JP2014095384A - Axial piston machine with swash plate structure - Google Patents

Abstract

An object of the present invention is to provide a slide shoe pressing device capable of generating a high pressing force of a slide shoe, improved in terms of structural labor and assembly labor, and not accompanied by weakening of a tooth row between a cylinder block and a drive shaft. provide.
A retainer plate 30 is formed as a disc spring-like spring element 31, and the spring element 31 is supported jointly on a cylinder block 2 on an inner peripheral surface. There is no additional pressing spring for generating a pressing force acting on the.
[Selection] Figure 1

Description

  The present invention relates to an axial piston machine having a swash plate structure, and the axial piston machine includes a cylinder block arranged to be rotatable about a rotation axis, and the cylinder block includes at least one piston cutting machine. Each drive mechanism piston is slidably disposed in the longitudinal direction of the piston notch, and each drive mechanism piston is supported by the stroke disk by one slide shoe. A swash plate provided with a retainer plate that is operatively coupled to the slide shoe and that rotates in synchronization with the cylinder block, and the retainer plate protects the slide shoe from lifting from the stroke disc The present invention relates to a structural axial piston machine.

  In such an axial piston machine having a hydrostatic swash plate structure, a drive mechanism piston is supported by a stroke disc for generating a stroke by a slide shoe arranged in a joint manner on the drive mechanism piston. In order to reliably operate an axial piston machine having a swash plate structure, it is necessary to ensure that the sliding surface of the slide shoe attached to the drive mechanism piston in a joint manner always contacts the sliding surface of the stroke disk. For this reason, in the case of an axial piston machine with a higher power density, a thrust sliding bearing is formed between the slide shoe and the stroke disk, the load being reduced statically. A pressure pocket is formed in the slide shoe. This pressure pocket is connected to a corresponding displacement chamber via a hole provided in the drive mechanism piston. The pressing force is related to the pressure of the pressure medium formed in the displacement chamber. However, during the suction operation of the axial piston machine or during the occurrence of increased friction in the drive mechanism piston, for example when contaminated particles pass through the piston notch of the cylinder block, the force that lifts the slide shoe from the sliding surface of the stroke disc May act on the slide shoe. If the slide shoe is lifted from the sliding surface of the stroke disk, the suction volume flow of the axial piston machine will be interrupted, and the stroke disk will be commensurate with the transition from the suction side on the low pressure side to the pumping side on the high pressure side. There is a risk that a slide shoe lifted with a large lift amount will violently collide with the stroke disc. As a result, the slide shoe, the drive mechanism piston, and the stroke disk are damaged.

  In order to prevent such lifting of the slide shoe from the stroke disc in an axial piston machine, fixed pressers are already known. In this known holding device, the retainer plate is fixed axially in the housing directly in the housing or by an additional retaining ring or additional retaining plates. Such a fixed pressing device is known from German Patent No. 4,040,313 and German Patent Application No. 102005047981 and allows a high pressing force of the slide shoe. Due to manufacturing and assembly, the slide shoe can be lifted from the stroke disk between the housing or the holding ring fixed to the housing or the holding plate fixed to the housing and the contact surface of the retainer plate. A certain amount of axial play is required. However, such a fixed pressing device has a high structural effort. This is because bearing discs of different thicknesses are pre-held on the stroke disc, slide shoe, holding ring or holding plate or retainer plate to compensate for component errors and spacing errors and limit axial play. Because it must be. In addition, the housing must be mechanically machined in order to produce a corresponding contact surface for the purpose of receiving and fixing the retainer plate or retaining ring or retaining plate. As long as the retainer plate is fixed to the housing by one retaining ring or a plurality of retaining plates, the additional components formed by the retaining ring or retaining plate further increase the construction effort. Furthermore, in the case of such a fixed pressing device, a high assembling time is required. This is because, in the case of an axial piston machine having a stroke disk integrally formed in the housing, before the cylinder block is assembled and assembled in the housing, a slide shoe attached jointly to the drive mechanism piston is moved by the retainer plate. This is because the stroke disk is fixed inside the housing. This known example requires time-consuming introduction and insertion of the drive mechanism piston into the piston notch of the cylinder block within the housing surrounding the cylinder block of the axial piston machine.

  In the axial piston machine, a spring-elastic pressing device that can be formed without play is already known as an alternative to such a fixed pressing device. Such a spring-elastic pressing device is known, for example, from German Offenlegungsschrift 3,222,210. In such a known spring-elastic pressing device, the spring force of the compression spring arranged radially between the drive shaft and the cylinder block that presses the cylinder block against the control surface is evenly distributed over the entire circumference. And a plurality of pins and a single disk with a crown-shaped outer surface on which the crown-shaped inner surface of the retainer plate is supported are transmitted to the retainer plate. Since the compression spring that presses the cylinder block against the control disc is used to press the slide shoe against the stroke disc at the same time, such a spring elastic pressing device has a large pressing force of the slide shoe. It is characterized by being restricted to. In the case of axial piston machines with higher power density, the built-in space for the pins in the range of the cylinder block neck with teeth that non-rotatably couple the cylinder block to the drive shaft and the control surface of the cylinder block The built-in space for the compression spring that presses against is greatly limited. Therefore, in the case of such an axial piston machine, the pin is arranged by omitting a plurality of teeth in the cylinder block or the drive shaft tooth row as a built-in space for the pin that transmits the spring force of the compression spring to the retainer plate. It is necessary to provide a hole to be formed in the range of the cylinder block neck. However, the omission of a plurality of teeth in the tooth row between the drive shaft and the cylinder block and the required hole provided in the cylinder block neck of the cylinder block limit the possibility of transmission of the maximum torque. . This is because a lack of a plurality of teeth increases the load applied to the remaining teeth of the dentition, and the holes weaken the cylinder block neck in the dentition range.

