JPH01285678A - Cylindrical type piston compressor - Google Patents

Abstract

PURPOSE: To avoid actuation failure of a piston and a compressor caused by spill of oil by forming recesses for collecting oil flowing in a guide portion of the piston in a portion along a longitudinal direction of the piston opposite to a leakage exhaust chamber of a cylinder. CONSTITUTION: A crankshaft 2 supported in a crankcase 1 is connected to a piston 6 contained in a cylinder 7 via a rod 4. The piston 6 is provided with a guide portion 6a and a work portion 6b. An oil wiper device 20 is disposed in the guide potion 6a, and a leakage exhaust chamber 21 is formed in the work portion 6b. In this compressor, a suitable number of recesses 25 are formed in a portion A along a longitudinal direction of a piston 6 opposite to the leakage exhaust chamber 21. Then, the oil traveling along the surface of the guide portion 6a is collected by each recess 25, and the collected oil is conveyed to the leakage exhaust chamber 21 or the like.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention comprises at least one piston that is moved in a cylinder via a crankshaft and an articulating rod, the piston comprising: A guide part facing the crankcase and guided in the cylinder part attached to Il, reduced in diameter from this, is configured as a dry working gas sealing part, in particular a labyrinth piston, and defines a compression chamber in the cylinder. an oil wiper arrangement is provided in the movement area of the guide part, and a leakage drainage chamber is provided outside the slow movement area of the work part in the cylinder, which is connected to the low pressure chamber. The present invention relates to a cylindrical piston compressor configured to discharge gas leaking from a compression chamber and oil leaking from a crankcase.

[Prior Art 1] In the above type of cylindrical piston compressor known from Japanese Patent Application No. 61-257114 (P5994), 1ilPK! flows along the cylinder wall and enters the leakage discharge chamber. Since gas and leakage oil are reliably separated, the known cylindrical piston compressor is suitable for oil-free compression of gas. ,
However, in the known configuration, especially if the operation is carried out over a long period of time, leakage oil can pass through the connection between the guide part and the working part of the piston to the part of the cylinder surface that cooperates with this dry-acting working part. It may flow. This prevents lubricating oil from flowing into the compression chamber, which is inconvenient in order to allow the compressor to operate without any hindrance.

[Problem to be Solved by the Invention J] It is an object of the present invention to provide an improvement in this respect, which ensures that oil particles adhering to the guiding part are retained and separated from the cylinder surface part associated with the working part. Another object of the present invention is to provide a further developed cylindrical piston compressor.

[Means for solving the problem J] To this end, according to the invention, at least one part in the form of an annular groove is provided along the length of the piston, which enters the region of the leakage discharge chamber at the top dead center position d of the piston. Another recess is provided, which is adapted to collect the oil film running along the surface of the guide part and to direct this collected oil to the leakage drain chamber and/or to the lubricating cylinder part.

[Operation 1] As a result of the provision of the annular groove-shaped recess as described above according to the present invention, the oil particles adhering to the guide part can be moved through the movement area of the piston part 11 until they become separable oil droplets. held outside. Due to the maximum deceleration or acceleration of the piston that occurs during each reversal of the piston, these oil droplets are transferred to the leakage discharge chamber at the top dead center position of the piston, and to the 11 of the cylinder corresponding to the guide part of the piston at the bottom dead center position of the piston. It is thrown onto the surface where it is exposed.

Those improvements of the invention are set out in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS Other features and details of the invention will become apparent from the following description of embodiments of the invention, which are illustrated in the accompanying drawings.

The cylindrical piston compressor shown in FIG. 1 includes a crankshaft 2 mounted in a crankcase 1, and one mW of a connecting rod 4 is pivotally mounted on a crankshaft 3 of the crankshaft 2. The other end of the connecting rod is pivotally connected to a piston 6 by a piston pin 5. The piston is guided in a sealed manner in the cylinder 7. The cylinder is coupled to the crankcase 1 with its longitudinal axis horizontal. The illustrated cylinder 7 is 11
However, it is also possible to provide equivalent 21 cylinders, for example in positions opposite each other, or even more cylinders, for example 3 or 4 cylinders radially. In this case, each cylinder is provided with a piston and a connecting rod, which are driven by a common crankshaft.

