EP0837241B1 - Axial piston pump with adjustable control plate - Google Patents

Description

The invention relates to an axial piston machine according to the preamble of claim 1.

A generic axial piston machine is e.g. known from EP 0320 822 B1. At the axial piston machine disclosed in this publication is a Swashplate type axial piston machine, one around a cylinder drum axis comprises rotatably mounted cylinder drum in which cylinder bores are formed, in which pistons are slidably guided. Around the cylinder bores around Cylinder drum axis rotating cylinder drum with one in one Connection plate formed low-pressure connection opening and one in the To connect the connection plate also formed high-pressure connection opening is one Control disc arranged between the cylinder drum and the connecting plate kidney-shaped control openings provided.

In the axial piston machine known from EP 0320 822 B1, it is provided that kidney-shaped control openings of the control disk in the direction of rotation of the cylinder drum to move slightly. This is commonly known as and twist the control disc is referred to below in this way. The twisting of the control disc serves a reduction in noise level and a decrease in pressure pulsation. Since the Twisting the control disc depends on the direction of rotation of the cylinder drum, it is when changing the direction of rotation required to turn the control disc so that a The kidney-shaped control openings are twisted in the opposite direction of rotation becomes. For this purpose, in the known axial piston machine, the connection plate has to be dismantled, so that the control disc is accessible. Furthermore, one is not accessible from the outside To loosen the pin connection that fixes the control disc with respect to the connection plate and fasten again after turning the control disc. After that is the Reassemble the connection plate. A conversion of the known Axial piston machine in order to prepare them for the reverse direction of rotation is required therefore a relatively large assembly effort. This is a hindrance since the mission-specific The direction of rotation of the axial piston machine is usually not yet determined when it is installed and the need to change the direction of rotation is therefore relatively common in practice results.

On the other hand, it is known from U.S. Patent 3,190,232 and U.S. Patent 2,546,583, one Realizable changeable twist of the control disc in that the control disc has an eccentric, on which a hydraulic actuating device acts. However, this solution is relatively complex and costly and has therefore in the Practice not enforced.

The invention has for its object to provide an axial piston machine which is a change of direction without complex assembly and conversion work in is simple to carry out.

The object is in connection with the characterizing features of claim 1 solved with the generic features.

The invention is based on the finding that by one of the control disc opposite side of the connecting plate accessible pin connection the control disc fixed in relation to the connection plate in a simple manner and thus the angle of rotation can be flexibly set between the control disc and the connection plate.

Claims 2 to 11 relate to advantageous developments of the invention.

The control disc is fixed in at least two different angular positions with regard to the connection plate can advantageously according to claim 2 achieved that the connecting plate and the control disk at least two Recesses, e.g. in the form of two holes, and the Angle of rotation of the recesses of the connecting plate not with the Angle of rotation of the recesses of the control disc coincides.

According to claim 3, the recesses can preferably be circular Bores or peripherally arranged part-circular recesses, the predetermined possible twists of the control disc with respect to the connection plate each have a concentric alignment of a specific bore or recess Connection plate with a specific hole or cutout in the control disc corresponds, which can be fixed according to claim 4 by means of the fixing pin in that the locating pin both in the hole or recess in the control disc and in the Bore or recess of the connection plate engages. The recess in the Control plate can in particular as a leading through the connection plate Bore be formed, in which the fixing pin according to claim 5 of the Control disc facing away is insertable. This ensures that the Fixing pin is accessible from outside the axial piston machine and changing the plug Fixing pin when changing the direction of rotation of the axial piston machine not the Disassembly of the connection plate required. This will make the conversion work at one change of direction of rotation on the axial piston machine to a minimum reduced. It is only necessary to reposition the fixing pin.

The recesses in the control disc can according to claim 6 and 7 as Bore, in particular blind bore, or as a preferably part-circular recess be formed in the peripheral region of the control disk.

