CN203239674U

CN203239674U - Servo hydraulic cylinder

Info

Publication number: CN203239674U
Application number: CN 201320112433
Authority: CN
Inventors: 蔡杲星; 郑雄胜
Original assignee: Zhejiang Ocean University ZJOU
Current assignee: Zhejiang Ocean University ZJOU
Priority date: 2013-03-12
Filing date: 2013-03-12
Publication date: 2013-10-16
Anticipated expiration: 2023-03-12

Abstract

The utility model discloses a servo hydraulic cylinder which comprises a cylinder barrel. A piston driven by a servo motor through a transmission mechanism is arranged inside the cylinder barrel. The side walls of the two end portions of the cylinder barrel are provided with an oil inlet and an oil return opening respectively. The servo hydraulic cylinder is characterized in that a center hole in the axial direction is formed inside the tail portion of the piston, first small holes which are symmetric about the center hole are formed in the tail end of the piston, second small holes which are symmetric about the center hole and are communicated with the oil return opening are formed in the side wall of the middle of the piston, a spiral groove is formed in the surface of the inner side wall of the tail portion of the cylinder barrel, the first small holes are communicated with the center hole and the spiral groove, and the first small holes and the spiral groove form a half bridge with variable resistances. The servo hydraulic cylinder is simple in structure, convenient to install and good in anti-pollution performance, has the advantages of being small in corner, capable of achieving continuous control, high in response speed, good in speed stability, high in control precision and the like, and can be widely applied in automation devices such as various mechanical arms, robots, metallurgical devices, machine tools and engineering machines.

Description

Servo hydraulic cylinder

Technical field

The utility model relates to a kind of servo hydraulic cylinder, especially a kind of spiral servo oil hydraulic cylinder with dual free dimension.

Background technique

Servo hydraulic cylinder is widely used in the automation equipments such as various mechanism hands, robot, metallurgical equipment, lathe, engineering machinery as a kind of typical electrohydraulic integration control unit.Traditional servo hydraulic cylinder is made of stepper motor, hydraulic efficiency slide valve, oil hydraulic cylinder and mechanical feedback mechanism etc., pulse control signal is inputted by stepper motor, the displacement of piston is by its inner ball screw feedback, and stepper motor turns to corner corresponding to the movement direction of piston in conjunction with displacement.This servo hydraulic cylinder complex structure, the ball screw cost is high, the servovalve required precision is high, have discrete steps, speed of response is slow, precision is low, resistance tocrocking is poor, price, etc. shortcoming.

The model utility content

Technical problem to be solved in the utility model provides a kind of simple in structure, easy for installation, servo hydraulic cylinder that precision is high.

The utility model solves the problems of the technologies described above the technological scheme that adopts: a kind of servo hydraulic cylinder, comprise cylinder barrel, be provided with the piston that is driven by driving mechanism by actuating motor in the described cylinder barrel, offer respectively filler opening and return opening on the two end part sidewall of described cylinder barrel, it is characterized in that, be provided with axial center hole in the afterbody of described piston, the tail end of described piston has relative center hole and is symmetrical aperture I, offer relatively described center hole on the sidewall at described piston middle part and be the symmetrical aperture II that is communicated with described return opening, offer spiral chute on the interior side-wall surface of described cylinder barrel afterbody, described aperture I is communicated with center hole and spiral chute, and described aperture I and spiral chute consist of the adjustable resistance half-bridge.

The head of described piston also is provided with grating scale and photoelectric encoder, the signal that can detect the axial of piston and rotate, and this signal is transferred to control module, the digital pulse signal that sends with it compares, thereby consisted of the feedback of closed-loop structure, can compensate factors such as system temperature, pressure load, internal leakage and dead bands.

Described driving mechanism comprises the small gear that is connected with the output shaft of described actuating motor, be set in described piston crown and gearwheel described pinion, the both sides of described gearwheel are respectively equipped with top board and the press table fixing with described piston, described top board and press table clamp described gearwheel, the rotation of actuating motor is by the transmission of small gear and gearwheel, thus the drive piston rotation.

Compared with prior art, the utility model has the advantage of: simple in structure, easy for installation, antifouling property is good, has corner little, the energy continuous control, response is fast, speed stability is good and the control accuracy advantages of higher, can be widely used in the automation equipments such as various mechanism hands, robot, metallurgical equipment, lathe, engineering machinery; Adopt the dual free dimension screw mechanism, namely piston has around the rotary freedom of axis with along the one-movement-freedom-degree of axis, and the sealing when having avoided the piston rotation has guaranteed again the accurate transmission that rotatablely moves simultaneously.

Description of drawings

Fig. 1 is the front view of oil hydraulic cylinder of the present utility model;

Fig. 2 is that the A-A of Fig. 1 is to sectional view.

Embodiment

Embodiment is described in further detail the utility model below in conjunction with accompanying drawing.

Referring to Fig. 1 and Fig. 2, a kind of servo hydraulic cylinder, be applied to electrohydraulic servo-controlling system or proportion servo-control system, comprise cylinder barrel 1, be provided with piston 2 in the cylinder barrel 1, piston 2 extends the head of cylinder barrel 1, the tail end of piston 2 is fixing with the flange plate 3 that is positioned at cylinder barrel 1 tail end, flange plate 3 is fixing with cylinder barrel 1 by screw 31, and flange plate 3 extends between part in the cylinder barrel 1 and the cylinder barrel 1 and is provided with O RunddichtringO I 32, to prevent hydraulic fluid leak.

