Member for guiding oscillating or rotating mobile element

Abstract

To provide a member for guiding an element that moves while oscillating or rotating.SOLUTION: A member has a body (10) that is made of a hardened metal material, includes cavities (20) discontinuously distributed in a bore (12) for assembling a mobile element (2) and acting as grease reservoirs (30), and is provided with means (26) for supplying grease. In the bore (12), a bearing surface (14) is defined on the outside of the cavities (20) and the supply means (26), and a non-bearing surface (16) is defined at the cavities (20) and the supply means (26). The bore (12) includes at least one region (40), the cavity (20) has a depth (P20) between 2 and 5 mm, and the amount of grease (30) in the cavity (20) per bearing surface (14) is between 0.05 and 0.3 g / cm2.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a member for guiding a moving element that vibrates or rotates. The present invention also relates to a mechanical system comprising such a member and a method for manufacturing such a member.

[0002] The field of the present invention is that of guide members that guarantee a guiding function during vibration or rotation in continuous or reciprocating motion.

Background Art

[0003] Conventionally, such guide members are constituted by rings and are designed to be combined with the ability to articulate elements such as shafts or spindles.

[0004] In practice, such mechanical systems are subjected to high stresses such as high pressure, corrosion, wear, and shock during operation. To improve their service life, lubrication is provided between the ring and the shaft.

[0005] For example, as described in Patent Documents 1 and 2 in the name of the applicant of the present application, the ring can be provided with a mechanism that acts as a grease reservoir. When the mechanical system is in use, the grease gradually exits from the mechanism and lubricates the friction interface between the ring and the shaft. Therefore, this mechanism makes it optional to perform lubrication only during assembly or, otherwise, at very long lubrication time intervals.

[0006] Bronze, composite materials, and polymer rings have the advantage that they conform to the shape of the shaft when subjected to high loads and can thus reduce the normal pressure. The reduction in the PV value (pressure × velocity) thus leads to a reduction in wear. However, their low surface hardness results in low resistance to abrasive wear.

[0007] Therefore, with respect to rings that are subjected to high loads and high wear, it is customary to use steels with high mechanical properties (tensile yield strength Re > 800 MPa) and high hardness. These steels are heat-treated and have a bainite or martensite structure. However, due to their high mechanical properties, these rings cannot adapt to shaft deflection, resulting in very high local PV values and, consequently, wear and then seizure.

[0008] The applicant of the present application has extensive expertise in the field of guide members and is constantly trying to improve existing systems.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0010] The object of the present invention is to propose an improved guide member having excellent resistance to wear and seizure and a long service life.

Means for Solving the Problems

[0011] Therefore, the present invention relates to a member for guiding a moving element that vibrates or rotates, comprising a body made of a hardened metal material (a metal material subjected to a hardening treatment), the body being provided with a lumen for assembling the moving element, the lumen including cavities that are discontinuously distributed and can act as grease reservoirs, and optionally comprising grease supply means, wherein in the lumen, a bearing surface is defined outside the cavities and the supply means, and a non-bearing surface is defined for the cavities and the supply means. In the member, the lumen includes at least one region, the cavities have a depth between 2 and 5 mm, and the amount of grease in the cavities per bearing surface is between 0.05 and 0.3 g / cm 2 and is characterized in that it is between.

[0012] Accordingly, the present invention makes it possible to propose a guiding member that is resistant, efficient, and easy to install. This member is particularly well-suited for mechanical systems that operate under heavy loads and are exposed to impacts in wear environments, such as civil engineering, mining, agricultural, or industrial machines (e.g., in the steel sector) equipped with joints.