The cylinder 7 is open towards the crankcase 1, but the cylinder end opposite the crankcase is bounded by the Ial wall 8 of the cylinder head 10. The cylinder head includes a suction chamber 11 and a discharge chamber 12. Suction chamber 11
is coupled to a compressed gas suction line (not shown) by an inlet 13, and the discharge chamber 12 is coupled to a compressed gas discharge line (not shown) by a discharge port 14. The piston 6 has a guide portion 6a facing the crankcase 1 and a work portion 6b facing the cylinder head 10.
and has. This working part is connected to the guide part by a reduced diameter Chinese piston part 6c. The working part 6b together with the end 98 defines the compression chamber 15. The compression chamber 15 is connected to the suction chamber 11 by a suction valve 17 provided in the end wall 8 and to the discharge chamber 12 by a discharge valve 18 .

The piston 6 is moved between a "top" dead center position shown by a solid line in FIG. 1 and a "bottom" dead center position 6' shown by an imaginary line (dashed line) by the crankshaft 2 driven in the direction of an arrow 16. It is driven back and forth between the In this reciprocating movement, the guide portion 6a
is guided in the corresponding cylinder part 7a and is lubricated by oil supplied and distributed from the crankcase 1. The guide part 6a is provided with a wiper ring 20, by means of which most of the supplied oil is returned to the crankcase 1. The oil collected in the wiper ring 20 is
It can be made to flow into the inside of the guide part 6a through a through hole (not shown) provided in the guide part 6a. The working part 6b is constructed as a dry working sealing part, which has a labyrinth sealing groove on its outer circumferential surface and forms a contactless seal with the cylinder part 7b surrounding the labyrinth.

The cylinder chamber is expanded into a ring shape between the cylinder parts 7a and 7b! jl leakage discharge chamber 21 is installed. This discharge chamber 21 has a lower pressure than the discharge chamber by a discharge duct 22. It is combined with (indication f). Exhaust duct 2
For example, a discharge line (not shown) can be connected to 2 to discharge gas leaking from the compression chamber 15 through the labyrinth seal and oil leaking without being retained by the wiper ring 20. Also, wiper ring 2
In order to eliminate the pressure gradient with both sides open at 0, the leakage discharge chamber 21 and the crankcase 1 may be connected by a pressure equalization line 24 connected to a duct 23 provided in the cylinder 7. Thereby, wear of the guide portion 6a and cylinder portion 7a during high-speed operation of the piston can be kept low.

At least two pieces (see FIG. (3) annular groove-shaped recesses 25, 25
a, 25b are provided. The recessed portion 25a is closer to the work portion 6b.

25b are the recesses 25 adjacent to each other on the side of the guide portion 6a.
, 2δa. The recesses 25.25a, 25b have rib-like protrusions 26, 2 on their respective sides that protrude from the adjacent piston portion 6c.
8a and 26b. The protrusions have sharp edges 27 extending around their entire periphery.

As is particularly clear in FIG. 1a, the recesses 25, 25a, 2
5b each have two substantially parallel sides 29 and 30. Recesses 25, 25a.

25b also includes an insert 28 for temporarily storing oil particles.
can be provided. These inserts have been omitted in FIG. 1 to avoid complicating the drawing. The inserts 28 are each suitable for collecting oil particles and allowing them to coalesce into separable oil droplets, and at the same time to collect oil from above or from the side by gravity, one part thick. 25. Made of a material sufficiently permeable to flow down into 25.25a, 25b, for example steel wool. The protrusions 1!1ls26.28a, 26b cause the l!ls26.28a, 26b to l! !
I! 25. 25a, 25b may be formed of thin 9-thick flexible strip-like wall sections that can be elastically deformed to narrow or widen.

