JP2014051992A - Contact shoe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem of a conventional contact shoe that a seizure is likely to occur at sliding portions of a shoe, piston and swash plate at the time of energization of a swash plate type compressor and irregular wear of these sliding portions generates irregular sound and noise.SOLUTION: A contact shoe 5 comprises a spherical surface 5A sliding on a sliding surface 4a acting as hemispherical recess part of a piston 4, an end surface 5B sliding on a slant plate 3, and a columnar cylindrical part 5C formed between these spherical surface 5A and end surface 5B. The outer peripheral surface of the cylindrical part 5C is formed with many linear oil grooves 5F. Under a non-operated state of a swash plate type compressor 1, lubricant separated from refrigerant is held in each of the oil grooves 5F of the cylindrical part 5C of the shoe 5. When the swash plate type compressor 1 is energized, the lubricant within the oil grooves 5F is supplied to the spherical surface 5A and the end surface 5B acting as the sliding parts. With this arrangement, it becomes possible to provide the contact 5 shoe having a more superior lubricity than that of the prior art.

Description

  The present invention relates to a shoe, and more particularly to an improvement of a shoe used in a swash plate compressor.

Conventionally, a hemispherical shoe used for a swash plate compressor is known, and this hemispherical shoe has a spherical portion sliding with a hemispherical concave portion on the piston side, and an end surface portion sliding with the swash plate. (For example, Patent Literature 1 to Patent Literature 4).
In recent years, swash plate compressors for automobiles have been required to reduce costs and cope with new refrigerants, and in particular, swash plate compressors are required to have high efficiency.
Therefore, in Patent Documents 1 to 4, the following improvement proposals for shoes are presented. That is, in Patent Document 1, the surface roughness of the sliding portion and the non-sliding portion in the spherical surface portion of the hemispherical shoe is made different. In Patent Document 2, the spherical surface portion is a stepped tapered surface. It has been proposed to do. Further, in Patent Document 3, it has been proposed that the outer peripheral edge of the hemispherical shoe is largely removed over the entire circumferential direction to make it a cylindrical shape. Further, in Patent Document 4, the spherical surface of the hemispherical shoe is proposed. It has been proposed to form a helical oil groove in the part.

JP 2001-153039 A JP 09-280166 A JP-A-10-220347 Japanese Patent Laid-Open No. 11-050959

By the way, in the swash plate compressor, the lubricating oil is also circulated in the refrigerant circulating in the circulation circuit so that the lubricating oil is supplied to the sliding portion between the shoe, the piston and the swash plate. It has become. However, in recent years, there is a tendency to reduce the amount of lubricating oil sealed in the refrigerant circulation circuit, so that sliding portions between the shoe, the piston, and the swash plate are subjected to severe lubrication conditions.
In particular, when the swash plate compressor is started, there is no lubricating oil in the refrigerant in the circulation circuit, so even if the refrigerant is circulated in the circulation circuit, the sliding of the shoe, piston and swash plate Lubricating oil cannot be sufficiently supplied to the moving part via the refrigerant. For this reason, conventionally, when the swash plate compressor is started, the sliding portion between the shoe, the piston, and the swash plate is likely to be seized, and abnormal noise or noise is generated due to abnormal wear of the sliding portion. .

In view of the circumstances described above, the present invention provides a spherical portion that slides with the hemispherical concave portion of the first movable member, and a second portion.
In a shoe including an end surface portion that slides with a flat surface of a movable member, and a cylindrical portion formed between the spherical surface portion and the end surface portion,
The outer peripheral surface of the cylindrical portion is configured not to slide with either the hemispherical concave portion of the first movable member or the flat surface of the second movable member, and a groove and a groove are formed on the outer peripheral surface of the cylindrical portion. In other words, a recess is provided and lubricating oil is held in the groove and / or recess.

