DE102006030493B4 - Compressor crankshaft, in particular refrigerant compressor crankshaft, and method for its production - Google Patents

Abstract

A compressor crankshaft having a shaft member, a crankpin eccentric to the shaft member, a transition element between the shaft member and the crankpin, and a counterweight attached to the transition member, the counterweight being configured to engage the transition member in a predetermined positioning range in any radial position to be connected, characterized in that the counterweight (6) and the transition element (4) are connected to each other without auxiliary joining parts by the counterweight (6) is formed or formed in a partial area, wherein a connection between the counterweight (6) and the Transition element (4) is possible without concrete positions on the counterweight (6) must be prepared for that at the transition element (4) at least one Befestigungsausformung is provided with the counterweight (6) is pressed, that the Befestigungsausformung as a mounting recess (11 ) educated is, in which a part (16) of the counterweight (6) is pressed, and in that the fastening recess (11) in a region remote from the counterweight (6) has a cross-sectional widening (19).

Description

The invention relates to a compressor crankshaft, according to the preamble of claim 1.

Furthermore, the invention relates to a method for producing a compressor crankshaft according to the preamble of claim 8.

Such a crankshaft is for example off EP 0 558 806 A1 known. Here the counterweight is attached directly to the crank pin.

Such a crankshaft serves to convert a rotary motion of a drive motor into a reciprocating motion of a piston. When the shaft member of the crankshaft rotates, then the crankpin performs an orbiting motion about the axis of the shaft member. This results in unevenly distributed forces that can lead to a troubled run of such a compressor. It is therefore known to provide the crankshaft with a counterweight, which is usually arranged on the crank pin opposite side of the axis of the shaft member. In many cases, the counterweight is connected to the transition element.

Another crankshaft is for example off US Pat. No. 3,587,343 known. Here, the counterweight is attached by means of rivets to a disc which is rotatably connected to the crankshaft. So you have to provide both this disc and the counterweight with at least one hole that fits the rivets.

JP 2000-213 462 A shows a refrigerant compressor with a counterweight which is fixed to the upper end of the crankshaft. This counterweight can be provided with one or more balancing elements, which are also secured by rivets on the counterweight.

DE 195 16 811 C2 shows a relatively massive crankshaft to the transition element, a counterweight is attached by means of rivets.

Instead of rivets, screws are also used to attach a counterweight to the transition element, see for example US 4 406 590 A or US Pat. No. 6,287,092 B1 , In the latter case, the counterweight is screwed into the crankpin and protrudes from the crankpin in the direction of the crankshaft.

In US Pat. No. 1,261,527 A is disclosed a crankshaft with counterweights. The counterweights are attached to the crankshaft via threaded rods. With the help of nuts, the distance between counterweight and crankshaft can be adjusted.

In GB 1 016 926 A a crankshaft is proposed in which a counterweight can be fixed in different angular positions on the crankshaft.

In US 4,785,772 A Another crankshaft is proposed in which holes are provided in the crank webs. In the holes inserts of heavy metal are attached.

In US 1 908 071 A a crankshaft is proposed in which counterweights are riveted to the crank webs.

In US Pat. No. 6,287,092 B1 a compressor arrangement is proposed in which a counterweight is provided on the crankshaft. The counterweight consists of a stamped sheet metal part, which is preferably superimposed two-ply.

In all cases, it is in principle required that both the crankshaft or the transition element on the one hand and the counterweight on the other hand are provided at a predetermined position with a bore, so that a Hilfsfügeteil, such as screw or rivet, can be passed to the counterweight and the Connecting transition element together.

Refrigerant compressors are basically mass-produced articles that are produced in large quantities. However, different components are required for different capacities or sizes of the refrigerant compressors. These must be manufactured and stored. This leads to increased production costs.

An object of the invention is to keep the production costs low.

This object is achieved in a crankshaft of the type mentioned above in that the counterweight in a predetermined positioning range in each radial position with the transition element is connectable.

With this configuration, it is possible to use a single type of counterweight for different compressors. The balancing of the individual crankshafts is then carried out simply by mounting the counterweight at different distances from the crankshaft axis. Basically, there are few prerequisites for this. On the one hand, the counterweight on the one hand and the transition element on the other must fit together in different positions. This can be realized, for example, in that in the possible overlap area between Counterweight and transition element planar surfaces are provided on counterweight and transition element. On the other hand, a link between the counterweight and the transitional element must be possible everywhere, without having to prepare specific positions.

According to the invention it is provided that the counterweight and the transition element are connected to each other without auxiliary joining parts. This saves additional effort for keeping ready and supplying the auxiliary joining parts. It must also be produced no holes and the like for auxiliary joining parts, which later must match at counterweight and transition element. Possible types of connection are welding, soldering, gluing or the like.

