KR200221797Y1 - stepless cushion type hydraulic cylinder - Google Patents

Abstract

The present invention relates to an endless buffered hydraulic cylinder which minimizes or prevents the shock caused by the hydraulic piston at the reciprocating motion point and the end point by an endless buffering method to minimize or prevent the damage caused by the impact.

To this end, the present invention is a hydraulic or pneumatic actuator using a piston (3) reciprocating by the pressure difference between the inlet and outlet side of the hydraulic cylinder (1), the piston (3) is the rod cover 10 or the head cover (12) As it is inserted into the collecting holes 14 and 16 respectively recessed in the bottom surface, the forward and backward side cushion part for gradually reducing the flow passage 11 of the hydraulic oil moving to the forward and backward side ports 20 and 22 by the piston 3. An endless shock absorbing hydraulic cylinder provided with (7, 9) is provided.

Therefore, according to the present invention, it is possible to reduce the unit cost by adopting the stepless deceleration cushion parts 7 and 9 instead of the conventional cushion control valve and the cushion hole, and to minimize the shock value during the first deceleration and stoppage, Any object that employs a cylinder can be smoothly transferred.

Description

Stepless cushion type hydraulic cylinder

The present invention relates to a hydraulic cylinder, and more particularly, when the conventional hydraulic cylinder is stopped at the forward or reverse stage, the impact caused by the hydraulic piston at the cushioning point and the end point is minimized or prevented by the stepless buffer method. It relates to an endless buffer hydraulic cylinder to prevent all problems caused by.

In general, the actuator transfers the object connected to the end of the piston rod by moving the piston from the high pressure side to the low pressure side by the differential pressure on the left and right sides of the piston through the intermediate piston, for example, for the short-distance transfer of a certain object or for the transfer requiring a large force. Hydraulic cylinders have been widely used.

As such, the hydraulic cylinder used for conveying a certain object has a piston for converting the hydraulic cars of the front and rear ports into which the hydraulic flows in and out, and a piston rod for transmitting force to the conveying object, which supports and smoothly operates the hydraulic cylinder. Consists of a body and a cover, and at the same time, a cushioning device is installed to alleviate the shock generated when the target is suddenly stopped while transferring the object at a high speed.

As shown in FIG. 1, a hydraulic cylinder having a conventional typical cushioning device for reducing the shock generated when the hydraulic cylinder suddenly stops while transferring a certain object at high speed is illustrated.

In FIG. 1, reference numeral 101 denotes a tube, 102 a rod, 103 a piston, 104 a rod cover, 105 a head cover, 106 a cushioning ring, 107 a cushion control valve, 108 a rocker, and 109 a cushion flow path.

As shown in FIG. 1, in the conventional hydraulic cylinder, when the pressure oil introduced to the forward side or the reverse side pushes the piston 103, the piston is pushed to the opposite side and the outlet flow is blocked by the cushioning 106. Flows through the small diameter cushion flow path 109 in which the cushion valve is installed, and is proportional to the difference between the area of the original outlet flow path and the area of the small diameter cushion flow path 109 in which the cushion valve 107 is installed. The piston 103 is moved at a low speed, the impact occurs by the difference in the moving speed. At this time, by adjusting the diameter of the cushion passage 109 by the cushion valve 107, the buffer force can be adjusted.

However, in the conventional hydraulic cylinder having the above cushioning device, the shock absorbing effect can be expected to some extent by reducing the speed once at one point, that is, reducing the speed from one point without the piston traveling to the end. The difference in speed is large, and since the first stage cushion is conveyed at a constant speed adjusted by the cushion valve, the shock is divided into two parts, and still some degree of impact is applied to the ends.

In addition, adjusting the cushion valve to the lowest level (or significant low speed) to reduce the impact of the last stop stopper reduces the impact on the stopper at stop, but rather increases the first-stage cushion impact and increases the number of stops due to the low speed travel of the piston. It takes time.

