阅读说明：本技术 一种电液执行器中的摆动液压缸 (Swing hydraulic cylinder in electro-hydraulic actuator ) 是由 刘贵明 张健 贾明旺 于 2020-12-09 设计创作，主要内容包括：本发明公开了一种电液执行器中的摆动液压缸,包括：齿轮箱,齿轮箱中设有带键孔的齿轮,齿轮箱的两侧分别安装有缸筒,每个缸筒中均设有两个活塞和齿条,两个齿条均与齿轮相啮合,每个缸筒的两端上分别设有油孔,每个齿条的背面均设有支撑轴瓦,每个缸筒内腔的两端底部上均设有缓冲套,各个活塞的外端上均设有缓冲凸台,每个缓冲套上均设有阻尼孔和畅流孔,每个缸筒中的齿条和两个活塞均不连接固定；在每个活塞的侧壁上均设置有纳污环；支撑轴瓦的外圈表面上设有盲孔,缸筒的侧壁上设置有沉头螺纹孔,沉头螺纹孔中旋入有调节螺栓,调节螺栓的内端插入至盲孔中；每个缸筒中均嵌设有两个导向环。上述的摆动液压缸具有较长的使用寿命。(The invention discloses a swing hydraulic cylinder in an electro-hydraulic actuator, which comprises: the gear box is internally provided with a gear with a keyhole, two sides of the gear box are respectively provided with a cylinder barrel, each cylinder barrel is internally provided with two pistons and two racks, the two racks are meshed with the gear, two ends of each cylinder barrel are respectively provided with an oil hole, the back of each rack is provided with a supporting bearing bush, the bottoms of two ends of an inner cavity of each cylinder barrel are respectively provided with a buffer sleeve, the outer end of each piston is provided with a buffer boss, each buffer sleeve is provided with a damping hole and a smooth hole, and the rack and the two pistons in each cylinder barrel are not fixedly connected; a dirt containing ring is arranged on the side wall of each piston; the surface of the outer ring of the supporting bearing bush is provided with a blind hole, the side wall of the cylinder barrel is provided with a countersunk threaded hole, an adjusting bolt is screwed in the countersunk threaded hole, and the inner end of the adjusting bolt is inserted into the blind hole; two guide rings are embedded in each cylinder barrel. The swing hydraulic cylinder has long service life.)

