JP2006312934A - Breakage protection device for radial compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a breakage protection device for a radial compressor of an exhaust gas turbo charger with which positional movement of an axial direction of a compressor housing member is bordered in a predetermined structure space even without correct knowledge of a working force. <P>SOLUTION: The breakage protection device of the compressor of the exhaust gas turbo charger has two inhibition elements 21, 31 which are separated sequentially, in other words, chronologically and spatially and work on each other in the case that a compressor impeller is damaged. An insertion wall 10 moves its position in the axial direction and an deterrence protruding part 11 engages in both the deterrence elements sequentially. Thus, energy is reduced step by step and the working force is prevented from rising to an uncontrollably high level at the same time. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The invention relates to a damage protection device for a radial compressor, as described in the superordinate features of claim 1, and to a radial compressor having such a damage protection device, and to an exhaust gas turbocharger. About.

  Radial compressors are incorporated in the exhaust gas turbocharger, and these radial compressors rotate at a high peripheral speed. Due to this, high kinetic energy is accumulated in the structural member. With increasing requirements on the exhaust gas turbocharger in terms of pressure behavior, the risk of compressor impeller failure as well is increased as a result of enormous centrifugal forces. In order to protect neither personnel nor valuables from danger, in the event of a compressor impeller breakage, any debris, along with the large kinetic energy of these debris, travels outward through the housing surrounding the impeller. It is required not to reach.

  WO 02/090722 (Patent Document 1) describes a breakage protection device for a radial turbocharger compressor, in which case the compressor impeller is fitted by a housing member. Surrounded, these housing members are in a state capable of containing the energy stored in the compressor impeller. This prevention of broken pieces that escape from the compressor housing is referred to as “containment”. In the event of a breakage of the compressor impeller, the housing member surrounding the compressor impeller, in particular the insertion wall of the compressor that bends the flow passage, has at least two parts, namely the axial flow direction to the radial flow direction. Separated into one radial portion within the region of inward flow diversion, as well as one axial annulus surrounding the inlet region upstream of the compressor impeller. A large part of the energy is relieved in the radial direction via forces acting on this insertion wall. When the compressor impeller is damaged, however, an axial force is also generated. This induces that the members of the compressor housing are moved in the axial direction in the direction of the compressor inlet. In order to prevent unacceptable position movements, common axially acting screw joints or shape-integral elements are used. The breakage protection device known from WO 02/090722 (Patent Document 1) has a braking device, which acts on a housing member that moves in the axial direction and brakes. multiply. The insertion wall is then braked on one rib of the compressor housing intermediate wall or simultaneously on a number of ribs.

Since the forces acting in the case of breakage are not precisely known, precise sizing of the braking element that acts on the structural members and should be restrained in the axial direction is not an easy task. If these elements are oversized, an excessively high force that cannot be suppressed can occur. If these elements, on the contrary, are undersized, the deterrent action is not sufficient to prevent the individual compressor impeller members from coming out of the housing in the axial direction.
International Publication No. 02/090722 Pamphlet

  Accordingly, the problem of the present invention is that with the damage protection device, the axial movement of the compressor housing member can be limited in a predetermined structural space without an accurate knowledge of the acting force. It is to provide a damage protection device for a radial compressor of an exhaust gas turbocharger.

  This problem is solved by a damage protection device for a turbocharger radial compressor according to the features of claim 1.

  According to the present invention, this object is achieved by the fact that two or a number of deterrence measures become getrennt interacting in sequence, ie in time series and space. This reduces the energy step by step and at the same time prevents the acting force from rising to an uncontrollable high level.

  When the first restraining element is overcome, the axial annulus separated from the remaining insertion wall is positioned away from the turbine shaft in the axial direction until the second restraining element is engaged. Moving.

  The moved insertion wall has enough space to move in the axial direction after the engagement of the first deterrent element and before the second deterrent element is engaged. Yes. Thus, there is sufficient space inside the compressor housing to mitigate the kinetic energy of the damaged compressor impeller.

  If necessary, a third or further restraining element can be engaged.

