Closed type static pressure turntable and external clamping structure thereof
Technical field
This novel mechanical production devices that relates to, i.e. closed type static pressure turntable in the lathe and external clamping structure thereof.
Technical background
The developing direction of modern Digit Control Machine Tool is high speed, high moment of torsion, high-mechanic " three height " trend, and to as the lathe important component part---the requirement of guide rail is also in continuous raising: precision height, rigidity and bearing capacity are big, coefficient of friction is low.Therefore, all can not satisfy above-mentioned requirements completely, withdraw from modern machine designers' first-selected scope gradually as traditional edge steel plastic-sticking guiding rail pair the most commonly used at present, rolling linear guide etc.Though and the novel load-carrying line slideway can satisfy the straight-line demand of lathe, but be difficult to satisfy the requirement of the ring-like guide rail of rotating table of numerical control machine.Therefore, based on the static pressure principle have the bearing capacity height, the various guide rails of plurality of advantages such as coefficient of friction is minimum, rigidity is big, precision stability is good more and more are applied in the middle of the design of modern machine.Particularly large and medium-sized Digit Control Machine Tool is because that the user requires the bearing capacity of machine tool rotary working table, rotating speed etc. is more and more higher, so can increase bearing capacity greatly, the static pressure structure that reduces coefficient of friction becomes first-selection.At present, modern large and medium-sized Digit Control Machine Tool is used static pressure principle rotary table, employing be open type static pressure structure.This kind structure has solved the problem that bearing capacity is low, coefficient of friction is big that conventional guide rails runs into, but, because it bears the unbalance loading ability, and the floatation volume when uncontrollable rotary table static pressure floats, cause its machining accuracy to can not get guaranteeing, thereby run into the design bottleneck, many designers are hung back to it.
In addition, the built-in dish spring that the tradition rotary table is used clamps, the binding clasp of hydraulic unlock, though because clamping force is big and reliable, and be widely used so far, but because it need take too many belt guide rail space, significantly reduce the static pressure loaded area of hydrostatic slideway, had a strong impact on the load-carrying properties of hydrostatic slideway.And as this kind principle is applied to the external binding clasp, good because its volume is excessive again by everybody.The unidirectional plunger binding clasp of existing external after clamping, because two intermetallic diffusion phenomena cause two contact-making surfaces bonding, causes unclamping difficulty, and seldom is used.Therefore, modern large and medium-sized rotating table of numerical control machine urgent need is a kind of not to take inner space (external), and the reliable binding clasp of clamping and release substitutes existing binding clasp, the problem that solution exists at present.
Summary of the invention
This novel purpose provides a kind of closed type static pressure turntable and external clamping structure thereof, has solved the determine problem of the uncontrollable static pressure of open type static pressure structure rotary table floatation volume when floating of large and medium-sized Digit Control Machine Tool.
This closed type static pressure turntable and external clamping structure thereof, be equipped on the large and medium-sized Digit Control Machine Tool, comprise multi-head pump by the hydraulic power unit fuel feeding, piston driver, it is characterized in that the work table rotation stage body lower cylindrical and the endoporus of bull gear adopt coaxial basic hole system matched in clearance, bull gear is fixed on the workbench and drops on jointly on the slide, be processed with the opposite guideway of upper surface decomposition pressure of static pressure oil pocket on the bull gear bottom surface with higher level degree and fineness and the slide; The compartment of terrain is provided with pressing plate and bidirectional piston binding clasp in the space of bull gear periphery protrusion workbench, pressing plate has the static pressure oil pocket that docks with edge static pressure piece thereon, the static pressure oil pocket all is communicated with the flowline of quantitative multi-head pump with static pressure oil pocket on the pressing plate on the slide, and pressing plate and slide provide static pressure oil for respectively the upper and lower surface of guideway; The upper and lower part of bidirectional piston binding clasp is placed in the above and below of bull gear, and each binding clasp has six pistons; The drive unit of being made up of gear reduction box is installed in the slide side, and moment of torsion is transmitted in two gears of drive unit and bull gear engagement, drives work table rotation.