1. An oscillating hydraulic cylinder in an electro-hydraulic actuator, comprising: a gear box, a gear with a keyhole is arranged in the gear box, the keyhole can be inserted by a valve shaft, so that the gear can control the valve by driving the valve shaft to rotate, a cylinder is respectively arranged at the upper part and the lower part of the gear box, the middle parts of the two cylinders are communicated with the gear box, each cylinder is provided with two pistons and a cylindrical rack positioned between the two pistons, each piston is provided with a sealing ring capable of sealing a gap between the piston and the cylinder, the two racks are respectively engaged with the gear through the communication part of the cylinder and the gear box, two ends of each cylinder are respectively provided with an oil hole communicated with an inner cavity of the cylinder, pressure oil can drive the piston at the end of the cylinder to push the rack and the other piston to move towards the other end of the cylinder after being introduced into one end of the cylinder through the oil holes, so that the rack can drive the gear to rotate, Another piston can be with the oilhole extrusion cylinder of the oil in the cylinder other end through its place end, two oilholes on every cylinder all lead to oil in turn like this and make two racks do the reciprocating motion opposite in direction after just can drive gear positive and negative rotation, all be provided with a support axle bush between the back of every rack and cylinder, support the axle bush and adjust the meshing clearance between rack and the gear through pressing the rack, its characterized in that: the bottom of two ends of each cylinder barrel cavity is provided with a buffer sleeve facing a piston, the outer ends of two pistons in each cylinder barrel are respectively provided with a buffer boss facing the buffer sleeve at the end where the two pistons are located, each buffer boss is formed by coaxially connecting a circular table section and a cylindrical section located on the inner side of the circular table section, the small end of the circular table section is located on the outer side, the diameter of the cylindrical section is equal to the diameter of the large end of the circular table section, the cylindrical section is fixed with the piston, each buffer sleeve is provided with a damping hole and an open flow hole, one port of the damping hole is located on the end face of the buffer sleeve and communicated with the cylinder barrel cavity, the other port of the damping hole is communicated with an oil hole at the end of the damping hole through a pipeline with a one-way throttle valve, the one-way throttle valve can throttle oil flowing from the damping hole to the oil hole, and one port of the open flow hole is located on the inner ring, the other port of the smooth flow hole is communicated with the oil hole at the end of the smooth flow hole through a pipeline, an inner ring sealing ring positioned at the inner side of the smooth flow hole is arranged on the side wall of the inner ring of each buffer sleeve, when the piston moves to the end part of the cylinder barrel, the buffer boss on the piston can be inserted into the corresponding buffer sleeve, so that the circular platform section on the buffer boss can gradually reduce the through-flow section of the inner ring of the buffer sleeve along with the insertion, thereby reducing the oil flowing out from the smooth flow hole, playing a role of buffering the speed of the piston, when the cylindrical section on the buffer boss is inserted into the buffer sleeve, the inner ring sealing ring can seal the gap between the cylindrical section and the buffer sleeve, so that the oil cannot flow out through the smooth flow hole, and the oil can only flow out from the damping hole, thus limiting the flow of the oil through the one-way throttle valve and playing a role of buffering the speed of the, the speed of the piston speed reduction can be adjusted; the rack in each cylinder barrel and the two pistons are not fixedly connected; an annular accommodating groove is formed in the side wall of each piston, a dirt accommodating ring for cleaning impurities is placed in each accommodating groove, and the dirt accommodating ring is located on the inner side of a sealing ring on the piston; the support bearing bush is an arc-shaped spherical iron bush, a blind hole is formed in the surface of the outer ring of the support bearing bush, a countersunk threaded hole is formed in the side wall of the cylinder barrel, an adjusting bolt is screwed into the countersunk threaded hole from outside to inside, and the inner end of the adjusting bolt is inserted into the blind hole and presses the support bearing bush; two guide rings which are sleeved on the rack and are respectively positioned on two sides of the gear are embedded in each cylinder barrel, the guide rings can guide the rack and can prevent the end part of the rack from scraping the inner wall of the cylinder barrel when the rack is flexibly deformed.

2. The electro-hydraulic actuator swing cylinder of claim 1, wherein: the one-way throttle valve is provided with a manual knob positioned on the outer side, and the throttle opening of the one-way throttle valve can be conveniently adjusted by rotating the manual knob.

3. The electro-hydraulic actuator swing cylinder of claim 1, wherein: the width of the guide ring is not less than twice the pitch on the rack.

4. The electro-hydraulic actuator swing cylinder of claim 1, wherein: the blind hole is located at the center of the supporting bearing bush.

5. The electro-hydraulic actuator swing cylinder of claim 1, wherein: and a sealing ring is arranged between the buffer sleeve and the side wall of the cylinder barrel.

Technical Field

The invention relates to the field of electro-hydraulic actuators, in particular to a swing hydraulic cylinder in an electro-hydraulic actuator.

Background

The principle of the swing hydraulic cylinder is that reciprocating motion of a piston drives a gear through a rack to be converted into forward and reverse swing rotation of the gear, and meanwhile, thrust of the piston is converted into output torque of the gear. However, the conventional swing hydraulic cylinder generally has structural defects, so that the service life of the swing hydraulic cylinder is not long.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the swing hydraulic cylinder in the electro-hydraulic actuator has long service life.