According to claim 8, the fixing pin can preferably have a conical section have to when inserting the locating pin into the bore or into the recess the control disc, the concentric alignment between the bore or recess the connecting plate and the bore or the recess of the control disc in simple Way to bring about. The change in the twisting of the control disc and the fixation is therefore in a single step, namely the insertion or insertion of the Fixing pin performed in the corresponding hole in the connection plate. Furthermore, the fixing pin advantageously according to claim 9 a spiral or have an eccentric section in order to twist the fixing pin slightly Twisting the control disc relative to the connecting plate and thus bring about Allow fine adjustment.

Furthermore, by inserting a plurality of stepped fixing pins according to claim 10 achieved that the control disc in a neutral position on the connection plate is fixed, the control disc in this neutral position neither twisting in which still points in the other direction. This is the case for some use cases Axial piston machine advantageous.

Fig. 1

einen axialen Längsschnitt durch ein Ausführungsbeispiel einer erfindungsgemäßen Axialkolbenmaschine;

Fig. 2A

einen Schnitt durch die Anschlußplatte und die daran montierte Steuerscheibe entsprechend dem Ausführungsbeispiel nach Fig. 1,

Fig. 2B

eine Aufsicht auf die Anschlußplatte entsprechend Fig. 2A,

Fig. 2C

einen erfindungsgemäßen Fixierstift,

Fig. 2D

eine Sicht auf die Steuerscheibe und die Anschlußplatte entsprechend den Fig. 2A und 2B,

Fig. 3A

einen Schnitt durch die erfindungsgemäße Anschlußplatte und die daran montierte Steuerscheibe, wobei die Steuerscheibe in einer Neutralstellung fixiert ist;

Fig. 3B

eine Aufsicht auf die Anschlußplatte entsprechend Fig. 3A,

Fig. 3C

einen Fixierstift, um die Steuerscheibe an der Anschlußplatte in der Neutralstellung zu fixieren,

Fig. 3D

eine Sicht auf die Steuerscheibe entsprechend Fig. 3A und 3B, die an der Anschlußplatte in ihrer Neutralstellung fixiert ist;

Fig. 4A

eine erfindungsgemäße Steuerscheibe entsprechend einem weiteren Ausführungsbeispiel der Erfindung,

Fig. 4B

einen Schnitt durch die Anschlußplatte und die daran fixierte Steuerscheibe entsprechend dem Ausführungsbeispiel nach Fig. 4A,

Fig. 4C

die Steuerscheibe entsprechend Fig. 4A in einer geringfügig verdrehten Position,

Fig. 4D

eine Fig. 4B entsprechende Darstellung mit geringfügig verdrehter Steuerscheibe entsprechend Fig. 4C.

The invention is described in more detail below with reference to the drawing. The drawing shows:

Fig. 1

an axial longitudinal section through an embodiment of an axial piston machine according to the invention;

Figure 2A

2 shows a section through the connecting plate and the control disk mounted thereon in accordance with the exemplary embodiment according to FIG. 1,

Figure 2B

a plan view of the connection plate corresponding to Fig. 2A,

Figure 2C

a fixing pin according to the invention,

Figure 2D

a view of the control disc and the connecting plate according to FIGS. 2A and 2B,

Figure 3A

a section through the connecting plate according to the invention and the control disc mounted thereon, the control disc being fixed in a neutral position;

Figure 3B

a plan view of the connection plate corresponding to Fig. 3A,

Figure 3C

a fixing pin to fix the control disc on the connection plate in the neutral position,

Fig. 3D

3A and 3B, which is fixed to the connecting plate in its neutral position;

Figure 4A

a control disk according to the invention according to a further embodiment of the invention,

Figure 4B

4 shows a section through the connecting plate and the control disk fixed thereon in accordance with the exemplary embodiment according to FIG. 4A,

Figure 4C

4A in a slightly rotated position,

Figure 4D

a representation corresponding to FIG. 4B with a slightly rotated control disk corresponding to FIG. 4C.

