EP1165963A1

EP1165963A1 - Refrigerant compressor

Info

Publication number: EP1165963A1
Application number: EP01911527A
Authority: EP
Inventors: Günter DITTRICH
Original assignee: Bitzer Kuehlmaschinenbau GmbH and Co KG
Current assignee: Bitzer Kuehlmaschinenbau GmbH and Co KG
Priority date: 2000-01-29
Filing date: 2001-01-25
Publication date: 2002-01-02
Anticipated expiration: 2021-01-25
Also published as: DK1165963T3; CN1363018A; US6568921B2; WO2001055594A1; US20020062657A1; DE10003882C2; DE50114814D1; ATE428052T1; CN1114760C; EP1165963B1; DE10003882A1; ES2322430T3

Abstract

The compressor includes a pressure chamber (38) downstream of a cylinder chamber, and a damper channel (60) between two channel ends (64, 66) via which compressed refrigerant flows into the discharge channel (80). The damper channel has an inlet aperture (74) between the two ends of the damper channel

Description

Refrigerant compressor

The invention relates to a refrigerant compressor, comprising a compressor housing, at least one cylinder chamber arranged in the compressor housing, a piston oscillating in the cylinder chamber, a suction chamber upstream of the cylinder chamber, from which refrigerant enters the cylinder chamber, and a pressure chamber downstream of the cylinder chamber, in which in the Compressed refrigerant cylinder chamber enters, a damper channel extending between a first end and a second end, via which compressed refrigerant flows from the pressure chamber into an outlet channel.

Such a refrigerant compressor is known for example from EP 0 926 343.

In this refrigerant compressor, the entire damper duct is flowed through in one direction, with satisfactory damping being achieved, but with a considerable space requirement due to the length of the damper duct through which flow passes.

However, the invention is based on the object of further optimizing such a refrigerant compressor with regard to the damping of pulsations and the space requirement.

This object is achieved according to the invention in a refrigerant compressor of the type described in the introduction in that the damper channel has an inlet opening located between the first end and the second end. The solution according to the invention makes it possible to further optimize the damping of pulsations in refrigerant compressors, namely in that a pressure wave entering the damper channel spreads from the inlet opening both in the direction of the first and in the direction of the second end and then by reflections At both ends of the damper channel, the damping of pulsations takes place even better.

There is also the possibility of arranging such a damper channel in a space-optimized manner.

The outlet opening can, in principle, be arranged at a wide variety of locations on the damper channel. A particularly favorable solution provides that the outlet opening lies in the region of one of the ends, so that compressed refrigerant flows through the damper channel insofar as it is guided from the inlet opening to the outlet opening in the region of one of the ends.

With regard to the implementation of the damper channel with regard to the provision of outlet openings, a particularly favorable solution provides that the damper channel has two outlet openings in addition to the inlet opening and that at least one of the outlet openings forms the outlet opening. This solution is structurally particularly simple to implement, in particular even if the mouth openings are arranged in the region of opposite ends.

With regard to the use of the damper duct according to the invention, the most varied of possibilities are conceivable. One possibility would be to design the damper channel so that the compressed refrigerant flows through "the inlet opening into the damper duct and then flows towards both ends towards the respective outlet openings.

As an alternative to the above solution or in addition to this, a solution which is particularly advantageous in terms of its damping effect provides that the damper channel extending between the ends has a section through which the compressed refrigerant flows and an acoustically blind section, i.e. a section with reflection at the acoustically closed end , wherein, in particular, the acoustically blind-closed section of the damper channel makes a notable contribution to damping pulsations or pressure waves, since this reflects a pressure wave, which in turn is then superimposed in the damper channel with pressure waves subsequently entering through the inlet opening.

In particular, an acoustically blind section is formed so that there is an opening or a gap through which oil can flow out, so that oil accumulations are avoided.

With regard to the arrangement of the two sections relative to one another, the most varied of possibilities would be conceivable, for example it would be conceivable that the acoustically blind section of the damper duct connects to the outlet opening, so that a pressure wave entering the damper duct first migrates from the inlet opening to the outlet opening and then a part of it does not leave the damper channel through the outlet opening, but continues to spread out in the acoustically blind section starting from the outlet opening. Another solution which is even more advantageous with regard to the damping effect provides that the section through which the refrigerant flows and the acoustically blind-closed section of the damper channel extend away from the inlet opening, so that the pressure wave entering the damper channel through the inlet opening divides the acoustically blindly Section and in the section through which the refrigerant flows.