  According to the configuration described above, when used as a shoe for a swash plate compressor, the lubricating oil separated from the refrigerant is held in the oil groove or recess of the shoe when the swash plate compressor is not activated. become. Therefore, at the time of starting the swash plate compressor, even if the lubricant is not mixed in the refrigerant, the lubricant held in the oil groove or the recess is a sliding portion of the spherical surface or end surface of the shoe. Will be supplied. Therefore, it is possible to provide a shoe having good lubricity even when the swash plate compressor is started.

FIG. 1 is a sectional view showing a main part in a swash plate compressor according to an embodiment of the present invention. FIG. 2 is a front view of the shoe shown in FIG. 1. Sectional drawing along the axial direction of the location shown by the arrow III in FIG. The schematic diagram which shows the state of the lubricating oil trapped by the flow of the refrigerant | coolant with respect to the oil groove 5F shown in FIG. 3, and the oil groove 5F. The front view of the shoe which shows other examples of the present invention. The front view of the shoe which shows other examples of the present invention. The front view of the shoe which shows other examples of the present invention. The front view of the shoe which shows other examples of the present invention. The front view of the shoe which shows other examples of the present invention. Sectional drawing which shows the other Example regarding the oil groove in FIG. 2, FIG. The front view of the shoe which shows other examples of the present invention. The front view of the shoe which shows other examples of the present invention. The front view of the shoe which shows other examples of the present invention. The front view of the shoe which shows other examples of the present invention. The front view of the shoe which shows other examples of the present invention. The front view of the shoe which shows other examples of the present invention.

Hereinafter, the present invention will be described with reference to the illustrated embodiment. FIG. 1 shows the internal structure of a swash plate compressor 1. The swash plate compressor 1 has a rotating shaft 2 rotatably supported by a housing (not shown). And a swash plate 3 attached to the rotary shaft 2, a plurality of pistons 4 that move forward and backward in a cylinder bore (not shown) of the housing, and the swash plate 3 that are disposed so as to face the inside of each piston 4 and A plurality of shoes 5 are provided.
The swash plate 3 is fixed obliquely with respect to the rotating shaft 2 or can change the inclination angle of the swash plate 3, and is sandwiched by two shoes 5 for each piston 4. . The flat surface of the swash plate 3 that slides with the shoe 5 is coated with a required sprayed layer, a plating layer, a resin coating, or the like. The configuration of the swash plate 3 that can be used in the present invention is not limited to the above, and various conventionally known swash plates can be used.
The piston 4 has a sliding surface 4a formed of a hemispherical recess so as to face each other, and the shoe 5 swings and slides with respect to the sliding surface 4a while The rotation of the plate 3 is converted into the reciprocating movement of the piston 4.
Such a configuration of the swash plate compressor 1 is conventionally known, and further detailed description thereof is omitted.

As shown in FIG. 2, the shoe 5 of this embodiment includes a spherical surface portion 5 </ b> A that slides with the sliding surface 4 a of the piston 4, an end surface portion 5 </ b> B that slides with the flat surface of the swash plate 3, A cylindrical cylindrical portion 5C formed between the spherical surface portion 5A and the end surface portion 5B is provided. The shoe 5 of the present embodiment can be manufactured using a sintered material, a resin material, or the like in addition to an iron-based, copper-based, or aluminum-based material.
A relief portion 5D made of a flat surface that does not come into contact with the sliding surface 4a on the piston 4 side is formed at the top of the spherical surface portion 5A. Thus, the relief portion 5D is formed between the sliding surface 4a and the relief portion 5D. Lubricating oil flows into the space.
The end surface portion 5B is a sliding surface that slides on the swash plate 3, and its central portion has a medium-high shape that bulges to the swash plate 3 side by about several μm with respect to the outer peripheral portion. . Thus, the lubricating oil is easily drawn between the end surface portion 5B and the swash plate 3. A chamfered portion 5E is formed on the outer peripheral edge of the end surface portion 5B.