The head of cylinder barrel 1 is fixed with upper cylinder cover 4, and cylinder barrel 1 is played effect fixing, that seal and lead.Actuating motor 5 is fixing with upper cylinder cover 4, and the joint is provided with packing ring 52, drives piston 2 by driving mechanism and rotates, and is respectively equipped with O RunddichtringO II 11 and O RunddichtringO III 12 between upper cylinder cover 4 and cylinder barrel 1, the piston 2.Driving mechanism comprises, the small gear 51 that the output shaft of actuating motor 5 connects, piston 2 stretch out the head of cylinder barrel 1 sheathed with gearwheels 22 small gear 51 engagements, the both sides of gearwheel 22 are respectively equipped with top board 23 and the press table 24 of fixing with piston 2, top board 23 and the locking of press table 24 usefulness fastening screw trip bolts can be clamped gearwheel 22, thereby the rotation of gearwheel 22 can drive top board 23 and press table 24, the i.e. rotation of piston 2.

The head of piston 2 also is provided with grating scale 27 and photoelectric encoder (not shown), and grating scale 27 is for detection of the axial displacement of piston 2, and photoelectric encoder is for detection of the rotation angle of piston 2.

Be provided with axial cylindrical center bore 25 in the afterbody of piston 2, the tail end of piston 2 has relative center hole 25 and is two symmetrical aperture I 29, offer relative center hole 25 on the sidewall at piston 2 middle parts and be two symmetrical aperture II 26, offer leg-of-mutton spiral chute 28 on the interior side-wall surface of cylinder barrel 1 afterbody, aperture I 29 is communicated with center hole 25, spiral chute 28.Offer arc filler opening 13 on the sidewall of cylinder barrel 1 afterbody, be communicated with piston 2, offer arc return opening 14 on the sidewall of cylinder barrel 1 head, be communicated with aperture II 26.

During work, the control module of servo-control system is sent digital pulse signal to actuating motor 5, actuating motor 5 work are passed through driving mechanism so that piston 2 rotates, lap area between aperture I 29 and the spiral chute 28 reduces, high pressure oil enters into the hyperbaric chamber (being seen as the loculus of piston 2 right-hand members from Fig. 2) of piston 2 from filler opening 13, triangle spiral chute 28 by offering on cylinder barrel 1 inner wall surface and aperture I 29 enter the active chamber (being seen as the large chamber of piston 2 left ends from Fig. 2) of piston 2, again by aperture I 29, leave cylinder barrel 1 from return opening 14 behind the center hole 25 and behind the aperture 26, pressure in the active chamber is increased, broken original equilibrium relation, piston 2 moves right, lap area between aperture I 29 and the spiral chute 28 is increased, until return to original value, pressure in the active chamber also is decreased to former equilibrium value, equate with the downward thrust of hyperbaric chamber and external load, piston 2 reaches a kind of equilibrium relation again, and vice versa.Like this, spiral chute 28 consists of the adjustable resistance half-bridge with aperture I 29, makes the lap area change between aperture I 29 and the spiral chute 28, thereby changes the pressure in the active chamber, the certain corner of actuating motor 5 inputs, and piston 2 just produces corresponding displacement.

Simultaneously, the signal that grating scale 27 and photoelectric encoder can detect the axial of piston 2 and rotate, and this signal is transferred to control module, the digital pulse signal that sends with it compares, thereby consisted of the feedback of closed-loop structure, can compensate factors such as system temperature, pressure load, internal leakage and dead bands.

The above only is preferred implementation of the present utility model; should be pointed out that for the ordinary skill in the art, do not breaking away under the principle prerequisite of the present utility model; can also make various deformation and improvement, this also should be considered as protection domain of the present utility model.

Claims

1. servo hydraulic cylinder, comprise cylinder barrel (1), be provided with the piston (2) that is driven by driving mechanism by actuating motor (5) in the described cylinder barrel (1), offer respectively filler opening (13) and return opening (14) on the two end part sidewall of described cylinder barrel (1), it is characterized in that, be provided with axial center hole (25) in the afterbody of described piston (2), the tail end of described piston (2) has relative center hole (25) and is symmetrical aperture I (29), offer relatively described center hole (25) on the sidewall at described piston (2) middle part and be the symmetrical aperture II (26) that is communicated with described return opening (14), offer spiral chute (28) on the interior side-wall surface of described cylinder barrel (1) afterbody, described aperture I (29) is communicated with center hole (25) and spiral chute (28), and described aperture I (29) consists of the adjustable resistance half-bridge with spiral chute (28).

2. servo hydraulic cylinder as claimed in claim 1 is characterized in that, the head of described piston (2) also is provided with grating scale (27) and photoelectric encoder.

3. servo hydraulic cylinder as claimed in claim 1 or 2, it is characterized in that, described driving mechanism comprises the small gear (51) that is connected with the output shaft of described actuating motor (5), that be set in described piston (2) head and gearwheel (22) described small gear (51) engagement, the both sides of described gearwheel (22) are respectively equipped with top board (23) and the press table (24) fixing with described piston (2), and described top board (23) and press table (24) clamp described gearwheel (22).