Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B17/00—Pumps characterised by combination with, or adaptation to, specific driving engines or motors
  • F04B17/03—Pumps characterised by combination with, or adaptation to, specific driving engines or motors driven by electric motors
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
  • F04B1/12—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
  • F04B1/14—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having stationary cylinders
  • F04B1/141—Details or component parts
  • F04B1/146—Swash plates; Actuating elements

Definitions

• the invention relates to an axial piston pump with a plurality of pistons distributed on an arc of a circle, which can be pressed into a cylinder bore and spring-loaded by a common drive element arranged on an axially parallel to the piston axes and performing a wobbling movement.
• Such axial piston pumps have already become known in various designs.
• Such a known embodiment sieves in the axial direction of the pump cylinder in which pistons are guided in a sealed manner. At their outer ends, the pistons rest on a swash plate which is driven by a power source via a shaft.
• Each piston is provided with a return spring that presses it positively against the swashplate.
• problems arise on the one hand because of the friction between the swash plate and the piston ends and the resulting operating noise, and on the other hand there are problems with regard to the mounting of the drive shaft of the swash plate and also the mutual exact alignment of the drive shaft of the swash plate and the pistons.
• the invention has for its object to provide a way to reduce the friction between the drive element and the piston and a much better bearing of the drive shaft for the drive element.
• the drive element for the pistons is designed as a ring, disk or the like which is rotatable relative to the drive shaft about an axis running at an acute angle to the axis of the drive shaft, that the drive shaft holds the ring, the disk or the like. protrudes in the axial direction on the side facing away from a drive motor and that an assembly block having the piston cylinders is designed as a bearing part for the end of the drive shaft which projects over the ring, the disk or the like.
• the drive shaft is supported by the Axial piston pump an essential feature. If the possibility is created by the invention to put the drive element for the pistons practically between two bearing points, then this results in a significant improvement and a particularly smooth running. As a particular advantage, however, it can be said that the measures according to the invention create a particularly compact design, so that not only the axial piston pump itself but also the associated drive motor as a whole only require a small space.
• FIG. 1 shows a longitudinal section through an axial piston pump of the type according to the invention with an associated drive motor;
• Figure 2 is a view of the mounting block receiving the piston cylinder and the bearing seen from the piston side.
• 3 shows a section along the line I - I in Fig. 2.
• 4 shows a section along the line II-II in FIG. 3 and
• FIG. 5 shows a section along the line III-III in FIG. 3.
• the axial piston pump shown consists essentially of a mounting block 1, in which piston cylinders 2 are incorporated, the piston 3, a drive element 4 for actuating the pistons 3, a drive shaft 5 for the drive element 4 and a drive motor 6.
• the axes of the pistons 3 are aligned axially parallel to the axis of the drive shaft 5, so that by a wobbling movement of the drive element 4 which arises when the drive shaft 5 rotates, the pistons 3, which are distributed along a circular arc, are pressed into the piston cylinder 2 in the mounting block 1 or by the arrangement of peders 7 are in turn returned.
• the drive element is designed as an axial thrust bearing. From a design point of view, this is the simplest embodiment since it can be used to arrange a commercially available part.
• the drive shaft 5 has an acute angle to
• an axial thrust bearing is therefore provided, the inner ring 9 and the outer ring 10 forming corresponding support shoulders 11 and 12 for the balls 13 in the bearing.
• the outer ring can always be designed as a corresponding drive element. It is of course also possible to arrange a corresponding disk or a further ring on the outer ring 10, which will be particularly useful in this case. if the pistons 3 lie on a circle of relatively large diameter.
• the drive motor 6 is expediently accommodated in a pot-shaped housing 15, the mounting block 1 being attachable to the open end face of this housing 15.
• a self-contained housing can be created which accommodates the motor 6, the drive element 4, the pistons 3 and the piston cylinders 2 and the entire bearing of the drive shaft 5.
• the open end face of the housing 15 and the mounting block 1 have corresponding threaded sections 16, so that the mounting block 1 can thus be screwed into the pot-shaped housing 15 by means of a rotary movement.
• both on the housing 15 and on the assembly block 1 mounting flanges to be arranged so that a mutual screwing is possible by several screws arranged in the axial direction.
• a sealing ring 17 can be used with such a connection, which is arranged in the contact or screwing area between the mounting block 1 and the housing 15.
• the end of the drive shaft 5 facing away from the mounting block 1 is held in an axial pressure bearing 19 at the base of the pot-shaped housing 15.
• This bearing also has to absorb the corresponding axial forces which result from a pumping movement.
• the drive shaft 5, that is, the stub shaft 14, can be mounted in the mounting block 1 by one or two radial bearings 20, a spring 21 being inserted between the outer end face of the radial bearing 20 and the mounting block 1.
