EP2789862A1 - Oscillation excite for construction machines - Google Patents

Abstract

The invention relates to a swivel motor, in particular for a vibration exciter for construction machines, with a swivel motor housing which is rotatably mounted on a pivot motor shaft, wherein at least two pressure chambers are arranged to act on a hydraulic oil, via which the swivel motor is operable. The pivot motor shaft (51) is provided with an axial bore (511) into which a non-rotatably mounted lance (6), are guided by the axially at least two channels (64) for oil supply to the pivot motor (5) in spaced from each other on the outside on the lance (6) at least partially circumferentially introduced annular grooves (65) open, wherein in the pivot motor shaft (51) radial bores (512) for connecting the at least two annular grooves (65) of the lance (6) with the at least two pressure chambers (57) are introduced.

Description

The invention relates to a pivoting motor, in particular for a vibration generator for construction machines, in particular for vibrating rams, according to the preamble of patent claim 1.

In the construction industry, vibratory rams are used to bring in piles such as profiles in the ground or to pull them out of the ground. The soil is excited by vibrations with a frequency above the natural frequency of the soil and thus reaches a "pseudo-liquid state". By static load the pile can then be pressed into the ground. The vibration is generated by pairwise counter-rotating imbalances.

The vibration exciters of such vibration rams are linear-acting vibration exciters whose centrifugal force is generated by rotating imbalances. An essential feature of these vibration exciters is the static moment. This is a size that describes the installed imbalance. When trained as Verstellvibratoren vibration exciters, the effective size of the imbalance is adjustable. To limit the rolling bearing load, the static torque is adjusted by adjusting the effective unbalance of each shaft. As a rule, an average imbalance is rotated against two outer imbalances in order to adjust the resulting imbalance in this way. Since the internal imbalances of all shafts are interconnected via gears and the external imbalances of all shafts via gears or the shafts themselves, the relative angles between external and internal imbalances are the same on all shafts. Such a trained vibration exciter is for example in the DE 20 2007 005 283 U1 disclosed. Here, the adjustment of the imbalance groups via a pivot motor, which is designed as a rotating gear shaft, wherein the adjustment is made via a druckölbeaufschlagten rotary piston, which is rotatable relative to this within the swing motor housing.

Essential for the operation of such swivel motors is the transfer of oil to the rotating swing motor. Usually, rotary feedthroughs are used for this purpose in the prior art, which consist of a fixed housing, which is flanged to the housing of the vibration exciter and a rotor which is rotatably mounted in this housing and is driven by the rotating pivot motor. Bearings always have a bearing clearance, whereby all components mounted in a swinging housing rotate with a certain eccentricity. While this is relatively large in self-mounted rotary motors, very tight games are required in rotary feedthroughs for sealing reasons. A directly rigid connection between the rotor of the rotary feedthrough and the swivel motor shaft is not possible, since the heavy swing motor would damage the sensitive bearings of the rotary feedthrough. Currently, attempts are being made to solve this problem by the use of intermediate flexible tubes, which are sealed on the one hand in frontal bores in the swing motor shaft and on the other hand also sealed to the rotor of the rotary feedthrough. As a result, a mutually movable connection is achieved.

A disadvantage of the above solution is that it is very expensive to produce and also takes up much space, since the rotary feedthrough builds up to the outside and is in exposed position in front of the housing. In addition, the tubes are sealed with O-rings, which are subject to high wear due to the dynamic load, which is why they must be changed frequently.

The invention aims to remedy this situation. The invention is based on the object to provide a pivot motor in particular for a vibration exciter for construction equipment, whose manufacturing and maintenance costs are reduced in particular in relation to the oil supply and also claimed a smaller space. According to the invention, this object is achieved by features of the characterizing part of patent claim 1.