Fig. 1 shows an embodiment of an axial piston machine, on which the Further development according to the invention is realized in an axial longitudinal section. The Axial piston machine 1 is designed in the exemplary embodiment in a sliding axis construction and comprises a drive shaft 2, which in a housing 3 by means of roller bearings 4 and 5th is rotatably mounted. A cylindrical drum 6 is in an angled housing part 3a a cylinder drum axis 7 rotatably arranged. The cylinder drum axis 7 is angled relative to the axis 8 of the drive shaft 2 by a predetermined angle. On the drive shaft 2 is at the end facing the cylinder drum 6 Formed drive flange 9. There are several cylinder bores in the cylinder drum 6 10 is provided, in which associated pistons 11 are each slidably guided. The Pistons 11, which taper conically in the direction of a spherical head 12, are supported with their ball head 12 on the drive flange 9 and lead due to Angular misalignment between the axis 8 of the drive shaft 2 and the cylinder drum axis 7 with each revolution of the cylinder drum 6 and the drive shaft 2 in the associated Cylinder bores 10 a lifting movement.

A bearing pin 13 is used to mount the cylinder drum 6, which Guide bore 14 of the cylinder drum 6 engages. The guide pin 13 has also a ball head 15, which is in a spherical bearing 16 of the Drive flange 9 supports.

The ball heads 12 of the pistons 11 are each supported in a spherical bearing 17 of the Drive flange 9 from. For lubrication and hydraulic relief of the spherical Bearing 16, each piston 11 has a lubrication bore 18, which has a throttle point 19 communicates with a pressure pocket 32. In the same way, the Guide pin 13 for lubrication and hydraulic relief of the spherical bearing 16 has a longitudinal bore 20 with connecting channels 21 and 22 in the drive shaft 2 is connected and is therefore connected to a lubrication circuit that can also serve the lubrication of the rolling bearings 4 and 5. In the housing 3 a leak oil drain 23 is also provided. The cylinder drum 6 is by means of a preferably designed as a plate spring compression spring 24 which in the guide bore 14th the cylinder drum 6 is inserted and against the ball head 15 supports the opposite end of the guide pin 13 against a control disk 25 biased. The control disc 25 is between the cylinder drum 6 and the Connection plate 26 arranged and fixed to the connection plate 26.

In the control disk 25, kidney-shaped are shown in FIGS. 2D and 3D Control openings 27 and 28 provided to the cylinder bores 10 over Connection channels 29 cyclically with each revolution of the rotating cylinder drum 6 a low-pressure connection opening 60 provided in the connection plate 26 and one high pressure connection opening 61 also provided in the connection plate 26 connect. The connection plate is e.g. via mounting screws 30 and 31 on the housing 3 releasably attached.

As already described in the introduction, it is to optimize the noise behavior and Reducing the pressure pulsation is common and known as such, the control disk 25 to twist slightly with respect to the connecting plate 26, i.e. a minor one Subject to angular misalignment. Because this twist is basically in the direction of rotation takes place, it is when the direction of rotation of the axial piston machine 1 changes necessary to adapt this twist to the changed direction of rotation. The twist around the angle α is e.g. seen from Fig. 2D. Because of the following too Descriptive training according to the invention, it is possible with a Change of direction of rotation the necessary change in the twist of the control disc 25th opposite the connecting plate 26 from the outside by repositioning a fixing pin 43 bring about, without the connecting plate 26 as in known axial piston machines Disassembled and customary to adapt the twist to the changed direction of rotation must then be reassembled. As a result, the assembly effort for one change of direction to be carried out is considerably reduced.

According to the embodiment shown in FIGS. 2A to 2D and 3A to 3D of the development according to the invention are two step-shaped in the connection plate 26 trained through holes 40 and 41 provided by the of the control disc 25 side facing away from the connecting plate 26 for inserting a fixing pin 43 are accessible. The through holes 40 and 41 are in the embodiment by means of two closure elements 42 and 44 closable, which in the through holes 40th and 41 e.g. are screwable to loosen or fall out of the fixing pin 43 prevent.