Next, the cylindrical part 5C of the shoe 5 has a cylindrical shape with the same outer diameter in the entire axial direction, and the axial dimension of the cylindrical part 5C is twice the axial length of the spherical part 5A. Is set to about. The outer peripheral surface of the cylindrical portion 5 </ b> C that is in a columnar shape does not slide with the swash plate 3 and the sliding surface 4 a of the piston 4. In this embodiment, a plurality of linear oil grooves 5 </ b> F are formed on the outer peripheral surface of the cylindrical portion 5.
The oil grooves 5F are inclined at 45 degrees with respect to the axis C of the shoe 5 and are formed on the outer peripheral surface of the cylindrical portion 5C at an equal pitch in the circumferential direction. One end of each oil groove 5F reaches the spherical surface portion 5A, and the other end of each oil groove 5F reaches the chamfered portion 5E, that is, the outer peripheral edge of the end surface portion 5B.
Moreover, as shown in FIG. 3, the cross-sectional shape of the oil groove 5F is a horizontally long rectangle having the same depth and a wide width with respect to the depth. The width of the oil groove 5F is preferably 0.01 to 2 mm, and the depth of the oil groove 5F is preferably 0.001 to 1 mm.
Thus, the shoe 5 of the present embodiment has a plurality of oil grooves 5F formed on the outer peripheral surface of the cylindrical portion 5C from the end surface portion 5B to the spherical portion 5A. In the present embodiment, the oil groove 5F is formed on the outer peripheral surface of the cylindrical portion 5C by knurling, turning, etching, or the like.

According to the shoe 5 of this embodiment, the lubricating oil retainability is improved as compared with the above-described conventional shoe, and the lubricity is improved.
This will be described in detail. As shown in FIG. 4, when the refrigerant containing lubricating oil flows in the axial direction in the vicinity of the outer peripheral surface of the cylindrical portion 5C, the lubricating oil contained in the refrigerant is The oil enters the 5C oil groove 5F, where it is easily captured and separated from the refrigerant.
Therefore, when the swash plate compressor 1 is not activated, that is, when the refrigerant in the circulation circuit is not circulated, the lubricating oil separated from the refrigerant is held in each oil groove 5F. . When the swash plate compressor 1 is started, no lubricating oil is mixed in the refrigerant. However, since the lubricating oil is previously held in each oil groove 5F of the shoe 5, the sliding of the shoe 5 is prevented. Accordingly, the lubricating oil is supplied from each oil groove 5F to the spherical surface portion 5A and the end surface portion 5B which are sliding portions. That is, when the swash plate compressor 1 is started, the lubricating oil held in the plurality of oil grooves 5F is supplied to the spherical surface portion 5A and the end surface portion 5B which are sliding portions, so that the shoe 5 with good lubricity is provided. be able to. In addition, the shoe 5 of the present embodiment is formed with the cylindrical portion 5C, and the shoe 5 itself is lighter than the conventional hemispherical shoe.
Therefore, by using the shoe 5 of this embodiment, it is possible to suppress the occurrence of seizure and abnormal noise in the sliding portion between the shoe 5 and the swash plate 3 and the sliding surface 4a, and high durability. It is possible to provide a highly efficient swash plate compressor 1.

  Next, FIGS. 5 to 9 show other embodiments to which the present invention is applied, in which the arrangement direction and shape of the oil groove 5F are changed. That is, the shoe 5 shown in FIG. 5 is formed by inclining the oil groove 5F by 45 degrees with respect to the axis C so that the oil groove 5F is inclined in the direction opposite to that of the first embodiment.

  Next, FIG. 6 shows V-shaped oil grooves 5F formed on the outer peripheral surface of the cylindrical portion 5C at an equal pitch in the circumferential direction. One end of each V-shaped oil groove 5F reaches the spherical surface portion 5A, and the other end of the oil groove 5F reaches the chamfered portion 5E (the outer peripheral edge of the end surface portion 5B).

