Bent axle is many fulcrums crank mechanism of combined type crank pin structure
Technical field
The utility model relates to a kind of crank mechanism of bent axle transmission, and especially a kind of architecture advances that realizes rotating between prime mover and the actuator bent axle driving crank mechanism that transforms mutually with straight reciprocating motion belongs to the mechanical transmissioning technology field.
Background technique
The typical structure of common crank mechanism mainly is made of bent axle, connecting rod and slide block (crosshead or piston) as shown in Figure 1.In crank mechanism, the effect of bent axle (or claim crankshaft, crank shaft) is that the conversion of motion with prime mover becomes one of vitals of the required forms of motion of actuator.During work, bent axle bears periodically alternate load.Traditional crank mechanism has two quasi-representative structures: 1. take solid forging (casting) when making when bent axle, as shown in Figure 2, the supporting axle position of the cranking arm of bent axle, crank pin and bent axle is an integral body.Be subjected to structural limitations, connecting rod tip must adopt the middle open type structure in this mechanism, be that connecting rod tip is made up of connecting rod cap, connecting rod shank, and link into an integrated entity with two connecting-rod bolts, connecting rod tip and crank are connected and can only adopt split bushing supporting (referring to Fig. 4), thereby the relative movement of connecting rod and crank pin can only be to slide, so the lubricating requirement of kinematic pair is higher.In entire mechanism, need independently lubrication system that it is carried out pressure lubrication sometimes, and the connecting rod manufacturing process complexity of split type structure, simultaneously because the split type structure of connecting rod tip makes the integral rigidity of connecting rod be affected.For many crank throws (crank mechanism of multi-joint forms of motion) integral one-piece crankshaft, manufacturing process such as the processing of its crank pin, heat treatment, grinding are more complicated.Because structural limitations, bent axle can only be supported by bearings at both ends, makes that the bearing stride of bent axle is big, easily produces deflection deformation, is unfavorable for bearing bigger moment of flexure (i.e. the piston force that is directly transmitted by connecting rod).2. when bent axle in the system adopts eccentric shaft structure (referring to Fig. 3), though can avoid unfavorable factor to a certain extent because of the crank pin processing difficulties of crank shaft, and connecting rod tip needn't adopt middle open type when crank pin is reduced to eccentric wheel structure, the bearing of rolling bearing as connecting rod tip promptly is installed on eccentric wheel disc, can simplify the technological requirement of the processing and the assembling of connecting rod like this, but for the crank mechanism of multi-joint forms of motion, because structural limitations, bent axle as eccentric shaft structure in the crank mechanism can only adopt the big bearings at both ends supporting of span, exist system rigidity poor equally, the drawback that is unfavorable for bearing bigger moment of flexure (piston force).
Retrieval finds, application number is that 03136914.6 Chinese patent application discloses the bent axle that is used for large-sized two-stroke cross-head internal combustion engine, comprises many crank throws.Each crank throw all is made up of two crankwebs that linked together by crank pin.Crank throw is intactly interconnected by many main journals.Application number is that 02294651.9 Chinese patent application has openly been opened segmentation eccentric shaft type plunger pump bent axle, parallel equidistant eccentric bushing and several band gear eccentric bushing that is crisscross arranged in cylinder body, main shaft runs through the endoporus of eccentric bushing and band gear eccentric bushing, eccentric bushing and band gear eccentric bushing parallel equidistant are crisscross arranged on main shaft, with flat key fixedly eccentric bushing and band gear eccentric bushing, an end of main shaft fixedly installs main shaft bearing.In addition, application number is the detachable combined crank that 200510023854.2 Chinese patent application discloses a kind of field of textile machinery, it is characterized in that it comprises L type fluting crankshaft section with holes, socket head screw and Z type crankshaft section.
Above patent application has been carried out useful improvement to the bent axle of traditional crank mechanism respectively, but all can only not adopt the drawback of the big bearings at both ends supporting of span at bent axle, therefore still has the problem that system rigidity is poor, be unfavorable for bearing big moment of flexure.
The model utility content
The utility model wants the technical solution problem to be: at drawback or problem that above prior art exists, proposing a kind of bent axle is many fulcrums crank mechanism of combined type crank pin structure, thereby obtains the ideal system rigidity, can bear big moment of flexure.
In order to solve above technical problem, bent axle of the present utility model is that many fulcrums crank mechanism basic technical scheme of combined type crank pin structure is: comprise body, being shaped on the disjunctor that at least three places get out of the way connecting rod position on the described body supports, described disjunctor supports and is shaped on concentric pylone, support the coaxial bent axle of rotatable segmentation in described each through hole respectively, the opposite end of described adjacent sectional bent axle is shaped on corresponding eccentric structure respectively, described corresponding eccentric structure supports the two end part of crank pin respectively, the cylindrical of described crank pin interts in the endoporus of connecting rod one end, and at least one place forms revolute pair between described eccentric structure and the crank pin and between the endoporus of the cylindrical of described crank pin and connecting rod one end.