• This spring 21 has the effect that, when the mounting block 1 is screwed into the housing 15, the drive shaft 5 remains in the exact position and cannot move the radial bearing 20 when screwing it together. This also eliminates axial play, which still contributes significantly to increasing the smoothness.
• the embodiment with two or more disc springs, which then form the spring 21 as a whole, is particularly simple.
• each piston 3 is an Ab support body 22 is used, the support body 22 and the end of each piston 3 facing this have corresponding spherical dome-shaped elevations or depressions.
• the piston 3 is practically always supported on the ring 10 over a large area, so that the mutual wear is practically completely prevented.
• the piston ends abutting the swash plates are usually hemispherical, so that practically only one punctiform support was given between the end of the piston and the swash plate. In the embodiment shown in Fig. 1, however, there is always a large contact surface between the ring 10 and the support body 22 and thus the piston 3.
• the support body 22 is equipped with a spherical cap-shaped elevation and the piston 3 has the corresponding recess.
• the reverse arrangement is of course also possible.
• the support body 22 is provided with a correspondingly large diameter so that a large-area support is possible and the slight radial movements can also be compensated for. It is therefore also expedient if the end of the pistons 3 facing the drive element 4 is equipped with a pad 23 which has a larger diameter than the pistons 3.
• a correspondingly large recess in the form of a spherical cap can be provided in the region of this flange 23.
• the pistons are supported by helical compression springs 7 against the mounting block 1. It is particularly important that the mounting block-side end of the springs 7 engage in ring grooves 24 in the mounting block 1 which extend coaxially to the piston cylinder 2. This configuration creates the possibility that the piston 3 practically up to the stop of the flange 23 in the Piston cylinder 2 can be pushed in without the spring 7 narrowing this displacement range. Furthermore, this has the advantage that the guide for the piston 3 is significantly lengthened, so that it is easily possible, as will be explained later, to manufacture the entire mounting block 1 from aluminum without using separate bushings for the piston cylinder 2 ought to. In known designs, 2 enlarged bores, in which the springs engage, are connected directly to the bores for the piston cylinders.
• the assembly block is also particularly simple in terms of production, since it can be manufactured as a rotationally symmetrical turned part. It is thereby also possible to use practically the same assembly block 1 in the housing 15 of drive motors 6 of different strengths. If the diameter of the housing 15 then becomes larger, only the outer region of the mounting block 1, which therefore carries the thread 16, has to be manufactured with a larger diameter.
• the axial bores for the piston cylinders 2 an axial bore 26 for receiving the bearings 20 and axial connecting bores 27 are provided, which in turn are intended to connect different radial bores to one another.
• threaded bores 28 are provided in the axial direction, which are used to fasten the entire unit formed from the housing and assembly block 1 to a machine part.
• connection bores 29 and 30 are provided, the axes of which lie in a plane transverse to the longitudinal axis of the mounting block 1.
• These connecting bores 29, 30 and 27 are used for the mutual connec tion of the pressure chambers and the suction lines of the individual piston-cylinder units.
• the free, outwardly opening ends of the connecting bores 30 are designed with a slightly enlarged diameter, and closure pieces 32 can be inserted into these outward-opening ends that are not required.
• closure pieces are designed as cup-shaped parts, into which a spherical body is then hammered from the outside. Adequate sealing and fastening is thereby achieved.
• the bores 33 extending from the rear of the mounting block 1 represent the suction openings, it being possible to leave only one such bore 33 open and to close the remaining bores by covering caps. These holes 33 are interconnected by the connecting holes 29.
• An intake valve 35 is provided between the bores 33 and the piston cylinder 2, the valve seat 36 being fastened by appropriate deformation of the edge region 37 of the bore 53.
• Check valves 38 are inserted into the connecting bores 30, which open during the pumping process through the pistons 3 and close again during the suction process.
• the pressure chambers are in turn connected to one another via the connecting bores 33 within the mounting block 1, with these valves 38 being used in each case. These connecting lines 30 then open into an axial bore 39, which opens into a further radial bore 40.
• this assembly block 1 can be made entirely of aluminum, which of course has a significant advantage in processing (turning, drilling, etc.).
• the electrical connections 45 must of course also be led through the housing 15 in a tight arrangement to the outside. Of course, this is not a particular problem.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Reciprocating Pumps (AREA)

Priority Applications (1)

Applications Claiming Priority (1)

Publications (1)

Family

ID=3539385

Family Applications (1)

Country Status (5)

Cited By (9)

Citations (5)

• 1983
  • 1983-06-28 ZA ZA834713A patent/ZA834713B/xx unknown
  • 1983-07-06 IT IT67734/83A patent/IT1205388B/it active
  • 1983-07-08 WO PCT/EP1983/000180 patent/WO1984000403A1/de unknown
  • 1983-07-08 EP EP83902097A patent/EP0113366A1/de not_active Withdrawn
  • 1983-07-12 ES ES524071A patent/ES524071A0/es active Granted

Patent Citations (5)

Also Published As

Similar Documents

Legal Events