In order to solve the problems, the technical scheme adopted by the invention is as follows: an oscillating hydraulic cylinder in an electro-hydraulic actuator, comprising: a gear box, a gear with a keyhole is arranged in the gear box, the keyhole can be inserted by a valve shaft, so that the gear can control the valve by driving the valve shaft to rotate, a cylinder is respectively arranged at the upper part and the lower part of the gear box, the middle parts of the two cylinders are communicated with the gear box, each cylinder is provided with two pistons and a cylindrical rack positioned between the two pistons, each piston is provided with a sealing ring capable of sealing a gap between the piston and the cylinder, the two racks are respectively engaged with the gear through the communication part of the cylinder and the gear box, two ends of each cylinder are respectively provided with an oil hole communicated with an inner cavity of the cylinder, pressure oil can drive the piston at the end of the cylinder to push the rack and the other piston to move towards the other end of the cylinder after being introduced into one end of the cylinder through the oil holes, so that the rack can drive the gear to rotate, Another piston can be with the oilhole extrusion cylinder of the oil in the cylinder other end through its place end, two oilholes on every cylinder all lead to oil in turn like this and make two racks do the reciprocating motion opposite in direction after just can drive gear positive and negative rotation, all be provided with a support axle bush between the back of every rack and cylinder, support the axle bush and adjust the meshing clearance between rack and the gear through pressing the rack, its characterized in that: the bottom of two ends of each cylinder barrel cavity is provided with a buffer sleeve facing a piston, the outer ends of two pistons in each cylinder barrel are respectively provided with a buffer boss facing the buffer sleeve at the end where the two pistons are located, each buffer boss is formed by coaxially connecting a circular table section and a cylindrical section located on the inner side of the circular table section, the small end of the circular table section is located on the outer side, the diameter of the cylindrical section is equal to the diameter of the large end of the circular table section, the cylindrical section is fixed with the piston, each buffer sleeve is provided with a damping hole and an open flow hole, one port of the damping hole is located on the end face of the buffer sleeve and communicated with the cylinder barrel cavity, the other port of the damping hole is communicated with an oil hole at the end of the damping hole through a pipeline with a one-way throttle valve, the one-way throttle valve can throttle oil flowing from the damping hole to the oil hole, and one port of the open flow hole is located on the inner ring, the other port of the smooth flow hole is communicated with the oil hole at the end of the smooth flow hole through a pipeline, an inner ring sealing ring positioned at the inner side of the smooth flow hole is arranged on the side wall of the inner ring of each buffer sleeve, when the piston moves to the end part of the cylinder barrel, the buffer boss on the piston can be inserted into the corresponding buffer sleeve, so that the circular platform section on the buffer boss can gradually reduce the through-flow section of the inner ring of the buffer sleeve along with the insertion, thereby reducing the oil flowing out from the smooth flow hole, playing a role of buffering the speed of the piston, when the cylindrical section on the buffer boss is inserted into the buffer sleeve, the inner ring sealing ring can seal the gap between the cylindrical section and the buffer sleeve, so that the oil cannot flow out through the smooth flow hole, and the oil can only flow out from the damping hole, thus limiting the flow of the oil through the one-way throttle valve and playing a role of buffering the speed of the, the speed of the piston speed reduction can be adjusted; the rack in each cylinder barrel and the two pistons are not fixedly connected; an annular accommodating groove is formed in the side wall of each piston, a dirt accommodating ring for cleaning impurities is placed in each accommodating groove, and the dirt accommodating ring is located on the inner side of a sealing ring on the piston; the support bearing bush is an arc-shaped spherical iron bush, a blind hole is formed in the surface of the outer ring of the support bearing bush, a countersunk threaded hole is formed in the side wall of the cylinder barrel, an adjusting bolt is screwed into the countersunk threaded hole from outside to inside, and the inner end of the adjusting bolt is inserted into the blind hole and presses the support bearing bush; two guide rings which are sleeved on the rack and are respectively positioned on two sides of the gear are embedded in each cylinder barrel, the guide rings can guide the rack and can prevent the end part of the rack from scraping the inner wall of the cylinder barrel when the rack is flexibly deformed.

Further, the swing hydraulic cylinder in the electro-hydraulic actuator, wherein: the one-way throttle valve is provided with a manual knob positioned on the outer side, and the throttle opening of the one-way throttle valve can be conveniently adjusted by rotating the manual knob.

Further, the swing hydraulic cylinder in the electro-hydraulic actuator, wherein: the width of the guide ring is not less than twice the pitch on the rack.

Further, the swing hydraulic cylinder in the electro-hydraulic actuator, wherein: the blind hole is located at the center of the supporting bearing bush.

Further, the swing hydraulic cylinder in the electro-hydraulic actuator, wherein: and a sealing ring is arranged between the buffer sleeve and the side wall of the cylinder barrel.

