Radial support axle valve distributing cycloid hydraulic motor
The present invention relates to a kind ofly realize that through cycloidal-pin wheel group engagement pair hydraulic pressure can be to the cycloid hydraulic motor of mechanical energy conversion, especially a kind of bearing radial force axle valve distributing cycloid hydraulic motor with two bearings belongs to hydraulic transmission technology field.
Cycloid hydraulic motor is a fluid pressure drive device commonly used, also is to realize that hydraulic pressure can convert the hydraulic pressure execution device commonly used of function to.Cycloid hydraulic motor has advantages such as volume is little, specific power density is big, efficient is high, speed range is wide, thereby has obtained extensive use.
The basic structure of this type of device is to be shaped on liquid entering hole and refluxing opening on body shell or the bonnet; One end is equipped with cycloidal pinion engaged pair and flow-distribution mechanism; Flow-distribution mechanism can be placed on before or after the cycloidal pinion engaged pair; Being axle valve flow in preceding (body shell one side) generally, is the plane flow in back (bonnet one side), and the other end is equipped with output shaft.The rotor of cycloidal pinion engaged pair is through the external gear engagement of internal spline and couple axle one end, and the other end of couple axle is connected with the output shaft transmission.During work, flow-distribution mechanism is communicated with the secondary expansion engagement chamber of liquid entering hole and cycloidal-pin wheel, and the secondary contraction chamber of cycloidal-pin wheel is communicated with refluxing opening.As a result, after pressured fluid gets into body shell or bonnet from liquid entering hole, get into the expansion engagement chamber that cycloidal pinion engaged pair forms, its volume is constantly enlarged, liquid then refluxes from refluxing opening in the contraction engagement chamber that the while cycloidal pinion engaged pair forms; In this process, the rotor of cycloidal pinion engaged pair is expanded the engagement chamber and orders about rotation with the pressure difference of shrinking the engagement chamber, and this rotation is delivered to output shaft output through couple axle, thereby realizes that hydraulic pressure can be to the conversion of mechanical energy.Meanwhile, also by the couple axle driven rotary, the continuous switching connected state that goes round and begins again makes transfer process be able to continue to flow-distribution mechanism (axle valve).Like this, the output torque that motor just can be continuous.
Understand according to the claimant; The conventional construction that the Bearing Installation diameter of axle of the existing said structure of CN200820035921.1 separates with the flow diameter of axle; Its separation structure can solve the independently high-precision processing size requirement and the status requirement of the flow diameter of axle and the Bearing Installation diameter of axle; Rely on the structure of locating stud to solve the high-precision requirement of the flow diameter of axle and the assembling of the Bearing Installation diameter of axle, but the processing of locating stud and assembly precision can influence the flow precision problem again conversely.
Cycloid hydraulic motor with axle valve flow that bearing structure supports is using scope more and more widely (BM2, the BM3 product produced like the claimant) at home; The operating mode of using also more and more widely; The requirement of using is also increasingly high, the motor that market demand is more superior.Along with the raising of process equipment precision, can innovate again existing motor configuration, further improve the flow precision of motor.
Summary of the invention
The objective of the invention is to: to the problem of above existing technology existence; Propose a kind of compact structure and can bear the axle valve distributing cycloid hydraulic motor of big radial force; And reduce the axle of axle valve flow motor and the complex structure degree in hole; Make the manufacturability of processing, assembling of oil hydraulic motor all good, improve its cost performance.
In order to achieve the above object; The claimant is through the structural analysis to discharge capacity 160-630 milliliter/medium-sized discharge capacity cycloid hydraulic motor bigger than normal of commentaries on classics; Especially has a research of valve distributing construction cycloid tooth wheel set oil hydraulic motor integral structure layout; Find out the weak link of its bearing radial force, keeping under the constant prerequisite of existing whole motor (BM2, the BM3 that produce like the claimant) profile installation dimension, technological scheme of the present invention below the proposition is: a kind of valve distributing cycloid hydraulic motor; One end is the body shell that is shaped on liquid entering hole and refluxing opening, the cycloidal-pin wheel pair of the other end for mainly being made up of stator and rotor; Said body shell one end is equipped with the output shaft that the outer end extends out, the middle part be equipped with two ends respectively with the couple axle of said output shaft the inner and rotor internal spline engagement; Its improvements are: the front end of said output shaft is installed the bearing radial force bearing; Said bearing is two single-groove grooved ball bearings; Bearing outer ring one end is resisted against on the protecgulum; The other end is resisted against on the step hole of housing, and bearing inner race one end is resisted against on the output shaft shaft shoulder, and the other end is fixed by shaft block ring.