  Next, FIG. 7 shows a case where linear oil grooves 5F parallel to the axial direction are formed at an equal pitch on the outer peripheral surface of the cylindrical portion 5C. One end of each oil groove 5F reaches the spherical portion 5A, and the other end reaches the chamfered portion 5E (the outer peripheral edge of the end surface portion 5B).

Next, FIG. 8 shows a spiral oil groove 5F formed on the outer peripheral surface of the cylindrical portion 5C. One end of the oil groove 5F reaches the spherical surface portion 5A, and the other end reaches the chamfered portion 5E (the outer peripheral edge of the end surface portion 5B).
5 to 8 described above is configured such that the spherical surface portion 5A, which is a sliding portion, and the end surface portion 5B communicate with each other via the oil groove 5F. That is, the lubricating oil held in the oil groove 5F is supplied to the spherical surface portion 5A and the end surface portion 5B as in the first embodiment shown in FIG. 2 when the shoe 5 moves.
In the shoe 5 of each embodiment shown in FIGS. 2 to 8, one end of the oil groove 5F reaches the spherical surface portion 5A and the other end of the oil groove 5F reaches the end surface portion 5B. The other end of the groove 5F may not reach the end surface portion 5B. That is, in this case, one end of the oil groove 5F reaches the spherical surface portion 5A.

Further, the shoe 5 of the embodiment shown in FIG. 9 is formed by forming annular oil grooves 5F in the direction orthogonal to the axis C at an equal pitch on the outer peripheral surface of the cylindrical portion 5C. In each embodiment shown in FIGS. 5 to 9, the cross-sectional shape of the oil groove 5F is the same rectangular cross-sectional shape as that of the first embodiment.
In each of the embodiments shown in FIGS. 5 to 9, the same operation and effect as the first embodiment of FIG. 2 can be obtained.

  In addition, you may change the cross-sectional shape and arrangement density of the oil groove 5F in each Example mentioned above as shown in FIG. That is, FIG. 10A shows a triangular cross section of the oil groove 5F, and FIG. 10B shows a circular cross section of the oil groove 5F. Further, FIGS. 10C to 10E show an embodiment in which adjacent oil grooves 5F are arranged as close as possible.

Next, FIGS. 11 to 12 show still other embodiments of the present invention. In these embodiments, a large number of recesses 5G are formed on the outer peripheral surface of the cylindrical portion 5C instead of the oil grooves 5F. It is a thing. That is, in FIG. 11, circular concave portions 5G having the same dimensions are formed in a staggered manner on the outer peripheral surface of the cylindrical portion 5C.
Moreover, in FIG. 12, the square recessed part 5G of the same dimension is formed in the outer peripheral surface of the cylindrical part 5C. Instead of the circular or square recess 5G, a large number of triangular or elliptical recesses may be formed on the outer peripheral surface of the cylindrical portion 5C.
Thus, even with the shoe 5 in which a large number of recesses 5G are formed on the outer peripheral surface of the cylindrical portion 5C, the same operations and effects as those of the first embodiment described above can be obtained.

Next, FIGS. 13 to 15 show other embodiments of the present invention, and these embodiments are obtained by changing the shape of the cylindrical portion 5C.
That is, in FIG. 13, the cylindrical portion 5C of the shoe 5 is formed in a tapered shape in which the spherical portion 5A side is gradually reduced in diameter compared to the end surface portion 5B side. A plurality of oil grooves 5F similar to those of the first embodiment of FIG. 2 are formed on the outer peripheral surface of the tapered cylindrical portion 5C.
Further, FIG. 14 shows that the cylindrical portion 5C of the shoe 5 is formed in a tapered shape in which the diameter of the end surface portion 5B is gradually reduced as compared with the spherical surface portion 5A, and the tapered cylindrical portion 5C is formed. A straight oil groove 5 </ b> F is formed on the outer peripheral surface.
Further, FIG. 15 shows a drum-shaped cylindrical portion 5C that bulges radially outward so that the central portion in the axial direction has the maximum outer diameter, and a plurality of linear oil grooves are formed on the outer peripheral surface thereof. 5F is formed.
Even with the shoe 5 of each embodiment shown in FIGS. 13 to 15, the same operation and effect as the first embodiment can be obtained. Also in the embodiments of FIGS. 13 to 15, a large number of recesses 5G shown in FIGS. 11 and 12 may be formed on the outer peripheral surface of the cylindrical portion 5C instead of the oil groove 5F.
In the shoe 5 of each embodiment shown in FIGS. 13 to 15, one end of the oil groove 5F reaches the spherical surface portion 5A and the other end of the oil groove 5F reaches the end surface portion 5B. The other end of the groove 5F may not reach the end surface portion 5B. That is, in this case, one end of the oil groove 5F reaches the spherical surface portion 5A.