The recesses 25.25a, 25b prevent the part 7b of the cylinder associated with the working part 6b from being damaged by oil adhering to the guiding part 6a. This is because the oil film that has been transmitted along the surface of the guide inner portion 6a enters the recess 25 at least in the final phase of the compression stroke of the piston 6 moving from left to right in FIG. The oil is retained until a separable oil drop is formed and is ejected from the recess 25 into the leakage discharge chamber 21 when a reversal movement of the piston takes place at the top dead center position of the piston 6 shown in FIG. is,
Also, depending on the case, the cylinder part 7 that falls to the bottom dead center position 7
This is because it is returned to the lubricated surface of a. The discharge of the oil at the top dead center position of the piston 6 is facilitated by the edge of the protrusion 26 adjacent to the compression stroke side of the recess 25. Similarly, from the recess 25 to the recess 25a, and depending on the case, the recess 1! The oil film P that has moved from $25a to the recess 25b (and other recesses if it can be installed) is also transferred to the recess 2.
5a, 25b, formed into oil droplets and ejected into the leakage discharge chamber 21 and the cylinder part 7a. This reliably prevents oil particles from being sent to the cylinder portion 7b.

Flexible protrusion 26.2 formed by a strip-like wall section
In the structure provided with 6a and 28b, a type of pumping action is obtained by elastic deformation of these wall portions due to the reciprocating movement of the piston 6, particularly the acceleration and deceleration in the region of the piston's double dead center positions.

This pumping action facilitates the collection of oil particles and the separation of the oil droplets formed thereby. In the illustrated embodiment, the depths of the recesses 25, 25a, 25b increase successively towards the working portion 6b, and the height of the flexible wall portions defining these recesses correspondingly increases. Become.

Thus the protrusion 1 is closer to the working part 6b! ! 26a
, 26bLL protrusion 1$26 closer to guide portion 6a
, 268. A stronger pumping action is therefore created in the deeper recesses 25a, 25b than in the shallower recesses 25, 25a.

A flexible protrusion 26.2 at the top dead center position of the piston 6
6a and 26b are recessed portions 25 and 25a.

25b to expand their volume, thus retaining oil within their recesses. On the other hand, at the bottom dead center position 4 of the piston 6, the protrusions 26, 26a, 26b are connected to the recesses 25, 25a.
, 25b to reduce their volume, thus forcing oil out of their recesses.

This results in the working part 6b being operated dry, i.e. most of the collected oil is dumped in the area of the lubricated part 7a of the cylinder, and a smaller amount of oil has to be kept dry. The leakage discharge chamber 21 adjacent to the cylinder portion 7b
The excellent effect of projecting it inward can be obtained.

FIG. 2 shows a configuration in which the part A of the piston 6 entering the area of the leakage discharge chamber 21 is provided with 11I recesses 25, and in this single recess a steel wool is provided as an insert for collecting oil particles. We show that this is also possible. The projection 8Is26 which defines the recess 25 in this figure is formed by a rigid wall section, so that said pumping action does not occur.

In FIG. 3, the sides 29.3 of the recesses 25, 25a, 25b are shown.
0 is inclined by an acute angle α with respect to the longitudinal axis of the piston 6, and the apex S of this angle is oriented toward the working portion 6b. During this deceleration when approaching, the oil film adhering to the guide portion 6a is introduced into the recess 25, and the oil particles not thrown out by the protrusion 26.26a are introduced into the recesses 25a, 25b. becomes easier to perform. Therefore, at the top dead center position of the piston 6, most of the collected oil is retained in the said inclined four parts 25, 25a, 25b, and at the bottom dead center position W16' of the piston 6, from these recesses the cylinder part 7a is removed. Easily thrown in the direction. In this structure also the protrusion 28.28a.

26b may be formed by either a rigid or flexible wall section; in FIG. 3 the angle (α) is 60°;
Other angles of 90° or smaller are also possible, and the minimum limit for that angle (α) will essentially be a matter of practical design.

In FIG. 4, the recesses 25.25a, 25b are disk-shaped loose rings which are spaced apart and fixed on the part 6c of the piston 6 by the spacer rings 32, 32a, 32b and the retaining ring 33! ! 31. In this construction, the working part 6b is connected to the piston part 6c by a screw 34. Also, as shown in Figure 4,
Instead of a labyrinth groove, the working part 6b carries a sealing ring 36 of a self-lubricating material suitable for dry operation, for example Teflon or graphite, by means of which the working part 6b is sealed in the cylinder part 7b. You will be guided by the condition. ring! ! Element 31 may be made of rigid or thin flexible sheet metal or plastic parts allowing said selective separation to take place. Spacer ring 32
, 32a.