With the invention, a pivot motor is created in particular for a vibration exciter for construction machinery, whose manufacturing and maintenance is reduced in particular with respect to the oil supply and also claimed a smaller space. By providing an axial bore in the pivot motor shaft into which projects a non-rotatably mounted lance through which are guided axially at least two channels, which open at least partially circumferentially introduced grooves in adjacent outside of the lance outside of the lance, wherein in the swing motor shaft Radial holes for connecting the at least two annular grooves of the lance are introduced with the at least two pressure chambers, a reliable and at the same "elastic" oil supply of the swing motor is achieved. The fixed arranged lance compensates for the dancing movement of the pivot bearing shaft in the functionally bearing a game bearing bearings. This is done on the one hand by the long shaft of the lance, which is preferably designed to be elastic and is advantageously designed by attachment to the housing of the vibration exciter so that it can accommodate slight inclinations. In this case, the lance is preferably rotatably mounted end with play in a fixed to the housing of the vibration exciter flange. The elasticity of the lance can be increased by having a reduced diameter in the region of the shank.

The oil is supplied to the chambers from the outside, wherein the oil is first passed through the at least two axial channels of the lance into the region of the shaft, which is enclosed by the pivot motor housing. The two channels have different lengths and open into a respective groove which encloses the lance at the level of the mouths of the holes. On the shaft side opens into this groove a radial bore through which a chamber of the swing motor is supplied with oil.

In a further development of the invention, the lance and the axial bore of the pivot motor shaft in the region of the annular grooves of the lance or preferably in the region of the pivot motor shaft, which is enclosed by the pivot motor housing, designed as a sliding bearing with very close game. The narrow gap between the lateral surface of the lance and the axial bore of the pivot motor shaft serves to seal the at least two grooves against each other and with respect to the vibration exciter interior. The surface of the lance is in the range of this Plain bearing preferably provided with a lubricious coating, preferably a plastic coating, which is preferably applied as a lacquer.

In an embodiment of the invention, no sliding seals are present over the length of the fit between the lance and the axial bore of the swing motor shaft in the region of the annular grooves of the lance. As a result, passes through the sliding bearing with a small gap from a small leakage, which serves the lubrication of the sliding bearing and separates the surfaces, whereby wear is counteracted.

In a further development of the invention, the lance has at its end an enlarged diameter head piece, with which it is mounted in the flange. As a result, a resilient attachment of the lance is made possible in the flange. For this purpose, the gap formed by the play between the lance and the flange part is preferably bridged by at least one O-ring. Against rotation, the lance can be secured by means of an engaging in the head piece dowel pin.

In a further embodiment of the invention, the swivel motor is designed as a single-wing or double-wing rotary piston rotary engine. Rotary piston pivot motors, also referred to as rotary vane pivot motors, generate torque directly through one or more vanes disposed on the swing motor shaft, which are pressurized with hydraulic oil under pressure. Depending on whether one or two wings are arranged on the swivel motor shaft, rotary swivel motors are referred to as single-leaf or double-leaf.

In one-winged design of the swivel motor, the swivel motor housing of the swivel motor is preferably designed as a circular segment-shaped imbalance. As a result, a space-optimized imbalance is formed by the swivel motor housing itself. The use of such a trained pivot motor in a vibration generator for construction machinery, a significant reduction in the required space is possible; In particular, no separate shaft is required for a phase shifter.

In a further development of the invention, the angle of rotation of the rotary vane of the single-pivoting pivot motor is limited by a respective stop surface of two arranged on the pivot motor housing stops, wherein between the two stops defined by the rotation angle pivot space of the rotary vane opposite at least one can be acted upon with oil oil pocket, wherein Oil supply of at least one oil pocket in addition to the supply channels of the two sides of the rotary vane pressure chambers arranged at least one separate channel is connected via an externally arranged on the lance ring groove with a opening into the at least one oil pocket supply bore of the hollow shaft. This achieves an at least partial compensation of the resulting force acting on the bearings. Since the swivel motor housing is designed as imbalance, the bearings with which the swivel motor housing is mounted on the swivel motor shaft, increasingly loaded with increasing speed by the centrifugal force. In addition, a bearing force results from the oil pressure in the chambers of the slewing motor. This resulting from centrifugal force and oil pressure in the chambers bearing load leads to an increased adjusting torque that is reduced by the provision of at least one oil bag. The arrangement of a separate channel for oil supply to the oil pocket, a hydraulic short circuit between the two chambers of the swing motor is excluded. Alternatively, two check valves or a shuttle valve may be arranged. Valves, however, are sensitive to dynamic loads, which are essential in a vibrator gearbox.