It is particularly advantageous if the section through which the refrigerant flows and the section closed acoustically blind extend in opposite directions away from the inlet opening, so that, in particular, reflections in the section closed off acoustically blind can spread immediately further into the section through which the coolant flows.

So far, no information has been given regarding the position of the inlet opening. In principle, it would be conceivable to provide the inlet opening anywhere between the first end and the second end. A particularly favorable solution provides that the inlet opening lies in the region of a central section of the damper duct, preferably in the region of approximately half the total length of the damper duct, so that an incoming pressure wave is distributed over two sections of approximately the same length.

With regard to the specific embodiment of the damper channel, no further details have been given in connection with the previous exemplary embodiments. An advantageous exemplary embodiment provides that the damper channel in a part that can be mounted on the compressor housing is arranged and that the part can be mounted on the compressor housing in such a way that either the mouth opening arranged at the first end or the mouth opening arranged at the second end serves as an outlet opening and leads into the outlet channel provided, for example, in the compressor housing.

With regard to the respective other orifice opening, it would be conceivable, for example, that this still leads into an additional section of the damper channel, for example running in the compressor housing, which ends acoustically blind somewhere in the compressor housing. This would open up the possibility of additionally extending the damper channel by a further section.

It is structurally particularly favorable, however, if the mouth opening which does not open into the intended outlet channel is acoustically blind.

Such an acoustically blind closure of the mouth opening could be done, for example, by an inserted or screwed plug.

However, it is particularly expedient if the mouth opening is closed by a region of the part which carries the part which can be mounted on the compressor housing.

In the simplest case, the part that can be mounted on the compressor housing is the valve plate carried by a crankcase of the compressor housing, which closes it with a region that covers the opening. With regard to the part which has the damper channel and can be mounted on the compressor housing, no further details have been given. So this could be a separate part that is completely independent of the usual parts of the compressor housing and is used as a separate insert in each case, for example in the assembly of the cylinder head.

However, it is particularly expedient if the damper channel runs in the cylinder head and thus the cylinder head forms the part which has the damper channel and can be mounted on the compressor housing.

An element forming the damper channel, for example a damper tube, can also be inserted into the cylinder head. However, it is particularly advantageous if the damper channel is molded into the cylinder head, that is to say, for example, if the cylinder head is designed as a casting, the damper channel is provided in this casting. Alternatively, it would also be conceivable to implement the damper channel as a bore to be provided in the cylinder head.

With regard to the course of the damper channel in the cylinder head, no further details have so far been given either.

A particularly space-saving, advantageous solution provides for the damper duct to run with a section in an area approximately parallel to a cylinder head cover of the cylinder head, that is to say that the damper duct, which is preferably used for damping pulsations certain frequency components must have a corresponding length, can advantageously be of sufficient length due to its extension in this area, without the cylinder head being significantly larger.

Furthermore, it is preferably provided that the damper channel extends with an essential portion in the direction of a crankshaft and thus preferably also runs in the direction in which the cylinders are arranged in succession in a multi-cylinder refrigerant compressor.

With regard to the arrangement of the damper channel relative to the pressure chamber, no further details have also been given so far. A particularly favorable solution provides for the damper duct to run on a side of the pressure chamber facing away from the cylinder chambers, since this makes it possible, for example, to have the damper duct run along the cylinder head cover, for example molded onto it or molded into it.

In order to achieve a suitable position of the orifices of the damper channel, it is preferably provided that the damper channel has end regions running in the direction of a crankcase, so that these end regions can then be opened in a simple manner with orifices that are accessible in the region of the crankcase and are preferably accessible via the crankcase can be provided.

For example, the mouth openings of the damper channel face the crankcase. A particularly favorable solution provides that the orifices of the damper channel in a bearing surface of the cylinder head lie and thus, for example, by placing the cylinder head on the rest of the compressor housing, a seal in the area of the orifices can be realized in a simple manner.

It is particularly advantageous if the orifices are sealed in the same way as the cylinder head in the area of its bearing surface.

In order to obtain the best possible reflection and decoupling at the outlet opening and the inlet opening, it is preferably provided that the inlet opening of the damper channel opens into the pressure chamber with a cross-sectional jump and that the outlet opening of the damper channel opens into the outlet channel with a cross-sectional jump.

The size of the cross-sectional jumps is preferably such that the cross-sectional jump between the damper duct and the outlet duct is at least a factor of 2 or 3, in which case a cross-sectional jump takes place from a small cross-section, namely the outlet opening, to a large cross-section, namely that of the outlet duct ,

It is even better if the cross-sectional jump is at least a factor of 5.