By appropriately selecting the outer diameter and thickness of 32b, the recess 25.25 can be formed without requiring expensive processing on the piston 6.
a, 25 bt - the optimum size, and the size and number can be changed if necessary.

In the embodiment shown in FIG. 5, the oil wiper ring 20 associated with the guide part 6a is fixed in a carrier ring 37 which fits in an annular groove 38 provided in the part 7a of the cylinder 7. In the embodiment shown in FIG. The cylinder is divided by the number of annular m38. The ring P38 is connected to a discharge duct 22 connected to the leakage discharge chamber 21. The carrier ring 37 is connected to the through hole 4
0, whereby leaked oil and gas are discharged to the exhaust duct 22. In this embodiment, the working part 6b has a larger diameter than the guiding part 6a, and the guiding part is connected by a conical shoulder 44 to the piston part 6c.

Recesses 25.25a, 25b provided in this structure
is defined by the skin 81144 and the ring element 41 in the form of a conical shell.

These ring elements 41 are fixed at a distance from each other on the piston part 6c by spacer rings 42.42a, 42b in the form of conical shells and by a retaining ring 43. Side surfaces 29.30 of the recesses 25.25a, 25b, which are inclined with respect to the longitudinal axis (,) of the piston 6, are formed on the shoulder 44 and on the ring base 41.
1 is shown in FIG.

Ring element 41 is also made of rigid or flexible sheet metal or plastic parts. Subena ring 42, 42
By making a and 42b appropriately thin,
By making the distance between the sides 29 and 30 of the recesses 26, 25a and 25b small, for example one layer or less, a capillary action can be created between the sides 29 and 30.

Such capillary action facilitates the introduction of oil particles adhering to the guide portion 6a into the recesses 25.25a, 25b until oil droplets are formed and ejected from the recesses 25.25a, 25b. The oil film I is retained there.

The recesses 25, 25a, 25b in FIG. 6 are one common ring whose projections 26, 26a, 26b are fixed to the piston 6! ! The structure is such that it can be mounted on the cable 35. The ring element 35 may be made in single or multiple pieces of metal or plastic material.

Needless to say, even in the structures shown in FIGS. 1 to 4, the distance between the side surfaces 29 and 30 of the recesses 25, 25a, and 25b may be reduced in order to create a capillary action. In this case insert 28 is not required. On the other hand, in the structure of FIGS. 5 and 6, it is also possible to provide a wide comb with a spacing between both sides 29, 30111 of the recesses 25.25a, 25b, and a suitable insert 28 therein. or,
In particular, when the recesses 25, 25a, and 25b are defined by 9111 minutes of rigidity, a structure in which the depths T of the recesses are all substantially the same is also possible.

Instead of a ring element 31 (FIG. 4) or 41 (FIG. 5) and a spacer ring 32.42 installed between them,
It is also possible to use a ring element 45 with a profile as shown in FIGS. This ring element 45 is provided with wave-like radial projections 46 which engage the opposite sides 29.30 of the respective recess.

That's where it stands out! 146^sa1] is the adjacent ring element 46
Determine the interval between. Other ring elements with circumferentially offset protrusions, for example in the form of corrugations or nipples, are also possible. The ring y1 element 47 of FIG. 9 is provided with a bottle-shaped spacer 48 or similar spacer.

Instead of steel wool, the insert 28 for collecting oil particles can also be made of glass fiber or other suitable, for example plastic, material. Particularly in the case of a structure with at least one recess defined by eleven rigid sections, the insert 28 can also be made of an oil-permeable ceramic material or of sintered metal.

[Brief explanation of the drawing]

1 is a partial elevational view in longitudinal section of an identical piston compressor according to the invention; FIG. 1a is an enlarged view of a detail of FIG. 1; FIGS. 2, 3, 4 and 5; 6 is an enlarged detailed view of a cylindrical piston compressor of a modified embodiment of the embodiment shown in FIG. 311, and FIG. 8 is a sectional view taken along the line ■--■ of FIG. 7, FIG. 9 is a view similar to FIG. 8 of another modified embodiment, and FIG. 10 is shown in FIG. 5. FIG. 8 is a detailed view similar to FIG. 8 of the part; 1... Crank case, 2... Crankshaft, 4... Connecting rod, 6... Piston, 6a... Guide part, 6b... Working part, 7... Cylinder, 10... Cylinder head, 15
... Compression chamber, 20... Wiper ring, 21... Leakage discharge chamber, 25,258° 25b -- Recessed part, 26.26a,
26b--Protrusion, 27... Edge, 28... Insert, 29° 30... Side, 31.35.41, 45.4
7...Ring element, 32.32a, 32b, 42.42
a, 42b, 46.48--Spacer.