Therefore, due to the primary first cushion shock, the machine moves and the level of the machine is distorted, which may cause the degree of the machine to be disturbed, resulting in machining failure or permanent deformation of the machine. In addition, various accidents may be caused by loosening of fastening bolts. In addition, the impact on the stopper may cause damage to the stopper due to the impact on the stopper, and may cause a safety accident.

In addition, adjusting the cushion valve to the lowest value (or a considerable low speed) in order to reduce the impact value at rest will result in a larger impact value of the first stage cushion. There was also a problem that the cost increases because it takes more time to perform a job or work.

Until now, the above-mentioned single-stage cushioning hydraulic cylinders have been used in many machines or apparatuses, but in practice, there have been many invisible economic losses because they have been used to reduce the rapid feed speed or adjust the buffering force so that problems are not revealed in the short term.

The present invention is devised to solve the problems of the prior art as described above, by minimizing or zeroing the impact of the cushion start time and the stop time, which occurs when the hydraulic cylinder is stopped at both ends after rapid transfer. Hydraulic cylinder equipped with an endless cushioning device that can dramatically reduce the quality of the machined parts, permanent deformation of the machine, and the occurrence of safety accidents by eliminating problems such as breakage of the front and rear diagnosis stopper and mechanical level disturbance caused by the impact. The purpose is to provide.

1 is a longitudinal sectional view of a conventional general hydraulic cylinder.

2 is a longitudinal sectional view of a hydraulic cylinder according to the present invention.

Figure 3 is a longitudinal sectional view and left and right side views of the slot-type removable cushion portion of the hydraulic cylinder according to the present invention.

4 is a partial side view showing the operating state of the cushion unit shown in FIG. 3 along the line AA ′ of FIG. 2.

5 to 16 are each a longitudinal sectional view and a left and right side view showing another embodiment of the hydraulic cylinder cushion unit according to the present invention,

Figure 5 is a tapered removable, Figure 6 is a hybrid removable, Figure 7 is a triangular removable, Figures 8 and 9 through-hole removable, Figure 10 is a slot type, Figure 11 is a tapered type, Figure 12 is a mixed type 13 to 16 are diagrams each showing a piston detachable cushion unit.

17 is a longitudinal sectional view of a hydraulic cylinder to which a hydraulic cylinder cushion unit according to another embodiment of the present invention is applied.

18 is a longitudinal sectional view of a hydraulic cylinder to which a hydraulic cylinder cushion unit according to another embodiment of the present invention is applied.

<Explanation of symbols for main parts of the drawings>

1,201,301: Hydraulic cylinder 2: Tube

3: piston 5: piston rod

7,9: forward and backward side cushion portion 10: rod cover

11: cushion euro 12: head cover

13,15: forward and backward boss portion 14,16: forward and backward engagement hole

17,19: Forward and backward cushion bush 20,22: Forward and backward port

21: threaded portion 23: double nut

25: tap hole 27: bolt

329: protrusion 330,331: cushion control valve

The present invention is to achieve the above object, in the hydraulic or pneumatic actuator using a piston reciprocating by the pressure difference between the inlet and outlet side of the hydraulic cylinder, the piston is inserted into each of the collecting hole in the rod cover or head cover bottom As a result, there is provided an endless cushioning hydraulic cylinder having a forward and backward cushion portion to gradually reduce the flow path of the hydraulic oil moving to the forward and backward port by the piston.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Endless buffered hydraulic cylinder according to the present invention is a tube (2), the tube (2), which constitutes a large body like the hydraulic cylinder widely used in general hydraulic actuators, as shown by reference number 1 in FIG. The rod cover 10 and the head cover 12 inserted into and mounted on the forward and backward side opening of the hydraulic piston 3 reciprocating between the two covers 10 and 12, and a piston coupled to the piston 3. It consists of the rod 5.