In a further development of the invention, the maximum pivot angle of the rotary wing is less than 180 °, preferably less than 160 °, preferably 150 ° or less. As a result, the largest possible imbalance is possible with low mass of the swivel motor housing. From the reduction of the known in the art swivel angle of 180 ° further results in the advantage that a provided for reducing the bearing force oil pocket over the circumference of the swing motor housing can be made longer. Similarly, an equally longer sealing distance between oil pocket and chambers of the swing motor can be formed. In addition, also the wing can be made higher, which at the same required adjusting torque and the same length of the chambers of the swing motor in the axial direction a lower required Pressure results. Accordingly, the resulting from the oil pressure in the chambers of the swing motor, the bearing load-increasing force component is reduced.

The invention further relates to a vibration exciter for construction machines, in particular vibratory rams, with at least one axis with at least two imbalance masses, in which a pivot motor of the aforementioned type for adjusting the rotational position of at least one imbalance mass is arranged. Characterized in that at least one imbalance mass is formed by the housing of a swing motor, the pivot motor shaft is arranged rotatably to this, a significant reduction of the required installation space is achieved, in particular, no separate shaft for a phase shifter is required.

In a further development of the invention, three unbalanced masses are arranged on at least one axis, the average imbalance mass formed by the circular segment-shaped pivot motor housing of the swivel motor, whose hollow shaft is part of the axis. As a result, an imbalance wave is achieved with adjustable resulting unbalance.

Figur 1

die schematische Darstellung eines Vibratorgetriebes mit drei Unwuchtwellen;

Figur 2

die Darstellung des Vibratorgetriebes aus Figur 1 in der Vorderansicht;

Figur 3

die Darstellung des Vibratorgetriebes aus Figur 1 in der Seitenansicht;

Figur 4

die Darstellung einer oberen Unwuchtwelle des Vibratorgetriebes aus Figur 1;

Figur 5

die Darstellung der Unwuchtwelle aus Figur 4 mit einem durch den Schwenkmotor verlaufenden Querschnitt;

Figur 6

die schematische Darstellung der Unwuchtwelle aus Figur 5 a) bei maximalem statischen Moment; b) bei reduzierten statischen Moment;

Figur 7

die schematische Darstellung der Unwuchtwelle aus Figur 4 im Längsschnitt mit eingebrachter feststehender Lanze zur Ölversorgung;

Figur 8

die Darstellung der Anordnung aus Figur 7 mit entferntem Flanschteil;

Figur 9

die schematische Darstellung der Lanze der Anordnung aus Figur 7 mit angeordnetem Flanschteil;

Figur 10

die schematische Darstellung des Schwenkmotors der Unwuchtwelle aus Figur 7 im Querschnitt und

Figur 11

die schematische Darstellung eines entsprechend der Anordnung gemäß Figur 10 ausgebildeten Schwenkmotors in einer Ausführungsform mit Öltasche.

Other developments and refinements of the invention are specified in the remaining subclaims. An embodiment of the invention is illustrated in the drawings and will be described in detail below. Show it:

FIG. 1

the schematic representation of a Vibratorgetriebes with three unbalanced shafts;

FIG. 2

the representation of the vibrator gearbox FIG. 1 in front view;

FIG. 3

the representation of the vibrator gearbox FIG. 1 in the side view;

FIG. 4

the representation of an upper imbalance shaft of the vibrator gear FIG. 1 ;

FIG. 5

the representation of the imbalance wave FIG. 4 with a running through the pivot motor cross-section;

FIG. 6

the schematic representation of the imbalance shaft FIG. 5 a) at maximum static moment; b) at reduced static moment;

FIG. 7

the schematic representation of the imbalance shaft FIG. 4 in longitudinal section with introduced fixed lance for oil supply;

FIG. 8

the representation of the arrangement FIG. 7 with the flange part removed;

FIG. 9

the schematic representation of the lance of the arrangement FIG. 7 with arranged flange part;

FIG. 10

the schematic representation of the swing motor of the imbalance shaft FIG. 7 in cross-section and

FIG. 11

the schematic representation of a according to the arrangement according to FIG. 10 trained swing motor in one embodiment with oil pocket.

