because the dust cover 110 is wound so that its diameter decreases downward, the upper edge of the wound spring band is on the inside. Therefore, when the lubricating oil flows down the inner circumferential surface 110a, it flows down along the spiral of the spring and is smoothly supplied to the gaps (sliding surfaces) between the spring bands. Therefore, with the spring cover 100 of this embodiment, the work of applying lubricating oil is unnecessary, reducing the labor of the worker. Furthermore, the lubricating oil is supplied to the sliding surface of the dust cover 110, thereby enabling high lubrication to be continuously maintained.

[0018] Furthermore, in the spring cover 100 of this embodiment, lubricating oil is supplied from the inner peripheral surface 110a of the dust cover 110, so the lubricating oil will not be washed away even if processing coolant is sprayed onto the dust cover 110. Therefore, lubrication can be reliably maintained, and the risk of damage caused by friction during operation can be significantly reduced.

[0019] In this embodiment, it is assumed that a manual pump is used as the pump 20, but this is not limiting and an automatic pump may also be used. The pump 20 may be directly connected to the oil filling hole 132, or may be configured to be connected to the oil filling hole 132 by a pipe (not shown) through which lubricating oil passes.

[0020] 1 to 3, in the spring cover 100 of this embodiment, an annular groove 136 (so-called oil reservoir) that communicates with the oil filling hole 132 and the discharge hole 134 is formed inside the mounting ring of the upper guide 120. A plurality of the discharge holes 134 (eight in this embodiment) are arranged along the inside of the outer diameter of the dust cover 110 (see FIG. 2(a)).

[0021] According to this configuration, the lubricating oil injected from the oil injection hole 132 reaches the discharge hole 134 via the groove 136. At this time, since a plurality of discharge holes 134 are arranged in the annular groove 136, the lubricating oil can be efficiently supplied to the entire circumferential direction of the dust cover 110. Therefore, it is possible to suppress the occurrence of uneven lubrication and enhance the above-mentioned effects.

[0022] While the present embodiment exemplifies a configuration in which eight discharge holes 134 are provided, this is not limiting and the number of discharge holes 134 may be changed as appropriate. Also, while Fig. 2(a) shows the eight discharge holes 134 arranged at equal intervals in the circumferential direction of the dustproof cover 110, this is not limiting either and the intervals between the plurality of discharge holes 134 may be set as desired. Regarding the shape of the groove 136, while the present embodiment exemplifies a circular ring shape, this is not limiting and the above-described effects can also be obtained with a different shape such as an arc shape.

[0023] 4, in the spring cover 100 of this embodiment, a discharge groove 146 is formed in the upper surface 144a of the flange 144 of the lower guide 140. This allows the lubricating oil that flows down the dust cover 110, from the lower end of the dust cover 110 to the inner tube 142 of the lower guide 140 and reaches the flange 144 to be discharged to the outside via the discharge groove 146 as shown in the direction of arrow C.

[0024] 5 is a diagram illustrating the position of the discharge hole 134 in the attachment ring 124 of the upper guide 120. The "position of the discharge hole 134," which is the distance from the center of the upper guide 120 to the center of the discharge hole 134, can be calculated using the following formula 1. R=Da-(φ / 2)+p …Equation 1 R: Position of the discharge hole 134 (distance from the center P of the upper guide 120 to the center of the discharge hole 134) D: outer diameter (radius) of the dust cover 110 a: Gap between the dust cover 110 and the outer cylinder 122 φ: diameter of discharge hole 134 p: Positive tolerance (e.g. +0~1)

[0025] Using the above formula 1, the position R of the discharge hole 134 can be set taking into consideration the outer diameter D of the dustproof cover 110, the gap a between the dustproof cover 110 and the outer cylinder 122, and the diameter φ of the discharge hole 134. Furthermore, since the positive tolerance p is also taken into consideration according to the above formula 1, the discharge hole 134 can be positioned closer to the dustproof cover 110 while reducing the effects of dimensional errors in the upper guide 120. Therefore, it becomes possible to more reliably supply lubricating oil to the inner circumferential surface 110a of the dustproof cover 110.

[0026] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to these examples. It is clear that those skilled in the art can conceive of various modifications and alterations within the scope of the claims, and it is understood that these modifications and alterations also fall within the technical scope of the present invention. [Industrial Applicability]

[0027] The present invention can be used for a spring cover that protects the outer periphery of an expandable member that extends in the direction of gravity of a machine tool. [Explanation of symbols]

[0028] 10...expandable member, 12...upper base, 14...lower base, 20...pump, 100...spring cover, 110...dustproof cover, 110a...inner surface, 120...upper guide, 122...outer cylinder, 124...mounting ring, 124a...outer surface, 124b...lower surface, 126...bolt hole, 132...oil injection hole, 134...discharge hole, 136...groove, 140...lower guide, 142...inner cylinder, 144...flange, 144a...upper surface, 146...discharge groove

Claims

1. A spring cover that protects the outer periphery of an expansion and contraction member that is provided along the gravity direction of a machine tool, a spiral dust cover that expands and contracts in the vertical direction along the gravity direction to protect the expandable member; an upper guide disposed at an upper portion of the dustproof cover in the direction of gravity; an oil injection hole formed on the outer surface of the upper guide; a discharge hole formed in a ceiling surface of the upper guide, the discharge hole communicating with the oil injection hole, and discharging oil from above the dustproof cover in the direction of gravity onto an inner circumferential surface of the dustproof cover; Equipped with The dustproof cover is wound so that its diameter becomes smaller downward.

2. a groove formed inside the upper guide and communicating with the oil injection hole and the discharge hole; 2. The spring cover according to claim 1, wherein a plurality of the discharge holes are arranged along the inside of the outer diameter of the dust cover.

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