The inside of the tube 2 is filled with the hydraulic fluid flowing in or out through the forward port 20 of the rod cover 10, or the hydraulic fluid flowing in or out through the reverse port 22 of the head cover 12, the hydraulic oil Is introduced or discharged by an external hydraulic pump or the like. In addition, the front and rear bosses 13 and 15 are provided on both side surfaces of the piston 3, and the bosses 13 and 13 of the piston 3 are disposed on the bottom surface of the head cover 12 and the rod cover 10, that is, the inner surface. The collecting holes 14 and 16 into which the cushion portions 7 and 9 formed at 15 are inserted at the starting point or the end point of the reciprocating motion are recessed.

At this time, the tube 2 is made of general steel, and supports the cover (10, 12) of both ends and at the same time serves as a guide of the piston (3). In addition, the piston (3) is along the inner circumferential surface of the tube (2) in the discharge or inflow direction at a speed proportional to the force proportional to the pressure difference between the inlet and outlet side of the hydraulic oil flowing from the forward and backward side Move. This means that any object connected to the piston rod 2 moves at the same force and speed as above.

In this way, the piston 3 moving at a constant speed by the force acting on the piston forward and backward side has the rod cover 10 and the head cover 12 when the cushions 7 and 9 formed on the piston 3 move forward and backward. From the moment it is inserted into the collecting holes 14 and 16 which are precisely processed to the same diameter as the outer diameter of the piston 3 on the bottom, it is decelerated steplessly, that is, at a constant reduction ratio. 3) The cross-sectional area gradually decreases as the distance increases from 3). As the material of the cushion parts 7, 9, the material is the same as the piston 3, the rod cover 10, and the head cover 12. Otherwise, it is preferable to apply a material having a similar coefficient of thermal expansion. Further, the processing of the cushion portions 7 and 9 can be performed by turning, end mill, wire cutting, grinding, or the like.

Each of the cushion portions 7 and 9 is composed of the following two types, as shown in FIGS. 3 and 5 to 9, and the cushion bushes 17 and 19 at the forward and backward boss portions 13 and 15 on both sides of the piston. 10 may be detachably mounted, or the cushion bush may be integrally formed on the outer circumferential surfaces of the front and rear bosses 13 and 15 as illustrated in FIGS. 10 to 12.

Here, as shown in FIGS. 3 and 5 to 9, the cushion bushes 17 and 19 are detachably fitted to the front and rear boss parts 13 and 15 of the piston 3, and thus the cushion parts 7 and 9 are coupled to each other. In the case of forming the embodiment, as shown, it can be divided into the following six types, first, the cushion portion (7, 9) shown in Figures 2 and 3 is a piston (3) on the outer peripheral surface of each cushion bush (17, 19) At least one cushion passage 11 in the form of an inclined slot having a radial cross section in which the inner diameter surface is tapered so as to be farther away from the radial length, that is, the depth thereof is radially formed. Accordingly, the cushion sections 7 and 9 start to be inserted into the collecting holes 14 and 16 on the forward and backward sides, and each of the inclined slots has a rectangular cross-sectional cushion channel formed together with the inlet edge portions of the collecting holes 14 and 16 ( 11) to decrease gradually.

Likewise, the cushion parts 7 and 9 shown in FIG. 5 are tapered in the shape of a truncated cone so that the radius of the cushion bushes 17 and 19 itself becomes farther away from the piston 3. An annular cushion flow path 11 formed between the outer circumferential surface of the cushion bushes 17 and 19 and the inner circumferential surface of the collecting holes 14 and 16 as (7, 9) is inserted into the collecting holes 14 and 16 on the forward and backward sides. Is gradually reduced.

In addition, the cushion bushes 17 and 19 are inclined slot-shaped cushion flow paths which are deepened in a direction away from the piston 3 by mixing the cushion flow paths 11 of FIGS. 3 and 5 as shown in FIG. 6. (11) formed radially, but only a portion of the outer end of the cushion bush (17, 19) tapered in the form of a chamfered shape when the insertion hole (14, 16) when inserted into the ring-shaped cushion in which a plurality of protrusions extend inwardly The flow path 11 can also be formed.

