CN1278891A - Hydraulic machine with radial pistons and variable displacement - Google Patents

Abstract

The hydraulic machine with radial pistons and variable displacement comprises a stator (2) inside which rotates a crankshaft (1) with crank (18) having an eccentric ring (8) which may move in the direction of the throw (V), means for positioning the said eccentric ring, a series of cylinders (4) and corresponding pistons (5) acting on the crank, the means of positioning consisting of a screw (12, 11, 10) positioned on the axis of the throw (V) and coupled to an internal thread (19) fashioned in the throw of the shaft (1); furthermore, the screw is driven externally from the stator by means of a transmission (25) consisting of helical gear wheels (10, 22, 23), with an intermediate wheel with skew axis (22) with respect to the direction of the throw (V) and of the axis of the drive shaft (R). The hydraulic machine may operate both as a motor and as a pump in open or closed circuit.

Description

Have radial piston and variable-displacement hydraulic press

The present invention relates to have radial piston and variable-displacement one hydraulic press, a fluid power motor that promptly has all pistons that radially are arranged on the single crank, in fluid power motor is to have relative stator to be in the oil hydraulic cylinder group of fixed position and to have type in order to a device that changes discharge capacity, and described motor can be used as the pump in closed circuit and the open circuit.

The present situation of this technical field is to comprise that have can be with the fluid power motor of the hydraulic radial cylinder of two or three discharge capacities running.They are equipped with crank and the radially movable eccentric hoop that activates by the double action oil hydraulic cylinder in the crank.Bouncing back fully of described oil hydraulic cylinder is retracted to its minimum degree of eccentricity with crank, thus motor is set in its minimum discharge capacity, and on the other hand, the full extension of crank will extend to its maximum degree of eccentricity, thus motor is set in its maximum discharge capacity.

And, because of discharge capacity only is adjusted to the difficulty that two values are brought, the variable-displacement motor has sizable shortcoming, in addition, because the size and the action thereof of the oil hydraulic cylinder of crank inside, they are difficult to make, because it need or have bigger area than the high pressure of entrance system pressure, are applied to power on the crank with counteracting.

In order to overcome described shortcoming, described crank has been added some device and had two brachiums.

First mechanical device has a member that radially stretches in one of them inside of two cavitys of described internal hydraulic pressure cylinder, to limit its stroke.But because the uncertain location of circumferentially extending member makes it to use, it is insecure that this solution has proved.No longer make.

Second electronic device uses a proportional CVM hydrovalve to control the interior described oil hydraulic cylinder of crank, controls discharge capacity continuously thus in the institute of operation is free.The various reference signals that existence records by suitable sensor: the combination of rotational velocity, inlet pressure, output torque or described parameter, keep a steady state value by making the pressure in the inlet duct, just may obtain so-called " permanent power " torque curve.This system is controlled by computerized electronic equipment, and this electronic equipment makes all variable monitored simultaneously and directly control described Proportional valve.

And, an electronic equipment like this make between the minimum of the discharge capacity that will obtain and maximum value required continuous control become possible in, its manufacture cost is higher, so it only is not suitable for being applied to for example being used for producing the extrusion press of plastic part in some situation that need change discharge capacity constantly.In fact the plastic article extrusion press only in the discharge capacity that needs the regulator solution hydraulic motor when setting up a new production process, before extrusion press must be regulated for production one different part, does not need to change the discharge capacity of motor.If will use on the plastic article extrusion press in order to the described electronic equipment of control displacement variation, cost will be high especially, and not utilize most of particular characteristic of continuous control discharge capacity.

At last, prior art comprises and has variable-displacement radial piston oil hydraulic pump, wherein can obtain the degree of eccentricity by radially mobile external rings, the shoes of each piston externally encircles slip, although oil hydraulic cylinder and live axle rotate in concert, the geometrical shape of the power that produces when exporting torque because of producing, such structure is favourable when being used for pump only, but can not be applied to motor.

With realize overcoming described shortcoming in radial piston fluid power motor/pump in order to the viewpoint of the device that changes discharge capacity, can carry out sizable improvement to the state of related domain.

Can find out from the above, produce the demand that solves this technical problem, promptly develop and have radial piston and variable-displacement one hydraulic press, it has continuous variable displacement, makes economical and is easy to and use.

The present invention has solved above-mentioned technical problem by adopting following scheme, in first embodiment: have radial piston and variable-displacement one hydraulic press, it comprises a stator, and a bent axle that has crank rotates in stator, and crank has the movable eccentric hoop that follows Cheng Fangxiang; Locate the device of described eccentric hoop; A series of oil hydraulic cylinders and corresponding piston, piston acts on the crank by shoes, and by ring constraint center common with it, described positioning device comprises on the axis that is positioned at stroke and be connected in the screw thread of an internal thread that internal thread forms the stroke directions at axle; And described positioning device is equipped with from the outside of stator to the transmission device of screw thread.