According to above basic technical scheme of the present utility model, it is as follows that several typical cases that those skilled in the art understand easily implement structure:
1), the opposite end of described adjacent sectional bent axle is shaped on corresponding eccentric opening respectively, described corresponding eccentric opening supports the two ends of crank pin respectively; The cylindrical of described crank pin interts in the endoporus of connecting rod one end, and forms revolute pair.
2), the opposite end of described adjacent sectional bent axle is shaped on corresponding eccentric shaft respectively, described corresponding eccentric shaft supports the two ends center hole of crank pin respectively; The cylindrical of described crank pin interts in the endoporus of connecting rod one end, and forms revolute pair.
3), the opposite end of described adjacent sectional bent axle is shaped on corresponding eccentric opening respectively, described corresponding eccentric opening supports the two ends of crank pin respectively, and forms revolute pair; The cylindrical of described crank pin interts in the endoporus of connecting rod one end.
4), the opposite end of described adjacent sectional bent axle is shaped on corresponding eccentric shaft respectively, described corresponding eccentric shaft supports the two ends center hole of crank pin respectively, and forms revolute pair; The cylindrical of described crank pin interts in the endoporus of connecting rod one end.
Outstanding advantage of the present utility model is as follows:
1, because bent axle by multi-point support, is therefore compared with the two-end-point supporting structure of the big span of tradition, rigidity and intensity strengthen greatly, help bearing bigger moment of flexure.
2, the manufacturing of each component is very simple, and thermal treatment quality is controlled easily, has abandoned the complicated processing technology of traditional integral formula bent axle.
3, easy disassembling allows to rotate vice division chief and adopts rolling bearing, and is lubricated convenient, helps improving the transmission performance of crank mechanism.
Description of drawings
Below in conjunction with accompanying drawing the utility model is further described.
Fig. 1: existing typical crankshaft driving crank linkage mechanism structural representation.
Fig. 2: the schematic representation of existing crank pin structure bent axle.
Fig. 3: the schematic representation of existing eccentric shaft structure bent axle.
Fig. 4: the schematic representation of existing middle open type connecting rod tip structure.
Fig. 5: the structural representation of the utility model preferred embodiment.
Fig. 6: the application structure schematic representation of the utility model preferred embodiment.
The sectional view of Fig. 7: Fig. 6.
Embodiment
Embodiment one
Present embodiment is many fulcrums crank mechanism of the box-like crank pin structure of preferred group, as shown in Figure 5, specifically be the horizontal single-acting reciprocating pump of three cylinder horizontal arrangement that is applied in a kind of electric reciprocating plunger pump, its main structure is by being made up of power end and fluid end two-part, as Fig. 6, shown in Figure 7.The main member of power end has: eccentric shaft structure multi-point support assembled crankshaft assembly, connecting rod 06, crosshead 16 and be contained in crank bore and crank pin between selfaligning roller bearing 07.
Particularly, the supporting section of bent axle is made up of coaxial bent axle spindle nose section 12, intermediate section 13 and latter end 15, and they are bearing in the respective through hole with the supporting structure of body 02 disjunctor by axle head block bearing 09 and center support bearing 05 respectively.The two ends of crank pin 14 are respectively charged in the corresponding eccentric opening that bent axle intermediate section 13, bent axle spindle nose section 12 or bent axle latter end 15 end faces make, and form fixed bearing.Connecting rod tip 06 is assemblied in by connecting rod tip selfaligning roller bearing 07 on the cylindrical of crank pin 14, and the both ends of the surface of connecting rod tip selfaligning roller bearing 07 inner ring respectively are equipped with a spacer ring 08, so that the connecting rod tip axially locating.