As can be seen from FIG. 2A, only one fixing pin 43 is in the through hole 40 inserted while there is no fixing pin in the through hole 41. On in this way, the control disk 25 is in a specific, predetermined angular position, the twisting of the control disk 25 in a certain direction of rotation Axial piston machine 1 corresponds, fixed. If the fixing pin 43 instead of in the Through hole 40 inserted into the other through hole 41, so the Control disc 25 fixed with an opposite twist on the connecting plate 26.

The fixing pin 43 has a guide section 45 which can be seen better from FIG. 2C, which forms a fit with a guide section 46 of the through hole 40. If the fixing pin 43 is inserted into the other through hole 41 forms the Guide section 45 with the guide section 48 of the through hole 41 a appropriate fit.

The control disc 25 is pivotally mounted in a retaining bolt 47 so that the Control disk 25 in a certain angle of rotation range around the cylinder drum axis 7 can be pivoted or rotated relative to the connecting plate 26. The Control disc also has two with the through holes 40 and 41 of the Connection plate 26 corresponding blind holes 49 and 50. How better from Fig. 2D can be seen that a top view of the one mounted on the connection plate 26 Control disc 25 shows, the blind holes 49 and 50 are double Twist angle 2α offset from each other. As also shown in Fig. 2D results, the guide portion 46 of the through hole 40 is due to the in the Through hole 40 inserted fixing pin 43 concentric with the blind hole 49 aligned so that the guide portion 46 and the blind bore 49 in Fig. 2D collapse. At the same time, however, the blind bore 50 is not concentric with that Guide portion 48 of the through hole 41 aligned, which is also in Fig. 2D is made clear.

When converting the axial piston machine 1 for a change of direction are first to remove the two closure elements 42 and 44, so that the in Through hole 40 of the connecting plate 26 inserted fixing pin 43 is accessible. The fixing pin 43 is then removed. For this purpose, the fixing pin 43 in his Holding section 41 a e.g. threaded blind bore 52 into which a tool can intervene or be screwed in, so that the fixing pin 43 from the Through hole 40 is pulled out. Then the fixing pin 43 in the other Through hole 41 of the connecting plate 26 inserted and pressed.

At the same time the necessary rotation of the control disk 25 by twice To effect twist angle 2α, the fixing pin 43 has on its the control disc 25 facing end a conical section 53. The conical section 53 is like this shaped that the diameter at the tip of the fixing pin 43 is so small that the conical section 53 into the clear width not covered by the guide section 48 the blind bore 50 penetrates. By pushing in the fixing pin and moving the Fixing pin in the direction of the control disc 25, the conical section 53 causes corresponding rotation of the control disk 25 until the guide section 48 is aligned concentrically with the blind bore 50 and the guide section 45 of the Fixing pin 43 both in the blind bore 50 and in the guide section 48 of the Through hole 41 engages and thus the concentric orientation of the Guide section 48 fixed with the blind bore 50. Below are the Closure elements 42 and 44 are reinserted in both through holes 40 and 41 or screwed in again.

The assembly effort for converting the axial piston machine 1 at one The direction of rotation to be carried out is due to the development according to the invention therefore reduced to a minimum.

Fig. 2B shows the connection plate corresponding to Fig. 2A in a plan view accordingly the viewing direction marked with arrow 54. Are recognizable from this Representation of the closure elements 42 and 44, the through holes 40 and 41st close. Furthermore, the low pressure connection opening 60 and the high-pressure connection opening 61 can be seen. It can be seen that the Through holes 40 and 41 for the fixing pin 43 outside the connection openings 60 and 61 are arranged so that sealing problems are avoided.

2D shows the control disk 25 mounted on the connecting plate 26 accordingly the viewing direction indicated by arrow 55 in FIG. 2A.

3A to 3D show a further development according to the invention with reference to the embodiment already described with reference to FIGS. 1 and 2A to 2D. Already elements described are identified by the same reference numerals, so that a description in this regard is unnecessary.

3A to 3D is in both Through holes 40 and 41 each inserted or inserted a fixing pin 43.

