CN201293007Y - Amortization structure suitable for hydraulic cylinder tail end - Google Patents
Amortization structure suitable for hydraulic cylinder tail end Download PDFInfo
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- CN201293007Y CN201293007Y CNU2008202209789U CN200820220978U CN201293007Y CN 201293007 Y CN201293007 Y CN 201293007Y CN U2008202209789 U CNU2008202209789 U CN U2008202209789U CN 200820220978 U CN200820220978 U CN 200820220978U CN 201293007 Y CN201293007 Y CN 201293007Y
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Abstract
The utility model relates to a buffer structure applied to the tail end of a hydraulic cylinder, comprising the hydraulic cylinder, as well as a piston and a piston rod which are installed in the cavity of the hydraulic cylinder. The buffer structure is characterized in that a nut sleeve (18) with a conical chamfer arranged at the rear end is installed at the tail end of the piston rod (21) positioned in a non-rod chamber of the hydraulic cylinder, and the piston (19) and the piston rod (21) are firmly connected into a whole through the rotary extrusion and the pushing of the front end surface of the nut sleeve (18); a buffer jacket (15) matched with the excircle surface of the nut sleeve (18) and a hole-used elastic collar (16)for limiting the axial stroke of the buffer jacket (15) are installed in a step oil duct chamber which is perpendicular to an oil port at a cylinder tail (13). The buffer structure is applied to the situation that the tail end of the hydraulic cylinder is required to be buffered because the retract speed of the piston rod in a hydraulic system is too fast and can also solve the problem that piston rods are not synchronous to extend when a plurality of hydraulic cylinders are operated in parallel.
Description
Technical field
The utility model relates to a kind of hydraulics, relates to a kind of buffer structure that is applicable to oil hydraulic cylinder cylinder tail end specifically.
Background technique
In engineering machinery, adopt oil hydraulic cylinder as the executive component in the hydraulic system in a large number, and as the motion rod member in the engineering machinery mechanism.In general, when each mechanism kinematic action of engineering machinery, always wish rod member stable action, reliable, do not stop rapidly suddenly, in order to avoid cause impact and damage to mechanism.Therefore the oil hydraulic cylinder that uses in the engineering machinery motion generally all can satisfy the requirement of mechanism to the hydraulic cylinder piston rod motion at hydraulic cylinder piston rod end and cylinder tail end design buffer structure.
The normal buffer structure that adopts of the oil hydraulic cylinder cylinder tail end (referring to Fig. 1, Fig. 2) of prior art be the inner hole surface φ A that utilizes cylinder tail head with piston rod tail end axle periphery φ B between matching gap carry out throttling and cushion.The space that space between the end face of piston rear end face and cylinder tail head and cylinder tail head hold the piston rod tail end diameter of axle---the fluid that is in the buffer cavity to be contained, need flow to oil hydraulic cylinder rodless cavity hydraulic fluid port by the two matching gap of φ A/ φ B, and discharge fluid to hydraulic system.The inner hole surface φ A of cylinder tail head and the slit between the piston rod tail end axle periphery φ B are equivalent to a throttle valve at this moment, therefore just play buffer function.
But the oil hydraulic cylinder of above-mentioned buffer structure is used in (as the boom cylinder of loader) on the engineering machinery, can have following problem: oil hydraulic cylinder at piston rod when withdrawing fully, catching sight of in fact sometimes, oil hydraulic cylinder does not have pooling feature, therefore to piston rod withdrawal stroke end, piston rear end is very fierce in the face of the cylinder tail end surface impact of oil hydraulic cylinder.Analyzing the reason that this situation occurs, is because the inner hole surface φ A and the matching gap between the piston rod tail end axle periphery φ B of cylinder tail end are too big, does not have the effect of throttling buffering.