In another embodiment, the cushion portions 7 and 9 shown in FIG. 7 are formed by a slot in a flat triangular shape in which the side wall surface becomes wider as the distance from the piston 3 increases, and the width in the radial direction is kept intact. The cushion passage 11 formed is composed of one or more radially processed cushion bushes 17 and 19.

Finally, the cushion parts 7 and 9 shown in FIGS. 8 and 9 penetrate the plurality of through holes 35 in the radial direction to the cushion bushes 17 and 19 mounted on the forward and backward boss parts 13 and 15. One or more cushion flow paths 11 are formed radially and processed. In FIG. 8, the width of the through-hole 35 is maintained constant regardless of the distance from the piston 3 as shown in FIG. As the distance from 3) increases, the diameter of the through-hole 35 is increased. In the case of FIG. 9, the diameter of the through-hole 35 remains the same, but as the distance from the piston 3 increases, the number increases. In this case, the through holes 35 in each case are connected to the forward and backward side collecting holes 14 and 16 by a distribution hole 39 penetrating in the longitudinal direction at the lower end thereof.

As shown in FIGS. 10 to 12, the cushioning parts 7 and 9 of the hydraulic cylinder according to another exemplary embodiment of the present invention have different forward and backward boss parts 13 and 15 themselves from FIG. 3. It is formed by processing in the form of the cushion bush (17, 19) shown in Figure 10, in the case of Fig. 10 in the inclined slot-shaped cushion flow path 11 shown in Figure 3 on the outer peripheral surface of each boss portion (13, 15) Directly processed, the cushion portions 7 and 9 of FIG. 11 are formed by tapering the outer peripheral surfaces of the boss portions 13 and 15 to be inclined in the form of FIG. 5, and the cushion portions 7 and 9 of FIG. It forms in the form which combined the cushion parts 7, and 9 of FIG. In addition, although not shown, a cushion channel of the type shown in FIGS. 7 to 9 may be formed directly on the bosses 13 and 15.

As a further variant, the hydraulic cylinder 1 according to the present invention can be configured separately from the piston rod 5, as shown in FIGS. 13 to 16. Thus, regardless of whether the advancing side cushion portion 7 is formed by the removable cushion bush 17 as shown in Figs. 13 and 14 or the boss portion 13 as shown in Figs. 15 and 16, the piston 3 And the reverse side cushion bush 19 are detachably coupled to the outer circumferential surface of the reverse side boss portion 15 extending from the forward side boss portion 13, respectively, and the reverse side cushion portion 9 shown in FIGS. 13 and 15. Is a double nut 23 fastened to the threaded portion 21 extending from the reverse side boss portion 15, so that the reverse side cushion portion 9 shown in Figs. 14 and 16 is the center of the boss portion 15. The piston 27 and the reverse cushion bush 19 fitted to the outer circumferential surface of the reverse side boss portion 15 are fixed by bolts 27 and washers 28 inserted into and fastened to the tab holes 25 processed therein. .

Another embodiment of a hydraulic cylinder according to the present invention is shown at 201 in FIG. 17.

As shown in FIG. 17, the hydraulic cylinder 201 has a similar configuration to the hydraulic cylinder 1, but the cushion portions 207 and 209 for decelerating the piston 203 at the starting point or the end point of the reciprocating motion have a rod cover of the cylinder ( There is a difference formed in the inner circumferential surfaces of the front and rear advancing side collecting holes 214 and 216 processed on the bottom surface of the 210 and the head cover 212.

Here, the cushion portions 207 and 209 can be detachably mounted on the inner circumferential surface of the collecting holes 214 and 216 as shown in FIG. 17, but are not directly shown, but are integrally directly integrated into the inner circumferential surfaces of the collecting holes 214 and 216. You can also process.

