CN203656263U - Electro-hydraulic servo valve provided with movable gear rack - Google Patents

Electro-hydraulic servo valve provided with movable gear rack Download PDF

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Publication number
CN203656263U
CN203656263U CN201320596552.4U CN201320596552U CN203656263U CN 203656263 U CN203656263 U CN 203656263U CN 201320596552 U CN201320596552 U CN 201320596552U CN 203656263 U CN203656263 U CN 203656263U
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CN
China
Prior art keywords
hydraulic fluid
fluid port
tooth bar
valve pocket
spool
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CN201320596552.4U
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Chinese (zh)
Inventor
蒋林
吴若麟
***
胡国
郑洁
曾良才
孙杉
梅鹏
胡琪
晏晚君
胡金
郑翠
郑开柳
肖俊
刘晓磊
陈新元
傅连东
赵慧
刘白雁
雷斌
曾镛
许仁波
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Wuhan University of Science and Engineering WUSE
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Wuhan University of Science and Engineering WUSE
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Priority to CN201320596552.4U priority Critical patent/CN203656263U/en
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Publication of CN203656263U publication Critical patent/CN203656263U/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Abstract

An electro-hydraulic servo valve provided with a movable gear rack comprises a valve sleeve (17) as well as a slide valve sleeve (5) and a stepping motor (9) which are arranged above the valve sleeve (17), wherein a valve core gear rack (13) is arranged in the middle of the inside of the valve sleeve (17), the lower end tooth surface of the valve core gear rack (13) is meshed with a gear oscillating bar (15), a feedback bracket (16) is arranged on the upper end surface of the valve core gear rack (13), and the upper end of the feedback bracket (16) is connected with the slide valve sleeve (5) through a feedback pin (19). The electro-hydraulic servo valve has the characteristics of simple structure, easiness in processing, good self-servo performance, large oscillating angle of the oscillating rod, large output torque, high response speed and control accuracy and the like.