The segmentation bent axle at two ends is shaped on the inside shaft shoulder respectively, end cap 11 that is connected with body 02 and tail-hood 01 seam end face and the selfaligning roller bearing by separately respectively are resisted against on the shaft shoulder of corresponding segmentation bent axle, formation is equipped with the spacer ring 08 that is enclosed within on the crank pin to the circumferential position constraint of segmentation bent axle between each segmentation bent axle.Bent axle latter end 15 outer end fixed pin shaft footstocks 03 are equipped with the Cock screw 04 of the crank pin axle head that leans herein on this bearing pin footstock 03, the opposing end surface of each adjacent crankpin axle mutually against.Therefore, the axial positioning structure of crankshaft group on body 02 that the segmentation bent axle constitutes is: the seam end face of end cap 11 (bearing support 10 places) or tail-hood 01 gives assembling and tightly tries hard to recommend to axle head block bearing selfaligning roller bearing outer ring, make bearing press to the shaft shoulder of bent axle spindle nose section 12 and bent axle latter end 15, bent axle spindle nose section 12 and bent axle latter end 15 are given by spacer ring on the crank pin 14 08 and connecting rod tip aligning roller axle 07 inner ring end face and are tightly tried hard to recommend to bent axle intermediate section 13, realize being rigidly connected of crankshaft support section.The axial positioning structure of crank pin 14 is: after the crankshaft support section assembling and positioning, with bolt bearing pin footstock 03 is fixedly connected on the bent axle latter end 15, tighten on the bearing pin footstock 03 Cock screw 04 throw crank bearing pin 14 along axis forward, utilize on crank pin 14 end faces with the intersection of other crank pin 14 end faces the pressure of Cock screw 04 is transmitted through terminal crank pin 14 mutually.Can make crankshaft group and crank pin be assembled into the integral body of rigidity like this, structure is very reasonable.Crosshead 16 realizes hinged by crosshead pin 18 and wrist-pin end of connecting rod selfaligning roller bearing 19 with wrist-pin end of connecting rod 17.
Working procedure is summarized as follows: when the motion of actuator devices is to-and-fro motion, the rotation of prime mover is imported into by bent axle spindle nose section 12, and the driving lower crank bearing pin 14 of eccentric pin-and-hole promotes bent axle intermediate sections 13 and bent axle latter end 15 together around the rotational of crankshaft support section on bent axle spindle nose section 12; Under the constraint of the cylindrical of crank pin 14, connecting rod tip 06 is radius with its center of circle to the distance at crankshaft support center with crank pin 14, make circular movement around crankshaft support section axis, meanwhile, under the restriction of the cylinder slideway of body 02, with the hinged crosshead 16 of wrist-pin end of connecting rod 17 along with crosshead pin 18 is done straight reciprocating motion.When the motion of actuator devices when rotatablely moving, the movement process of crank mechanism is opposite with summary, can know (referring to Fig. 6, Fig. 7) by inference.
In the crank mechanism of multi-joint forms of motion, the bent axle of the utility model scheme is easy to realize multi-point support, compare with traditional integral formula bent axle, the bent axle of conventional construction is because of the restriction of structural condition, can only adopt the two-end-point supporting of big span, cause former train of mechanism rigidity relatively poor, and the utility model scheme multi-point support structure makes the force-bearing situation of crank can be reduced to simply supported beam between any 2 supportings, the rigidity and the intensity of bent axle are increased, and help bearing bigger moment of flexure (piston force).
The processing technology of bent axle is simplified and optimized to the utility model scheme in the crank mechanism of multi-joint forms of motion.Compare with traditional integral formula bent axle, former workpiece is had relatively high expectations because of its casting of profile or the Forging Technology of blank complexity, and casting of the blank of the utility model scheme or Forging Technology want much simple; Aspect mechanical processing technique, because its overall structure workpiece is complex-shaped, the tolerance of size of workpiece and the required precision of form and position tolerance are difficult to guarantee, and the utility model scheme is because of resolving into original structure the combination of several simple geometry bodies, and its tolerance of size and form and position tolerance then are easy to be controlled; Aspect heat treatment process, because giving, its complicated geometrical shape of integrally-built bent axle wants to have brought difficulty by obtaining comprehensive physical property and mechanical property with local processing method, the utility model scheme is then much easier.
Conclusion is got up, owing to adopted combined type crank pin structure, so present embodiment can adopt the integrated type connecting rod, and has following characteristics:
1, the structure of integrated type connecting rod tip makes the intensity of con-rod only and rigidity increase.
2, the structure of integrated type connecting rod tip makes the machining work process of connecting rod workpiece compare with the machining work process of the connecting rod workpiece of middle open type connecting rod tip structure and wants much simple.
3, the structure of integrated type connecting rod tip makes the connecting rod workpiece obtain higher dimensional accuracy and form and position tolerance precision easily in process for machining.
4, the structure of integrated type connecting rod tip in assembling because itself and the supporting form of eccentric shaft employing selfaligning roller bearing; The supporting form of wrist-pin end of connecting rod and crosshead pin adopts selfaligning roller bearing, this assembly structure can be eliminated when assembling and the contact stress that produces in the motion to greatest extent, to guarantee mechanism's smoothness of moving at work, make mechanism obtain higher mechanical efficiency at work.
5, the structure of integrated type connecting rod tip is because the motion mode of its kinematic pair adopts in the utility model scheme is rolling friction, the lubricating condition of its kinematic pair requires to compare with the lubricating condition requirement of sliding friction much simple, only need adopt splash lubrication to annotate the lubricating requirement that lubricating grease just can satisfy motion with giving to kinematic pair at the volley.
In addition to the implementation, the utility model can also have other mode of executions.All employings are equal to the technological scheme of replacement or equivalent transformation formation, all drop on the protection domain of the utility model requirement.