German Patent No. 4040313 German Patent Application Publication No. 102005047981 German Patent Application Publication No. 3222210

  An object of the present invention is to improve the axial piston machine described at the beginning to generate a high pressing force of the slide shoe, which is improved in terms of structural labor and assembly labor. It is an object of the present invention to provide a slide shoe pressing device that does not involve weakening of the dentition therebetween.

  In order to solve this problem, in the axial piston machine according to the present invention, the retainer plate is formed as a disc spring-like spring element, and the spring element is supported by the cylinder block on the inner peripheral surface in a joint manner. In this case, an additional pressing spring for generating a pressing force acting on the retainer plate is not provided.

  In an advantageous aspect of the axial piston machine according to the present invention, the retainer plate is provided with a spherical crown portion on the inner peripheral surface for joint support to the cylinder block, and the spherical crown portion is provided on the cylinder block. It is supported by a provided spherical crown cylinder block neck.

  In an advantageous embodiment of the axial piston machine according to the invention, the retainer plate is in contact with the slide shoe without play.

  In an advantageous aspect of the axial piston machine according to the invention, the spring characteristic line of the retainer plate has a characteristic line range with a region of change of the gentle slope of the spring characteristic line, the characteristic line range being an axial line. After assembly of the piston machine, automatic error compensation of the retainer plate, the cylinder block, and the slide shoe is enabled at the assembly position.

  In an advantageous aspect of the axial piston machine according to the present invention, the retainer plates each have a hole-like notch for accommodating a slide shoe neck of one slide shoe, and the retainer plate is located in the range of the notch. A plurality of spring teeth directed inward and directed to the slide shoe plate of the slide shoe.

  In an advantageous embodiment of the axial piston machine according to the invention, the retainer plate is formed as a disc spring with a slit.

  In an advantageous embodiment of the axial piston machine according to the invention, the retainer plate comprises a plurality of spring tongues directed radially outwards, each having a slide shoe slide between the two spring tongues. One notch is formed to accommodate the shoe neck.

  In an advantageous embodiment of the axial piston machine according to the invention, the retainer plate has a characteristic line range with a sudden rise region of the spring force immediately followed by a characteristic line range with a slowly changing region of the spring characteristic line. Have.

  In an advantageous embodiment of the axial piston machine according to the invention, the retainer plate is adapted so that the slide shoe is applied to the disc segment of the retainer plate with the slide shoe plate after a defined lifting amount of the slide shoe from the stroke disc. Is formed.

  In an advantageous embodiment of the axial piston machine according to the invention, the cylinder block, the slide shoe and the retainer plate are formed as a pre-assembled drive mechanism assembly which can be assembled in the housing of the axial piston machine. .

  In an advantageous embodiment of the axial piston machine according to the invention, an additional pressing spring is provided for generating a pressing force that presses the cylinder block against the control surface.

  In an advantageous embodiment of the axial piston machine according to the invention, the pressing spring is supported on the drive shaft of the axial piston machine on the first side and on the cylinder block on the second side.

  The axial piston machine according to the present invention includes a spring elastic pressing device for the slide shoe. In the present invention, the retainer plate is formed as a spring elastic element, and the retainer plate formed as a disc spring generates a pressing force of the slide shoe. Therefore, the pressing device is formed as a disc spring. This disc spring is supported jointly on the cylinder block on the inner peripheral surface, so that the spring force generated by the retainer plate directly presses the slide shoe. An additional pressing spring for generating a force and transmitting this pressing force to the retainer plate becomes unnecessary. Furthermore, a retainer plate formed as a disc spring can easily generate a high pressing force of the slide shoe. Compared to known fixed pressing devices based on the known prior art, the pressing devices in the present invention have reduced structural and assembly efforts. This is because the housing does not require an abutment surface for accommodating the retainer plate, an abutment surface for one retaining ring that retains the retainer plate, or an abutment surface for a plurality of retaining plates that retain the retainer plate. This is because the components can be omitted. The spring force of the compression spring of the cylinder block is transmitted to the retainer plate by a pin beyond the tooth row between the cylinder block and the drive shaft. The pressing device has a pressing force against the slide shoe, which is increased by the spring force of a retainer plate formed as a disc spring. Furthermore, in the retainer plate according to the present invention formed as a disc spring, a pin for transmitting the spring force of the compression spring that is arranged inside the cylinder block and presses the cylinder block against the control surface becomes unnecessary. In the axial piston machine according to the above, the weakening of the tooth row between the cylinder block and the drive shaft and the weakening in the range of the cylinder block neck of the cylinder block do not occur.

  According to an advantageous aspect of the present invention, the retainer plate is provided with a spherical crown on the inner peripheral surface for joint-type support to the cylinder block, and the spherical crown is provided on the cylinder block. It is supported by a spherical crown cylinder block neck. An axial piston having a variable displacement volume even in an axial piston machine having a constant displacement volume due to the spherical shape at the cylinder block neck of the cylinder block and the corresponding spherical crown shape at the inner surface of the retainer plate formed as a spring Even in the machine, the joint-type support of the retainer plate formed as a disc spring on the cylinder block can be achieved with little manufacturing effort.