Furthermore, the decoupling between the damper duct and the pressure chamber is also favored in that the cross-sectional jump between the damper duct and the pressure chamber is at least a factor of 3, better still a factor of 5, in which case a cross-sectional jump from the large cross-section of the pressure chamber to a cross section that is smaller by a factor of 3 or 5, namely that of the inlet opening of the damper channel.

It is even better if this cross-sectional jump is even larger.

With regard to the type of damper channel, no further details have been given in connection with the previous explanation of the individual exemplary embodiments. For example, it is conceivable to design the damper duct as a duct with a constant cross section.

Alternatively or in addition to this, it is also conceivable to provide the damper channel with cross-sectional constrictions, for example produced by diaphragms, in order to further increase the damping effect, so that the damper channel has different cross sections at different points in the longitudinal direction.

The cross-sectional constrictions and the cross-sectional enlargements can be arranged in each section of the damper channel. For example, in the section through which the refrigerant flows or in the section closed acoustically blind.

However, it is also conceivable to provide the cross-sectional constrictions and cross-sectional expansions in both of these sections.

It is particularly advantageous if the cross-sectional constrictions and cross-sectional enlargements are arranged symmetrically to the inlet opening. Further features and advantages of the invention are the subject of the following description and the drawing of an exemplary embodiment.

The drawing shows:

1 shows a longitudinal section through a first embodiment of a refrigerant compressor according to the invention in the region of two cylinder chambers.

FIG. 2 shows a section along line 2-2 in FIG. 1;

Fig. 3 is a section along line 3-3 in Fig. 2;

4 shows an enlarged illustration of the section according to FIG. 1 in the region of the cylinder head;

5 shows a section similar to FIG. 4 through a region of the refrigerant compressor according to the invention having two other cylinder chambers and

6 shows a section similar to FIG. 4 through a second embodiment of a refrigerant compressor according to the invention.

A first exemplary embodiment of a refrigerant compressor according to the invention, shown in FIGS. 1 to 5, comprises a compressor housing, designated as a whole by 10, with a crankcase 11, in which two cylinder chambers 12a and 12b - left

are arranged in which pistons 14a, 14b can be moved in an oscillating manner, the pistons 14a, 14b interacting with connecting rods 16a, 16b with a crankshaft 18 which is arranged in the crankcase 11.

The crankshaft 18 is driven, for example, by an electric motor 20, the motor shaft 22 of which is arranged coaxially with the crankshaft 18 and carries a rotor 24 which is surrounded by a stator 26, which in turn is arranged stationary in the compressor housing 10.

The cylinder chambers 12a and 12b are closed at the head end by a valve plate 30 resting on the crankcase 11, which carries both intake valves and exhaust valves 32a and 32b.

On a side of the valve plate 30 opposite the crankcase 11 there is a cylinder head, designated as a whole by 40, which together with the valve plate 30 on the one hand includes a suction space 34, which lies above the inlet openings and into which refrigerant to be compressed flows in via a suction channel 36, and on the other hand a pressure chamber 38, which lies above the outlet valves 32a and 32b, so that compressed refrigerant from the cylinder chambers 12a and 12b enters the pressure chamber 38 via the outlet valves 32a and 32b.

The cylinder head 40 preferably comprises an outer wall area 42, which rests with a bearing surface 44 on a support surface 46 formed by the valve plate 30, and a cylinder head cover 48, which extends over the space enclosed by the outer wall area 42, comprising the suction space 34 and extends the pressure chamber 38 and runs approximately parallel to the valve plate 30 in order to close off the suction chamber 34 and the pressure chamber 38 on the side opposite the valve plate 30.

Furthermore, the cylinder head 40 also comprises a partition 50, which likewise extends from the valve plate 30 to the cylinder head cover 58 in order to separate the suction chamber 34 and the pressure chamber 38 from one another.

As shown in FIGS. 1 to 4, a damper channel, designated as a whole by 60, is formed in the cylinder head 40, specifically in the area of the partition 50 and near the cylinder head cover 48, the damper channel 60 running parallel to the cylinder head cover 48 with a central section 62 and with End sections 64, 66 merges in a curved manner in the area of the outer walls 42 and in the process has a first mouth opening 70 in the area of the first end section 64 and a second mouth opening 72 in the area of the second end section 66, which preferably lie in the plane of the bearing surface 74.

Furthermore, an inlet opening 74 is provided, which opens into the central region 62 of the damper channel 60.