Description

The portable electrohydraulic control of a kind of tooth bar
Technical field
The utility model relates to electrohydraulic control technical field, specifically the portable electrohydraulic control of a kind of tooth bar.
Background technique
Hydraulic transmission is that motor is combined with hydraulics from servo techniques, utilizes advantage separately, directly drives spool that valve port is opened by the little moment of motor, allows high pressure oil act on valve body, and then obtains large output torque.Hydraulic transmission is the core parts in hydraulic control system from servo techniques, it has high, the swift feature of precision, in high-precision electro-mechanical system, the airborne drive system of Aero-Space, large-scale experiment equipment, have a wide range of applications, thereby obtain domestic and international scientific and technical personnel's concern.
At present, general electro-hydraulic position servo system, by using electrohydraulic control, is converted to powerful hydraulic power by low power electrical signal, thereby has realized the servocontrol of some heavy duty equipments.But output is larger push-pull effort, and can not output torque.
" a kind of double-leaf hydraulic pressure is from servo oscillating cylinder " (application number is 201310064890.8) patented technology has overcome above-mentioned existing problem, it is, by electrohydraulic control and swing hydraulic pressure cylinder, low power electrical signal is converted to powerful hydraulic power, and then output torque; This servovalve is using hydraulic oil as working medium, and servo blind area is little and be easy to the feature of controlling, but exists element structure complexity, oil duct to be difficult to the problems such as processing, running shaft deflection angle is little, assembling needs are very high degree of adaptability.
Model utility content
The utility model is for the deficiencies in the prior art, proposed that a kind of tooth bar movable type, output torque are large, simple in structure, oil duct is easy to processing,, fast response time good from servo performance, the portable electrohydraulic control of tooth bar that control accuracy is high.
The portable electrohydraulic control of a kind of tooth bar, comprise valve pocket 17 and the slide valve buckle 5, the stepper motor 9 that are located at valve pocket 17 tops, position, the interior middle of described valve pocket 17 is provided with spool tooth bar 13, the spool tooth bar 13 lower end flank of tooth are meshed with gear fork 15, spool tooth bar 13 upper-end surfaces are provided with feedback support 16, and feedback support 16 upper ends are sold 19 with slide valve buckle 5 by feedback and are connected.
Described valve pocket 17, comprises left cylinder cap 1, right cylinder cap 12, offers respectively left and right hydraulic fluid port 2,11 on valve pocket 17, and valve pocket 17 inside are cylindrical cavity 25, and the internal diameter of cylindrical cavity 25 is identical with the nominal size of the left and right boss external diameter of spool tooth bar 13; The middle part of valve pocket 17 offers respectively hole 24, lower hole 26, and feedback support 16 passes hole 24 and is connected with slide valve buckle 5, and gear fork 15 stretches out outside valve pocket 17 through lower hole 26.
Described slide valve buckle 5 is connected with valve pocket 17 by guiding valve holder 4,7, slide valve buckle 5 comprises front slide valve cover 3, rear slide valve cover 8, on slide valve buckle 5, offer successively from left to right the first hydraulic fluid port 30, the second hydraulic fluid port 31, the 3rd hydraulic fluid port 32, the 4th hydraulic fluid port 33 and the 5th hydraulic fluid port 34, in slide valve buckle 5, establish sliding spool 6, described sliding spool 6 is provided with left boss 36 and right boss 37, the initial position of left boss 36 and right boss 37 is corresponding with the second hydraulic fluid port 31 and the 4th hydraulic fluid port 33 of slide valve buckle 5 respectively, and the right-hand member straight-tooth 38 of sliding spool 6 and the axle of stepper motor 9 are meshed.
Described gear fork 15 is arranged on gear shaft 21, and fixing by gear pin 20 between gear shaft 21 and gear fork 15, gear shaft 21 two ends are provided with gear shaft holder 14.
On the left and right boss of described spool tooth bar 13, all have seal groove 27, in seal groove 27, be provided with the seal ring that cross section is rectangle.
Described left cylinder cap 1, right cylinder cap 12 be concentric left end and the right-hand member that is arranged on valve pocket 17 respectively, and between left cylinder cap 1 and valve pocket 17, right cylinder cap 12 and valve pocket 17, respectively having a cross section is circular seal ring 35.
Described the second hydraulic fluid port 31 communicates with the right chamber of valve pocket 17, and the 4th hydraulic fluid port 33 communicates with the left chamber of valve pocket 17, and the first hydraulic fluid port 30 and the 5th hydraulic fluid port 34 are return opening.
The utility model is achieved in that