At this time, the cushion portions 207 and 209 are radially deeper toward the forward and backward side ports 220 and 222 as shown in FIG. 3 on the inner circumferential surfaces of the cushion bushes 217 and 219 or the inner circumferential surfaces of the collecting holes 214 and 216, as shown in FIG. The cushion flow path 211 can be formed by processing one or more radially tapered inclined slots to be shallow. In addition, although not shown, as shown in FIG. 5, the cushion flow path may be formed in a solid shape in which the inner circumferential surface is tapered so that the radius thereof becomes shorter toward the forward and backward side ports 220 and 222, as illustrated in FIG. Like the cushioned sections 7 and 9, the tapered inclined slot-shaped cushion flow path is tapered so that the radial depth becomes shallower toward the forward and backward side ports 220 and 222, and the solid cushion flow path chamfering the inlet edge portion of the inner circumferential surface thereof. A cushion flow path can also be formed.

And, as shown in Figure 17 so as to be inserted into the cushion portion 207, 209 having a variety of structures as described above, the outer peripheral surface of the piston rod 205 and the reverse boss portion 215, each of the collecting passages 214, 216 formed with a cushion flow path ) And the forward and backward cushioning rings 206 and 208 having outer diameters corresponding to the inner diameters of the cushion bushes 217 and 219 are detachably mounted, wherein each of the cushion rings 206 and 208 is a piston rod 205 and a reverse boss portion ( It may be formed integrally with the outer peripheral surface of the 215.

Another embodiment of a hydraulic cylinder according to the present invention is shown at 301 in FIG. 18.

The hydraulic cylinder 301 according to the present embodiment is applicable to the hydraulic cylinder 1, 201 having the cushion portions 7, 9, 207, 209 of all types mentioned above, and the hydraulic cylinder 1 and the hydraulic cylinder 1 as shown in FIG. 18. Similarly, the tube 302 constituting the body, the rod cover 310 and the head cover 312 inserted into the forward and backward opening surface of the tube 302, the hydraulic piston 303 reciprocating inside the tube 302 ) And the hydraulic piston rod 305.

Further, as the cushion portions 307 and 309 on the forward and backward sides of the piston 303 are inserted into the collecting holes 314 and 316, the cushion passage 311 formed between the inlet edge portions of the collecting holes 314 and 316 is gradually reduced. The cushion flow passages 333 and 335 and the forward and backward side ports 320 and 322 are formed in the rod cover 310 and the head cover 312 so that cushioning control valves 330 and 331 for adjusting the cushioning force are installed. It is to adjust the flow rate of the hydraulic fluid through the cushion flow path (337,339) connected to the).

Here, as illustrated in FIG. 18, the cushion bushes 317 and 319 detachably or integrally coupled to the outer circumferential surface of the piston rod 305 and the reverse side boss portion 315 to form the cushion portions 307 and 309 are moved forward and backward on the outer circumferential surface thereof. Square cross section whose outer diameter surface is tapered so that the radial depth deepens while maintaining a constant cross-sectional area from the piston 303 by a predetermined distance d at a radius slightly smaller than the inner diameter of the collecting holes 314 and 316. One or more cushion flow passages 311 having an inclined slot shape radially are processed, and each cushion control valve is formed by forming a protrusion 329 inserted into the reverse port 322 on the end surface of the reverse boss portion 315. The functions of 330 and 331 are more effectively utilized. At this time, although not shown, the circumferential surface is tapered so that the radius is shorter as the distance from the piston 303 is maintained from the position away from the piston 303 while maintaining a constant cross-sectional area by a predetermined distance d from the piston 303. Various types of cushion parts 307 and 309 may be applied, such as cushion bushes 317 and 319 having processed the cushion flow path 311 in the form.

According to the hydraulic cylinder 1 according to the present invention configured as described above, the piston 3 is tapered of the cushion flow path 11 from the moment when the cushion parts 7 and 9 are inserted into the collecting holes 14 and 16. Stepless deceleration starts at a speed proportional to the number of angular or oblique slots, ie cross-sectional area.