[0013] According to other advantageous characteristics of the present invention, individually or in combination, - The amount of grease per bearing surface is between 0.05 and 0.2 g / cm 2 and is between. - The depth of the cavities is between 3 and 5 mm, preferably equal to 4 mm. - The body has a radial thickness greater than 5 mm, preferably greater than 6 mm. - The metal material of the body has a yield strength Re between 200 and 600 MPa. - The metal material of the body is steel. - The grease supply means includes at least one through-hole between the outer surface and the lumen of the body. - The grease supply means includes at least one annular groove formed in the lumen. - The grease supply means includes at least one annular groove formed on the outer surface of the body. - The body, particularly when an annular groove is formed in the lumen, does not have a groove on its outer surface. - The grease preferably has a density (ISO2811) between 0.85 and 1.05 g / cm 3 , for example equal to 0.9 g / cm 3 .

[0014] As a non-limiting example, the grease may be selected from the reference examples "SNR Lub EP2", "BP energrease LS EP2" and "Tutela grease MRM2". - The inner cavity is preferably cylindrical. - The inner cavity is provided with a surface coating. - The surface coating is applied to the bearing surface and to the cavity after the formation of the cavity. - The surface coating is applied to the bearing surface before the cavity is formed. - The treatment or coating has physical properties different from those of the base metal material of the body. - The treatment or coating is multi-layer or single-layer. - The coating is made by physical vapor deposition (PVD). - The coating is made by chemical vapor deposition (CVD). - The coating is made by hot spray. - The coating is made by cold spray. - The coating is sprayed in powder form. - The coating is sprayed in the form of droplets. - The coating is made by high velocity oxy-fuel (HVOF). - The coating is made by laser cladding. - The coating is anti-seize. - The coating consists of an outer layer of DLC (diamond-like carbon) amorphous carbon, especially with a thickness between 1 and 5 μm, for example 3 μm. - The coating consists of an outer layer of a self-lubricating composite material, especially resin and / or woven or non-woven reinforced base, containing a filler such as PTFE, MoS2 or graphite. - The coating consists of a polymer varnish. - The treatment is nitriding. Preferably, the inner cavity has a bonding layer (white layer) having a thickness of especially between 5 and 50 μm, for example 20 μm. - The treatment is carburizing. Preferably, the carburizing is carried out with a thickness between 0.5 and 4 mm, for example 2 mm. - The treatment is solid immersion. - The treatment is induction immersion, preferably at high frequency. - The inner cavity has a surface layer treated to prevent seizure over a diffusion depth of 0.6 mm or less and having a hardness of 500 Hv1 or more over a depth between 5 and 50 μm. - The region extends 360 degrees around the longitudinal axis of the body over the entire inner cavity. - The region extends into the inner cavity over an angular sector of at least 120 degrees around the longitudinal axis of the body. - Two regions each extend into the inner cavity over an angular sector of at least 120 degrees around the longitudinal axis of the body. Preferably, the two regions are provided on both sides of the axis. - The region can have several different types of or only one type of cavity. - The cavity has a circular cross-section. - The cavity has a honeycomb cross-section. - Each cavity has a major axis or diameter between 2 and 15 mm, for example 6 mm. - The cavity has a surface density between 5 and 65%, defined as the ratio of the non-bearing surface to the bearing surface in the above-mentioned region containing the cavity. - The cavity does not open laterally on the side surface of the body.

[0015] The present invention also targets a mechanical system comprising a guiding member as described above and an element that vibrates or rotates and moves within this guiding member.

[0016] The present invention is a method for producing a member for guiding a moving element that vibrates or rotates, the method comprising the following successive steps, a) A step of manufacturing a body made of a metallic material, provided with an inner cavity for assembling a moving element, including cavities that are discontinuously distributed in the inner cavity and can act as grease reservoirs, and optionally provided with grease supply means, wherein in the inner cavity, a bearing surface is defined outside the cavities and the supply means, and a non-bearing surface is defined for the cavities and the supply means, the inner cavity includes at least one region, and the cavities have a depth between 2 and 5 mm. b) A step of performing a hardening treatment on at least the above-mentioned region in the inner cavity. c) A step of applying grease to at least the above-mentioned region in the inner cavity, wherein the amount of grease in the cavity per bearing surface is between 0.05 and 0.3 g / cm 2 in the above-mentioned region. The method is also targeted and characterized by including this step.