By mathematical modeling and design of Simulation, the throttling cushioning effect that discovery will be realized ideal, it is very high that the machining deviation in the slit between the inner hole surface φ A of cylinder tail end and the piston rod tail end axle periphery φ B requires.So-called perfect condition be meant piston rod tail end diameter of axle φ B, cylinder tail head endoporus φ A following structural element longitudinal center line mutually between, and between they and the oil hydraulic cylinder longitudinal center line, preferably being in theory coaxality is zero, and the throttling cushioning effect is then decided by the two matching gap of φ A/ φ B fully:
1) the assembly longitudinal center line behind the affixed installation piston rod of piston and the coaxality of cylinder barrel inner hole centreline;
2) cylinder tail head cooperates the cylinder barrel inner hole centreline of welding back formation and the coaxality of cylinder tail head endoporus φ A with the cylinder barrel seam.
Because, remove some working surfaces on the processing cylinder tail head after cylinder tail head and cylinder barrel welding again, difficulty is too big, so before the general employing welding working surface on the cylinder tail head is processed earlier, rely on the seam quality of fit of cylinder tail head and cylinder barrel to position then, implement welding.Because postwelding do not reprocess,, make φ A center line and this part center line decentraction of the cylinder barrel in the cylinder barrel of manufactured cylinder tail head so always have certain welding deformation.Therefore, after piston and piston rod assembly are installed in the cylinder barrel, between the center line of this assembly and the cylinder tail head endoporus φ A center line suitable eccentricity value is always arranged.
Just because of the manufacturing cumulative error of each part is very big, so the actual eccentricity value after the assembling of parts such as piston, piston rod is sometimes greater than matching gap between the φ A/ φ B of cylinder tail head endoporus and piston rod tail end cylindrical.Will when the related piston rod of piston enters the cylinder tail end and wants to cushion the defect of piston rod tail end axle φ B bump cylinder tail head endoporus φ A appear but like this.Appearance for fear of this phenomenon, design or make just will consider the buffering aperture φ A that amplifies on the cylinder tail head and the matching gap numerical value of piston rod tail end shaft diameter φ B, its direct result is exactly to make to allow the cylinder tail end buffer loss function of oil hydraulic cylinder and clash between piston end surface and the cylinder tail end surface.
Summary of the invention
The purpose of this utility model provides a kind of buffer structure that is applicable to oil hydraulic cylinder cylinder tail end at existing deficiency in the above-mentioned prior art just.This is rational in infrastructure, novel, and cushioning effect is obvious, in the time of effectively solving piston rod and be withdrawn into terminal, and cylinder tail end buffer problem; Also make when many hydraulic cylinder piston rods of parallel operation stretch out in hydraulic system simultaneously, can realize synchronization motion, start rapid, steady.
The purpose of this utility model can realize by following technique measures:
The buffer structure of oil hydraulic cylinder cylinder tail end that is applicable to of the present utility model comprises hydraulic cylinder and is installed in hydraulic cylinder cavity interior piston and piston rod, at the piston rod tail end that is positioned at the oil hydraulic cylinder rodless cavity nut sleeve that the rear end is processed with the taper chamfering is installed, and the front-end face spinning pushing tow by this nut sleeve with piston, piston rod is affixed is integral; With the step-like oil duct chamber of the perpendicular setting of rodless cavity hydraulic fluid port of cylinder tail head in the cushion collar that matches with nut sleeve rear end periphery is installed, and the circlip for hole that is used to limit the cushion collar axial stroke.
The lateral projection of the cushion collar described in the utility model is the convex shape structure, and the external diameter of its larger diameter end is slightly less than the major diameter oil duct section internal diameter in step-like oil duct chamber, and the external diameter of its smaller diameter end is slightly less than the minor diameter oil duct section internal diameter in step-like oil duct chamber; On the end face of this cushion collar, be processed with several radially oil grooves, on the periphery of this cushion collar smaller diameter end, be processed with several axial oil grooves with respect to the larger diameter end of piston side.