The invention has the advantages that: the swing hydraulic cylinder can be buffered when the piston moves to the end part of the cylinder barrel due to the addition of the adjustable buffer mechanism, so that the service life of the swing hydraulic cylinder can be prolonged, and the speed of the piston which is reduced when the piston is buffered can be adjusted, so that the swing hydraulic cylinder can be more suitable for occasions with high-speed rotation and working conditions with adjustable end buffering requirements, in addition, the swing hydraulic cylinder is further greatly prolonged because the rack and the two pistons are not fixedly connected, a dirt receiving ring is arranged on the piston, the support bearing bush is arranged as a spherical iron bush, and an adjusting bolt and a guide ring are additionally arranged.

Drawings

Fig. 1 is a schematic structural diagram of a swing hydraulic cylinder in an electro-hydraulic actuator according to the present invention.

Detailed Description

The present invention will be described in further detail below with reference to specific embodiments and the attached drawings.

As shown in fig. 1, an oscillating hydraulic cylinder in an electro-hydraulic actuator includes: a gear box 1, a gear 2 with a keyhole is arranged in the gear box 1, the keyhole can be inserted by a valve shaft, so that the gear 2 can control the valve by driving the valve shaft to rotate, a cylinder 3 is respectively arranged at the upper part and the lower part of the gear box 1, the middle parts of the two cylinders 3 are communicated with the gear box 1, two pistons 4 and a cylindrical rack 5 positioned between the two pistons 4 are arranged in each cylinder 3, a sealing ring capable of sealing a gap between the piston 4 and the cylinder 3 is arranged on each piston 4, the two racks 5 are engaged with the gear 2 for transmission through the communication part of the cylinder 3 and the gear box 1, oil holes 6 communicated with the inner cavity of the cylinder 3 are respectively arranged at the two ends of each cylinder 3, pressure oil is introduced into one end of the cylinder 3 through the oil holes 6 and then can drive the piston 4 at the end to push the rack 5 and the other piston 4 to move towards the other end of the cylinder 3, so that the rack 5 can drive the gear 2 to rotate, the other piston 4 can press oil in the other end of the cylinder 3 out of the cylinder 3 through the oil hole 6 in the end where the other piston is located, thus the two oil holes 6 on each cylinder 3 are alternately filled with oil to drive the gear 2 to rotate forward and backward after the two racks 5 do reciprocating motion in opposite directions, a supporting bearing bush 7 is arranged between the back surface of each rack 5 and the cylinder 3, the supporting bearing bush 7 adjusts the meshing gap between the rack 5 and the gear 2 by pressing the rack 5, the bottom parts of the two ends of the inner cavity of each cylinder 3 are respectively provided with a buffer sleeve 7 facing the piston 4, the outer ends of the two pistons 4 in each cylinder 3 are respectively provided with a buffer boss 8 facing the buffer sleeve 7 in the end where the two pistons are located, each buffer boss 8 is formed by coaxially connecting a circular platform section 81 and a cylindrical section 82 located on the inner side of the circular platform section, the small end of the circular platform section 81 is positioned at the outer side, the diameter of the cylindrical section 82 is equal to the diameter of the large end of the circular platform section 81, the cylindrical section 82 is fixed with the piston 4, each buffer sleeve 7 is provided with a damping hole 71 and an open flow hole 72, one port of the damping hole 71 is positioned on the end surface of the buffer sleeve 7 and is communicated with the inner cavity of the cylinder barrel 3, the other port of the damping hole 71 is communicated with the oil hole 6 at the end of the damping hole through a pipeline with a one-way throttle valve 9, the one-way throttle valve 9 can throttle oil flowing from the damping hole 71 to the oil hole 6, one port of the open flow hole 72 is positioned on the inner ring side wall of the buffer sleeve 7 and is communicated with the inner cavity of the cylinder barrel 3, the other port of the open flow hole 72 is communicated with the oil hole 6 at the end of the open flow hole through a pipeline, an inner ring sealing ring 73 positioned at the inner ring of the open flow hole 72, the buffering boss 8 on the piston 4 can be inserted into the corresponding buffering sleeve 7, so that the circular platform section 81 on the buffering boss 8 can gradually reduce the through-flow section of the inner ring of the buffering sleeve 7 along with the insertion, and the oil flowing out of the smooth flow hole 72 can be reduced, so that the buffering effect of reducing the speed of the piston 4 can be achieved, when the cylindrical section 82 on the buffering boss 8 is inserted into the buffering sleeve 7, the inner sealing ring 73 can seal the gap between the cylindrical section 82 and the buffering sleeve 7, so that the oil cannot flow out through the smooth flow hole 72, and the oil can only flow out of the damping hole 71, so that the flow of the oil can be limited through the one-way throttle valve 9, the buffering effect of reducing the speed of the piston 4 can be achieved, and the opening throttling of the one-way throttle valve 9 can be adjusted, so that the speed of the piston 4 can be reduced, namely;