The selected as an exemplary vibration exciter is designed as a three-shaft vibrator gear. There are three unbalanced shafts 1,1 'arranged, comprising an axis 2, on the spaced apart two outer imbalance masses 3 are arranged. On the respective opposite outer imbalance mass 3 arranged inside adjacent to the outer imbalance masses 3 each have a gear 4 is arranged on the axis 2. In the case of the outer imbalance shafts 1, a swivel motor 5 designed as a rotary swivel motor is arranged between the toothed wheels 4, the swivel motor shaft 51 of which is part of the axle 2. The central imbalance shaft 1 'has on its axis 2 between the gears 4 an inner imbalance mass 3'. The imbalance mass 3 'is dimensioned twice as wide as the outer imbalance masses. 3

The imbalance masses 3, 3 'are formed in a circular sector. The radius of the outer unbalance 3 of the outer unbalanced shafts 1 substantially corresponds to the radius of the gears 4. The radius of the outer imbalances 3 and the inner imbalance 3 'of the central imbalance shaft 3' is significantly greater than the radius of the gears 4 of the central imbalance shaft 1 ', which are larger in size than the gears 4 of the outer unbalanced shafts 1, between which a rotary piston pivot motor 5 is arranged.

The rotary piston pivot motor 5 is formed by a pivot motor shaft 51, which is part of the axis 2, and arranged on the pivot motor shaft 51 pivot motor housing 55. The swing motor shaft is provided in the exemplary embodiment with an axial bore 511, spaced from each other, two radial bores 512 led to the outside are. Externally, a rotary vane 52 is formed on the pivot motor shaft 51, which is arranged within the pivot space 55 formed by the inner contour 54 of the pivot motor housing 53.

The pivot motor housing 53 is formed according to the imbalance masses 3, 3 'as a sector-shaped unbalance. The pivot space 55 formed between the inner contour 54 of the pivot motor housing 53 and the pivot motor shaft 51 is limited by two stop surfaces 56, which allow a maximum rotation angle of 150 degrees. Between the abutment surfaces 56 of the pivot motor housing 53 and the rotary wing 52 of the pivot motor shaft 51, two chambers 57 are formed for the operation of the rotary piston pivot motor 5.

In the axial bore 511 of the pivot motor shaft 51, a lance 6 for supplying the chambers 57 of the rotary piston pivot motor 5 is introduced with hydraulic oil. The lance 6 is substantially cylindrical. At the end, the lance 6 has a head piece 61, which is adjoined by a shaft 62, which merges into a diameter-enlarged slide bearing portion 63. In the lance 6, two channels 64 are provided coaxially to the central axis 11 for supplying the chambers 57 of the rotary piston pivot motor 5. The channels 64 each open into an annular groove 65 arranged within the sliding bearing section 63, which is arranged such that one of the radial bores 512 is arranged as a pivoting motor 51 orthogonal thereto, which axial bore 511 connects to the respective chamber 57 of the rotary piston pivoting motor 5 represents. The sealing of the annular grooves 65 to the pivot motor shaft 51 via a very narrow gap between the sliding bearing portion 63 and the inner wall of the axial bore 511 of the pivot motor shaft 51, wherein the sliding bearing portion is provided in the embodiment with a sliding bearing coating made of plastic.