The mounting hole of described bearing outer ring and housing adopts a kind of cooperating of pine, and transition fit is adopted in described cooperation, from magnitude of interference 0.01mm to the gap 0.015mm.
Bearing Installation one end of described output shaft and the flow diameter of axle of output shaft are one, and the matching gap in the aperture of the diameter of axle of output shaft and body shell is controlled at 0.012mm ~ 0.026mm.
Above technological scheme is further improved: two-part have a tiny annular groove at least before and after the flow-distribution mechanism circular groove of output shaft.
Further perfect of above technological scheme is: described protecgulum is step-like, and the interior step of bearing abutment facing has been installed the skeleton rotary shaft sealing, and the other end of bearing abutment facing is equipped with the skeleton dust ring; The outside of bearing abutment facing is step-like for outward; Outer step is consistent with the bearing outer ring nominal size, and the housing bore that both match is the same, helps processing; Has an annular groove on the outer step; The inner seal ring of installing of annular groove seals, and the gap control of outer step and bearing outer ring mounting hole is between 0.05mm ~ 0.12mm, and the best is 0.08mm.
Compare with the gerotor motor of existing technology; Motor can bear big radial force after the above-mentioned improvement structure of the present invention; Simultaneously also can bear certain axial force, and processing, assembling are all very convenient, can enlarge the application area of motor; Its structure helps reducing the extra feel trim actuator of client, practices thrift cost.
Description of drawings
Below in conjunction with accompanying drawing the present invention is described in further detail.
Fig. 1 is the structural representation of one embodiment of the invention one.
Dust ring 1 among the figure, axle envelope 2, and screw 3, O type circle 4, bearing 5, the body shell, 6, hydraulic fluid port lid 7, O type circle 12 is at a distance from dish 13, stator 14, rotor 15, pin tooth 16, bonnet 17, plug screw 18, rivet 19, label 20, bolt 21, output shaft 22, couple axle 23, back-up ring 24, protecgulum 25.
Fig. 2 is the structural representation of output shaft 22 among Fig. 1 embodiment one.
Fig. 3 is the local enlarged diagram of output shaft 22 among Fig. 1 embodiment one.
Fig. 4 is the structural representation of one embodiment of the invention two.
Dust ring 1 among the figure, axle envelope 2, screw 3, O type circle 4, bearing 5, body shell, 6; Hydraulic fluid port lid 7, elastomer 8, valve ball 9, valve body 10, seal ring 11, O type circle 12 is at a distance from dish 13; Stator 14, rotor 15, pin tooth 16, bonnet 17, plug screw 18, rivet 19; Label 20, bolt 21, output shaft 22, couple axle 23, back-up ring 24, protecgulum 25.
Fig. 5 is the structural representations of the separated dish 13 of the embodiment of the invention two towards body shell 6 one sides.
The bearings axle valve distributing cycloid hydraulic motor of present embodiment can bear big radial force; And certain axial force; Motor configuration is bigger, discharge capacity 160-630 milliliter/commentaries on classics, and basic structure is as shown in Figure 1; Mainly comprise output shaft 22, protecgulum 25, body shell 6, couple axle 23, separated dish 13, change stator pinwheel pair 14,15 and 16, bonnet 17 etc.; Wherein cycloidal pinion engaged pair is made up of rotor, stator and pin tooth, stator 14 be fixed on jointly on the body shell 6 by bolt 21 at a distance from dish 13 and bonnet 17, thereby form seven only in the consubstantiality shell 6 flow duct, the cavity that communicates one by one at a distance from the high low pressure oil through of dish 13.