  A turbocharger according to the present invention comprising a radial compressor according to the present invention having the above-described damage protection device is provided for personnel involved in the turbocharger and adjacent equipment in the event of a compressor impeller failure. It embodies relatively little danger.

  Further advantages are given by the dependent claims.

  Next, the damage protection device of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a cross section of a compressor of an exhaust gas turbocharger. The flow of air to be compressed is indicated by arrows in the figure. These indications relate to this flow process upstream and downstream. As indicated by the broken line, the compressor impeller 60 is provided on the rotation axis A, and the compressor impeller is surrounded by various housing members. These representations are related to this axis of rotation A in the radial, axial and coaxial directions.

  Immediately in the radial direction, an insertion wall 10 is provided on the compressor impeller and outside the flow passage 40 leading through the compressor impeller. The insertion wall 10 radially bounds the flow passage, and from the upstream side of the compressor impeller, depending on the respective manner of fixation of the insertion wall 10 to the outer housing member. The compressor impeller 60 is passed to the area of the diffuser provided on the downstream side of the compressor impeller. In the radial direction, outside the insertion wall, an outer compressor housing wall 20 is provided, through which a filter silencer, for example for supplying air to be compressed, is provided. 50 or an intake connection pipe is fixed to the compressor housing. The compressor housing wall 20 is connected to the insertion wall 10 in the area of the diffuser, either directly or via another housing member.

  The damage protection device according to the invention should axially brake the insert wall 10 separated in the region of the compressor impeller in the event of a breakage of the compressor impeller 60 and, therefore, the compressor Axial outflow from the housing should be prevented. For this purpose, a constraining protrusion 11 is provided along the insertion wall 10 which is provided coaxially and projects outward in the radial direction, and this constraining protrusion is provided on the compressor impeller. Should it break, it should cooperate with the braking element. These braking elements are formed as annular-shaped restraining elements 31 and 21 formed with a central opening. The first restraining element 31 is fixed to an intermediate wall 30 provided between the insertion wall 10 and the compressor housing wall 20. This first deterrent element 31 is in direct contact with the depressing protrusion of the insertion wall in the embodiment according to FIG. 1, so that in the event of a breakage of the compressor impeller, this insert wall is directly Thus, the insertion wall is braked once in the axial movement. The restraining protrusion and restraining element are connected to each other via a screw joint, with a flange, or a wedge surface that rides on each other. Alternatively, it is possible that there is likewise only a slight axial spacing between the restraining protrusion and the first restraining element 31. In this case, the first braking stage of the breakage protection device grips for the first time after the insertion wall has just been displaced in the axial direction. In this embodiment, the first blow that normally induces the above-mentioned breakage of the insertion wall does not directly affect the braking device, and the first deterrent element 31 directly. Has the advantage of damaging.

  The second suppression element 21 is provided in a state of being displaced in the axial direction with respect to the first suppression element 31. The second restraining element comprises an annular body having a central opening provided coaxially and extending around. The annular body extending around the periphery is a boundary of the support wall 22 radially inward, and the support wall is fixed to the outer wall 20. The support wall is corrugated for additional reinforcement as shown in FIG.

The relative dimensions of the restraining protrusion 11 and restraining elements 21 and 31 can be explained based on the schematic illustration in FIG. The inhibiting protrusion has a maximum outer radius R _11. The maximum outer radius R ₁₁ represents the greatest radius of the deterrent protrusion provided coaxially. If the restraining protrusion is provided with a wedge surface as shown in this figure, this maximum outer radius R11 is the radius of the outermost wedge tip. These deterrent elements 21 or 31 have the smallest inner radius R ₂₁ or R ₃₁ . This minimum inner radius indicates the smallest radius of the opening in each of these restraining elements. If the openings of these deterrent elements are provided with a wedge surface, as shown in this figure, this minimum radius is the radius of the innermost wedge tip or the coaxially provided opening. The narrowest position.