[0017] According to an embodiment of the above manufacturing method, in the step of applying grease to the inner cavity, the amount of grease in the cavity per bearing surface is between 0.05 and 0.2 g / cm 2 in the above-mentioned region.

[0018] The present invention will be better understood by reading the following description, which is given merely as a non-limiting example and made with reference to the accompanying drawings.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0020] FIGS. 1 to 3 illustrate a mechanical system according to the present invention, which includes a guide ring (1) according to the present invention and a main shaft (2) that vibrates or rotates and moves in the ring (1).

[0021] The ring (1) includes a tubular body (10) centered on the longitudinal axis (X10). The body (10) has an outer cylindrical surface (11) and an inner cylindrical surface that forms a lumen (12) for receiving the main shaft (2). The body (10) is made of a metal material that has undergone a hardening treatment, such as nitriding, carburizing, or dipping. Preferably, the body (10) is made of steel having a yield strength Re between 200 and 600 MPa.

[0022] The body (10) includes cavities (20) that are distributed in the lumen (12) and can act as grease reservoirs (30). The cavities (20) are discontinuously distributed in the lumen (12), that is, they do not communicate with each other. Preferably, the cavities (20) are regularly distributed in the lumen (12) around and / or along the axis (X10).

[0023] The cavities (20) can have any shape. For example, the cavities (20) can have a circular radial cross-section with a diameter (D20) and a rectangular axial cross-section with a depth (P20). In practice, the depth (P20) is measured at the bottom of the cavity (20) at the point farthest from the surface of the lumen (12).

[0024] The body (10) also comprises means (26) for supplying grease (30) to the inner cavity (12). For example, the supply means (26) includes an annular groove (27) formed on the outer surface (11), an annular groove (28) formed in the inner cavity (12), and at least one orifice (29) passing through the body (10) between the grooves (27, 28). The annular grooves (27, 28) are formed around the axis (X10). Preferably, the supply means (26) comprises several orifices (29) distributed around the axis (X10), with two, three, four or more orifices (29). The means (26), more particularly the groove (28), is not connected to the cavity (20).

[0025] Alternatively, it is also possible for the supply means (26) not to have an outer groove (27). In fact, tests have shown that the inner groove (28) is sufficient to ensure the supply of grease (30) to the inner cavity (12).

[0026] In the inner cavity (12), a bearing surface (14) is defined outside the cavity (20) and the supply means (26), and a non-bearing surface (16) is defined for the cavity (20) and the supply means (26).

[0027] According to the invention, the inner cavity (12) includes at least one region (40) with the following. - The depth (P20) of the cavity (20) between 2 and 5 mm, and - The ratio of the amount of grease (30) in the cavity (20) divided by the bearing surface (14) between 0.05 and 0.2 g / cm 2 .

[0028] The grease (30) contained in the supply means (26) is not taken into account in the calculation of the grease (30) / bearing surface (14) ratio. Tests conducted by the applicant have shown that, in the case of a link that operates by vibrating or rotating, the grease (30) contained in the inner groove (28) has no effect on the lubrication of the inner cavity (12) because this groove (28) is not connected to the cavity (20). Furthermore, this groove (28) contributes to increasing the contact pressure between the spindle (2) and the ring (1) by reducing the bearing surface (14). These tests were carried out under the following conditions. - Ring (1) with an inner diameter of 80 mm / outer diameter of 95 mm / length of 60 mm - Pressure = 50 MPa - PV: 0.21 MPa.m / s - Only initial lubrication. - Comparison between rings (1) with and without the inner lubrication groove (28).

[0029] The service life of the ring (1) without the inner lubrication groove (28) is twice as long as that of the ring (1) with the inner lubrication groove (28).

[0030] The results obtained are contrary to some prior art publications that claim that all the grease (30) contained in the ring (1), including the grease (30) contained in the outer and inner grooves (27, 28), is "effective".

[0031] Preferably, the depth (P20) of the cavity (20) in the region (40) is between 3 and 5 mm. More preferably, the depth (P20) is equal to 4 mm.