Cushion collar with radial and axial float function is set in the structure of the present utility model to be installed in the step-like oil duct of cylinder tail head, cushion with the affixed nut sleeve diameter of axle cylindrical that is installed in the piston rod tail end, can be used for the occasion that the requirement oil hydraulic cylinder has cylinder tail end buffering.More specifically say: the radial floating of cushion collar can make its endoporus cooperate with nut sleeve taper chamfering, forms automatic centering, compensates each part processing cumulative error; The axial float of cushion collar can make one side and cylinder tail caster bed scalariform oil duct end face applying oil sealing, utilizes the matching gap between the cylinder tail head aperture and the nut sleeve diameter of axle to carry out cylinder tail end throttling buffering.
When the application piston bar stretches out, cushion collar is under the pressure oil effect that comes from hydraulic fluid port, move axially to piston side, fluid can by the axial oil groove that is provided with on the cushion collar and radially oil groove rapidly to the rapid oil-feed in oil hydraulic cylinder rodless cavity space, when solving many oil hydraulic cylinder parallel operations, piston rod stretches out nonsynchronous problem.
The beneficial effects of the utility model are as follows:
Because the utility model has the radial floating ability by cushion collar, make automatic centering between nut sleeve periphery and the cushion collar inner headed face carry out the throttling buffering of cylinder tail end, so can effectively compensate because the error of form and position tolerances such as coaxality, perpendicularity between each part such as the piston that causes of machining error, piston rod also reduces the required precision to each part processing size simultaneously.
In addition, because cushion collar also has the axial float ability, when piston rod is withdrawn, the taper chamfered part of the nut sleeve of installing on the piston rod tail end axle enters into the cushion collar endoporus fully, when forming pressure chamber (being buffer cavity) between piston rear end face and the cylinder tail caster bed scalariform oil duct, pressure oil passes through to promote the larger diameter end of cushion collar to one lateral movement of rodless cavity hydraulic fluid port, the larger diameter end interior edge face of cushion collar is close to oil sealing (even be not that face contacts, also can be line contact oil sealing) with the step end face of cylinder tail caster bed scalariform oil duct.Fluid in the above-mentioned like this buffer cavity can only slowly flow to the outside oil extraction of rodless cavity hydraulic fluid port by between the slit of cushioning matching pair, cylinder tail end buffer function when having played the hydraulic cylinder piston rod withdrawal.
When the oil-feed of rodless cavity hydraulic fluid port, pressure oil has two routes that lead to rodless cavity:
One between the slit by buffering matching pair φ E/ φ F, slowly flows to rodless cavity;
Its two, pressure oil promotes cushion collar and moves to piston side, and is being kept off by back-up ring.At this moment, pressure oil is by the cushion collar axial oil groove, be full of the rodless cavity space rapidly through oil groove radially again.
In above-mentioned two logical oil circuit lines, the logical oil mass of second route is more much bigger than article one, so can be so that pressure oil almost has been full of rodless cavity soon.This particular importance when many oil hydraulic cylinder parallel operations are arranged in the hydraulic system, promptly piston rod can almost be done simultaneously and stretched out action this moment, and many hydraulic cylinder piston rods can be synchronized with the movement, and this stability to the mechanism action of engineering machinery is of great benefit to.
Description of drawings
Fig. 1 is the oil hydraulic cylinder cylinder tail end buffer structure schematic representation of prior art.
Fig. 2 is the I partial view of Fig. 1.
Fig. 3 is an oil hydraulic cylinder cylinder tail end buffer structure schematic representation of the present utility model.
Fig. 4 is the II partial view of Fig. 3.
Sequence number is among Fig. 1 and Fig. 2: 1, cylinder tail head, 2, hydraulic fluid port (rodless cavity hydraulic fluid port), 3, the ear end face of piston, 4, piston, 5, cylinder barrel, 6, piston rod, 7, the end face of cylinder tail head, 8, the step end face of cylinder tail caster bed scalariform oil duct, 9, the end face of piston rod tail end, 10, card key, 11, card key cover, 12, back-up ring (circlip for shaft).
Sequence number is among Fig. 3 and Fig. 4: 13, cylinder tail head, 14, hydraulic fluid port (rodless cavity hydraulic fluid port), 15, cushion collar, 16, back-up ring (circlip for hole), 17, the end face of cylinder tail head, 18, nut sleeve, 19, piston, 20, cylinder barrel, 21, piston rod, the ear end face of 22 pistons, 23, the step end face of cylinder tail caster bed scalariform oil duct, 24, the end face of piston rod tail end, 25, screw, 26, axial oil groove, 27, oil groove radially.