In order for the restraining protrusion to be able to cooperate with the restraining element, the largest outer radius R ₁₁ must be larger than the smallest inner radii R ₂₁ and R ₃₁ . Therefore, it is simply ensured that this depressing protrusion can brake the insertion wall by engagement into the depressing protrusion on the axial path. In an advantageous manner, the opening radius of the second restraining element 21, ie the smallest inner radius R _21, is smaller than the opening radius of the first restraining element 31, ie the smallest inner radius R ₃₁ . If the restraining protrusion 11 is to be reduced to the dimension of the opening of the restraining element 31, that is, the smallest inner radius R _31, at the thickest position when penetrating the first restraining element 31, Thanks to the smaller opening radius, the second deterrent element nevertheless hinders the depressing protrusion 11 and can therefore exert the braking action of this second deterrent element.

  The restraining protrusion 11 is basically formed as a cylindrical, annular body extending around the periphery. Optionally, this restraining protrusion can also be divided into two or a number of parts along the outer periphery, thus acting on this restraining protrusion in the event of a compressor impeller failure. Force and the stress induced thereby cannot be spread over the entire circumference.

  If necessary, a third or further deterrent element can be provided, which can be in the region between the first and second deterrent element or this second deterrent element. Located further upstream of the deterrent element.

1 is a cross-sectional view of a compressor housing of an exhaust gas turbocharger having a damage protection device according to the present invention. FIG. 2 is a schematic enlarged view of the damage protection device according to the invention according to FIG.

Explanation of symbols

10 Insert wall 11 rotation axis R ₁₁ deterrence deterrent protrusion 20 compressor housing outer wall 21 inhibiting element 22 the support wall 30 compressor housing intermediate wall 31 inhibiting element 40 flow passage 50 inlet housing 60 compressor wheel A compressor wheel Maximum outer radius of protrusion R ₂₁ , Minimum inner radius of R ₃₁ deterrent element

Claims (10)

This is a damage protection device for a turbocharger radial compressor.
A compressor housing-insertion wall (10) that radially bounds the flow passage (40) across the rotor blades of the compressor impeller, and
A compressor housing-outer wall (20), which radially surrounds the insertion wall (10),
A depressing protrusion (11) is provided along the insertion wall (10) that protrudes radially outward, and
Between the insertion wall and the outer wall, there are at least two axially offset deterrent elements (21, 31) imparting an annularly shaped opening, the axis of the insertion wall (10) In the above-mentioned breakage protection device of the style provided for deterring the depressing projection (11) of this insertion wall when moving the position in the direction,
Both deterring elements (21, 31), in turn, cooperate with the depressing protrusions (11) of the insertion wall as they move in the axial position of the insertion wall (10). A damage protection device, characterized in that it is provided in a state of being separated from each other.   2. Damage protection device according to claim 1, characterized in that both deterrent elements (21, 31) are fixed along the compressor housing in a mutually separated state.   3. The damage protection device according to claim 2, wherein both deterrent elements (21, 31) are fixed along the compressor housing in an axially separated state.   The first deterrent element (31) is part of an intermediate wall (30) provided between the insertion wall (10) and the outer wall (20) of the compressor housing. Or the damage protection apparatus of 3.   The second deterrent element (21) is fixed along the outer wall (20) of the compressor housing and is part of a support wall (22) guided radially inward The breakage protection device according to any one of claims 2 to 4.   6. The damage protection device according to claim 5, wherein the support wall (22) is formed in a waveform in the outer peripheral direction. The restraining element (21, 31) bounds the annular shaped opening, and
The restraining protrusion (11) has the largest outer radius (R ₁₁ ), which is the smallest inner radius (R) of both annular shaped openings bounded by these restraining elements. ₂₁ , R ₃₁ )
The breakage protection device according to any one of claims 1 to 6. The minimum inner radius R ₂₁ of the opening of the deterrent element provided on the upstream side further to claim 7, characterized in that it is configured to be less than the smallest inner radius R ₃₁ of the other suppression element Damage protection device as described.   A radial compressor comprising the damage protection device according to any one of claims 1 to 8.   An exhaust gas turbocharger comprising the radial compressor according to claim 9.

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