EP1031727B1 - Air cooling system for a piston compressor - Google Patents

Abstract

The compressor has one or more cylinders (11, 12) and a crank shaft in a crank housing (15). The crankshaft is set vertical and underneath the cylinder a drive assembly (13), such as an electric motor, is coupled to the crankshaft. A ventilator (20) coupled to the drive assembly or crankshaft produces an air current which moves upwards along the drive assembly and along the cylinder. Compressed air flowing out of the or each cylinder is guided in pipes (34, 35) exposed to the cooling air current of the ventilator.

Description

The invention relates to a compressor with one or more cylinders in horizontal arrangement and with a crankshaft in a crankcase, wherein the compressor is arranged in a housing such that the crankshaft is vertically directed, that below the at least one cylinder coupled to the crankshaft drive unit is arranged and that a coupled to the drive unit or the crankshaft fan is provided.

From US 4,492,533 (Fig. 1), a compressor with a horizontal cylinder, vertical crankshaft, overhead fan and bottom drive motor is known. The air sucked into the surrounding housing from the fan flows downwards and exits from the housing in a lower area.

From GB 2 096 711 A (FIG. 6) a mobile compressor with two horizontal cylinders, upright crankshaft, fan arranged at the top and centrally arranged drive motor is known. The cooling air can flow both upwards and downwards depending on the drive of the fan. A particular disadvantage here is that, when the cooling air flows upwards, the air heated on the hot cylinders also acts on the drive motor.

From US 1 791 672 a compressor for the production of compressed air with two cylinders in a boxer arrangement is known. A common crankshaft mounted in a crankcase is driven by an electric motor. Electric motor and cylinder are in the same horizontal plane. The electric motor is mounted on its base on a foundation or bolted to it. The space requirement of the arrangement is relatively large. Object of the present invention is to provide a compressor as compact as possible.

The compressor according to the invention is characterized in that the crankshaft is directed vertically, that beneath the at least one cylinder a drive unit coupled to the crankshaft is arranged, that a fan coupled to the drive unit or the crankshaft is provided, and that the fan generates an airflow, which leads upwards on the drive unit and on the at least one cylinder.

In contrast to the prior art described above, the drive unit, preferably an electric motor, is arranged below the cylinders. This results in a significantly reduced space requirement. Also, the ventilation and cooling of both units can be done by a common air flow.

The vertical arrangement according to the invention - cylinder and drive unit one above the other - preferably has two cylinders in a boxer arrangement. But also possible versions with only one cylinder or with multiple cylinders in a different arrangement, such as in star or V arrangement. In all cases, the cylinders are provided transversely to the vertical crankshaft or drive shaft.

Advantageously, the drive unit is coupled to the crankshaft in the sense of a direct drive. But also possible is an indirect drive via a gearbox.

Below the cylinder, and in particular below the drive unit, a fan for generating an air flow is arranged. The fan is preferably designed as a radial fan, wherein the air flowing axially in a region of the fan facing away from the cylinders flows out in the radial direction and sweeps up the sides of the drive unit and / or on the cylinders. An upward flow of air for the cooling air and intake air is generated. Drive unit and Cylinders are provided with cooling fins. The upward flowing air sweeps past it and causes effective cooling. Due to the compact design of modern electric motors, the cylinders are laterally over and are exactly in the cooling air flow.

In the area of the entry of the air into the fan, a (first) suction filter is provided, preferably a filter mat. This is located near an inlet opening of the fan upstream inlet housing.

The cylinders are assigned a (second) air filter, in particular an air filter for several cylinders in common. The air filter is provided above the cylinder, in particular in the middle. Air inlet openings of the air filter are in the range of the above-mentioned upward-flowing air.

The air filter has an intake regulator, so that in the short term the delivery rate for all connected cylinders interrupted and thus the operation of the compressor can be adapted to a lower compressed air demand.

By means of a suitable intake air guide (the air to be compressed), the supply of warm air into the air filter can be avoided. Advantageously, there is an intake air duct from an intake opening below the cylinder to the air filter arranged above the cylinder. The intake air duct is a pipe with a corresponding cross section. The suction opening has a sufficient distance from heat-radiating surfaces, in particular cooling ribs. The actual distance depends on the concrete temperature and flow conditions.

The upward air flow is advantageously guided along by Luftleitorgane the cylinders and the crankcase and / or on the drive unit. As a result, a faster heat dissipation can be achieved.

Vibration technology, the Luftleitorgane are decoupled from the cylinders.

The compressor unit - cylinder, crankcase and drive unit - is mounted in a housing. The Luftleitorgane are assigned to the housing, while the compressor unit is mounted oscillating in the housing.