Embodiment
The utility model is further described below with reference to embodiment's (accompanying drawing), but does not limit the utility model.
Shown in Figure 4 as Fig. 3, the structure characteristic of the buffer structure that is applicable to oil hydraulic cylinder cylinder tail end of the present utility model is as follows: at piston rod 21 tail ends that are positioned at the oil hydraulic cylinder rodless cavity nut sleeve 18 that the rear end is processed with the taper chamfering is installed, and the front-end face by this nut sleeve 18 and screw 21 are with piston 19, piston rod 21 affixed being integral; With the step-like oil duct chamber of the rodless cavity hydraulic fluid port 14 perpendicular settings of cylinder tail head 13 in the cushion collar 15 that matches with nut sleeve 18 rear end peripheries is installed, and the circlip for hole 16 that is used to limit cushion collar 15 axial stroke; The lateral projection of described cushion collar 15 is the convex shape structure, and the external diameter of its larger diameter end is slightly less than the major diameter oil duct section internal diameter in step-like oil duct chamber, and the external diameter of its smaller diameter end is slightly less than the minor diameter oil duct section internal diameter in step-like oil duct chamber; On the end face of this cushion collar, be processed with several radially oil grooves 27, on the periphery of this cushion collar smaller diameter end, be processed with several axial oil grooves 26 with respect to the larger diameter end of piston side.
Concrete working method of the present utility model and principle are as follows:
When piston rod 21 when withdrawing fully, the diameter of axle φ F band taper chamfered part of the nut sleeve 18 on the piston rod tail end extend in the φ E hole of cushion collar 15, because cushion collar 15 has the radial floating function, so the process that stretches into can automatic centering between them.
Two annuluses that form between piston rear end face 22 and cylinder tail end surface 17, the end face 23 are buffer cavity.When the oil hydraulic cylinder rod chamber continues to enter pressure oil pushing tow piston 19, piston 19 and piston rod 21 still can be done retraction movement, make oil liquid pressure in the buffer cavity raise and increase.At this moment cushion collar 15 can be drawn close to step end face 23 motions in cylinder tail caster bed scalariform oil duct chamber, and the applying oil sealing.The oil sealing state may be face contact oil sealing, also may be line contact oil sealing.
At this moment piston rod tail end band nut sleeve 18 axially moves to cushion collar 15 these sides together, and the fluid in the buffer cavity carries out the throttling buffering by the gap of nut sleeve 18 diameter of axle φ F and cushion collar 15 aperture φ E, exports fluid from hydraulic fluid port 14 to hydraulic system.
For oil hydraulic cylinder, the control of piston rod withdrawal stroke generally can not adopted fully and be controlled by hydraulic cylinder travel, promptly in Fig. 1, can not allow piston rod 6 withdraw fully after, piston end surface 3 and 7 applyings of cylinder tail end surface; In Fig. 3, can not allow piston end surface 22 and cylinder tail end surface 17 fit.Because for every oil hydraulic cylinder of same plant produced, same specification, their actual size is also incomplete same, so the stroke of hydraulic cylinder piston rod withdrawal in fact also is not the same.During for many oil hydraulic cylinder parallel operations, control with hydraulic cylinder piston rod withdrawal stroke, a result wherein hydraulic cylinder piston rod withdrawal stroke finishes, and the another oil hydraulic cylinder is also continuing to do the piston rod retraction movement, this will make the rod member of the parallel kinematic in the mechanism be subjected to extra load, therefore seems extremely unreasonable.