The lance 6 is mounted with its head piece 61 on a flange 7, which is fixed to the - not shown - housing of the vibrator gear. The flange part 7 consists essentially of a base plate 71, which is connected centrally with a cup-shaped recess 72 which is aligned with a bore 73 guided through the base plate 71. The cup-shaped recess 72 receives the lid part 75, which is provided with a centrally arranged cylindrically shaped recess 76 whose outer diameter is slightly larger than the outer diameter of the head piece 61 of the lance 6. The cover part 75 is provided with supply connections 77 for supplying the channels 64 the lance 6 received by the lid part 75 is provided. Furthermore, in the recess 76 of the cover part 75, a dowel pin 78 is arranged for engagement in an eccentrically arranged in the head piece of the lance 6 fitting hole 66. Surrounding the recess 72 of the cover part 75 are parallel to each other two annular grooves for receiving an O-ring 8 is introduced. The O-ring 8 bridges the gap between the head piece 61 of the lance 6 and the recess 76 of the cover part 75, whereby the head piece 61 is mounted slightly pivotable in the cover part 75. The cover part 75 is fixed in the recess 72 of the base plate 71 and receives the head piece 61 of the lance 6, whose shaft 62 projects through the bore 73 of the base plate into the axial bore 511 of the pivot motor shaft 51 of the rotary piston pivot motor 5. In this case, the cover part 75 is sealed relative to the cup-shaped recess 76 by means of an O-ring 81.

In the exemplary embodiment, the vibrator is operated by two - not shown - drives that drive the top and bottom unbalance shaft 1, which are identical to the pivot motor shafts 51 of the rotary piston pivot motor 5 here.

The entire static moment of the upper and lower imbalance shaft 1 corresponds to the static moment of the middle imbalance shaft 1 in this three-shaft vibrator Therefore, the imbalance 3 on the lower and upper imbalance shaft 1 does not claim the available space. In the upper and in the lower imbalance shaft 1 each have a rotary piston pivot motor 5 is integrated, which is located in each case in the middle imbalance. The pivot motor housing 53 of the rotary piston pivoting motor 5 is formed as a circular segment unbalanced mass and rotatably mounted on the respective unbalanced shaft 1. The angle of rotation is limited by the integrally formed on the pivot motor shaft 51 rotary vane 52 in interaction with the abutment surfaces 56 of the pivot space 55 to a maximum of 150 degrees. The rotary vane 52 also serves as a seal between the two chambers 57 which are delimited between the rotary vane 52 and the pivot motor housing 53 and the pivot motor shaft 51. The two chambers 57 are supplied with hydraulic oil, which is supplied via the radial bores 512 of the swing motor shaft 51. In order to supply the hydraulic oil to the rotating swing motor shaft 51, the fixed lance 6 is mounted in the central, axially extending bore 511. The sealing effect is achieved through narrow gaps. To prevent excessive leakage, the hydraulic transmission is equipped with two rotary actuators, which ensures low pressure operation while ensuring the required maximum torque of the swing motors.

The hydraulic oil is supplied through the supply ports 77 to the channels 64 of the lance 6. From these channels 64, the oil enters the annular grooves 65 on the outside of the lance. The chambers 57 of the rotary piston pivot motor 5 are connected by radial bores 512, which connect the respective annular groove space with the corresponding chamber 57. The sealing of the annular grooves 65 against each other via a narrow gap. In the embodiment, a Leckageringnut 67 is disposed between the two annular grooves 65, which serves to dissipate occurring leak oil. The fit between the lance 6 and the axial bore 511 of the pivot motor shaft 51 is designed in the region of the annular grooves 65, 67 as a narrow slide bearing. In this area, the lance is provided with a sliding bearing coating made of plastic. Due to the sliding bearing formed between the axial bore 511 of the pivot motor shaft 51 and the sliding bearing portion 63 of the lance 6, some leakage occurs, but at the same time lubricates the bearing, separates the surfaces and thereby counteracts wear.

Characterized in that the pivot motor housing 53 of the rotary vane pivot motor 5 is formed in each case as imbalance, the bearings with which the pivot motor housing 53 is mounted on the pivot motor shaft 51, with increasing speed increasingly burdened by centrifugal force. In addition, a bearing force results from the oil pressure in the chambers 57. This, resulting from centrifugal force and oil pressure in the chambers 57 bearing load leads to an increased adjusting torque. In order to at least partially compensate for the resultant force acting on the bearings, an oil pocket 58, which can be acted upon by oil pressure, can additionally be introduced into the swivel motor housing 53 (cf. FIG. 11 ). This oil pressure can be diverted, for example, in the control of the chambers 57. In this case, two check valves or a shuttle valve are required to preclude a hydraulic short circuit between the two chambers 57. Valves, however, are sensitive to dynamic loads, which are essential in a vibrator gearbox. In order to avoid valves on the swivel motor and to be able to select the oil pressure in the oil pocket 58 independently of the adjustment pressure of the rotary vane rotary motor 5, it makes sense to realize the oil supply in the oil pocket 58 via a separate connection. For example, for this purpose, the middle connection formed by the Leckageringnut 67 can be used.