That is, as shown in FIG. 2, the piston 3 is not fitted until the cushion portions 7 and 9 are fitted into the collecting holes 14 and 16 processed in the rod cover 10 and the head cover 12. Similar to the cylinder of the hydraulic port hydraulic fluid into or out of the forward port (20) or reverse port (22). Subsequently, as the cushion portion 9 is inserted into the collecting hole 16 from the point shown by the dashed-dotted line in FIG. 2 to the point shown by the solid line, for example, the cushion flow path 11 shown in a hatched state in FIG. ) Is the cross-sectional area of the flow path expressed by the product of the width and depth of the flow path gradually decreases from left to right to reduce the flow of hydraulic oil to the reverse port (22).

Therefore, since the piston 3 discharges the hydraulic oil through the cushion flow passage 11 whose cross-sectional area decreases from the moment when the cushion portions 7 and 9 are inserted into the collecting holes 14 and 16, the shape of the cushion flow passage 11 and It gradually decelerates in proportion to the cross-sectional area and stops while touching the outer stopper, the rod cover 10 or the head cover 12.

At this time, not only the cushion parts 7 and 9 shown in FIG. 3 but also the remaining cushion flow path 11 portions are initially inserted into the collecting holes 14 and 16, and the area thereof is wide, and then into the collecting holes 14 and 16. As you go deeper, the area gradually decreases, eventually reaching zero. In addition, the hydraulic oil is discharged in proportion to this area, and the piston 3 moves at a speed proportional to the amount of hydraulic oil discharged, so that the object connected to the piston rod also moves at the speed at which the piston 3 moves. Since the speed is close to zero, the shock at rest is almost zero.

Here, the cross-sectional area of the hatched portion is about 2 mm in width, which is most preferable in consideration of practicality and workability. The depth is deeper at the initial depth, so that the passage flow rate is rapidly transferred, that is, the piston cushions 7 and 9 are collected. It is desirable to deepen the range as much as possible in order to reduce the primary deceleration shock as an important factor in minimizing the primary deceleration shock as it is similar to that before being inserted into the holes 14 and 16.

In addition, the cushion flow path 11 may be tapered to the entire cushion portion 7, 9 as shown in FIG. 5 or the size, shape, and purpose of use of the hydraulic cylinder as shown in FIG. 7 with the planar shape of the cushion flow path 11 as triangle. According to the use state of the hydraulic cylinder (1), by removing the cushion bush (17,19) from the cushion portion (7,9) according to the use state of the hydraulic cylinder (1) Another cushion bush can be replaced.

In particular, when the cushion flow path 11 is formed of a plurality of through holes 35 as shown in FIGS. 8 and 9, the cushion portions 7 and 9 are inserted into the collecting holes 14 and 16. Since the amount of hydraulic oil introduced into the through hole 35 and discharged into the distribution hole 39 is gradually reduced, it is possible to obtain the above-described piston 3 deceleration effect.

In addition, in the case of the embodiment illustrated in FIG. 17, unlike the embodiment described above, cushion portions 207 and 209 are formed on the inner circumferential surface of the collecting holes 214 and 216, but the forward and backward cushionings 206 and 208 of the piston 203 are similar to each other. Deceleration occurs only after the insertion of the true side collecting holes 214 and 216 begins. That is, the cushion rings 206 and 208 provided on the outer circumferential surface of the piston rod 205 or the reverse side boss portion 215 begin to be inserted into the collecting holes 214 and 216, and the inlet of the outer circumferential surfaces of the cushion rings 206 and 208 and the inner circumferential surfaces of the collecting holes 214 and 216. Since the cross-sectional area of the cushion flow path 211 formed by the edge portion is gradually reduced, as shown in the above embodiment, the flow rate of the hydraulic oil to the forward and backward ports 220 and 222 is reduced, and accordingly, the piston 205 is gradually decelerated, and then the road cover. It stops at 210 or the head cover 212.