The fixing pins 43 that can be seen in detail in FIG. 3C, however, point towards the with reference to the fixing pin 43 described in FIG. 2C, a slight modification. The Guide section 45 is shortened in its axial length and instead of a conical Section 53 is a tapered section 62 is provided so that there is a step-shaped Formation of the fixing pin 43 results. The diameter of the tapered portion 62 is dimensioned half as large as the diameter of the guide section 45. By Inserting a fixing pin 43 both in the through hole 40 and in the through hole 41 becomes the control disk 25 in its symmetrical Neutral position fixed with twist angle α = o. This angular position of the Control disk 25 is advantageous in some applications of the axial piston machine 1, especially when the axial piston machine 1 is constantly changing the direction of rotation is subject.

3B shows a top view of the connection plate 26 in a manner corresponding to FIG. 2B corresponding to the viewing direction indicated by arrow 54 in FIG. 3A. Fig. 3D shows, in a manner corresponding to FIG. 2D, a plan view of the connection plate 26 mounted control disc 25 according to the arrow 55 in Fig. 3A marked viewing direction. 3D shows the position of the tapered sections 62 of the two locating pins 43 with respect to the blind bores 49 and 50. Doing so clearly that the tapered portions 62 of the fixing pins 43 each in a half-surface the cross-sectional area of the blind bores 49 and 50 are arranged and on the The lateral surface of the blind bores 50 and 49 each lie flush on one side. To this A way of fixing the control disk 25 is shown in FIG. 3D Neutral position achieved.

With the further development according to the invention it is therefore possible on the one hand that Axial piston machine 1 with very little assembly effort for an opposite Change direction of rotation. On the other hand, it is due to the further development according to the invention also possible to fix the control disc 25 in a neutral position, so that the Axial piston machine 1 can be operated in both directions of rotation. It should be emphasized that the connection plate 26 does not have to be dismantled during the conversion work.

4A to 4D show a modified embodiment of the invention. Already elements described are identified by the same reference numerals, so that a description in this regard is unnecessary.

One of the differences of the embodiment shown in FIGS. 4A to 4D compared to that described with reference to FIGS. 2A to 2D and 3A to 3C Embodiment consists in that on the control disc 25 no blind holes, but part-circular recesses 70 and 71 are provided. The one from Fig. 4B apparent, in a through hole 40 of the two through holes 40, 41 of Terminal plate 26 inserted fixing pin 43 partially penetrates into the recess 70. In its end area facing the control disk 25, the fixing pin 43 has a spiral section 72. The spiral inclined surface 73 is located on an edge 74 of the recess 70. By turning the fixing pin 43 e.g. by means of a tool engaging a groove 75 moves the contact point between the edge 74 of the recess 70 and the inclined surface 73 of the fixing pin 43 in the axial Direction. This has a slight twist of the control disk 25 around the Cylinder drum axis 7 result.

For clarification, the control disk 25 is slightly rotated in FIG. 3C Position shown again, that of the rotated position shown in Fig. 4D Fixing pin 43 corresponds. By turning the fixing pin 43 can therefore in one certain range, the angular position of the control disk 25 and thus the Twist angle α can be adjusted. This fine adjustment allows the Optimize twist angle α so that there is an optimized noise behavior and a minimized pressure pulsation results. In the other, which cannot be seen from FIG. 4B Through hole 41 of the connecting plate 46 can be in a corresponding manner trained fixing pin 43 may be used, the fixing pins 43 each in opposite directions are twisted to twist the control disk 25 and at the same time to fix it.

The invention is not limited to the illustrated embodiment. In particular is it is also possible to provide several bores or recesses in the control disk, to vary the twist angle α in steps for each direction of rotation.