Bear unbalance loading ability, frictional force and be difficult to high speed rotary, the uncontrolled problem of levitation height greatly for solving traditional rotary table, closed type static pressure turntable of the present invention has been used quantitative static pressure principle, pull having installed to press as the bull gear upper surface of the ring-like guideway part of revolution, for panoramic table has increased constraint, reduced its free degree, made the one degree of freedom on its only remaining gyratory directions; And on pressing plate, inlayed the copper coin that has the static pressure chamber, formed the closed type static pressure structure.The static pressure oil pressure on the upper and lower surface of bull gear is with the workpiece load dynamic response on the panoramic table, regulates voluntarily in this structure, therefore no matter the payload of panoramic table, unbalance loading whether, the upper and lower surface of bull gear can both be born the equalization pressure of static pressure oil simultaneously; The static pressure that workbench lower cylindrical supporting surface forms is mainly used to offset the weight of rotary table itself and workpiece, the pressing plate of upper support face and the static pressure of generation thereof then are used for stoping the random rising of panoramic table, make the floatation volume of panoramic table stable within the specific limits.The characteristics of closed type static pressure structure rotary table are, not only possessed advantages such as traditional open type static pressure turntable bearing capacity is big, coefficient of friction is little, rigidity is high, precision stability is good, also, its closed type structure bears the advantage that the unbalance loading ability is strong, levitation height is stable because of having increased, make the large and medium-sized numerical control machine tool that this workbench is installed increase bearing capacity, improve machining accuracy, and for the high speed after the heavy duty of panoramic table, revolution has stayed sufficient space reposefully.
Outer clamping structure is to place four clamp mechanism of symmetry between the space of each pressing plate.Each clamp mechanism is divided into upper and lower two binding clasps, and each binding clasp has three pistons, and clamping in the body has oil circuit can make pressure oil arrive upper and lower two stress surfaces of each piston.When need clamped, the piston of upper and lower binding clasp was subjected to oil pressure simultaneously protruding, clamped the upper and lower surface of bull gear respectively; When need unclamp, the withdrawal of piston pressurized, panoramic table can freely turn round.Safe and reliable when clamp mechanism clamps, precise and stable during operation.Because this binding clasp is installed in the workbench periphery, the I﹠M of returning lathe provides advantage, has reduced man-hour, has reduced cost.
Description of drawings
Fig. 1 is a closed type static pressure panoramic table structural section schematic diagram;
Fig. 2 is a closed type static pressure panoramic table static pressure structural profile schematic diagram;
Fig. 3 is a bidirectional piston binding clasp structural profile schematic diagram;
Fig. 4 is pressing plate and static pressure piece generalized section;
Fig. 5 goes up the binding clasp generalized section;
Fig. 6 is a bidirectional piston binding clasp hydraulic schematic diagram;
The specific embodiment
Closed type static pressure turntable and external clamping structure thereof, be equipped in big, on the medium-sized Digit Control Machine Tool, comprise multi-head pump by the hydraulic power unit fuel feeding, piston driver, it is characterized in that it being the panoramic table that removes workbench, adopt the closed type static pressure structure, see Fig. 2: bull gear 4 is installed in workbench turntable body 5 bottoms, workbench turntable body 5 lower cylindrical adopt coaxial basic hole system matched in clearance with the endoporus of bull gear 4, drop on jointly on the slide 3, the compartment of terrain is provided with pressing plate 1 and clamp mechanism 2 in the space of bull gear 4 protrusion workbench turntable bodies 5, see Fig. 1: be evenly distributed in each 135 ° of scope of drive unit both sides, four clamp mechanism 2 are spaced apart and arranged between the pressing plate 1, form higher level degree and fineness.
The shape of pressing plate 1: see Fig. 4; Rectangular block, its long limit is radian slightly, and in inner arc one side notch is arranged, in oil pocket is arranged, the oil pocket end is perpendicular to the notch middle part, 7 holes of its upper surface are the fixing screw holes; Static pressure piece 6 is all rectangle with pressing plate 1, static pressure piece 6 width are less than the notch length of pressing plate 1, it highly equals the notch height, the one side central concave also has oilhole, oil pocket end in the pressing plate 1 docks with the oilhole of edge static pressure piece 6 thereon, be processed with O RunddichtringO groove at the oilhole back side of static pressure piece 6, place the O RunddichtringO, prevent that static pressure oil is excessive from faying face.
In addition, flatness and fineness in order to guarantee to contact with slide 3 upper surfaces, workbench turntable body 5 bottoms are less than the height of bull gear 4 as the column part height of location, and the counterbore part of trip bolt and taper bolt is blocked up employing interference fit jam-pack with copper after, through whole grinding, guarantee the flatness of bull gear 4 lower surfaces, and the depth of parallelism of bull gear 4 lower surfaces and table surface.