In a preferred embodiment, the present invention illustrates: the described transmission device to screw thread comprises gear.

In another preferred embodiment, the present invention illustrates: the direction that described gear has helical ring gear and relative travel and a live axle has a breast wheel of tilt axis.

In another preferred embodiment, the present invention illustrates: the described transmission device from the outside is equipped with a reference disk of indicating crank position and an external control crank that transmission is passed to screw thread.

In another preferred embodiment, the present invention illustrates: the described transmission device that is positioned at the gear downstream comprises an axial pin, and this axial pin is rotatably connected on the one or more sleeve pipes that have the end face tooth, and a locking device is between pivot and sleeve pipe.

In another preferred embodiment, the present invention illustrates: comprise that the mechanism that the described transmission device that is rotatably connected to the axial pin at least one sleeve pipe that has the end face tooth is installed on described axial pin and the described sleeve pipe drives.

In another preferred embodiment, the present invention illustrates: comprise a motor in order to the mechanism that drives the described transmission device that arrives screw thread.

Advantage of the present invention is: have the simple and reliable performance of radial piston fluid power motor manufacturing in order to the spiral gear that changes discharge capacity; When changing the part of producing, the operator of plastic article extrusion press can be adjusted to desired value with the discharge capacity of fluid power motor, with the maximal efficiency that obtains to inject.And, in most of the cases, this means that extrusion press operates fluid power motor under constant pressure, reduced noise level thus greatly, this is owing to the more effective control to the pressure reversal of the fluid in pipe and the oil hydraulic cylinder.And the adjusting of discharge capacity is continuous, and only when needs were locked in external crank on the reference disk, just discharge capacity was regulated in stepping; Driving motor owing to have one, preferably be motor, and therefore the angular orientation of axial pin can adjust the radial position of movable eccentric hoop according to need, with the continuous adjusting of acquisition between the minimum of discharge capacity and maximum value.

At last, same hydraulic press both can be used as motor, also can be used as pump, this is owing to the reversibility of well-known displacement machine, and the possibility that can operate in closed circuit and open circuit, promptly, directly from fuel tank, suck, and do not utilize other auxiliary supply pumps.

In three appended width of cloth figure, only show one embodiment of the present of invention as an example, in the accompanying drawings:

Fig. 1 is the partial, longitudinal cross-sectional that has in order to the one radial piston engine/pump of the device that changes discharge capacity;

Fig. 2 is the sectional view along the amplification of B-B line among Fig. 1, shows the part of the live axle that has control mechanism.

Fig. 3 is the sectional view along A-A line among Fig. 1, has schematically illustrated the radial piston and the crank that have movable eccentric hoop.

Label is as follows: in Fig. 1, and the 1st, be rotatably connected to bent axle on the stator 2 by rolling bearing 3; The 4th, the harmonious oil hydraulic cylinder that oscillatorily is connected in described stator; The 5th, be equipped with the piston of the shoes 6 that hydraulic static hangs, this shoes 6 is connected on the outer cylinder surface 7 of movable eccentric hoop 8; Described piston keeps in touch by means of described shoes and described surperficial 7, and by ring 9 centers common with it; The 10th, spiral gear is fixed with threaded lining 12 with key on its each cylindrical end 11; The 13rd, each internal surface of described eccentric hoop 8, they are parallel to each other and be parallel to axle 1 rotation axis R; The end 11 of described lining 12 and spiral gear contacts with internal surface 13 by means of the pad 14 of different materials; The 15th, connect tooth, it and the bottom 17 of last protuberance 16 contacted described eccentric hoops and live axle 1 between; V is the axis of spiral gear 10, it with the stroke directions of crank 18 and with a guide rail to the described protuberance of axle 1 in the axis of cylinder 4 of dead point PMS and PMI consistent; The 19th, the interior connecting thread of described threaded lining 12, it is made into the stroke of corresponding crank 18; The 20th, be positioned at the slidingsurface of the axle on the described eccentric hoop, and 21 are axle surfaces of 1, gapped between axle 1 and the surface 13 to allow to encircle 8 radial motion.