Described bearings axle valve distributing cycloid hydraulic motor, an end is the body shell 6 that is shaped on liquid entering hole and refluxing opening, the cycloidal-pin wheel pair of the other end for mainly being made up of stator 14 and rotor 15 and pin tooth 16; Said body shell 6 one ends are equipped with the output shaft 22 that the outer end extends out, the middle part be equipped with two ends respectively with the couple axle 23 of said output shaft 22 the inners and rotor 15 internal splines engagement; Its improvements are: the front end of said output shaft 22 is installed the bearing radial force bearing; Said bearing is two single-groove grooved ball bearings 5; Bearing outer ring one end is resisted against on the protecgulum; The other end is resisted against on the step hole of housing, and bearing inner race one end is resisted against on the output shaft shaft shoulder, and the other end is fixing by shaft block ring 24.
Described bearing radial force bearing 5 also can be selfaligning bearing, is bearing under a little little radial force working condition.
The mounting hole of described bearing 5 outer rings and housing 6 adopts a kind of cooperating of pine, and transition fit is adopted in described cooperation, from magnitude of interference 0.01mm to the gap 0.015mm.Adopt the described cooperation of pine; Mainly be the needs of relative movement of formation oil film of a valve of the flow-distribution mechanism that forms of the aperture for the diameter of axle of the output shaft 22 that is fit to bearings axle valve distributing cycloid hydraulic motor and body shell 6; The aperture motion of the diameter of axle of described output shaft 22 and body shell 6 forms the function of similar sliding bearing; Can bear certain radial force, the matching gap in the aperture of the diameter of axle of output shaft 22 and body shell 6 is controlled at 0.012mm ~ 0.026mm, under higher motion speed, selects big value; Select little value under than harmonic motion speed, described bearing 5 cooperation of pine be make output shaft 22 at work the oil film of flow-distribution mechanism need to form.
Be shaped on distributing construction on the output shaft 22; With in the body shell 6 the flow duct cooperate jointly and have a flow function; Processed 12 cannelure and two circular grooves that are uniformly distributed with dislocation on this device, described cannelure becomes staggered links up with two circular grooves, and two circular grooves communicate respectively with into and out of hydraulic fluid port; Processed on the body shell 6 duct with high low pressure fluid and the flow duct; The radially direct hole in cannelure and the flow duct of body shell 6 or groove be flow mutually, and described cannelure is to be defined by a radius, and is processed by the direct feed of milling cutter.Output shaft 22 has been formed flow-distribution mechanism with the body shell 6 common axle valves that form and has been realized keeping the flow function of oil hydraulic motor continuous running.
Output shaft 22 basic structures are as shown in Figure 2; The endoporus that output shaft 22 front ends are meshed with couple axle 23 has an aperture and logical near the mounting groove trough box drain of shaft block ring 24; Major part is in groove, and when shaft block ring 24 was installed, open part was over against aperture; Help motor and form inner fluid circulation, the front sealing band that also helps flow-distribution mechanism increases.The internal spline that is meshed with couple axle 23 of described output shaft 22 adopts cold-extrusion technology to process, and the terminal surface of internal spline be conical, is 6 to spend to 10 and spend with the radial alignment angle [alpha].
The local basic structure of amplifying of the I of output shaft 22 is as shown in Figure 3; Two-part have a tiny annular groove at least before and after the circular groove of the flow-distribution mechanism of output shaft 22, since the existence of the matching gap in the aperture of the diameter of axle of output shaft 22 and body shell 6, the infiltration of high-voltage oil liquid; Form the motion oil film; Described annular groove helps the formation and the existence of oil film, and motion annular groove high-voltage oil liquid is assembled, and further reduces the leakage that produces owing to the gap.Described annular groove is a circular arc, highly is not more than 0.5mm, and described annular groove also can be a square groove shape, highly is not more than 1mm.