Reasonably design should be taked mechanical stop limiter in mechanism, when allowing the oil hydraulic cylinder buffering finish, is the existing structure of example with Fig. 1,1/3～1/4 of the L1 the when distance L 2 between piston end surface 3 and the cylinder tail end surface 7 has just begun for buffering; With Fig. 3 is the utility model structure of example, 1/3～1/4 of the L3 the when distance L 4 when the oil hydraulic cylinder buffering finishes between the end face 17 of piston end surface 22 and cylinder tail end has just begun for buffering.Because distance can't direct observation in the cylinder, so normally allowing piston rod withdrawal stroke stay has the dimensions, as stay 10mm～30mm to design mechanical stop limiter, and make oil hydraulic cylinder almost finish piston rod retraction movement stroke simultaneously, avoid that other rod members are subjected to extra load in the mechanism.
When the application piston bar stretched out, the pressure oil of the rodless cavity hydraulic fluid port 2 of existing structure just can only be by the slit of buffering matching pair φ A/ φ B, slowly entered into the rodless cavity of formation between the end face 7, end face 8 of piston end surface 3 and cylinder tail head.Have only when the oil pressure in the rodless cavity is elevated to certain numerical value, the thrust that is produced is just understood pushing tow piston end surface 3 and is blocked key cover 11, back-up ring 12, makes piston rod 6 produce and stretches out action.Therefore, stretch out from beginning application piston bar 6, to its real action, needed time is longer, and the action that seems lags behind.Especially when many oil hydraulic cylinder parallel operations are arranged in the hydraulic system, because the rodless cavity volume size of each oil hydraulic cylinder is not exclusively equal; The slit of the buffering matching pair φ A/ φ B of each oil hydraulic cylinder is also not exclusively equal, stretches out the asynchronous of action so will form piston rod, causes that rod member is subjected to additional load in the mechanism, seems very unreasonable.
The utility model structure is under the pressure oil effect of rodless cavity hydraulic fluid port 14, cushion collar 15 towards piston end surface 22 1 side shafts to moving, till being kept off by back-up ring 16 to it.The axial oil groove of pressure oil this moment by the cushion collar 15 that floats has been full of rodless cavity rapidly through oil groove radially again.
Because this novel practical structure can be to the rapid oil transportation in oil hydraulic cylinder rodless cavity space, rodless cavity is set up normally pushing tow piston soon, allows piston rod do and stretches out the pressure oil pressure of action.When pressure oil acts on thrust on the piston end surface 22 when reaching certain numerical value, piston rod 21 is just very fast protruding, has therefore also just realized many problems that hydraulic cylinder piston rod stretches out synchronously.
The piston fixing structure of existing structure is such: piston 4 is sleeved on the piston rod 6, be inserted in the groove of piston rod with two Semicircular card keys 10, be enclosed within card key 10 outsides with card key cover 11 again, do not allow card key 10 drop out, will block key with circlip for shaft 12 then and overlap 11 axial restraints.
Piston fixing structure of the present utility model then is such: by being threaded, affixed after piston 19 assembles with piston rod 21 with piston rod 21 with nut sleeve 18, and play piston shaft to positioning action; Loosening for preventing to be threaded, at the screw thread junction of the edges of two sheets of paper place drilling and tapping of nut sleeve 18, a screw 25 is installed with piston rod 16.They make between piston 19 and the piston rod 21 affixed.
On nut sleeve 18, mill flat side (or processing bore some apertures),, make itself and end face 22 applyings of piston 19 so that tool using is rotated nut sleeve 18.
Occasion too fast because of the piston rod retraction speed in the hydraulic system, that oil hydraulic cylinder cylinder tail end need cushion that the utility model is applicable to, particularly relatively large to cylinder diameter oil hydraulic cylinder for guaranteeing its normal use, seems more suitable.
Claims (2)
1, a kind of buffer structure that is applicable to oil hydraulic cylinder cylinder tail end, it comprises hydraulic cylinder and is installed in hydraulic cylinder cavity interior piston and piston rod, it is characterized in that: piston rod (21) tail end that is positioned at the oil hydraulic cylinder rodless cavity is equipped with the nut sleeve (18) that the rear end is processed with the taper chamfering, and the front-end face spinning pushing tow by this nut sleeve (18) is with piston (19), affixed being integral of piston rod (21); With the step-like oil duct chamber of the perpendicular setting of hydraulic fluid port (14) of cylinder tail head (13) in the cushion collar (15) that matches with nut sleeve (18) periphery is installed, and the circlip for hole (16) that is used to limit cushion collar (15) axial stroke.