According to the invention it is provided that at least one Befestigungsausformung is provided at the transition element, with which the counterweight is pressed. To connect the counterweight with the transition element so the counterweight is formed or reshaped in a partial area. By providing the mounting formation on the transition element, one can use the same mounting device for all possible counterweight positions. Namely, this device will deform the counterweight always at the same position relative to the transition element, for example by pressing, so that many different types of crankshafts can be manufactured in this way. In addition, the design of the press connection between transition element and counterweight has the advantage that even those parts can be connected to each other, which are otherwise difficult to connect due to their materials or surface treatments, e.g. by welding, soldering, gluing or similar

According to the Befestigungsausformung is formed as a recess into which a part of the counterweight is pressed. The counterweight, which is initially flat on the abutting side of the transition element, is then locally deformed to have a projection which is pressed into the Befestigungsausformung. This makes it possible to realize a sufficient connection between the counterweight and the transition element.

Preferably, the mounting recess extends through the transition element. In the simplest case, the mounting recess is thus formed as a through hole. This has the advantage that one can work with a counter-holder to act from the opposite side of the counterweight of the transition element from the part of the counterweight, which is deformed into the mounting recess. So you can always, if it makes sense, the projection of the counterweight that has been deformed into the mounting recess compress. This leads to a certain tension of this projection in the radial direction relative to the transition element.

According to the invention, the fastening recess has a cross-sectional widening in a region remote from the counterweight. In particular, when acting with a tool on the resulting projection, which is deformed by pressing into the mounting recess, you can ensure that this projection in the cross-sectional widening also widen, so that a kind of rivet connection is created. However, this rivet connection does not require any auxiliary joining parts, because the corresponding material content originates from the counterweight itself.

Preferably, the cross-sectional widening has an oblique surface. If you use a hole, then this inclined surface is part of a cone shell surface. Such an inclined surface allows a flush abutment of the material of the counterweight, which has been displaced in the mounting recess, to the inner wall of the mounting recess.

Preferably, the fastening recess has a circular cross-section. Thus, the mounting recess can be relatively easily produced, for example by drilling.

In an alternative embodiment, it can be provided that the fastening recess has an anti-rotation form. Such an anti-rotation form can be realized in many ways. For example, one can use a polygonal cross-section. It is also possible to use a cross section whose edge is jagged. It is also possible to use an oval shape or simply a shape that otherwise deviates from a circular shape.

Preferably, the counterweight is formed as a sheet metal element. Such a sheet metal element is in many cases in the production of a refrigerant compressor anyway, for example, in the production of the capsule. A sheet metal element with a thickness in the range of 2 to 6 mm can still deform sufficiently, but on the other hand, on the other hand, a sufficiently large mass in order to fulfill the function of a counterweight can. If larger balancing weights are required, a second (possibly also another) sheet metal element can be placed on the first sheet metal element connected to the transition element. The connection between the first and second Sheet metal element can then be advantageously carried out on the freely projecting over the transition element areas of the sheet metal elements, for example, in turn by a press connection.

The object is achieved in a method of the type mentioned above by using the same counterweight for different crankshafts, positioned the counterweight on the transition element in a suitable for each crankshaft radial mounting location and connects in this mounting the counterweight with the transition element.

As described above in connection with the crankshaft, this creates the possibility of using the same counterweight for different types of crankshaft. The adjustment of the counterweight to a particular type of crankshaft is made simply by positioning the counterweight in a distance from the axis of rotation of the crankshaft that fits the crankshaft. In this position, the counterweight can then be connected to the transition element.

It is preferred that one deforms the counterweight in the installation. By deforming the counterweight, this deformation can be used to establish a connection between the counterweight and the transition element. In this case, it is both possible to deform the counterweight into the transition element, for example by forming a projection, which then projects into the transition element, as well as deforming the counterweight around a corresponding projection on the transition element. In both cases you get a sufficiently strong connection between the counterweight and the transition element.

Preferably, a part of the counterweight is deformed by means of a punch into a fastening recess in the transition element. If you have positioned the counterweight in the correct position on the transition element, then it is sufficient to push in with a stamp in the counterweight and that of the transition element facing away from the transition element and in this deformation process then material of the counterweight is pushed out of the transition element facing side and Although in the mounting recess, so that you get by forming the counterweight a sufficient connection between the counterweight and the transition element.

Preferably, on the side facing away from the counterweight of the transition element assigns a counter-holder, which acts on the counterweight. Thus, the force applied during pressing is absorbed by the counter-holder, so that the loads that could act on a connection between the transition element and the shaft element are kept small. It may also be possible to ensure that the counterpart part of the counterweight, which is pressed through the transition element, deformed in the manner of a rivet, so as to achieve a high-strength connection between the counterweight and the transition element.