  A special advantage is obtained according to the refinement of the invention when the retainer plate is in contact with the slide shoe without play. Furthermore, as long as the retainer plate formed as a disc spring supported by the cylinder block is in contact with the slide shoe plate of the slide shoe without play, it is generated by the spring force of the retainer plate formed elastically. The holding force of the slide shoe is also transmitted to the cylinder block at the same time. This achieves basic pressing of the cylinder block against the control surface of the axial piston machine and avoids tilting of the cylinder block from the control surface. Accordingly, it is possible to omit an additional compression spring that presses the cylinder block against the control surface, whereby the basic pressing of the cylinder block can be performed by the pressing device according to the present invention having the retainer plate formed elastically. This is possible by structurally simple means without the use of further components.

  A special advantage is that, according to the improved embodiment of the invention, the spring characteristic line of the retainer plate has a characteristic line range with a region of change of the gentle slope of the spring characteristic line, the characteristic line range being This is obtained when automatic error compensation of the retainer plate, the cylinder block and the slide shoe is enabled at the assembly position after the assembly of the axial piston machine. The retainer plate formed as a disc spring makes it possible to easily adapt the spring characteristic lines of the retainer plate formed in a spring-elastic manner to the requirements imposed by the corresponding structural configuration of the retainer plate. The spring elastically formed retainer plate has a gentle slope characteristic line range with a gentle slope of the spring force or with a horizontal change region, and after the axial piston machine is assembled, As long as the assembly position of the component is given in the characteristic line range, further adjustment of the spring characteristic line by a slowly inclined or horizontal change area where the retainer plate has only a slight change in spring force Without error compensation of peripheral components, especially the gap error between the mounting surface of the spring elastic retainer plate on the cylinder block and the mounting surface of the spring elastic retainer plate on the slide shoe plate of the slide shoe. Compensation as well as compensation for errors in the spring-elastic retainer plate itself can be performed. Therefore, the retainer plate formed in a spring-elastic manner makes it possible to automatically compensate for the spacing error in the characteristic range of a gentle slope where the spring force changes only slightly. This further reduces the structure labor. This is because, in comparison with known fixed pressing devices based on the known prior art, bearing discs or slide shoes or different retainer plates of different thicknesses are not required to compensate for the component spacing error. is there.

  According to an advantageous aspect of the present invention, the retainer plates each have a hole-like notch for receiving a slide shoe neck of one slide shoe, and the retainer plate is located inwardly within the range of the notch. A plurality of spring teeth directed and directed to the slide shoe plate of the slide shoe. With such spring teeth where the slide shoe comes into contact with the slide shoe plate without play, the characteristic line range with a gentle slope change area of the spring characteristic line is reduced compared to the retainer plate formed as a disc spring. Can be obtained at

  According to an alternative aspect of the invention, the retainer plate is formed as a disc spring with a slit. By using such a disc spring with a slit as the retainer plate, the characteristic line range with a gentle slope change region of the spring characteristic line can be reduced with less structural effort compared to the retainer plate formed as a disc spring. Can be obtained.

  For less structural effort, the retainer plate with slits has a plurality of spring tongues directed radially outwards, each holding a slide shoe neck for one slide shoe between the two spring tongues It is advantageous if one notch is formed for this purpose. Accordingly, in the retainer plate having a slit, a notch for accommodating the slide shoe neck of the slide shoe can be easily formed. The slide shoe is a slide shoe plate, and two spring tongues adjacent to each other. Can be placed between. Therefore, the slide shoe is in contact with the spring tongue without play by the slide shoe plate.

  According to an aspect of the present invention, the retainer plate has a characteristic line range with a sudden force increase immediately following the characteristic line range with a slowly changing region of the spring characteristic line. As a result, after the characteristic line range of the gentle inclination is exceeded, a force that lifts the slide shoe from the stroke disk causes a slight lift of the sliding surface of the slide shoe from the stroke disk, and is then generated by the spring elastic retainer plate. As a result, a rapid increase in the spring force is generated, and as a result, a high pressing force can be generated on the slide shoe. Therefore, such a characteristic line range having a sudden force increase can generate a high pressing force by the spring elastic retainer plate, and can limit the amount of lift of the slide shoe from the stroke disk. . This can reduce the risk of damage to the slide shoe and the stroke disc. The increased holding force can be generated only when the slide shoe is lifted from the stroke disk by the retainer plate formed as a disc spring, so that during normal operation of the axial piston machine, Friction with the stroke disk can be reduced. Therefore, the axial piston machine according to the present invention with the spring-elastic retainer plate due to the reduction of friction between the slide shoe and the stroke disc has reduced wear on the slide shoe and reduced power loss. And have.

  Such a characteristic line range with a sudden force increase in the retainer plate, according to an aspect of the invention, is that the slide shoe is a retainer on the slide shoe plate after a defined lifting amount of the slide shoe from the stroke disc. It can be obtained with less structural effort when the retainer plate is formed to be applied to the disk segment of the plate. Thus, after the spring deflection of the spring teeth or tongues, the slide shoe is applied to the disc segment of the retainer plate with the corresponding slide shoe plate, so that after the prescribed lift amount of the slide shoe, A sudden force increase can be easily obtained.