The air to be compressed is supplied to the cylinders on their upper sides and taken from the undersides as compressed air. Corresponding compressed air lines run in a plane below the cylinder and lie in the upward air flow.

The cylinders are interconnected by a common compressed air line. From one of the cylinders, this compressed air line continues and is guided around the crankcase in the same horizontal plane, in particular by 180 ° or more. In this case, the circulating compressed air line has a sufficient distance from the crankcase, so that the resulting heat of the lines is dissipated by the coolest possible rising air.

The arranged near the cylinders air filter advantageously has thermally insulated walls, in particular a insulating floor plate. Heating of the incoming air through the air filter housing is thereby avoided.

Drive unit and cylinder form a vibration control unit. The resonance frequency is correspondingly low. This is additionally reduced by further measures. So the unit is stored relatively low. For this purpose, support arms are provided whose free Tragarmenden are mounted on the housing side at bearing points at a height below a transition between the cylinders and the drive unit. On the side of the unit, the support arms engage approximately between the crankcase and the drive unit. The free arm ends rest on damping elements. These are in the amount of the center of gravity the oscillatory unit disposed on respective support beams or struts on the housing.

Due to the support arms, the unit is mounted in a star-shaped housing. The crankcase is at the center of the bearing points.

Finally, the cylinders are assigned additional weights, advantageously - based on the rotation of the crankshaft - radially outside the cylinder. With the help of additional weights, the mass moment of inertia can be increased by the center of gravity of the unit and thus counteracted in particular the formation of torsional vibrations.

Further features of the invention will become apparent from the claims.

Fig. 1

Eine perspektivische Darstellung eines Kompressoraggregats mit Zylindern und Antriebsmotor,

Fig. 2

eine teilweise geschnittene Seitenansicht eines Kompressors, mit Gehäuse,

Fig. 3

eine gegenüber der Fig. 2 um 90° versetzte Seitenansicht,

Fig. 4

eine perspektivische Darstellung eines Traggestells zur Aufnahme des Kompressoraggregats.

Fig. 5

eine vergrößerte Darstellung entsprechend Fig. 3 mit einem dort nicht gezeigten Detail.

Advantageous embodiments of the invention are explained below with reference to drawings. Show it:

Fig. 1

A perspective view of a compressor unit with cylinders and drive motor,

Fig. 2

a partially sectioned side view of a compressor, with housing,

Fig. 3

a comparison with FIG. 2 offset by 90 ° side view,

Fig. 4

a perspective view of a support frame for receiving the compressor unit.

Fig. 5

an enlarged view corresponding to FIG. 3 with a detail not shown there.

A piston compressor 10 with two cylinders 11, 12 in a boxer arrangement is encapsulated together with an electric drive motor 13 in a housing 14, see Figs. 2 and 3. The motor 13 is connected below a crankcase 15 with this. The drive shaft, not shown, and the crankshaft, also not shown, of the compressor are directly coupled and thus directed vertically. The crankcase 15 is also referred to as a cylinder console and accommodates an oil-free piston assembly having two pistons (also not shown).

The drive motor 13 is suspended. For this purpose, in the region of the transition between the engine 13 and the crankcase 15, radial (star-shaped) support arms 16 engage. Free ends 17 of the support arms rest on damping elements 18. These may have a rubber pad or the like and are fixedly connected to parts of the housing. In this way, the unit of cylinders 11, 12 and motor 13 is capable of oscillating relative to the housing 14. The free ends 17 are located approximately halfway up the drive motor 13. This results in a relatively low resonance frequency.

The resonance frequency is also reduced by additional weights 19. Each weight is assigned to a cylinder and sits in front of the front side. As a result, the additional weights 19 have the greatest possible distance from the center of gravity and increase the mass moment of inertia about the common center of gravity. The connection between the cylinders 11, 12 and the additional weights 19 may be provided, for example, by extended cylinder studs or bolts arranged parallel thereto.

At the bottom of the drive motor 13, a radial fan 20 connects, which rotates with the drive shaft, not shown. The air supply for the radial fan 20 is carried out from below axially via a nozzle 21. This is assigned to the housing 14, while the radial fan 20 is connected to the drive motor 13. Accordingly, nozzle 21 and radial fan 20 are vibrationally separated from each other.

The radially exiting from the radial fan 20 air is guided upward by a arranged in the housing spoiler device, in particular lower air baffles 22 and cools the drive motor 13, the cylinder 11, 12, the crankcase 15 and other heat-stressed parts. The heated air finally exits the housing 14 in an upper area, see air outlet 23 in FIGS. 2 and 3.