Preferably, the counter-holder is guided from the side facing away from the counterweight into the fastening recess. In this case, it is ensured that the part of the counterweight, which has penetrated into the mounting recess, is compressed. In this case, there is not only a positive connection between the counterweight and the transition element, but the part of the counterweight that has been displaced into the mounting recess, stuck with a considerable friction on the inner wall of the mounting recess.

• 1 eine perspektivische Darstellung einer Kurbelwelle,
• 2 die Kurbelwelle im schematischen Querschnitt vor der Befestigung eines Gegengewichts am Übergangselement,
• 3 die Darstellung der 2 nach der Befestigung des Gegengewichts,
• 4 einen vergrößerten Ausschnitt aus 3,
• 5 eine gegenüber 4 abgewandelte Ausführungsform der Verbindung,
• 6 eine Draufsicht auf eine erste Ausgestaltung eines Übergangselements,
• 7 eine Draufsicht auf eine zweite Ausgestaltung eines Übergangselements und
• 8 eine Draufsicht auf eine dritte Ausgestaltung eines Übergangselements.

It is also preferred if the part of the counterweight pressed into the fastening recess is spread open. It is particularly advantageous if the mounting recess has a corresponding cross-sectional widening. In this case, the counterweight is held virtually captive on the transition element.
The invention will be described in more detail below with reference to preferred embodiments in conjunction with the drawing. Herein show:

• 1 a perspective view of a crankshaft,
• 2 the crankshaft in schematic cross section before the attachment of a counterweight to the transition element,
• 3 the representation of 2 after fixing the counterweight,
• 4 an enlarged section 3 .
• 5 one opposite 4 modified embodiment of the compound,
• 6 a top view of a first embodiment of a transition element,
• 7 a plan view of a second embodiment of a transition element and
• 8th a plan view of a third embodiment of a transition element.

1 shows a crankshaft 1 with a shaft element 2 a crankpin 3 and one Transition element 4 that is between the shaft element 2 and the crankpin 3 is arranged.
The wave element 2 and the crankpin 3 can be designed as deep-drawn sheet metal parts. The wave element 2 may optionally also consist of several sections which are telescoped into each other. The transition element 4 is preferably formed as a sintered component. It is also possible to have such a transition element 4 to produce by extrusion, in particular cold extrusion.

The transition element 4 has on the side facing away from the shaft element a recess 5 on, in the crankpin 3 is mounted.

At the transition element 4 is a counterweight 6 attached. The counterweight 6 For example, is formed of sheet steel with a thickness of about 3 mm. It consists in principle of a flat plate, which is designed as a simple stamped part. Such a stamped part can be obtained from stamping residues in the manufacture of a capsule of a refrigerant compressor, for which the crankshaft 1 is provided.

On the counterweight 6 is a point of impressions 7 recognizable, its production in conjunction with the 2 to 4 is explained in more detail.

2 shows the crankshaft 1 out 1 schematically in cross section. The counterweight 6 is on the the shaft element 2 opposite side of the transition element 4 it is obvious that the transition element 4 here a flat bearing surface 8th having. The counterweight 6 has an equally flat lying surface 9 on, giving you the counterweight 6 on the transitional element 4 can move in the radial direction. In a certain range is therefore a positioning of the counterweight 6 on the transition element 4 possible in every position. The displaceability is indicated by a double arrow 10 symbolizes.

In the area where the counterweight 6 on the transition element 4 rests, the transition element has 4 a mounting recess 11 on, which is formed in the present case as a through hole.

If now the counterweight 6 in the right position on the transition element 4 has been positioned, then you can do the counterweight 6 in this position with the transition element 4 connect. This is schematically in 3 shown. A counterholder 12 that on a basis 13 is arranged by the the wave element 2 facing side into the mounting recess 11 introduced to a certain depth, for example, 1/2 to 1/3 of the thickness of the transition element 4 can amount. As the mounting recess 11 at all crankshafts 1 Whatever its type is at the same position, it is relatively easy to use the backstop 12 position accordingly.

You then press with a stamp 14 that of an actuator 15 is driven by the shaft element 2 facing away from the counterweight 6 , The Stamp 14 can and should preferably have a cross section which is smaller than the cross section of the mounting recess 11 , In this pressing process is the counterweight 6 deformed. This material is displaced to where it can escape. So there is a head start 16 within the mounting recess 11 , If the material of the counterweight 6 far enough into the mounting recess 11 has penetrated, it comes to rest on the anvil 12 , The material and thus the lead 16 is compressed so that the lead 16 radially from the inside with a certain pressure on the inner wall of the mounting recess 11 invests. This is a sufficiently stable connection between the counterweight 6 and the transition element 4 created.

Of course, it is also possible to employ the illustrated one fastening recess, which in many cases will suffice to provide two or more fastening recesses in which the fastening operation between the transition element 4 and the counterweight 6 done in a similar manner.