[0032] In the example of FIGS. 1 to 3, the region (40) extends over the entire inner cavity (12) and 360 degrees around the axis (X10) of the body (10). In other words, a cavity (20) with a depth (P20) between 2 and 5 mm is provided over the entire inner cavity (12).

[0033] Preferably, the inner cavity (12) has a surface layer (50) that is treated to prevent seizure over a diffusion depth (P50) of 0.6 mm or less and has a hardness of 500 Hv1 or more over a depth (P52) between 5 and 50 μm.

[0034] Two test runs were conducted by changing some parameters such as the dimensions of the ring (1), the dimensions of the cavity (20), and the material of the main shaft (2).

[0035] For the first test run, Table 1 presents the test conditions used for this run, while Table 2 and Table 3 present a different series of tests and the results obtained.

[0036] [Table 1]

[0037] [Table 2]

[0038] The results of the tests conducted with the large ring dimensions are given in Table 3 below.

[0039] [Table 3]

[0040] For the second test run, Table 4 presents the test conditions used for this run, while Table 5 presents a series of tests and the results obtained.

[0041] [Table 4]

[0042] [Table 5]

[0043] According to the results of the two test runs, the performance corresponding to the number of repetitions before seizure is 0.05 g / cm2 ~0.3 g / cm 2 Among them, and most specifically 0.05 g / cm 2 ~0.2 g / cm 2 It should be noted that it is maximum with respect to the amount of grease per bearing surface between them.

[0044] Other embodiments of the guide member (1) according to the present invention are illustrated in FIGS. 4 to 9. Some components of the member (1) correspond to those of the first embodiment described above, and for the purpose of simplification, have the same reference numerals.

[0045] FIG. 4 shows a guide member (1) that includes a cavity (20) but no grease supply means (26). In the inner cavity (12), a bearing surface (14) is defined outside the cavity (20), and a non-bearing surface (16) is defined in the cavity (20).

[0046] FIG. 5 shows a cavity (20) having a diameter (D20) smaller than the depth (P20).

[0047] FIG. 6 shows a cavity (20) having a diameter (D20) larger than the depth (P20).

[0048] FIG. 7 shows an inner cavity (12) including a region (42) that extends over an angular sector of 120 degrees around the longitudinal axis (X10). In the inner cavity (12), a cavity (20) having a depth (P20) between 2 and 5 mm is provided only in this region (42). Outside the region (42), the inner cavity (12) has no cavity that acts as a grease reservoir (30).

[0049] Figure 8 shows a lumen (12) including a region (42) extending over an angular sector of 180 degrees around the longitudinal axis (X10). In the lumen (12), a cavity (20) having a depth (P20) between 2 and 5 mm is provided only in this region (42). Outside the region (42), the lumen (12) is provided with a cavity (22) that acts as a grease reservoir and has a depth of less than 2 mm, for example 1 mm. These cavities (22) are not considered for the calculation of the grease (30) / bearing surface (14) ratio in the region (42).

[0050] Figure 9 shows a lumen (12) including two regions (44, 46) each extending over an angular sector of 120 degrees around the longitudinal axis (X10). The regions (44, 46) are provided facing each other on both sides of the axis (X10).

[0051] Moreover, the guide member (1) can have a shape different from that in FIGS. 1 to 9 without departing from the scope of the present invention defined in the claims. Furthermore, the technical characteristics of the various embodiments and modifications described above can be combined in whole or in part. Therefore, the guide member (1) can be applied with respect to cost, functionality, and performance.