  Further, the retainer plate according to the present invention formed in a spring-elastic manner forms the cylinder block, the slide shoe, and the retainer plate as a pre-assembled drive mechanism assembly that can be assembled in the housing of the axial piston machine. It becomes possible to do. Compared with a known fixed presser device, the retainer plate according to the present invention drives a drive mechanism assembly comprising a cylinder block, a slide shoe, and a retainer plate, and a stroke disk of an axial piston machine is integrally formed. It can be easily and compactly assembled in the housing surrounding the mechanism assembly. Compared to a known axial piston machine with a fixed pressing device, labor-intensive and time-consuming introduction and insertion of the drive mechanism piston into the piston notch of the cylinder block inside the housing is eliminated. Thereby, the axial piston machine according to the invention has a simple assembly and a reduced manufacturing cost due to this.

  According to an improved aspect of the invention, an additional pressing spring is provided that generates a pressing force that presses the cylinder block against the control surface. A spring-elastic retainer plate protects the slide shoe against lifting from the stroke disc and leads to the basic pressing of the cylinder block against the control surface, with no play formed by the spring-elastic retainer plate The axial piston machine according to the invention with a pressing device may be provided with an additional pressing spring that presses the cylinder block against the control surface and is preferably incorporated between the drive shaft and the cylinder block. In the axial piston machine according to the present invention, the retainer plate formed in a spring elastic manner according to the present invention, compared with the axial piston machine having a spring elastic presser device in the known prior art, presses the pressing force and thus the slide shoe. The force can be generated regardless of the pressing spring that presses the cylinder block against the control surface, which can intentionally reduce the frictional force applied to the slide shoe, and is a spring-elastic force applied to the cylinder block. Due to the reaction force of the retainer plate formed on the cylinder surface, the cylinder block can be pressed against the control surface. In the axial piston machine according to the present invention, the pressing force of the cylinder block applied to the control surface is formed from the spring force of the retainer plate formed as a spring and the spring force of the additional pressing spring. The pressing force generated by the pressing spring is reduced without changing the pressing force of the cylinder block applied to the control surface, and the pressing spring is thus reduced and formed with a smaller size compared to known axial piston machines. Is possible. Therefore, as long as the pressing spring is incorporated radially between the drive shaft and the cylinder block inside the cylinder block, the additional pressing spring requires less installation space in the cylinder block.

  For this purpose, the pressing spring is advantageously supported on the drive shaft of the axial piston machine on the first side and on the cylinder block on the second side. With such a pressing spring disposed in the radial direction between the drive shaft and the cylinder block, a pressing force for pressing the cylinder block against the control surface can be easily generated in the cylinder block.

  Further advantages and details of the invention are explained in detail on the basis of several embodiments shown in schematic form.

1 is a longitudinal sectional view of a first embodiment of an axial piston machine according to the present invention. It is an enlarged view of the division X shown in FIG. It is sectional drawing along the AA line shown in FIG. FIG. 4 is a perspective view of a retainer plate of the axial piston machine shown in FIGS. 1 to 3. It is a figure which shows the spring characteristic line of the retainer plate shown in FIGS. It is a figure which compares the assembly method of the well-known prior art axial piston machine provided with the fixed pressing device, and the assembly method of the axial piston machine which concerns on this invention. It is a longitudinal cross-sectional view of 2nd Embodiment of the axial piston machine which concerns on this invention. It is sectional drawing along the BB line shown in FIG. 7, and the enlarged view of the division Y. FIG. 9 is a perspective view of a retainer plate of the axial piston machine shown in FIGS. 7 and 8. It is a figure which shows the spring characteristic line of the retainer plate shown in FIGS. It is a figure which shows the improvement form of the axial piston machine which concerns on this invention.

  In the following, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a longitudinal sectional view of an axial piston machine 1 having a hydrostatic swash plate structure according to the present invention.

  This axial piston machine 1 has a cylinder block 2 arranged so as to be rotatable about a rotation axis D. The cylinder block 2 includes a plurality of notches 3 for pistons arranged concentrically with respect to the rotation axis D. These piston notches 3 are preferably formed by cylinder holes. Further, one drive mechanism piston 4 is supported in the notch 3 for piston so as to be slidable in the longitudinal direction.

  The cylinder block 2 is supported by a control surface 5 that is stationary with respect to the housing 7 at one end surface in the axial direction. The control surface 5 is formed on a disc-like control member 6 on the bottom side. The control member 6 is fixed to the housing 7 or to a corresponding housing cover 7a of the housing 7 so as not to be relatively rotatable. The control member 6 is provided with a plurality of control slits in the form of kidneys or bowls. These control slits constitute an inflow port 8 and an outflow port 9. The piston notch 3 is provided on the end face side of the cylinder block 2 with one connection passage 10 preferably in the form of a kidney or a saddle, so that the drive mechanism piston 4 and the piston notch 3 The formed displacement chamber is alternately connected to the inflow port 8 and the outflow port 9 when the cylinder block 2 rotates about the rotation axis D.

  The cylinder block 2 is penetrated by a central hole. By this hole, the drive shaft 15 arranged concentrically with the rotation axis D is guided through the cylinder block 2. The drive shaft 15 is rotatably supported by bearings 16 and 17 on the housing 7 and the housing cover 7a. The cylinder block 2 is coupled to the drive shaft 15 so as to be rotationally synchronized, that is, is coupled so as not to be relatively rotatable. It is combined as possible. The cylinder block neck is integrally formed with the cylinder block 2 and extends in the axial direction toward the stroke disk 19.