A portion of the upwardly directed air is supplied as an intake air to an air filter 24. This is designed as a flat rectangular housing and arranged on top of the crankcase 15. Fig. 1 shows an exploded view of the air filter 24. Visible are a bottom plate 25, a frame 26 and an upper cover 27th

The air flows into the air filter via a downwardly directed intake pipe 28 on the bottom plate 25, see in particular Fig. 5. The intake pipe 28 extends over more than 2/3 of the height of the crankcase 15. Thus, the heated air at the crankcase does not get into the Air filter 24.

The bottom plate 25 and optionally other parts of the air filter 24 are designed to be heat-insulating, so that even over a heat conduction no excessive heating of the intake air can take place.

The air filter 24 is provided with a controller 29 common to both cylinders 11, 12, see FIG. 5. In FIG. 1, only one recess in the frame 26 for the controller 29 can be seen. With the controller 29 a very short-term control of the compressed air delivery is possible. The more or less strong release of the intake air on the way to the cylinders 11, 12 is regulated. The intake air is supplied via respective intake lines 31, 32 from the air filter 24 to the two cylinders 11, 12, see FIG. 2. The air filter 24 is facing this purpose corresponding connection piece 33.

The generated compressed air is guided in a special way in the housing 14. Both cylinders are interconnected by a compressed air line 34 extending below the same in the horizontal plane, see Fig. 1. The compressed air line 34 begins at the cylinder 11 and continues beyond the cylinder 12 (more precisely below it) and is once passed around the crankcase , always in the same horizontal plane. In Fig. 1 of the cylinder 12 continued from part of the compressed air line is hidden and visible only with the parallel to the compressed air line 34 extending part (compressed air line 35). Its tail 36 is located approximately below the cylinder 12. The outlet of the compressed air from the housing is not shown. In any case, the compressed air after passing out of the cylinder 12 is guided by about 360 ° around the crankcase in a horizontal plane and thus lying in the upward cooling air flow. If the compressed air line 34 connecting the cylinders 11, 12 is added, the result is even 540 °. Due to the distance of the compressed air lines 34, 35 to the crankcase and the motor 13 is carried by the latter no heating of the lines 34, 35th

The housing 14 with cover plate 37, large side walls 38, 39 and narrow side walls 40, 41 encapsulates the compressor 10 against sound emissions and dust. An open bottom is covered by a large filter mat 42 and thus serves as an air inlet. The filter mat 42 is held in lateral guide rails. In this way, a dust accumulation inside the housing is avoided. Instead of the filter mat 42, other air filters can be used.

The outlet of the cooling air takes place in the region of the narrow side wall 40. For this purpose, this near the cover plate 37 has an opening 43 which extends over the entire width of the side wall 40. In the housing 14, a horizontal wall 44 is arranged as the lower boundary of the opening 43 and the air outlet 23, which, starting from the side wall 40 over approximately ¾ of the width of the side wall 39 extends and thus forms an exhaust duct 45 which has a downwardly directed passage 46 near the side wall 41.

On the large side walls 38, 99 Luftleitorgane 47, 48, in particular air baffles are arranged. These extend across the width of the large side walls 38, 39 and are directed obliquely up close to the cylinders 11, 12 and above the pressurized air ducts 34, 35. Thereby, the upward flowing cooling air is closely guided to the crankcase 15 and the flow velocity in this region is increased. This causes efficient cooling. The intake pipe 28 extends straight in the narrowest region between Luftleitorgan 47 and crankcase 15th

The nozzle 21 is inserted into an intermediate bottom 49. This is parallel to the underside and thus forms a suction chamber 50 for the nozzle 21. Preferably, insulating material is applied to the intermediate bottom. This is hatched in Fig. 2 and not shown in detail otherwise.

The housing 14 is constructed as a frame construction, as shown in Fig. 4. Outer upright struts 51 are on transverse struts 52 of a sub-frame 53. Above the sub-frame 53 and at a distance from this, the intermediate bottom 49 is retracted. On a narrow side wall 41, a control cabinet 54 is disposed above the intermediate floor 59.

Approximately half the height of the struts 51, a middle frame 55 is connected to corresponding transverse struts 56 with the upright struts 51. On the cross struts 56, the damping elements 18 are held. Accordingly, the compressor unit is mounted on the center frame 55 swingable.

Not shown in Fig. 4, the cover plate 37 and the wall 44 parallel thereto.