Explanation of Reference Numerals

[0052] 1 Guide ring, guide member 2 Spindle 10 Tubular body 11 Outer cylindrical surface, outer surface 12 Lumen 14 Bearing surface 16 Non-bearing surface 20 Cavity 22 Cavity 26 Supply means 27 Annular groove, outer groove 28 Annular groove, inner groove, inner lubrication groove 29 Orifice 30 Grease reservoir, grease 40, 42, 44, 46 Regions 50 Surface layer D20 Diameter P20 Depth P50 Diffusion Depth P52 Depth X10 Longitudinal Axis

Claims

1. A guide member (1) for an element (2) that moves by vibrating or rotating, comprising a body (10) made of a hardened metal material, the body (10) being provided with a lumen (12) for assembling the moving element (2), the lumen (12) including cavities (20) that are discontinuously distributed and can act as grease reservoirs (30), and means (26) for supplying optional grease (30), a bearing surface (14) being defined in the lumen (12) outside the cavities (20) and the supply means (26), and a non-bearing surface (16) being defined for the cavities (20) and the supply means (26), in the guide member (1), the lumen (12) including at least one region (40; 42; 44, 46), the cavities (20) having a depth (P20) between 2 and 5 mm, and the amount of grease (30) in the cavities (20) per bearing surface (14) being between 0.05 and 0.3 g / cm ２ The guide member (1) is characterized in that it is between.

2. The amount of grease (30) in the cavity (20) per bearing surface (14) is between 0.05 and 0.2 g / cm ２ The guide member (1) according to claim 1, characterized in that it is between.

3. The guide member (1) according to claim 1 or 2, characterized in that the depth (P20) of the cavity (20) in the region (40) is between 3 and 5 mm, preferably equal to 4 mm.

4. The guide member (1) according to any one of claims 1 to 3, characterized in that the inner cavity (12) is provided with a surface coating.

5. The inner cavity (12) is a surface layer (50) treated to prevent seizure over a diffusion depth (P50) of 0.6 mm or less, and has a surface layer (50) having a hardness of 500 Hv1 or more over a depth (P52) between 5 and 50 μm. The guide member (1) according to any one of claims 1 to 4, characterized in that it has.

6. The guide member (1) according to any one of claims 1 to 5, characterized in that the metal material of the main body (10) has a yield strength Re between 200 and 600 MPa.

7. The guide member (1) according to any one of claims 1 to 6, characterized in that the region (40) extends 360 degrees around the longitudinal axis (X10) of the main body (10) over the entire inner cavity (12).

8. The guide member (1) according to any one of claims 1 to 6, characterized in that the region (42) extends into the inner cavity (12) over an angular sector of at least 120 degrees around the longitudinal axis (X10) of the main body (10).

9. The guide member (1) according to any one of claims 1 to 6, characterized in that two regions (44, 46) each extend into the inner cavity (12) over an angular sector of at least 120 degrees around the longitudinal axis (X10) of the main body (10).

10. A mechanical system comprising the guide member (1) according to any one of claims 1 to 9 and an element (2) that vibrates or rotates and moves within the inner cavity (12) of the guide member (1).

11. A method for manufacturing a guide member (1) for an element (2) that moves by vibrating or rotating, the manufacturing method comprising the following successive steps, namely a) A main body (10) made of a metal material, provided with an inner cavity (12) for assembling the moving element (2), including cavities (20) that are discontinuously distributed in the inner cavity (12) and can act as grease reservoirs (30), and optionally means (26) for supplying grease (30). A step of manufacturing a main body (10) having In the inner cavity (12), a bearing surface (14) is defined outside the cavity (20) and the supply means (26), and a non-bearing surface (16) is defined in the cavity (20) and the supply means (26). a step in which the inner cavity (12) includes at least one region (40; 42; 44, 46), and the cavity (20) has a depth (P20) between 2 and 5 mm. b) a step of performing a hardening treatment on the inner cavity (12), at least on the region (40; 42; 44, 46). c) applying grease (30) at least to the region (40; 42; 44, 46) within the inner cavity (12), the amount of grease (30) within the cavity (20) per bearing surface (14) being between 0.05 and 0.3 g / cm ２ between, the step and, A manufacturing method, characterized by comprising the above steps.

12. In the step of applying grease (30) into the inner cavity (12), the amount of the grease (30) in the cavity (20) per bearing surface (14) is between 0.05 and 0.2 g / cm ２ The manufacturing method according to claim 11, characterized in that it is between.

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