  The drive mechanism piston 4 is disposed in a range in which the drive mechanism piston 4 protrudes beyond the cylinder block 2 and is inclined with respect to the rotation axis D by a single support element formed as a slide shoe 20. For example, it is supported by a swash plate. In the illustrated embodiment, the stroke disk 19 is directly formed integrally with the housing 7. The axial piston machine 1 has a constant displacement volume. In the illustrated embodiment, a bearing disk 21 attached to the stroke disk 19 is further shown. The slide shoe 20 is supported on the stroke disk 19 via the bearing disk 21. The slide shoe 20 is subjected to a static pressure reduction at the bearing disk 21. In order to supply the pressure medium to the pressure pocket arranged in the slide shoe 20, the slide shoe 20 and the drive mechanism piston 4 are provided with a plurality of longitudinal holes connected to the corresponding displacement chambers.

  The slide shoe 20 is tiltably attached to the drive mechanism piston 4 by a ball joint, and has a slide shoe neck 20a and a slide shoe plate 20b, as will be apparent in detail with reference to FIG. . An end surface of the slide shoe plate 20 b directed toward the bearing disk 21 forms a sliding surface for sliding the slide shoe 20 along the bearing disk 21. The opposite end surface of the slide shoe plate 20b facing the slide shoe neck 20a is formed as an annular slide shoe collar 20c. The slide shoe collar 20c cooperates with the disc-shaped retainer plate 30. The retainer plate 30 constitutes a holding device for the slide shoe 20 and prevents the slide shoe 20 from being lifted from the stroke disk 19 or the bearing disk 21.

  The retainer plate 30 according to the present invention rotates together with the cylinder block 2 and is formed as a disc spring-like spring element 31 as will become apparent in connection with FIG. The retainer plate 30 formed as a disc spring has a raised portion on the inner periphery. The raised portion has a spherical crown portion 32a on the inner peripheral surface. The cylinder block neck of the cylinder block 2 includes a spherical crown portion 32b on the outer peripheral surface. The retainer plate 30 is supported on the spherical crown portion 32b by a spherical crown portion 32a in a joint manner or tiltably.

  The conical retainer plate 30 formed as a disc spring has a predetermined inclination toward the cylinder block 2 as shown in detail in FIG.

  The spring-elastic retainer plate 30 has a conical disc segment 34. Each disk segment 34 is provided with a hole-like notch 35 for accommodating the slide shoe 20. Through this cutout 35, one slide shoe 20 protrudes at a slide shoe neck 20a. In the range of the hole-shaped notch 35, the retainer plate 30 is formed with a plurality of spring teeth 33 each directed inward. These spring teeth 33 are directed to the slide shoe plate 20b in the starting state, and cooperate with the slide shoe collar 20c provided on the slide shoe plate 20b of each slide shoe 20. A plurality of spring teeth 33 that are directed inward and inclined toward the slide shoe plate 20b of the slide shoe 20 are distributed and arranged in the corresponding notch 35 over the entire circumference of the corresponding notch 35. ing.

  In the axial piston machine 1 according to the present invention, the retainer plate 30 formed in a spring elasticity is in contact with the slide shoe plate 20b of the slide shoe 20 by the spring teeth 33 without play. Accordingly, the spring elastic retainer plate 30 holds the slide shoe 20 against the bearing disk 21 or the stroke disk 19 on the one hand and, on the other hand, via a joint-type connection to the cylinder block 2, A pressing force acting on the cylinder block 2 is generated. This pressing force presses the cylinder block 2 against the control surface 5 at the end face. In FIG. 1, the force transmission path KF of the retainer plate 30 formed in a spring-elastic manner is indicated by a broken line. The force transmission path KF presses the slide block 20 against the bearing disk 21 or the stroke disk 19 and simultaneously presses the cylinder block 2 against the control surface 5.

  The retainer plate 30 formed in a spring-elastic manner eliminates the need for an additional pressing spring that generates a pressing force acting on the retainer plate 30. Furthermore, the pressing of the cylinder block 2 against the control surface 5 achieved by the spring-elasticly formed retainer plate 30 causes an additional pressing spring, for example a drive shaft 15 and the cylinder block 2, between the cylinder block 2. In order to avoid tilting of the cylinder block 2 from the control surface 5 in the radial direction, a compression spring that holds the cylinder block 2 against the control surface 5 becomes unnecessary.

  The retainer plate 30 formed as a disc spring and having a plurality of spring teeth 33 in the range of the notches 35 shown in FIGS. 1 to 4 is lifted from the bearing disk 21 or the stroke disk 19. A characteristic curve of the spring force F and the pressing force of the slide shoe 20 with respect to the slide shoe movement amount S (refer to the arrow shown in FIG. 1), which forms a quantity, is obtained. This characteristic curve is shown in FIG.

  In the first characteristic line range B1, the retainer plate 30 has a gentle inclination of the characteristic line and thus the spring force F after the spring force and the holding force F are increased in the first characteristic line range B1 by the spring teeth 33 contacting the slide shoe collar 20c. And a characteristic line range K1 having a horizontal change region in the illustrated embodiment. In the characteristic line range K1, the assembly position of the axial piston machine 1 is given after the components are assembled.

  Immediately following the gently sloping characteristic line range K1, the spring-elastic retainer plate 30 has a characteristic line range B2 in which the spring force and thus the pressing force F increases rapidly. This characteristic line range B2 is defined as the conical disc segment of the spring elastic retainer plate 30 after the short lifting amount S defined from the bearing disc 21 or the stroke disc 19 and the slide shoe collar 20c of the slide shoe 20 is spring-elastic. This is achieved when applied to 34.