Owing to adopting technique scheme, when stepper motor of the present utility model rotates to an angle, can be by the logical high pressure oil of the 3rd hydraulic fluid port to slide valve buckle, high pressure oil enters respectively the Huo You chamber, left chamber of valve pocket through the hydraulic fluid port on slide valve buckle, at this moment left and right two chamber mineralization pressures are poor, just promoting spool tooth bar moves, spool tooth bar moves and drives feedback support-moving, in the time that feedback support-moving just blocks the second hydraulic fluid port and the 3rd hydraulic fluid port to two boss, now sliding spool is in meta, the just stop motion of spool tooth bar.
Sliding spool starts to be positioned at meta most, be also its left and right boss just block slide valve buckle second, the 4th hydraulic fluid port; When it is moved to the left, second, third hydraulic fluid port communicates, now in left position; When it moves right, the 3rd, the 4th hydraulic fluid port communicates, now in right position; The second hydraulic fluid port communicates with the right chamber of valve pocket, and the 4th hydraulic fluid port communicates with the left chamber of valve pocket, first and the 5th hydraulic fluid port be return opening.
In the time that stepper motor clockwise rotates several angle, sliding spool is just moved to the left, now, sliding spool just becomes left position by meta, and high pressure oil is entered by the 3rd hydraulic fluid port, enter the right chamber of valve pocket by the second hydraulic fluid port again, now chamber, valve pocket left and right mineralization pressure is poor, and spool tooth bar is moved to the left, and spool tooth bar moves to left, and with feeding back, support moves to left and gear fork is rotated counterclockwise, feedback support moves to left and moves to left with slide valve buckle, finally makes sliding spool in meta.
In the time that stepper motor rotates counterclockwise several angle, sliding spool just moves right, now, sliding spool just becomes right position by meta, and high pressure oil is entered by the 3rd hydraulic fluid port, enter the left chamber of valve pocket by the 4th hydraulic fluid port again, now chamber, valve pocket left and right mineralization pressure is poor, and spool tooth bar is moved right, and spool tooth bar moves to right, and with feeding back, support moves to right and gear fork turns clockwise, feedback support moves to right and moves to right with slide valve buckle, finally makes sliding spool in meta.
The advantage of the portable electrohydraulic control of the utility model tooth bar is:
1) there is a spool tooth bar valve pocket of the present utility model middle, valve pocket inside is divided into two oil pockets in left and right by spool tooth bar left and right end, the oil channel structure of the portable electrohydraulic control of whole tooth bar is simple, there is no complicated internal oil channel, left and right cylinder cap, slide valve buckle, these designs of part of sliding spool are also fairly simple in addition, be easy to processing, therefore the machining accuracy of part easily ensures;
2) when stepper motor of the present utility model rotates to an angle, can be by leading to high pressure oil to slide valve buckle the 3rd hydraulic fluid port, high pressure oil enters respectively the Huo You chamber, left chamber of valve pocket through the hydraulic fluid port on slide valve buckle, at this moment left and right two chamber mineralization pressures are poor, just promoting spool tooth bar moves, spool tooth bar moves and drives feedback support-moving, in the time that feedback support-moving just blocks the second hydraulic fluid port and the 4th hydraulic fluid port to two boss, now sliding spool is in meta, the just stop motion of spool tooth bar, thereby complete whole from servo process, as can be seen here, the portable electrohydraulic control of tooth bar of the present utility model is better from servo performance,
3) sliding spool of the present utility model is after stepper motor rotates to an angle, its position can become left position or right position from meta, now high pressure oil enters the Huo You chamber, left chamber of valve pocket, and valve pocket left and right two chamber mineralization pressures are poor, under the effect of pressure difference, spool tooth bar can move to the left or to the right, the movement of spool tooth bar will make gear fork swing counterclockwise or clockwise several angle, and then output torque, from analyzing, its swing arm pendulum angle is large, and output torque is large;
4) when stepper motor of the present utility model rotates to an angle, start from meta becomes left position or right position from sliding spool, to the motion to the left or to the right under the poor effect of valve pocket left and right two cavity pressures of spool tooth bar, get back to meta to final sliding spool again, this is whole just completes soon from servo process very much, as can be seen here, the portable electrohydraulic control fast response time of tooth bar, control accuracy are high.
Brief description of the drawings
Fig. 1 is structural representation of the present utility model;
Fig. 2 is the A-A generalized section of Fig. 1;
Fig. 3 is the plan structure schematic diagram of valve pocket;
Fig. 4 is the B-B generalized section of Fig. 3;
Fig. 5 is the structural representation of spool tooth bar;
Fig. 6 is the C-C generalized section of Fig. 5;
Fig. 7 is the structural representation of right cylinder cap;
Fig. 8 is the D-D generalized section of Fig. 7;
Fig. 9 is the structural representation of gear fork;