In the first embodiment, the piston-mounted cushioning portions 7 and 9 are illustrated separately, and in the second embodiment, the cover-mounted cushioning portions 207 and 209 are individually illustrated and illustrated. 207 is formed, and the cushioning portion 209 is formed in the collecting hole of the head cover on the reverse side, so that the cushioning portions of the type described in the first and second embodiments can be appropriately mixed according to the use condition or operating conditions of the hydraulic cylinder. have.

In addition, in the embodiment illustrated in FIG. 18, the cushion passages 311 and 309 maintain the largest cross-sectional area of the cushion passage 311 at the moment when the cushion portions 307 and 309 are inserted into the collecting holes 314 and 316. The cross sectional area becomes small, whereby the piston 303 is subjected to stepless deceleration for a predetermined time in the same manner as in the first embodiment. Subsequently, the cushion flow passage 311 maintains a constant cross-sectional area by a predetermined distance d just before the cross-sectional area becomes zero, and the protrusion 329 moves toward the reverse port at a time when the cross-sectional area of the cushion flow passage 311 starts to become constant. Since it is inserted into the 322, the deceleration action similar to that of the first stage deceleration by the conventional hydraulic cylinder 101 is instantaneously generated in the reverse side collecting hole 316, resulting in the effect of decelerating the piston 303 in double. Similarly, by adjusting the diameter of the cushion flow path 335 by the cushion control valve 331, the shock absorbing force can be adjusted immediately and actively according to the use state.

As described above, the endlessly buffered hydraulic cylinder according to the present invention adopts an endless deceleration cushion portion instead of the conventional cushion control valve and cushion control flow path, thereby eliminating the need for a cushion control valve and eliminating the need for processing of a control valve flow path. The manufacturing cost is lowered, and furthermore, the first deceleration impact value can be minimized and the stop impact value at both ends of the cylinder can be maintained at almost zero, thus eliminating all problems caused by the impact during the first deceleration and stoppage when transferring any object to which a hydraulic cylinder is applied. As a result, it is possible to prevent impaired accuracy, stopper damage, shortening the life of related parts, etc., and improve the efficiency of product production using hydraulic cylinders.

Claims (18)