Claims (15)

Swing motor, in particular for a vibration exciter for construction machines, with a swivel motor housing which is rotatably mounted on a swivel motor shaft, wherein at least two pressure chambers are arranged to act on a hydraulic oil, via which the swivel motor is operable, characterized in that the swivel motor shaft (51) an axial bore (511) is provided, in which a non-rotatably mounted lance (6) projects through which at least two channels (64) for oil supply to the pivot motor (5) are guided, which are spaced apart on the outside of the lance (6) at least partially circumferential annular grooves (65) open, wherein in the pivot motor shaft (51) radial bores (512) for connecting the at least two annular grooves (65) of the lance (6) with the at least two pressure chambers (57) are introduced. Pivoting motor according to claim 1, characterized in that the fit between the lance (6) and the axial bore (511) of the pivoting motor shaft (51) in the region of the annular grooves (65) of the lance (6) is designed as a narrow slide bearing. Pivoting motor according to claim 1 or 2, characterized in that the lance (6) is provided in the region of the annular grooves (65) with a plastic coating, which is preferably formed from Teflon. Pivoting motor according to one of claims 1 to 3, characterized in that the lance (6) in the region of the shaft (62) is formed reduced in diameter, whereby the elasticity is increased. Pivoting motor according to one of claims 1 to 4, characterized in that the lance (6) is end mounted with play in a flange (7). Pivoting motor according to claim 5, characterized in that the lance (6) end has an enlarged diameter head piece (61) with which it is mounted in the flange part (7). Pivoting motor according to claim 5 or 6, characterized in that the clearance formed by the clearance between the lance (6) and the flange part (7) is bridged by at least one O-ring (8). Pivoting motor according to claim 8, characterized in that the rotation is effected by at least one eccentric axially in the lance (6) projecting dowel pin (78). Pivoting motor according to one of the preceding claims, characterized in that for sealing the swivel motor housing (53) relative to the swivel motor shaft (51) no seals are arranged, wherein the sealing effect is effected exclusively on the gap. Pivoting motor according to one of claims 2 to 9, characterized in that over the length of the fit between the lance (6) and axial bore (511) of the pivot motor shaft (51) in the region of the annular grooves (65) of the lance (6) no sliding seals available are. Pivoting motor according to claim 10, characterized in that the pivoting motor is a single-wing or double-wing rotary piston pivot motor. Pivoting motor according to one of the preceding claims, characterized in that the swivel motor housing (53) is designed as a circular segment-shaped imbalance, wherein the swivel motor (5) is formed single-wing. Pivoting motor according to claim 12, characterized in that the angle of rotation of the rotary vane (52) is limited by two abutment surfaces (56) arranged on the swivel motor housing (53), wherein between the two abutment surfaces (56) the swivel space (55) of the swivel space defined by the rotational angle Rotary vane (52) opposite at least one acted upon with oil oil pocket (58) is formed, wherein for oil supply of at least an oil pocket (58) in addition to the supply channels of both sides of the rotary vane (52) arranged chambers (57) at least one separate channel is arranged, via an externally arranged on the lance annular groove (67) with a in the at least one oil pocket (58) opening supply bore of the hollow shaft is connected. Vibration generator for construction machines, in particular for vibratory ramming, with at least one axis with at least two imbalance masses, characterized in that a pivot motor (5) according to one of the preceding claims for adjusting the rotational position of at least one imbalance mass is arranged. Vibration generator according to claim 14, characterized in that three unbalance masses are arranged on at least one axis, whose average unbalanced mass is formed by the swivel motor housing (53) of the swivel motor (5) according to claim 12 or 13, the swivel motor shaft (51) is part of the axis.

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