the rack 5 and the two pistons 4 in each cylinder barrel 3 are not fixedly connected; an annular accommodating groove is formed in the side wall of each piston 4, a dirt accommodating ring 642 for cleaning impurities is placed in each accommodating groove, and the dirt accommodating ring 642 is located on the inner side of a sealing ring on the piston 4; the supporting bearing bush 7 is an arc-shaped ball iron bush, the ball iron has good self-lubricating performance and higher hardness than copper, a blind hole 671 is arranged on the surface of the outer ring of the supporting bearing bush 7, the blind hole 671 is positioned at the center of the supporting bearing bush 7, a countersunk head threaded hole 631 is arranged on the side wall of the cylinder barrel 3, an adjusting bolt 632 is screwed into the countersunk head threaded hole 631 from outside to inside, and the inner end of the adjusting bolt 632 is inserted into the blind hole 671 and presses the supporting bearing bush 7; two guide rings 68 which are sleeved on the rack 5 and are respectively positioned at two sides of the gear 2 are embedded in each cylinder 3, and the guide rings 68 can guide the rack 5 and can prevent the end part of the rack 5 from scraping the inner wall of the cylinder 3 when the rack 5 is flexibly deformed.

In the present embodiment, the flow opening hole 72 is an L-shaped hole, which is relatively easy to machine. The one-way throttle valve 9 is provided with a manual knob 91 positioned at the outer side, and the throttle opening of the one-way throttle valve 9 can be conveniently adjusted by rotating the manual knob 91. And a sealing ring is arranged between the buffer sleeve 7 and the side wall of the cylinder barrel 3, so that oil leakage can be prevented.

In this embodiment, the guide ring 68 is a ductile iron ring, and the ductile iron has good self-lubricating property and high hardness. The width a of the guide ring 68 is not less than twice the pitch on the toothed rack 5, which is provided for better guidance.

The gear can provide a large radial force for the rack in the rotating process, the rack and the two pistons in the conventional swing hydraulic cylinder are usually connected and fixed, so that the radial force can be transmitted to the pistons, the sealing element on the pistons can be quickly abraded, the function of the oil cylinder is failed, and in order to avoid the problem, the piston and the rack are not connected and fixed, the piston and the rack are integrally separated, the sealing structure of the piston is not influenced when the rack is subjected to the radial force, and the design can prolong the service life of the sealing element, so that the service life of the swing hydraulic cylinder can be prolonged.

Scrap iron is generated due to tooth surface friction between the gear and the rack, the scrap iron is brought into the cylinder barrel through the rack and falls on the inner wall of the cylinder barrel, and when a piston passes through the position, the damage of a piston sealing piece or the pulling damage of the inner wall of the cylinder barrel can be caused, so that the failure of the swing hydraulic cylinder is caused.

The supporting bearing bush in the conventional swing hydraulic cylinder is usually a copper bush, copper has a self-lubricating function but is soft, the requirement on the roughness of a rack is high, if the roughness of the rack is high, the abrasion of the supporting bearing bush is aggravated, so that the supporting bearing bush cannot well press the rack, the meshing gap between the rack and a gear is enlarged, the tooth surfaces of the rack and the gear are seriously abraded, and the service life of the swing hydraulic cylinder is influenced; when the supporting bearing bush is worn, the supporting bearing bush can be attached to the pressing rack again by rotating the adjusting bolt downwards.

The gear can apply a large radial force to the rack in the rotating process, so that the rack can generate flexible deformation, after the flexible deformation, two ends of the rack can easily scrape the inner wall of the cylinder barrel, and further the swing hydraulic cylinder is out of work.