In the hydraulic or pneumatic actuator using the piston 3 reciprocating by the pressure difference between the inlet and outlet side of the hydraulic cylinder 1, the collecting holes 14 or 16 respectively recessed in the rod cover 10 or the head cover 12. It is characterized in that it is provided with a forward and backward cushioning portion (7 or 9) to gradually reduce the flow passage 11 of the hydraulic oil moving to the forward and backward ports (20, 22) by the piston (3) Stepless buffer hydraulic cylinder. The front and rear cushion side (7, 9) is composed of the front and rear cushion side (17, 19) detachably coupled to the outer peripheral surface of the front and rear boss portion (13, 15) of the piston (3). Stepless shock-absorbing hydraulic cylinder, characterized in that. According to claim 2, wherein the front and rear cushion bush (17, 19) is one or more tapered inclined slot-shaped cushion flow path 11 is radially processed so as to move away from the piston (3) Endless buffer hydraulic cylinder, characterized in that there is. 3. The endless cushioning hydraulic cylinder according to claim 2, wherein the forward and backward cushioning bushes (17, 19) are machined in the form of a tapered truncated conical surface such that the radius is shorter as the piston (3) moves away from the piston (3). . According to claim 2, wherein the front and rear cushion bush (17, 19) is one or more tapered inclined slot-shaped cushion flow path 11 is radially processed so as to move away from the piston (3) And an endless buffered hydraulic cylinder having an outer circumferential end edge tapered in a chamfered form. According to claim 2, wherein the forward and backward side cushion bush (17, 19) as the distance away from the piston (3) the side wall surface becomes wider, the depth of the slot-shaped cushion flow path 11 having a constant triangular planar cross section radially An endless cushioning hydraulic cylinder, characterized in that one or more are processed. The front and rear side cushion bushes 17 and 19 are radially penetrated so as to be larger in diameter as they move away from the piston 3, and the front and rear side adjoining holes 14 are disposed through the distribution holes 39. And a cushion passage (11) consisting of a plurality of through holes (35) connected to one side of the plurality of endlessly buffered hydraulic cylinders, characterized in that the one or more radially processed. The front and rear side cushion bushes 17 and 19 are radially penetrated in a radial direction so that the number of the front and rear cushion bushes 17 and 19 increases as the distance from the piston 3 increases. Endless buffer type hydraulic cylinder, characterized in that the one or more cushion flow path (11) consisting of a plurality of through holes 35 of the same diameter connected to the (16) is radially processed. The endless buffer hydraulic cylinder according to any one of claims 2 to 8, wherein the forward and backward side cushion portions (13, 15) are integrally formed with the forward and backward side cushion bushes (17, 19). . 9. The piston rod according to any one of claims 2 to 8, wherein the piston (3) is constituted separately from the piston rod (5), and the piston (3) and the reverse side cushion bush (19) are each a piston rod. (5) and the endless buffer hydraulic cylinder, characterized in that the removable coupling by the fastening means (21, 23, 25, 27) on the outer peripheral surface of the boss (15). 2. The endless cushioning hydraulic cylinder according to claim 1, wherein the forward and backward cushion portions (207, 209) comprise forward and backward cushion bushes (217, 219) detachably coupled to inner circumferential surfaces of the forward and backward side collecting holes (214, 216). The method of claim 11, wherein the forward and backward cushion bushes (217, 219) is one or more tapered inclined slot-shaped cushion flow path 311 is processed radially toward the forward and backward side ports (320,322) toward the inner peripheral surface Stepless buffering hydraulic cylinder, characterized in that. 12. The endless cushioning hydraulic cylinder according to claim 11, wherein the forward and backward cushion bushes (217, 219) are processed in a solid shape in which the inner circumferential surface is tapered so as to decrease in radius toward the forward and backward ports (220, 222). The method of claim 11, wherein the forward and backward cushion bushes (217, 219) has a tapered inclined slot-shaped cushion flow passage (211) is processed radially toward the forward and backward side ports (220, 222) toward the inner circumferential surface is one or more radially processed Endless buffer hydraulic cylinder, characterized in that the inner peripheral surface inlet edge is tapered in the shape of chamfered. 15. The endless buffer hydraulic cylinder according to any one of claims 11 to 14, wherein the forward and backward cushion bushes (217, 219) are integrally formed on an inner circumferential surface of the forward and backward side collecting holes (214, 216). 15. The inner diameter of the cushion bushes 217 and 219 according to any one of claims 11 to 14, wherein outer surfaces of the rod 205 and the boss portion 215 of the piston 203 inserted into the forward and backward cushion portions 207 and 209 are formed. And a forward and backward side cushioning ring (206, 208) each having a corresponding outer diameter and a detachable or integrally mounted body. 15. The rod cover 310 or the head cover 312 according to any one of claims 1 to 8 and 11 to 14, the bottom surface and the forward and backward side ports 320 and 322 of each of the collecting holes 314 and 316. Endless buffer type hydraulic cylinder, characterized in that the cushion control valve for controlling the buffer force (330, 331) is connected through the wall. 18. The method of claim 17, wherein the front and rear cushioning portion 307, 309 maintains a constant cross-sectional area of the piston 303 by a predetermined distance (d), while the cross-sectional area is gradually reduced by more than a predetermined distance (d) to the collecting hole As it is inserted into the (314, 316) to gradually reduce the cushion flow path (311) formed between the inlet edge portion of the collecting hole (314, 316), the end of the reverse side cushion portion (309) Endless buffer hydraulic cylinder, characterized in that the projection 329 is inserted into the reverse port 322 is formed.