FIG. 16 shows another embodiment of the present invention. In this embodiment, in the first embodiment shown in FIG. 2, a flange portion 5H is projected from the outer peripheral edge of the end surface portion 5B. On the premise of such a configuration, a linear oil groove 5F is formed on the outer peripheral surface of the cylindrical portion 5C of the shoe 5 in the same manner as in the first embodiment. Other configurations are the same as those of the first embodiment. Even with the shoe 5 shown in FIG. 16, the same actions and effects as those of the above embodiments can be obtained.
Also in the shoe 5 of the embodiment shown in FIGS. 2 to 9 and FIGS. 11 to 15, the flange portion 5 </ b> H may protrude from the outer peripheral edge of the end surface portion 5 </ b> B as in FIG. 16.

  Furthermore, instead of the linear oil groove 5F in each of the above-described embodiments, a lattice-like oil groove may be provided on the outer peripheral surface of the cylindrical portion 5C, and the oil groove 5F and the recess 5G may be provided as a cylinder. You may attach to the outer peripheral surface of 5 C of shape parts.

3. Swash plate (second movable member) 4. Piston (first movable member)
4a ··· Sliding surface 5 ··· Shoe 5A ··· Spherical surface portion 5B ··· End face portion 5C ··· Cylindrical portion 5F ··· Oil groove 5G ··· Recess portion

Claims (10)

A spherical portion that slides with the hemispherical concave portion of the first movable member, an end surface portion that slides with the flat surface of the second movable member, and a cylindrical portion formed between the spherical portion and the end surface portion. In the shoe
A shoe characterized in that grooves and / or recesses are provided on the outer peripheral surface of the cylindrical part, and lubricating oil is held in the grooves and / or recesses.   The shoe according to claim 1, wherein the cylindrical portion is formed in a columnar shape having the same outer diameter in the entire axial direction.   The shoe according to claim 1, wherein the cylindrical portion has a tapered shape in which the spherical portion side has a smaller diameter than the end surface portion side.   The shoe according to claim 1, wherein the cylindrical portion has a tapered shape in which the end surface portion side has a smaller diameter than the spherical surface portion side.   The shoe according to claim 1, wherein the cylindrical portion has a drum shape bulging radially outward so that a central portion in the axial direction has a maximum outer diameter.   The shoe according to any one of claims 2 to 5, wherein a flange portion extending radially outward is formed on an outer peripheral edge of the end surface portion.   The shoe according to any one of claims 1 to 6, wherein a plurality of the grooves are provided, and one end of each groove reaches the spherical portion.   A plurality of the grooves are provided. One end of each groove reaches the spherical surface portion, and the other end of each groove reaches the end surface portion. The spherical surface portion and the end surface portion communicate with each other through the plurality of grooves. The shoe according to any one of claims 1 to 5, wherein:   The shoe according to claim 7 or 8, wherein the grooves are linear, V-shaped, or lattice-shaped, and are provided at an equal pitch on the outer peripheral surface of the cylindrical portion.   The shoe according to any one of claims 1 to 6, wherein a plurality of the recesses are provided, and each recess is one of a circle, a square, a triangle, and an ellipse.

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