The described compressor 10 can be varied in many ways. Thus, other cylinder arrangements may be provided, for example 2x2 cylinders, each in a boxer arrangement, with an offset of 90 ° to one another, or a multi-stage arrangement in which the compressed air emerging from the one cylinder is sucked by the next cylinder and further compressed. Also, oil lubricated piston-cylinder assemblies can be installed. The crankcase 15 may then be fully enclosed. In the present embodiment, the crankcase at each of the free sides (at the upper edge) between the cylinders V-shaped passages 57, in Fig. 1, the rear passage is hidden. As a result, cooling air enters the crankcase. This is supported by the design and arrangement of the Luftleitorgane 47th

Finally, reference is made to the guidance of the air within the housing 14. To illustrate the air flows are shown in FIGS. 2, 3 and 5 arrows without numbers. The housing or the housing walls form an outer guide for the cooling air flow.

List of reference numbers :

10

compressor

11

cylinder

12

cylinder

13

engine

14

casing

15

crankcase

16

carrying arms

17

free ends

18

damping elements

19

additional weights

20

radial fans

21

jet

22

lower baffles

23

air outlet

24

air filter

25

baseplate

26

frame

27

top cover

28

intake

29

regulator

30

recess

31

suction

32

suction

33

connecting branch

34

Compressed air line

35

Compressed air line

36

tail

37

cover plate

38

large side wall

39

big sidewall

40

narrow side wall

41

narrow side wall

42

filter mat

43

opening

44

wall

45

exhaust duct

46

passage

47

Luftleitorgane

48

Luftleitorgane

49

false floor

50

chamber

51

pursuit

52

crossbars

53

subframe

54

switch cabinet

55

center frame

56

crossbars

57

neckline

Claims (13)

1. Compressor with one or more cylinders (11, 12) arranged horizontally and with a crankshaft in a crankcase (15), the compressor being arranged in a housing (14) such that the crankshaft is aligned vertically, such that a drive assembly (13) coupled to the crankshaft is arranged underneath the at least one cylinder (11, 12), and such that a fan (20) coupled to the drive assembly (13) or to the crankshaft is provided, characterized in that the fan (20) is arranged underneath the at least one cylinder (11, 12), in particular underneath the drive assembly (13) and thus produces an air flow which is guided upwards along the drive assembly (13) and along the at least one cylinder (11, 12).
2. Compressor according to Claim 1, characterized in that the fan (20) is designed as a radial fan, the outflowing air flowing upwards laterally along the drive assembly (13) and along the at least one cylinder (11, 12).
3. Compressor according to Claim 1 or 2, characterized in that the intake air for the cylinders (11, 12) is drawn in in a region underneath the cylinders (11, 12) or at a distance from the latter and is fed to one or more air filters (24).
4. Compressor according to Claim 1, characterized in that the intake air is guided from an intake opening close to a region underneath the cylinders (11, 12) to an air filter (24) arranged above the cylinders.
5. Compressor according to Claim 1, characterized in that an upward flow of cooling air is guided along the cylinders (11, 12) and along the crankcase (15) by air guide members (47, 48).
6. Compressor according to Claim 5, characterized in that the air guide members (47, 48) are mounted on housing walls (38, 39) which are decoupled from the cylinders (11, 12) in terms of vibration.
7. Compressor according to Claim 1, characterized in that the compressed air emerging from the cylinder or cylinders (11, 12) is carried in lines (34, 35) which are exposed to a flow of air, in particular a flow of cooling air from a fan (20).
8. Compressor according to Claim 7, characterized in that the lines (34, 35) are arranged in a plane transverse to the flow of air.
9. Compressor according to Claim 7 or 8, characterized in that, after emerging from the cylinders (11, 12), the lines (34, 35) are passed around the crankcase (15), below the cylinders, in particular at least once around the crankcase.
10. Compressor according to Claim 7, characterized in that a plurality of cylinders (11, 12) are connected to one another on the compressed-air side by a common connecting compressed-air line (34).
11. Compressor according to Claim 10, characterized in that a compressed-air outlet line (35) common to a plurality of cylinders is connected to the connecting compressed-air line (34).
12. Compressor according to Claim 1, characterized in that arranged underneath the cylinders (11, 12) is a drive motor (13), which is coupled to the cylinders (11, 12) to form a unit, in that the unit is mounted in a star shape with projecting supporting arms (16), and in that, to lower a resonant frequency, free ends (17) of the supporting arms are mounted at mounting points at a level below a transition between the cylinders (11, 12) and the drive motor (13).
13. Compressor according to Claim 1, characterized in that the cylinders (11, 12) are assigned additional weights which, with respect to the rotation of the crankshaft, are arranged radially to the outside of the cylinders (11, 12).

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