Figure 10 is the structural representation of slide valve buckle;
Figure 11 is the structural representation of sliding spool.
In figure, 1 is left cylinder cap, 2, 11 is hydraulic fluid port, 3 is front slide valve cover, 4, 7 is guiding valve holder, 5 is slide valve buckle, 6 is sliding spool, 8 is rear slide valve cover, 9 is stepper motor, 10 is stepper motor seat, 12 is right cylinder cap, 13 is spool tooth bar, 14 is gear shaft holder, 15 is gear fork, 16 is feedback support, 17 is valve pocket, 18 is guiding valve holder bolt, 19 is feedback pin, 20 is gear pin, 21 is gear shaft, 22 is articulating pin, 23 is tapped hole, 24 is upper hole, 25 is cylindrical cavity, 26 is lower hole, 27 is seal groove, 28, 29 is screw, 30 is the first hydraulic fluid port, 31 is the second hydraulic fluid port, 32 is the 3rd hydraulic fluid port, 33 is the 4th hydraulic fluid port, 34 is the 5th hydraulic fluid port, 35 is seal ring, 36 is left boss, 37 is right boss, 38 is right-hand member straight-tooth.
Embodiment
Below in conjunction with accompanying drawing, the utility model is further described: as shown in Fig. 1-11, the portable electrohydraulic control of a kind of tooth bar, comprises right cylinder cap 1, hydraulic fluid port 2, front slide valve cover 3, guiding valve holder 4, slide valve buckle 5, sliding spool 6, guiding valve holder 7, rear slide valve cover 8, stepper motor 9, stepper motor seat 10, hydraulic fluid port 11, right cylinder cap 12, spool tooth bar 13, gear shaft holder 14, gear fork 15, feedback support 16, valve pocket 17.
As depicted in figs. 1 and 2, left cylinder cap 1, right cylinder cap 12 is concentric left end and the right-hand member that is arranged on valve pocket 17 respectively, left cylinder cap 1 and valve pocket 17, between right cylinder cap 12 and valve pocket 17, respectively there is a seal ring 30 as shown in Figure 8, the concentric middle that is arranged on valve pocket 17 of spool tooth bar 13, the spool tooth bar 13 lower end flank of tooth are connected with gear fork 15, there is a feedback support 16 spool tooth bar 13 upper-end surfaces, feedback support 16 upper ends are connected with slide valve buckle 5 use feedback pins 19, front slide valve cover 3, rear slide valve cover 8 is concentric left end and the right-hand member that is arranged on slide valve buckle 5 respectively, guiding valve holder 4 and guiding valve holder 7 are arranged on the positive top of valve pocket 17, and for supporting fixing slide valve buckle 5, concentric slide valve buckle 5 inside that are arranged on of sliding spool 6, its right-hand member is connected with stepper motor 9, stepper motor 9 is arranged on stepper motor seat 10, stepper motor seat 10 is arranged on valve pocket 17.
As shown in Figure 1, Figure 3 and Figure 4, have a cylindrical cavity 25 in described valve pocket 1, cylindrical cavity 25 internal diameters are identical with the nominal size of spool tooth bar 13 left and right boss external diameters; Hydraulic fluid port 2, hydraulic fluid port 11 and upper hole 24 are arranged at the positive top of valve pocket 17, and hole 26 is once arranged at the positive bottom of valve pocket 17.
There is a spool tooth bar 13 valve pocket 17 centers, the spool tooth bar 13 lower end flank of tooth are connected with gear fork 15, gear fork 15 is arranged in the lower hole 26 of valve pocket 17, and spool tooth bar 13 upper-end surfaces are connected with feedback support 16, and feedback support 16 is arranged in the upper hole 24 of valve pocket 17.Valve pocket 17 upper ends are connected with guiding valve holder 4, guiding valve holder 7 and stepper motor seat 10 by tapped hole 23 use bolts.
As shown in Fig. 1, Fig. 5 and Fig. 6, spool tooth bar 13 is connected by screw 28 use bolts with feedback support 16, on spool tooth bar 13 left and right end boss, has seal groove 27, and left and right seal groove 27 is interior is all equipped with the seal ring that cross section is rectangle.
As shown in Fig. 1, Fig. 7 and Fig. 8, between described left cylinder cap 1 and valve pocket 17, right cylinder cap 12 and valve pocket 17, respectively having a cross section is circular seal ring 35, and left cylinder cap 1, right cylinder cap 12 are connected with valve pocket 17 by screw 29 use bolts respectively.
As shown in Fig. 1 and Fig. 9, gear fork 15 is arranged on gear shaft 21, and its upper end flank of tooth is meshed with spool tooth bar 13, and fixing by gear pin 20 between gear shaft 21 and gear fork 15, gear shaft 21 two ends are connected with gear shaft holder 14.
As shown in Fig. 1 and Figure 10, five hydraulic fluid ports are arranged at the positive top of described slide valve buckle 5, are respectively the first hydraulic fluid port 30, the second hydraulic fluid port 31, the 3rd hydraulic fluid port 32, the 4th hydraulic fluid port 33 and the 5th hydraulic fluid port 34.
As shown in Fig. 1 and Figure 11, described sliding spool 6 is concentric to be arranged in slide valve buckle 5, its right-hand member straight-tooth 38 is meshed with stepper motor 9 shaft end gears, in the time that stepper motor 9 is worked, sliding spool 6 side-to-side movements, have left boss 36, right boss 37 on sliding spool 6, under original state, sliding spool 6 is in meta, and now left boss 36 is just blocked slide valve buckle the second hydraulic fluid port 31, and right boss 37 is just blocked slide valve buckle the 4th hydraulic fluid port 33.