As shown in FIGS. 1 and 4, in a first installation type of the cylinder head 40, the cylinder head 40 rests on the valve plate 30 such that a passage opening 76 provided in the valve plate 30 is aligned with the first opening 70 and also above an inlet opening 78 one designated as a whole with 80 and guided in the crankcase 11 outlet channel 80 opens. So that flows into the Compressed refrigerant entering the pressure chamber 38 initially enters the damper duct 60 via the inlet opening 74 and, however, only flows through this in the region of its section 82 extending from the inlet opening 74 to the first opening 70, while a section 84 lying between the inlet opening 74 and the second opening 72 does not is flowed through, since the second opening 72 is acoustically blind by an area 86 of the valve plate 30.

The section 84 thus serves as a so-called “blind section” of the damper channel 60.

Both the section 82 through which the compressed refrigerant flows and the section 84 of the damper channel 60 through which the flow of compressed air does not flow are effective for the damping effect of the damper channel 60, since the pulsations or pressure waves entering through the inlet opening 74 propagate in both directions along the sections 82 and 84. However, in the end region 66, which is acoustically blindly closed by the region 86 of the valve plate 30, there is a reflection at the closed end and the returning pressure waves then overlap again with the pressure waves entering further through the inlet opening 74. In addition, partial reflection also takes place at the first mouth opening 70 in the form of a reflection at the open end, so that the pressure waves, which are also returning, in turn overlap with the pressure waves entering through the inlet opening 74 and, overall, an advantageous damping effect of the damper channel 60 occurs. The reflection in the area of the mouth opening 70 is caused by a cross-sectional jump at the transition from the mouth opening 70 into the outlet channel 80, this cross-sectional jump being at least a factor 3 with regard to the cross-section effective for the outflowing compressed refrigerant.

Furthermore, a cross-sectional jump by at least a factor of 3, more preferably a factor of 5 or greater, is preferably also provided in the area of the inlet opening 74.

Another particular advantage of the damper duct 60, the length of which is relevant for the damping effect, is composed of the length of the sections 82 and 84 is that only the section 82 is flowed through by the escaping compressed refrigerant and the pressure loss resulting therefrom is therefore less than in FIG the case in which the entire damper channel 60 is flowed through by the compressed refrigerant.

The damping effect of the damper channel 60 is further improved by the fact that the inlet opening 74 is close to the cylinder head cover 48 and is preferably formed by a channel section 88, the longitudinal axis 90 of which is not directly facing the exhaust valves 32a and 32b, so that the pulsation or. Pressure wave first undergoes a deflection on the inside 92 of the cylinder head cover before it can enter the damper channel 60. In addition, an advantageous effect of the damper channel 60 can also be achieved in that the inlet opening 74 is positioned such that it can be arranged at approximately equal distances from the two outlet valves 32a and 32b.

The solution according to the invention, as shown in Fig. 5, has the further advantage that the same cylinder head 40 according to the invention can also be used for a crankcase 11 ', in which the exhaust port 80' is arranged so that the compressed refrigerant through the second Mouth opening 72 can enter this and consequently also the valve plate 30 'has a passage 76', while on the other hand the valve plate 30 'has a region 86' which closes the first opening 70 of the damper channel 60. The damper channel 60 acts in the same way, but in this case the section 84 is flowed through by the compressed refrigerant, while the section 82 represents the so-called "blind section" of the damper channel 60.

Such a cylinder head 40 can preferably be used to produce a four-cylinder refrigerant compressor, in which, in the case of two cylinder chambers 12a and 12b arranged on one side of the compressor housing 10, the corresponding crankcase 11 has the shape shown in FIGS. 1 and 4 and refrigerant compressed into the outlet duct 0 via the flows first inlet opening 70, while on the other side of the compressor housing 10, the corresponding crankcase 11 'is provided, in which the outlet channel 80' is arranged such that compressed refrigerant flows into the latter through the second opening 72. Thus, the cylinder head according to the invention can be used as the same part in different crankcases 11, 11 'with differently located outlet channels 80 and 80'.

In a second exemplary embodiment, shown in FIG. 6, those parts which are identical to those of the first exemplary embodiment are provided with the same reference numerals, so that with regard to the description thereof, reference can be made in full to the explanations regarding the first exemplary embodiment.

In contrast to the first exemplary embodiment, in which the damper channel 60 has a constant cross section over its entire length, the second exemplary embodiment provides that screens 100 'are inserted in the damper channel 60', which allow the cross section of the damper channel 60 'to vary, so that cross-sectionally narrowed sections 102 of the damper duct 60 'and section-widened sections 104 of the damper duct 60' follow one another, and the damping effect can thus be increased even further.