Claims (11)

1. Axial piston machine (1) having a cylinder drum (6) which is mounted so as to be rotatable about a cylinder drum axis (7) and in which there are constructed cylinder bores (10) in which pistons (11) are displaceably guided,

   a connecting plate (26) in which a low-pressure connecting aperture (60) and a high-pressure connecting aperture (61) are constructed,

   a control disc (25) in which control apertures (27, 28) are constructed, for the purpose of connecting the cylinder bores (10) in the cylinder drum (6) rotating about the cylinder drum axis (7) to the low-pressure connecting aperture (60) and the high-pressure connecting aperture (61) in a cyclical manner, and

   a fixing arrangement, for the purpose of fixing an angle (α) of twist which the control disc (25) assumes in relation to the connecting plate (26),

   characterised in that
   the fixing arrangement comprises at least one fixing pin (43) which is accessible from the side of the connecting plate (26) facing away from the control disc (25), is located outside the connecting apertures (60, 61), fixes the control disc (25) in relation to the connecting plate (26) and thus sets the angle (α) of twist between the control disc (25) and the connecting plate (26).
2. Axial piston machine according to claim 1,
   characterised in that
   at least two clearances (40, 41; 49, 50, 70, 71) in each case are provided in the connecting plate (26) and the control disc (25), although the rotation-angle interval between the clearances (40, 41) in the connecting plate (26) does not correspond to the rotation-angle interval between the clearances (49, 50; 70, 71) in the control disc (25).
3. Axial piston machine according to claim 2,
   characterised in that
   the clearances (40, 41; 49, 50, 70, 71) are constructed as circular bores (40, 41; 49, 50) or partially circular recesses (70, 71), and a predetermined angle (α) of twist between the connecting plate (26) and the control disc (25) is set as a result of the concentric alignment of a certain bore (40, 41) or recess in the connecting plate (26) with a certain bore (49, 50) or recess (70, 71) in the control disc (25).
4. Axial piston machine according to claim 3,
   characterised in that
   the concentric alignment of a certain bore (40, 41) or recess in the connecting plate (26) with a certain bore (49, 50) or recess (70, 71) in the control disc (25) can be fixed by the fixing pin (43) which engages in the bores or recesses in the connecting plate (26) and control disc (25).
5. Axial piston machine according to one of claims 2 to 4,
   characterised in that
   the clearances (40, 41) in the connecting plate (26) are constructed as through-bores (40, 41) which lead through the said connecting plate (26) and in which the fixing pin (43) can be inserted from the side facing away from the control disc (25).
6. Axial piston machine according to one of claims 2 to 5,
   characterised in that
   the clearances in the control disc (25) are constructed as bores, in particular blind bores (49, 50), in which the fixing pin (43) engages.
7. Axial piston machine according to one of claims 2 to 5, characterised in that
   the clearances in the control disc (25) are constructed as peripherally disposed, partially circular recesses (70, 71) in which the fixing pin (43) engages.
8. Axial piston machine according to one of the preceding claims insofar as they are referred back to claim 3,
   characterised in that
   the fixing pin (43) has a conical section (53) for the purpose of bringing about concentric alignment between the bore (40) or recess in the connecting plate (26) and the bore (49) or recess (70) in the control disc (25) when the said fixing pin (43) is inserted in a bore (49) or recesses in the control disc (25).
9. Axial piston machine according to one of claims 1 to 8,
   characterised in that
   the fixing pin (43) has a spiral-shaped and/or eccentric section (72) for the purpose of bringing about, by twisting the said fixing pin (43), an adjustment of the angle (α) of twist which the control disc (25) assumes in relation to the connecting plate (26).
10. Axial piston machine according to one of the preceding claims insofar as they are referred back to claim 2,
    characterised in that
    the fixing pin (43) is of stepped construction and has a guide section (45) and a tapered section (62), so that the simultaneous introduction of a number of fixing pins (43) into a number of clearances in the connecting plate (26) and control disc (25) results in the fixing of the said control disc (25) at a neutral angle of twist (α = 0) in relation to the said connecting plate (26).
11. Axial piston machine according to claim 10,
    characterised in that
    the diameter of the tapered section (62) is dimensioned so as to be half as large as the diameter of the guide section (45).

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