Claims (7)

1. the portable electrohydraulic control of tooth bar, comprise valve pocket (17) and be located at valve pocket (17) top slide valve buckle (5), stepper motor (9), it is characterized in that: (13) (17) described valve pocket be provided with spool tooth bar in position, interior middle, (15) the spool tooth bar (13) lower end flank of tooth is meshed with gear fork, (16) spool tooth bar (13) upper-end surface is provided with feedback support, and (19) (5) (16) feedback support sold and be connected by feedback with slide valve buckle in upper end.
2. the portable electrohydraulic control of tooth bar as claimed in claim 1, it is characterized in that: described valve pocket (17), comprise left cylinder cap (1), right cylinder cap (12), (17) valve pocket is gone up and is offered respectively left and right hydraulic fluid port (2,11), valve pocket (17) inside is cylindrical cavity (25), and the internal diameter of cylindrical cavity (25) is identical with the nominal size of spool tooth bar left and right boss external diameter (13); Valve pocket middle part (17) offers respectively hole (24), lower hole (26), and (16) feedback support passes hole (24) and be (5) connected with slide valve buckle, gear fork (15) pass lower hole (26) stretch out valve pocket (17) outside.
3. the portable electrohydraulic control of tooth bar as claimed in claim 1, it is characterized in that: described slide valve buckle is (5) by guiding valve holder (4, 7) be (17) connected with valve pocket, (3) (5) slide valve buckle comprise front slide valve cover, rear slide valve cover (8), (5) slide valve buckle is gone up and is offered successively from left to right the first hydraulic fluid port (30), the second hydraulic fluid port (31), the 3rd hydraulic fluid port (32), the 4th hydraulic fluid port (33) and the 5th hydraulic fluid port (34), (6) slide valve buckle establishes sliding spool in (5), (6) sliding spool is provided with left boss (36) and right boss (37), the initial position of left boss (36) and right boss (37) is corresponding with slide valve buckle the second hydraulic fluid port (31) and the 4th hydraulic fluid port (33) (5) respectively, sliding spool right-hand member straight-tooth (38) and stepper motor axle (9) is (6) meshed.
4. the portable electrohydraulic control of tooth bar as claimed in claim 1, it is characterized in that: (15) described gear fork is arranged on gear shaft (21), gear shaft (21) and gear fork are (20) fixing by gear pin between (15), and (14) gear shaft (21) two ends are provided with gear shaft holder.
5. the portable electrohydraulic control of tooth bar as claimed in claim 2, is characterized in that: on described spool tooth bar left and right boss (13), all have seal groove (27), be provided with the seal ring that cross section is rectangle in seal groove (27).
6. the portable electrohydraulic control of tooth bar as claimed in claim 2, it is characterized in that: described left cylinder cap (1), (12) concentric valve pocket left end and the right-hand member (17) that be arranged on respectively of right cylinder cap, left cylinder cap (1) and valve pocket (17), right cylinder cap (12) and valve pocket respectively to have a cross section between be (17) circular seal ring (35).
7. the portable electrohydraulic control of tooth bar as claimed in claim 3, it is characterized in that: described the second hydraulic fluid port (31) communicates with valve pocket right chamber (17), the 4th hydraulic fluid port (33) communicates with valve pocket left chamber (17), and the first hydraulic fluid port (30) and the 5th hydraulic fluid port (34) are return opening.
CN201320596552.4U 2013-09-26 2013-09-26 Electro-hydraulic servo valve provided with movable gear rack Expired - Fee Related CN203656263U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201320596552.4U CN203656263U (en) 2013-09-26 2013-09-26 Electro-hydraulic servo valve provided with movable gear rack

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201320596552.4U CN203656263U (en) 2013-09-26 2013-09-26 Electro-hydraulic servo valve provided with movable gear rack

Publications (1)

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CN203656263U true CN203656263U (en) 2014-06-18

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103452951A (en) * 2013-09-26 2013-12-18 武汉科技大学 Pendulum-lever type self-servo hydraulic cylinder
CN108674116A (en) * 2018-05-08 2018-10-19 山河智能特种装备有限公司 Two-chamber floating cylinder and its simple pendulum arm suspension of application and suspension adjusting method
CN112112864A (en) * 2020-10-12 2020-12-22 辽宁工程技术大学 Load pressure control type digital fluid cylinder

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103452951A (en) * 2013-09-26 2013-12-18 武汉科技大学 Pendulum-lever type self-servo hydraulic cylinder
CN103452951B (en) * 2013-09-26 2016-05-25 武汉科技大学 A kind of oscillating rod type is from servo hydraulic cylinder
CN108674116A (en) * 2018-05-08 2018-10-19 山河智能特种装备有限公司 Two-chamber floating cylinder and its simple pendulum arm suspension of application and suspension adjusting method
CN108674116B (en) * 2018-05-08 2024-05-17 山河智能特种装备有限公司 Double-cavity floating cylinder, single swing arm suspension system applied by same and suspension adjusting method
CN112112864A (en) * 2020-10-12 2020-12-22 辽宁工程技术大学 Load pressure control type digital fluid cylinder

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C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20140618

Termination date: 20170926

CF01 Termination of patent right due to non-payment of annual fee