2, buffer structure according to claim 1, it is characterized in that: the lateral projection of described cushion collar (15) is the convex shape structure, the external diameter of its larger diameter end is slightly less than the major diameter oil duct section internal diameter in step-like oil duct chamber, and the external diameter of its smaller diameter end is slightly less than the minor diameter oil duct section internal diameter in step-like oil duct chamber; On the end face of this cushion collar, be processed with several radially oil grooves (27), on the periphery of this cushion collar smaller diameter end, be processed with several axial oil grooves (26) with respect to the larger diameter end of piston side.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2008202209789U CN201293007Y (en) | 2008-11-17 | 2008-11-17 | Amortization structure suitable for hydraulic cylinder tail end |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2008202209789U CN201293007Y (en) | 2008-11-17 | 2008-11-17 | Amortization structure suitable for hydraulic cylinder tail end |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201293007Y true CN201293007Y (en) | 2009-08-19 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2008202209789U Expired - Fee Related CN201293007Y (en) | 2008-11-17 | 2008-11-17 | Amortization structure suitable for hydraulic cylinder tail end |
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| Country | Link |
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| CN (1) | CN201293007Y (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102384125A (en) * | 2011-05-24 | 2012-03-21 | 四川重汽王牌兴城液压件有限公司 | Hydraulic executing device of heavy truck dumper |
| CN102705294A (en) * | 2012-06-26 | 2012-10-03 | 上海三一重机有限公司 | High-pressure cylinder and excavator comprising same |
| CN102720727A (en) * | 2012-06-15 | 2012-10-10 | 常州液压成套设备厂有限公司 | Furnace cover oil cylinder with back buffer function |
| CN109595217A (en) * | 2019-01-02 | 2019-04-09 | 中船重工中南装备有限责任公司 | The oil cylinder of asphalt channel built in a kind of band |
| CN111765141A (en) * | 2020-06-29 | 2020-10-13 | 徐州徐工随车起重机有限公司 | Bidirectional impact-proof hydraulic telescopic oil cylinder for lorry-mounted crane |
| WO2023116044A1 (en) * | 2021-12-20 | 2023-06-29 | 娄底市中兴液压件有限公司 | Hydraulic cylinder, hydraulic system, and operation machinery |
-
2008
- 2008-11-17 CN CNU2008202209789U patent/CN201293007Y/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102384125A (en) * | 2011-05-24 | 2012-03-21 | 四川重汽王牌兴城液压件有限公司 | Hydraulic executing device of heavy truck dumper |
| CN102384125B (en) * | 2011-05-24 | 2014-01-15 | 四川重汽王牌兴城液压件有限公司 | Hydraulic executing device of heavy truck dumper |
| CN102720727A (en) * | 2012-06-15 | 2012-10-10 | 常州液压成套设备厂有限公司 | Furnace cover oil cylinder with back buffer function |
| CN102705294A (en) * | 2012-06-26 | 2012-10-03 | 上海三一重机有限公司 | High-pressure cylinder and excavator comprising same |
| CN109595217A (en) * | 2019-01-02 | 2019-04-09 | 中船重工中南装备有限责任公司 | The oil cylinder of asphalt channel built in a kind of band |
| CN109595217B (en) * | 2019-01-02 | 2023-12-05 | 中船重工中南装备有限责任公司 | Oil cylinder with built-in oil way channel |
| CN111765141A (en) * | 2020-06-29 | 2020-10-13 | 徐州徐工随车起重机有限公司 | Bidirectional impact-proof hydraulic telescopic oil cylinder for lorry-mounted crane |
| WO2023116044A1 (en) * | 2021-12-20 | 2023-06-29 | 娄底市中兴液压件有限公司 | Hydraulic cylinder, hydraulic system, and operation machinery |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20090819 Termination date: 20131117 |