  The axial piston machine 1 according to the present invention is formed by the cylinder block 2, the drive mechanism piston 4, and the slide shoe 20 as shown on the right side of FIG. The rotated drive mechanism assembly can be formed as a pre-assembled assembly. The assembly as a whole can be incorporated into the housing 7 in which the stroke disk 19 is integrally formed. On the left side of FIG. 6, a corresponding prior art axial piston machine 1 is shown. The axial piston machine 1 includes a fixed pressing device for the slide shoe 20. In this fixed pressing device, the retainer plate 30a is fixed in the housing 7 in the axial direction by an additional holding ring 30b. In the known prior art axial piston machine 1, the cylinder block 2 is assembled into the housing 7 by fixing the retainer plate 30 a using the retaining ring 30 b in the housing 7 with the stroke disk 19. Time-consuming and time-consuming insertion of the drive mechanism piston 4 coupled to the slide shoe 20 into the notch 3 for the piston 2 is required.

  7 to 10 show a second embodiment of the axial piston machine 1 according to the present invention. The same symbols are attached to the same components.

  The axial piston machine 1 shown in FIGS. 7 to 10 has an adjustable displacement volume. For this purpose, the stroke disk 19 is formed in a swivel cradle 19a arranged in the housing 7 so as to be adjustable obliquely with respect to the rotation axis D.

  As shown in detail in FIG. 9, the disc-shaped retainer plate 30 formed in a spring elastic manner as shown in FIGS. 7 to 10 is formed as a disc spring having a slit.

  The retainer plate 30 formed as a disc spring-like spring element 31 shown in FIG. 9 has a raised portion on the inner periphery, similar to FIG. The raised portion has a spherical crown portion 32a on the inner peripheral surface. The retainer plate 30 is supported by the ball crown portion 32b of the cylinder block neck of the cylinder block 2 in a joint manner by the ball crown portion 32a.

  A spring-elasticly formed retainer plate 30 has a disk segment 34 with a plurality of spring tongues 36 directed radially outward to receive the slide shoe 20 adjacent to the raised portion. . Between the two spring tongues 36, one notch 37 having a long hole shape opened outward in the radial direction is formed. A slide shoe neck 20 a of one slide shoe 20 is accommodated in the notch 37. The spring tongue 36 that is directed radially outward is bent toward the slide shoe plate 20b of the slide shoe 20 in the starting state, as will become apparent in connection with FIG. And bent. Therefore, the spring tongue 36 cooperates with the slide shoe collar 20 c provided on the slide shoe plate 20 b of each slide shoe 20.

  In the axial piston machine 1 according to the present invention, the retainer plate 30 formed in a spring-elastic manner is in contact with the slide shoe collar 20c of the slide shoe 20 and the slide shoe plate 20b by the spring tongue 36 without play. Accordingly, the spring elastic retainer plate 30 holds the slide shoe 20 against the bearing disk 21 or the stroke disk 19 on the one hand and, on the other hand, via a joint-type connection to the cylinder block 2, A pressing force acting on the cylinder block 2 is generated. This pressing force presses the cylinder block 2 against the control surface 5 at the end face.

  Due to the spring-elastic retainer plate 30, there is no need or need for an additional pressing spring that generates a pressing force acting on the retainer plate 30. Furthermore, the pressing of the cylinder block 2 against the control surface 5 achieved by the spring-elasticly formed retainer plate 30 causes an additional pressing spring, for example a drive shaft 15 and the cylinder block 2, between the cylinder block 2. In order to avoid tilting of the cylinder block 2 from the control surface 5 in the radial direction, a compression spring that holds the cylinder block 2 against the control surface 5 becomes unnecessary. Therefore, the tooth row 18 between the cylinder block 2 and the drive shaft 15 can be formed without interruption and without omission of teeth as shown in FIG. Further, in the cylinder block 2 of the axial piston machine 1 according to the present invention, an addition for accommodating a pin in the range of the tooth row 18 as in the known prior art axial piston machine provided with a spring elastic pressing device. No weakening holes are required. Naturally, the configuration of the tooth row 18 shown in FIG. 8 is also possible in the axial piston machine 1 according to the present invention shown in FIGS.

  The retainer plate 30 formed as a disc spring having a slit shown in FIGS. 7 to 9 is a spring force related to the slide shoe movement amount S that forms the lift amount of the slide shoe 20 from the bearing disk 21 or the stroke disk 19. It has a characteristic curve of F. This characteristic curve is shown in FIG.

  In the first characteristic line range B1, the retainer plate 30 is loosened in the characteristic line and the spring force F after the spring force and thus the pressing force F is increased by the spring tongue 36 that contacts the slide shoe collar 20c of the slide shoe 20. It has a characteristic line range K1 having a change region of inclination, a change region slightly curved in a parabolic shape in the illustrated embodiment. This characteristic line range K1 forms an assembly position of the axial piston machine 1 after the components are assembled.