Claims (10)

[Claims] (1) at least one piston (6) driven reciprocally within a cylinder (7) via a crankshaft (2) and a connecting rod (4);
) and guided in the cylinder part (7a) which is lubricated, and from which the diameter is reduced;
A dry working gas sealing part, in particular configured as a labyrinth piston, and a compression chamber (15) in said cylinder (7)
a working part (6b) defining a guide part (6b);
an oil wiper device (20) is provided in the movement area of a);
And outside the movement area of the work part (6b) in the cylinder (7), a leakage discharge chamber (21) is connected with a low pressure chamber.
) in a cylindrical piston compressor configured to discharge gas leaking from the compression chamber (15) and oil leaking from the crankcase (1). The leakage discharge chamber (21) at the dead center position
The part (A
), at least one recess (25, 25
a, 25b), and this recess is provided with the guide portion (6
A cylindrical piston compressor, characterized in that it collects the oil film traveling along the surface of a) and sends this collected oil to the leakage discharge chamber (21) and/or to the lubricating cylinder part (7a). . (2) the recess (25, 25a, 25b) has two substantially parallel sides (29, 30), of which at least the side (30) closer to the working part (6b); )
are provided on rib-shaped protrusions (26, 26a, 26b) that protrude from the periphery of the adjacent piston part (6c), which protrusions extend around the entire circumference and face the cylinder wall. A cylindrical piston compressor according to claim 1, characterized in that it is provided with sharp edges (27). (3) The side surface (29) of the recess (25, 25a, 25b)
, 30) are the longitudinal axis (
3. Cylindrical piston according to claim 2, characterized in that it is provided at an acute angle (α) to L), the apex (S) of said angle being oriented in the direction of said working part (6b). (4) the recess (25, 25a, 25b) comprises an insert (28) for temporarily storing collected oil particles;
4. The insert according to claim 1, wherein the insert is at least partially composed of a material capable of collecting oil particles in the form of separable oil droplets, such as steel wool. The cylindrical piston compressor described in . (5) Both sides (2) of the recess (25, 25a, 25b)
A cylindrical piston compressor according to claim 2 or 3, characterized in that the spacing between (9, 30) is small and that such a small spacing creates a capillary effect. (6) Claim characterized in that the projection (26, 26a, 26b) is formed by a wall section in the form of a strip that is elastically deformable during the forward and/or retractive movement of the piston. The cylindrical piston compressor according to any one of items 1 to 5. (7) The protrusions (26, 26a, 26b) are provided with ring elements (31, 35, 41) fitted onto the piston (6).
, 45, 47). The cylindrical piston compressor according to any one of claims 1 to 6, characterized in that it is formed by: , 45, 47). (8) The ring elements (31, 41) and the side surfaces (29, 30) of the recesses (25, 25a, 25b) facing thereto.
) at least one spacer element (32, 32a, 32b, 42, 42a) fitted on the piston (6) in the area of the recess (25, 25a, 25b).
, 42b). 8. The cylindrical piston compressor according to claim 7, characterized in that the compressor is regulated by the compressor. (9) The ring element (41, 45, 47) is connected to the side surface (29) of the recess (25, 25a, 25b) opposite thereto.
A cylindrical piston compressor according to claim 7 or 8, characterized in that the cylindrical piston compressor is constructed with local projections (46, 48) projecting towards the compressor. (10) At least two of the recesses (25, 25a, 25
b) are arranged successively in the stroke direction of the piston (6), the recesses (25a, 2
5b) is the recess (25) closer to the guide portion (6a).
, 25a), characterized in that it is configured to have a depth (T) greater than .
The cylindrical piston compressor described in .