In particular, the cross-sectionally narrowed sections 102 and the cross-sectionally enlarged sections 104 are arranged both in the section 82 through which refrigerant flows and in the section 84 that is sealed off acoustically, preferably symmetrically to the inlet opening 74.

Otherwise, the second embodiment is designed in the same way as the first embodiment, so that identical parts are provided with identical reference numerals and thus reference can be made in full to the description thereof in connection with the first exemplary embodiment.

Claims

PATENT CLAIMS

1. refrigerant compressor, comprising a compressor housing (10), at least one cylinder chamber (12) arranged in the compressor housing (10), a piston (14) oscillating in the cylinder chamber (12), a suction chamber (34) upstream of the cylinder chamber (12) , from which refrigerant enters the cylinder chamber (12), a pressure chamber (38) downstream of the cylinder chamber (12) into which compressed refrigerant enters in the cylinder chamber (12), a between a first end (64) and a second end ( 66) extending damper channel (60), via which compressed refrigerant flows from the pressure space (38) into the outlet channel (80), characterized in that the damper channel (60) is between the first end (64) and the second end (66) Has inlet opening (74).

2. Refrigerant compressor according to claim 1, characterized in that the outlet opening (70, 72) is in the region of one of the ends (64, 66).

3. Refrigerant compressor according to claim 1 or 2, characterized in that the damper channel (60) in addition to the inlet opening (74) has two openings (70, 72), and that at least one of the openings (70, 72) forms the outlet opening.

4. A refrigerant compressor according to claim 3, characterized in that the two orifices (70, 72) are arranged in the region of opposite ends (64, 66).

5. A refrigerant compressor according to the preamble of claim 1 or one of the preceding claims, characterized in that the damper channel (60) extending between the two ends (64, 66) extends a section (82) through which the compressed refrigerant flows and an acoustically blind closure Section (84).

6. A refrigerant compressor according to claim 5, characterized in that the section through which the refrigerant flows (82) and the acoustically blind section (84) of the damper channel (60) extend away from the inlet opening (74).

7. A refrigerant compressor according to claim 5 or 6, characterized in that the section through which the refrigerant flows (82) and the acoustically blind section (84) extend in opposite directions from the inlet opening (74).

8. Refrigerant compressor according to one of the preceding claims, characterized in that the inlet opening (74) in the region of a central portion (62) of the damper channel (60).

9. A refrigerant compressor according to one of the preceding claims, characterized in that the damper channel (60) is arranged in a part (40) mountable on the compressor housing (10) and that the part (40) on the compressor housing (10) is mountable so that either the mouth opening (70) arranged at the first end (64) or the mouth opening (72) arranged at the second end (66) serves as an outlet opening and leads into the intended outlet channel (80, 80 ').

10. A refrigerant compressor according to claim 9, characterized in that the outlet opening (72, 70) which does not open into the outlet channel (80, 80 ') is acoustically blind.

11. A refrigerant compressor according to claim 10, characterized in that the acoustically blind closed opening (72, 70) is closed by a region (86, 86 ') of the part (30) which is the part (40) mountable on the compressor housing (10). wearing.

12. Refrigerant compressor according to one of the preceding claims, characterized in that the damper channel (60) extends in the cylinder head (40).

13. A refrigerant compressor according to claim 12, characterized in that the damper channel (60) is formed in the cylinder head (40).

14. Refrigerant compressor according to one of the preceding claims, characterized in that the damper channel (60) with a section (62) in an approximately parallel to a cylinder head cover (48) of the cylinder head (40) lying surface.

15. A refrigerant compressor according to claim 14, characterized in that the damper channel (60) with an essential portion (62) extends in the direction of a crankshaft (18).

16. A refrigerant compressor according to one of the preceding claims, characterized in that the damper channel (60) runs on a side of the pressure chamber (38) facing away from the cylinder chambers (12).

17. A refrigerant compressor according to claim 16, characterized in that the damper channel (60) in the direction of a crankcase (11) has end regions (64, 66).

18. A refrigerant compressor according to claim 17, characterized in that the orifices (70, 72) face the crankcase (11).

19. A refrigerant compressor according to claim 17 or 18, characterized in that the orifices (70, 72) of the damper channel (60) lie in a bearing surface (44) of the cylinder head (40).

0. Refrigerant compressor according to one of the previous ones

Claims, characterized in that the damper channel (60 ') has cross-sectional constrictions (102) and cross-sectional widenings (104).