  Immediately following the characteristic line range K1 with a gentle slope, the retainer plate 30 has a characteristic line range B2 in which the spring force and thus the pressing force F increases rapidly. This characteristic line range B2 indicates that after a specified short lifting amount A from the bearing disk 21 or the stroke disk 19, the slide shoe collar 20c of the slide shoe 20 is adjacent to the raised portion of the spring elastic retainer plate 30. This is achieved when applied to the disk segment 34 formed in this manner. The lift amount A is shown in FIG. In FIG. 7, the slide shoe 20 is in contact with the spring tongue 36 of the retainer plate 30 only at the slide shoe collar 20c in the assembled position after the components are assembled, and the radius of the slide shoe collar 20c and the retainer plate 30 is increased. It is clear that there is an axial spacing A between the directional inner disk segment 34. Accordingly, when the slide shoe 20 is lifted from the bearing disk 21 or the stroke disk 19 by the axial distance A during operation of the axial piston machine 1, the slide shoe 20 is applied to the disk segment 34 by the slide shoe collar 20c. This achieves a steeply increasing force in the characteristic line range B2 of the spring characteristic line.

  FIG. 11 shows an improved form of the axial piston machine 1 according to the present invention. This refinement is in addition to the spring-elastic retainer plate 30 that already allows the basic pressing of the cylinder block 2 against the control surface 5, and an additional pressing spring 40 that presses the cylinder block 2 against the control surface 5. It has. The pressing spring 40 is formed as a compression spring disposed in the radial direction between the drive shaft 15 and the cylinder block 2. On the first side, the pressing spring 40 is supported on the drive shaft 15 of the axial piston machine 1 by a contact ring 41, for example, a contact ring that contacts the shaft step portion of the drive shaft 15, and on the second side. The contact ring 42 attached to the cylinder block 2 is supported by the cylinder block 2 by, for example, a position fixing ring inserted into an annular groove provided on the inner peripheral surface of the cylinder block 2.

  The axial piston machine 1 according to the invention with a retainer plate 30 formed as a disc spring and thus formed in a spring-elastic manner has a series of advantages.

  The retainer plate 30 in the present invention forms a holding device without play of the slide shoe 20, and has a characteristic line range K1 of a gentle inclination to which an assembly position after assembly of the axial piston machine 1 is given. Due to the course of the line, the retainer plate 30 for the slide shoe 20 formed by the spacing error, in particular, the mounting surface of the retainer plate 30 for the cylinder block 2 and the spring teeth 33 or the spring tongue 36 formed by the spherical crown portion 32a. Enables automatic compensation for the distance error between the mounting plate and the component error of the retainer plate 30 itself.

  When the slide shoe 20 is lifted from the bearing disk 21 or the stroke disk 19, a high pressing force F is generated by the characteristic line range B2 in which the spring force of the retainer plate 30 and the pressing force F in the present invention rapidly increases. Be made. As a result, the lift amount of the slide shoe 20 is limited, and the risk of damage to the slide shoe 20 and the stroke disk 19 or the bearing disk 21 is reduced. The increased pressing force F can be generated only when the slide shoe 20 is lifted from the bearing disk 21 or the stroke disk 19 by the spring elastic retainer plate 30 in the present invention. During normal operation, the friction between the slide shoe 20 and the bearing disk 21 is reduced, so that the slide shoe 20 has little wear and the loss output of the axial piston machine 1 according to the present invention is small. Become.

  The basic pressing force of the cylinder block 2 to the control surface 5 is driven with the cylinder block 2 by simultaneously transmitting the pressing force F of the slide shoe 20 to the cylinder block 2 by the spring elastic retainer plate 30 in the present invention. Without additional pressing springs between the shafts 15, it can thus be achieved by structurally simple means. By omitting the pressing spring for the cylinder block 2, the structure of the axial piston machine 1 according to the present invention is simplified, and the tooth row 18 between the cylinder block 2 and the drive shaft 15 can be extended.

  Compared to known prior art fixed pressing devices, the pressing device according to the present invention eliminates the holding ring or holding plate for fixing the retainer plate 30 in the housing 7 in the axial direction, and for the holding ring or holding plate. Omission of mechanical processing of the contact surface simplifies the construction and production of the housing 7.

  Furthermore, in the axial piston machine 1 according to the present invention, a simple and compact assembly of the pre-assembled drive mechanism assembly in the enclosing housing 7 is achieved within the housing 7 with the stroke disk 19. This is possible without troublesome and time-consuming insertion of the drive mechanism piston 4 into the piston notch 3 of the cylinder block 2.

  The spring force of the compression spring pressing the cylinder block against the control surface is transmitted to the retainer plate by means of a pin provided in the region of the tooth row between the cylinder block and the drive shaft, and is formed elastically in the known prior art. Compared to the pressing device, the spring elastic retainer plate 30 according to the present invention avoids weakening of the tooth row 18 between the drive shaft 15 and the cylinder block 2 and weakening of the cylinder block 2 in the range of the cylinder block neck. The

  According to FIG. 11, further advantages are obtained as long as the spring-elastic retainer plate 30 according to the invention is combined with an additional pressing spring 40 for pressing the cylinder block 2 against the control surface 5. The pressing force generated by the spring elastic retainer plate 30 of the slide shoe 20 is independent of the pressing force of the pressing spring 40 of the cylinder block 2 as compared to the known spring elastic pressing device of the prior art. Can be formed. Thereby, the friction between the slide shoe 20 and the bearing disk 21 or the stroke disk 19 can be reduced. Since the spring elastic retainer plate 30 in the present invention supports the reaction force of the pressing force of the slide shoe 20 in the cylinder block 2, the spring elastic retainer plate 30 moves the cylinder block 2 to the control surface 5. The pressing force is also strengthened. Therefore, the pressing force of the cylinder block 2 against the control surface 5 is formed by the force of the spring elastic retainer plate 30 and the force of the pressing spring 40 of the cylinder block 2, so that the axial piston machine 1 according to the present invention is used. Then, when the pressing force for the cylinder block 2 is required, the pressing spring 40 can be reduced as compared with a known prior art axial piston machine. The configuration space between the cylinder block 2 and the drive shaft 15 obtained by the reduction of the pressing spring 40 extends the tooth row 18 between the cylinder block 2 and the drive shaft 15 in the axial piston machine 1 according to the present invention. Can be used to