The mounting hole of said bearing 5 outer rings and housing 6 increase by a step surface against end face; Step surface minimum clearance is 0.3mm; Prevent to contact with inner ring; The installation shaft shoulder of bearing 5 inner rings and output shaft 22 increase by a step surface against end face, step surface minimum clearance is 0.3mm, prevents to contact with the outer ring.
The protecgulum 25 of said output shaft front end is step-like, and the interior step of bearing 5 abutment facings has been installed skeleton rotary shaft sealing 2, and the other end of bearing 5 abutment facings is equipped with skeleton dust ring 2; The outside of bearing 5 abutment facings is step-like for outward; Outer step is consistent with bearing 5 outer ring nominal sizes, about the big 0.03mm in housing bore aperture that the former matches, helps the bearing assembling; Can not damage sealing surface during installation; Have an annular groove on the outer step of described protecgulum 25, the inner seal ring of installing of annular groove seals, and described seal ring can be O type circle 4; The gap control of the outer step diameter of axle of described protecgulum and bearing outer ring mounting hole is between 0.05mm ~ 0.12mm, and the best is 0.08mm.
The foregoing description skeleton rotary shaft sealing 2 adopts high pressure shaft seal, directly bears high back pressure; Also can adopt the common cycloid oil hydraulic motor with the axle envelope, for protecting directly fuel tank of the outer drain tap of rotary shaft sealing.
Embodiment two basic structure is as shown in Figure 4; Be shaped on the drainback passage that is communicated with the motor internal cavity on the body shell 6, described drainback passage is a loop structure, and two one-way valves are installed in the described passage; Two one-way valve one ends link to each other with return opening with filler opening respectively; The other end is communicated with the motor internal cavity through internal drainage liquid one-way valve return opening passage 03,04 on dish 13 respectively, and is as shown in Figure 5 towards the one side of body shell 6 at a distance from dish 13, and described internal drainage liquid one-way valve return opening passage 03,04 on dish 13 is radially direct; The position is corresponding with the one-way valve hole site on the body shell 6; Circular arc that return opening passage 03,04 is formed by Milling Process and tangent linear structure, tangent straight line becomes less than 10 degree angles towards changeing the stator direction, helps oil return.One-way valve is made up of elastomer 8, valve ball 9, valve body 10, seal ring 11.10 one-tenth steps of valve body are poroid, are installed in the body shell 6 through seal ring 11.In the big end of step hole valve ball 9 is housed; The outside of this valve ball is resisted against on the elastomer 8, and seal ring 11 can be an O type circle, also can be the Glais ring structure that the outer fluoridize circle of O type circle is formed; Because interior engagement cycloidal pinion engaged pair is under the driving of high low pressure hydraulic oil; When producing moment of torsion, need certain clearance for guaranteeing to rotate flexibly between its each revolute pair, have a spot of oil liquid leakage unavoidably and get into the motor internal cavity; And then get back in system's fuel tank through one-way valve, perhaps the outer drain tap T through plug screw 18 positions gets back in system's fuel tank.
Present embodiment has adopted two one-way valves to communicate with oil inlet and outlet, helps protecting rotary shaft sealing.
Facts have proved that the Coefficient of discharge of bearings axle valve distributing cycloid hydraulic motor of the present invention is less, the parts machining process moderate accuracy; The good manufacturability of assembling, reliability is high, and compact structure; Big radial force be can bear, thereby cost performance of product and applying working condition improved.The locating stud that has solved the conventional construction that the Bearing Installation diameter of axle of US3547563, the said structure of CN200820035921.1 separates with the flow diameter of axle influences the flow precision problem; Structure of the present invention and Rational Parameters select to solve traditional design does not adopt increases bearing on the integrated type output shaft design concept, the roughly the same existing product of the machining accuracy in other the diameter of axle and hole.
Except that the foregoing description, the present invention can also have other mode of executions.For example, adopt the diameter of axle of different bearings to adapt to the rotary shaft sealing of the different diameters of axle, or the output shaft front end have the position adjustment or the like of an aperture of the endoporus that is meshed with couple axle.All employings are equal to the technological scheme of replacement or equivalent transformation formation, all drop on the protection domain of requirement of the present invention.