The top 7 of the bidirectional piston binding clasp of clamp mechanism 2, bottom 8 are placed in the above and below of bull gear 4, see Fig. 3: each binding clasp has six pistons 9, and top and the bottom respectively have three.The shape description of binding clasp: see Fig. 5, T shape post is arranged in the top 7, and two vertical with it static pressure oil pocket oil circuits are arranged, the T shape hole of similar shape is arranged in the bottom 8 and vertical with it static pressure oil pocket oil circuit is arranged, the oil pocket end connects piston 9 circle centre positions separately, and another oil-in is aimed at piston 9 path walls.The length of piston 9 will satisfy the flat or indentation of 10 on when withdrawal and gland a bit, and just must guarantee can clamp bull gear 4 when upper and lower two pistons 9 stretch out simultaneously above more than the 0.5mm when stretching out.The drive unit of being made up of gear reduction box 11 is installed in slide 3 circumference sides, and moment of torsion is transmitted in two gears of drive unit 11 and bull gear 4 engagements, drives work table rotation.
It is that 4~5bar, flow are that the hydraulic oil of 6L/min is used for supplying with workbench turntable body 5 static pressure and capturees that hydraulic power unit will provide pressure.Hydraulic oil is connected respectively to advancing by oil port of three quantitative multi-head pumps by pumping plant through the attaching type sebific duct, flow be 6L/min hydraulic oil through three multi-head pumps after, be divided into 30 the tunnel, every road flow 0.2L/min.Wherein a part is connected to fuel feed hole on the slide 3 via the red copper pipeline, and the static pressure oilhole from slide 3 flows out, and forms power upwards.And two copper static pressure pieces 6 are installed on every pressing plate 1, and the static pressure chamber is arranged on the static pressure piece 6, oilhole is arranged in the chamber.The hydraulic oil of multi-head pump remainder is connected respectively to 12 fuel feed holes on six pressing plates 1 via the red copper pipeline, flows to the downward power of formation in the static pressure chamber on the static pressure piece 6 at last.
As shown in Fig. 6 hydraulic schematic diagram, when need clamped, solenoid directional control valve P mouth was communicated with the A mouth, and the T mouth is communicated with the B mouth, and the pressure oil of 40bar pressure leads to the big end of piston 9 big ends circle centre position, and all pistons stretch out, and clamp bull gear 4 simultaneously from upper and lower both direction; When need unclamped, solenoid directional control valve P mouth was communicated with the B mouth, and the T mouth is communicated with the A mouth, and the pressure oil of 10bar pressure leads to piston 9 small ends, all piston-retraction, and the bull gear 4 of clamping is decontroled, and can freely turn round; When solenoid directional control valve was in meta, mechanism was in packing state, and the piston 9 in the binding clasp can keep original stretching out or retracted mode.Because number of pistons is more in the binding clasp, and clamps simultaneously from upper and lower both direction, therefore, hydraulic oil only needs the pressure of 40bar during clamping; And when unclamping, only need overcome the diffusion phenomena of 4 of part piston 9 clamping areas and bull gears, so only need the pressure oil of 10bar pressure.This shows that this binding clasp not only is evenly distributed, steps up reliable, and the pressure of required pressure oil is less, relatively saves the energy.
Bull gear 4 bottom surfaces with higher level degree and fineness and slide 3 are processed with the opposite guideway of upper surface decomposition pressure of static pressure oil pocket, the static pressure oil pocket of slide 3 all is communicated with the flowline of quantitative multi-head pump with the static pressure oil pocket of pressing plate 1, pressing plate 1 provides static pressure oil for respectively the upper and lower surface of guideway with slide 3, for workbench turntable body 5 has increased constraint, make the one degree of freedom on its only remaining gyratory directions, form closed type structure.Because the static pressure area of the static pressure area on the slide 3 on the pressing plate 1, workbench turntable body 5 is subjected to power that makes progress that slide 3 provides and workpiece and pressing plate 1 downward gravity and forms and make a concerted effort like this, the power of coming balance bull gear 4 lower surfaces to make progress, making workbench no matter forward which angle to can both be subjected to evenly and the power of balance, and be used for stoping the random rising of panoramic table, make its levitation height fixing within limits.Because the oil pressure of quantitative static pressure is a dynamic response, so the static pressure up and down that workbench turntable body 5 is subjected to can be regulated automatically according to workpiece weight, make workbench turntable body 5 reach stress balance, and when workbench turntable body 5 bears unbalance loading, because the automatic regulatory function of oil pressure makes it can not be subjected to how many influences.
Establish pressing plate 1 in the closed type static pressure turntable, each pressing plate 1 notch place studs with two copper static pressure pieces 6, with soket head cap screw bull gear 4 is fastened on the workbench simultaneously, and locatees with two straight pins.Pressing plate that designs in the turntable and the static pressure piece that is set in recess can guarantee the positioning accuracy of work table rotation: when bull gear 4 is subjected to the rotating band of drive unit 11 work table rotation, can avoid producing radial load effectively, prevent that gear ring and workbench from forming relative motion, and increased constraint for workbench turntable body 5, reduced its free degree, make the one degree of freedom on its only remaining gyratory directions, form closed type structure.