The finished connection between the counterweight 6 and the transition element 4 is in 4 shown. The Stamp 14 has the point of impressions 7 in the counterweight 6 leave. The counterpart 12 has, like this through conical surfaces 17 implied, made sure that the lead 16 against the inner wall 18 the mounting recess 11 has been pressed. In the execution of the transition element 4 As a sintered part can be a certain deformation of the inner wall 18 take place in the radial direction. This further increases the stability of the compound.

5 shows an embodiment in which the mounting recess 11 a detail extension 19 which has an inclined surface 20 merges into the cross section, which is on the counterweight 6 facing side of the transition element 4 shows. If now the material of the counterweight 6 in the mounting recess 11 is pushed into it and there the lead 16 forms, then the counterpart can 12 Make sure that this material is spread so that the lead 16 , more precisely its an end 21 , along with the counterweight 6 forms a kind of riveted joint, which is the counterweight 6 at the transition element 4 holds. However, an auxiliary joining part, such as a separate rivet or a screw, are not required for the attachment.

When the mounting recess 11 is formed as a cylindrical bore, then the inclined surface 20 formed as part of a conical surface. The same applies in a transferring manner, when the mounting recess 11 has a cross section that deviates from the circular shape.

The 6 to 8th now show different transition elements 4 with different shapes of the mounting recess 11 ,

6 shows a mounting recess 11 with a circular cross-section.

7 shows a mounting recess 11 with an approximately square cross section.

8th shows a mounting recess 11 that basically has a circular shape, with the circumference of the circle being serrated or toothed. The execution after 7 and 8th increase the resistance against twisting of the counterweight 6 , It can be the same press stamp 14 for generating the indentation point 7 used as in the embodiment according to 6 ,

For the sake of completeness, it should be noted that in the presentation of the 6 to 8th that the transition element of the the shaft element 2 facing away from the crank pin show, also an oil supply opening 21 can recognize, by the oil from an oil channel 22 and an oil transport passage 23 in the interior of the crankpin 3 can get. From there, the oil comes through openings 24 . 25 in areas where it can be used for lubrication or oil cooling. There is also a vent passage 26 to recognize that in a vent 27 ends.

Claims (13)

A compressor crankshaft having a shaft member, a crankpin eccentric to the shaft member, a transition element between the shaft member and the crankpin, and a counterweight attached to the transition member, the counterweight being configured to engage the transition member in a predetermined positioning range in any radial position to be connected, characterized in that the counterweight (6) and the transition element (4) are connected to each other without auxiliary joining parts by the counterweight (6) is formed or formed in a partial area, wherein a connection between the counterweight (6) and the Transition element (4) is possible without concrete positions on the counterweight (6) must be prepared for that at the transition element (4) at least one Befestigungsausformung is provided with the counterweight (6) is pressed, that the Befestigungsausformung as a mounting recess (11 ) train t, in which a part (16) of the counterweight (6) is pressed, and in that the fastening recess (11) has a cross-sectional enlargement (19) in a region remote from the counterweight (6). Compressor crankshaft after Claim 1 , characterized in that the fastening recess (11) passes through the transition element (4). Compressor crankshaft after Claim 2 , characterized in that the cross-sectional widening (19) has an inclined surface (20). Compressor crankshaft after one of Claims 1 to 3 , characterized in that the fastening recess (11) has a circular cross-section. Compressor crankshaft after one of Claims 1 to 3 , characterized in that the fastening recess (11) has an anti-rotation. Compressor crankshaft after one of Claims 1 to 5 , characterized in that the counterweight (6) is designed as a sheet metal element. Compressor crankshaft after one of Claims 1 to 6 characterized in that the compressor crankshaft is a refrigerant compressor crankshaft. A method for producing compressor crankshafts, in which counterweights are attached to transition elements, which transition elements are each arranged between a shaft member and a crank pin, characterized in that for different crankshafts the same counterweight is used, the counterweight in an overlap region between counterweight and transition element is applied to the transition element, the counterweight is positioned at the transition element in the appropriate crankshaft radial mounting location by the counterweight on the transition element is displaced in the radial direction, and in this mounting the counterweight is connected to the transition element by the counterweight in the installation site deformed is so that it has a projection which is pressed into a Befestigungsausformung the transition element. Method according to Claim 8 , characterized in that a part of the counterweight is deformed by means of a punch into a recess in the transition element into it. Method according to Claim 9 , characterized in that on the side facing away from the counterweight of the transition element, a counter-holder is arranged, which acts on the counterweight. Method according to Claim 10 , characterized in that the counter-holder is introduced from the side facing away from the counterweight in the mounting recess. Method according to Claim 11 , characterized in that the pressed-in in the mounting recess part of the counterweight is spread. Method according to one of Claims 8 to 12 , characterized in that it is a refrigerant compressor crankshaft.

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