Also have other following labels: the 22nd, the rectangular spiral gear of described rotation axis V of the rotation axis R of relative motor and spiral gear 10; It rotates in the stroke that forms described crank 18 and is connected on the described gear 10; 23 are mounted in the transmission ratch (pinion) of the band helical tooth on the rotation axis R of motor, and it is connected in described spiral gear 22, and is supported by Babbitt lining 24 in front; 25 is axial pins, and the one side is keyed on the spiral ratch 23, and opposite side is fixed on the external crank 26, and external crank can fold downwards after shaking this mechanism; The 27th, flow to the distributor of the hydraulic fluid of conduit 28, it can rotate in housing 29, and by live axle 1, operate by means of toothed sleeve pipe 30 and puller 31 mode with synchronous rotation, toothed sleeve pipe 30 and puller 31 are connected the opposite end that has spline coupling 32 of axle 1.

Also have some following labels: the 33rd, be connected the toothed indication sleeve pipe on the described distributor 27, and outstanding from the housing 29 of contiguous described external crank 26; The 34th, be keyed on the reference disk on the described indication sleeve pipe 33, the instantaneous position of indication sleeve pipe 33 indication cranks 18; 35 is coaxial supporting members, and at the infall of the outer wall of the housing 29 of distributor 27, it has the Sealing in order to the hydraulic fluid that keeps described sleeve pipe 33 and described axial pin 25.

Also have following labels at last: in Fig. 2, the 36th, in order to connect the wall of described eccentric hoop 8 and respective surfaces 20; The 37th, the hole of traversing crank 18, described spiral gear 22 is positioned at crank 18 and is supported by bearing 38, and described hole is clogged by stopper 39; C is the range ability along the longitudinal axis V that crosses ring 8; In Fig. 3, E is the degree of eccentricity of crank 18, and it is the degree of eccentricity I sum on described distance C and surface 20.

The operation that has radial piston and variable-displacement hydraulic machinery is carried out in the following manner.In operation, secured adjusted to the position of movable eccentric hoop 8, also have distributor 27 and live axle 1 to be synchronized with the movement, be instructed to that sleeve pipe 33 usefulness keys are fixed and the reference disk 34 that draws is also set for and is synchronized with the movement, external crank 26 directly is keyed on the axial pin 25, and pivot 25 is keyed on again on the power screw ratch 23.Based on the constancy of the position of described ring 8, can accurately carry out the motion of one between external crank and the reference disk, and by means of the position of reference disk indication crank 18.In practice, external crank 26 is in the folding position, and dish 34 is protected by a not shown overcoat, to avoid that the user is caused accident.

In needs, the user stops motor and rotates external crank 26 operations with hand, with the degree of eccentricity of the described movable eccentric hoop 8 of random change, changes displacement value thus.The motion that is applied to external crank 26 is sent to power screw ratch 23 by means of axial pin 25, exists to be applied under the situation of the normal resistive torque on the live axle 1, and transmission ratch 23 rotates and rotation is passed to spiral gear 22.Described spiral gear passes motion to the spiral gear 10 that is connected again, in this way, the axial rotation of external crank is converted to the rotation of spiral gear, and, cause movable eccentric hoop 8 to move to desired value along the axis V of described gear 10 by means of be fixed in the two threaded linings 12 that its end 11 connects internal thread 19 again with key.

The surface 13 that pad 14 by different materials comes retaining ring 8 contacts with all metallicity between the end 11 of lining 12 and spiral gear, with the weldering knot of avoiding causing because of creep " sintering ".

In practice, the exact position of the impossible described ring 8 of visual verification, still, by calculating the revolution of external crank 26, perhaps part is changeed, and simultaneously with reference to reference disk 34, just can accurately control the displacement value of the motor of wanting.

The hydraulic press that has in order to the spiral gear that changes discharge capacity can assemble remote controllers, it preferably is stepping type, to replace having the described external crank of motor, in operating usually, this controller and live axle 1 rotate in concert, and in the adjustment process of discharge capacity, it is set described axial pin 25 relative to indication sleeve pipe 33 for rotates, as the above narration that is used for manually changing, the result is that relative drive shaft 1 rotates.

Because motor contacts by slip ring and powers, so the rotation of axial pin 25 relative drive shafts can be carried out with the hydraulic press in the motion.An available fluid power motor that operates with a rotation pipeline is replaced the motor that control axial pin 25 rotates.

Test shows that the helical ring gear of ratch 23 and gear 22 and 10 preferably tilts at 45.

And, for between adjusting color screw gear 10 and 22 and the structural play between the latter and the ratch 23, the structure of the gear ring of spiral gear 22 and spiral ratch 23 provides along the axial tapering of the installation direction in their each pedestals, so the axial adjustment of spiral gear 22 and ratch 23 can be eliminated said play.

There is shown and have the radial piston fluid power motor/pump that oscillating cylinder does not promptly have connecting rod.The present invention is applied to have with also can having identical effect and is fixed to the cylinder on the stator and has in the fluid power motor/pump of the connecting rod between piston and crank 18.