  The present invention is not limited to the illustrated embodiment. Naturally, FIGS. 1 to 4 and FIGS. 7 to 7 formed as a disc spring-like spring element 31 in order to obtain a desired characteristic curve course with a section of gentle slope and a range with a sudden force increase. It is possible to adapt the spring characteristic line of the retainer plate 30 shown in FIG. Further, the characteristic line course shown in FIG. 10 is set in the retainer plate 30 shown in FIGS. 1 to 4, and the characteristic line course shown in FIG. 5 is set in the retainer plate 30 shown in FIGS. Is also possible.

DESCRIPTION OF SYMBOLS 1 Axial piston machine 2 Cylinder block 3 Piston notch 4 Drive mechanism piston 5 Control surface 6 Bottom control member 7 Housing 7a Housing cover 8 Inflow port 9 Outflow port 10 Connection passage 15 Drive shaft 16 Bearing 17 Bearing 18 Teeth row 19 Stroke disc 19a Swivel cradle 20 Slide shoe 20a Slide shoe neck 20b Slide shoe plate 20c Slide shoe collar 21 Bearing disc 30, 30a Retainer plate 30b Holding ring 31 Spring element 32a Ball crown 32b Ball crown 33 Spring tooth 34 Disc segment 35 Cutting Notch 36 Spring tongue 37 Notch 40 Pressing spring 41 Contact ring 42 Contact ring A Lifting amount B1 Characteristic line range B2 Characteristic line range D Rotating axis F Spring force K1 Characteristic line range KF Force transmission path S Slide shoe travel

Claims (12)

  An axial piston machine (1) having a swash plate structure, wherein the axial piston machine (1) includes a cylinder block (2) disposed so as to be rotatable about a rotation axis (D). (2) includes at least one piston notch (3), and each drive mechanism piston (4) is slidably disposed in the longitudinal direction in the piston notch (3). The drive mechanism piston (4) is supported on the stroke disk (19) by one slide shoe (20), and is rotationally synchronized with the cylinder block (2) operatively coupled to the slide shoe (20). The retainer plate (30) is provided so that the slide plate (2) can be connected to the stroke disc (19). In an axial piston machine with a swash plate structure that protects against the lifting of the plate, the retainer plate (30) is formed as a disc spring-like spring element (31), and the spring element (31) It is supported by the cylinder block (2) on the inner peripheral surface in a joint manner, and an additional pressing spring for generating a pressing force acting on the retainer plate (30) is not provided at that time. Axial piston machine with swash plate structure.   The retainer plate (30) is provided with a spherical crown (32a) on the inner peripheral surface for joint support to the cylinder block (2), and the spherical crown (32a) is connected to the cylinder block (2). The axial piston machine according to claim 1, wherein the axial piston machine is supported by a cylinder block neck (32 b) having a spherical shape provided on a spherical crown.   3. An axial piston machine according to claim 1, wherein the retainer plate (30) is in contact with the slide shoe (20) without play.   The spring characteristic line of the retainer plate (30) has a characteristic line range (K1) with a region of change of the gentle slope of the spring characteristic line, and the characteristic line range (K1) is the axial piston machine (1 4) enables automatic error compensation of the retainer plate (30), the cylinder block (2), and the slide shoe (20) at the assembly position after assembly). An axial piston machine according to claim 1.   The retainer plate (30) is provided with a hole-like notch (35) for accommodating the slide shoe neck (20a) of each slide shoe (20), and the retainer is within the range of the notch (35). 5. The plate according to claim 1, wherein the plate (30) has a plurality of spring teeth (33) directed inward and directed to the slide shoe plate (20b) of the slide shoe (20). An axial piston machine according to claim 1.   5. The axial piston machine according to claim 1, wherein the retainer plate (30) is formed as a disc spring with a slit.   The retainer plate (30) includes a plurality of spring tongues (36) oriented radially outward, and one slide shoe (20) slide shoe between each of the two spring tongues (36). 7. An axial piston machine according to claim 6, wherein a notch (37) is formed for receiving the neck (20a).   The retainer plate (30) has a characteristic line range (B2) with a sudden increase region of the spring force immediately following the characteristic line range (K1) with a change region of the gentle inclination of the spring characteristic line. An axial piston machine according to any one of claims 1 to 7.   The retainer plate (30) is a retainer plate (30) which is a slide shoe plate (20b) after a prescribed lifting amount (A) of the slide shoe (20) from the stroke disc (19). 9. An axial piston machine according to claim 1, wherein the axial piston machine is adapted to be applied to a disk segment (34).   The cylinder block (2), the slide shoe (20), and the retainer plate (30) are formed as a pre-assembled drive mechanism assembly that can be assembled in the housing (7) of the axial piston machine (1). An axial piston machine according to any one of the preceding claims.   11. An axial piston machine according to any one of claims 1 to 10, wherein an additional pressing spring (40) is provided for generating a pressing force for pressing the cylinder block (2) against the control surface (5).   The pressing spring (40) is supported on the drive shaft (15) of the axial piston machine (1) on the first side and supported on the cylinder block (2) on the second side. Axial piston machine.

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