In practice, if material, size and details of operation with shown in those are different, but should be equal to technically do not break away from judicial confining spectrum of the present invention shown in those contents.

But to drive the method for discharge capacity spiral gearing, variation is feasible.Therefore, though not good enough a little, in order to change the purpose of discharge capacity, when can only being arranged in structure, rotation maybe when changing the purposes of motor, undertaken by the technology intervention, it is equipped with the device that changes discharge capacity according to the present invention, sets with predetermined fixed displacement, to avoid distorting of access by unauthorized persons.The rotation of outside bent axle 26 can not have ground, neutral position to take place, and the screw of controlling movable eccentric hoop 8 can only be with machine adjustments to maximum or minimum injection rate.

At last, reference disk 34 can be subdivided in order to toothed all parts of described external crank 26 to be installed, accurately to rotate all parts by a circle again.In order to obtain stepless in relative rotation variation, the available clutch mechanism of the part between described reference disk 34 and external crank 26 is realized, eliminates the needs to above-mentioned each predetermined segmentation part thus, and allows continuously changing of discharge capacity.

At last, even not good enough a little, the driving of axial pin 25 can activate by differential gearing or epicyclic gear train with the hydraulic press in the motion, and these devices or train are connected to described pivot and sleeve pipe 33, and in its outside manually-operable; The rotation of live axle 1 provides the driving force of relative angle between change pivot and the sleeve pipe (reciprocal angle), and the use of at least one intermediate gear can realize the counter-rotating that drives.Available friction wheel is replaced the effect that gear is realized described gearing.

Claims (14)

1. have radial piston and variable-displacement hydraulic press, it comprises a stator (2), and a bent axle (1) that has crank (18) rotates in stator, and crank (18) has the movable eccentric hoop (8) that follows Cheng Fangxiang (V); Locate the device of described eccentric hoop; A series of oil hydraulic cylinders (4) and corresponding piston (5), piston (5) acts on the crank by shoes (6), and constraint center common with it by ring (9), it is characterized in that: described positioning device comprises on the axis that is positioned at stroke (V) and is connected in the screw thread of an internal thread (19) (12,11,10) that internal thread (19) is formed on the stroke directions of axle (1); And described positioning device is equipped with from the outside of stator to the transmission device (25) of screw thread.

2. as the described hydraulic press of above claim, it is characterized in that: the described transmission device to screw thread comprises gear (10,22,23).

3. as the described hydraulic press of above claim, it is characterized in that: the direction that described gear has helical ring gear and relative travel (V) and a live axle (R) has a breast wheel (22) of tilt axis.

4. as the described hydraulic press of above claim, it is characterized in that: the angle of inclination of the spiral of gear ring is 45 degree.

5. as a described hydraulic press in the claim 1,2,3, it is characterized in that: the transmission device from the outside is equipped with a reference disk (34) of indicating crank position and an external control crank (26) that transmission is passed to screw thread.

6. as a described hydraulic press in the claim 2,3, it is characterized in that: the described transmission device that is positioned at the gear downstream comprises an axial pin, this axial pin is connected in the one or more sleeve pipes (33,30) that have the end face tooth rotationally, and a locking device (25,34) is between pivot and sleeve pipe.

7. as a described hydraulic press in the claim 3,4, it is characterized in that: if described gear is installed on their each pedestal, the gear ring of gear (22,23) is tapered vertically.

8. as a described hydraulic press in the claim 1,2,3, it is characterized in that: the mechanism that the described transmission device that comprises an axial pin (25) that is connected at least one sleeve pipe that has end face tooth (33) rotationally is installed on described axial pin (25) and the described sleeve pipe (33) drives.

9. as the described hydraulic press of above claim, it is characterized in that: the mechanism that drives the described transmission device that arrives screw thread (12) is a motor.

10. as the described hydraulic press of above claim, it is characterized in that: this motor is a stepping type.

11. as the described hydraulic press of above claim 8, it is characterized in that: the mechanism that drives the described transmission device that arrives screw thread (12) is a fluid power motor.

12. as a described hydraulic press in the above claim 6,8, it is characterized in that: described axial pin (25) and the respective sleeve that has an end face tooth (33) are positioned at the avris of distributor (27).

A 13. as described hydraulic press in the above claim, it is characterized in that: screw thread (12) contacts with each surface (13) of described movable eccentric hoop (8) by pad, and the material of pad is different with the material of the gear (10,11) of ring, screw thread and/or support thread.

14. hydraulic press as claimed in claim 8 is characterized in that: described gear comprises and is connected in axial pin (25) and sleeve pipe (33) and from its manually operated differential gear of outside housing be used to drive at least one intermediate gear of reversing.

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