JP3765521B2 - Fluid pressure device - Google Patents

Description

[0001]
The present invention relates to a fluid pressure device having a reciprocating actuator. The present invention also relates to a working machine having the fluid pressure device.
[0002]
[Prior art]
For example, in an agricultural boom sprayer, the ground surface height may be adjusted according to the height of the crop, or to avoid collision with crops and obstacles during the spraying operation. The boom can be adjusted by adjusting the vertical position of the boom. For example, a hydraulic reciprocating actuator is used as a drive source for adjusting the vertical position of the boom because a large output can be obtained.
[0003]
When a single-rod actuator is used as the reciprocating actuator, the boom is driven upward in the extension stroke of the operating rod of the actuator, and the boom is lowered in the retracting stroke of the operating rod. Usually, a fluid pressure circuit is configured so that a large thrust is exerted when the boom is driven to rise.
[0004]
[Problems to be solved by the invention]
However, in this case, since the boom's own weight also acts, there is a problem that the lowering operation speed of the boom is increased. On the other hand, for example, when the boom is raised, even if the discovery of an obstacle is delayed, the boom can be quickly raised so that it can be instantly avoided, while the boom is lowered. Sometimes it is desirable to be able to slowly lower the boom so as not to impair the stability of the traveling aircraft or to generate a large impact when the boom lowering operation is stopped.
[0005]
In order to guarantee such an ideal operation, when the boom is driven up, a large amount of the working fluid is quickly flowed into the fluid chamber of the reciprocating actuator, while when the boom is driven down, the fluid The working fluid may be allowed to flow out from the chamber slowly and little by little.
[0006]
For this reason, for example, in construction machines and the like, the drive control of the reciprocating actuator is currently performed using a complicated and sophisticated control method.
[0007]
The present invention has been made in view of such circumstances, and a fluid pressure device, a working machine, and the like capable of performing the above-described ideal control of a reciprocating actuator in a simple method and at low cost. It is intended to provide a valve body and a back flow control valve device suitable for use.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, a fluid pressure device according to the present invention according to claim 1 includes a fluid chamber having a working fluid inlet / outlet, and a cylindrical shape that surrounds the saddle fluid inlet / outlet and protrudes outside the previous fluid chamber. Between the connecting cylinder part, a reciprocating actuator having a step part between the connecting cylinder part and the working fluid inlet / outlet, and a pipe joint screwed into the connecting cylinder part, the working fluid when the outflow from the fluid chamber is interposed in contact with the valve body to the stepped portion at the time of flowing into the fluid chamber of the working fluid seated on an end surface of the fitting in the connecting cylindrical portion, the valve body, the A valve shaft that forms an annular gap with the inner peripheral surface of the fluid flow hole of the pipe joint, a groove that forms a working fluid passage with a large inflow amount between the stepped portion, and the end surface. when it has also permitted the flow of a predetermined amount of the working fluid the axial direction In the middle, in which and a throttle passage having a pressure receiving surface for receiving the fluid pressure by the fluid when the working fluid flows in a direction away said valve body from said end face.
[0009]
According to the present invention described in claim 1, wherein when the working fluid flows into the fluid chamber of the reciprocating actuator, the valve body the valve body is abutting to Runode the stepped portion, the stepped portion A large amount of the working fluid quickly flows into the fluid chamber through the groove between the actuator and the actuator, and the actuator operates quickly.
[0010]
On the other hand, when the working fluid flows out of the fluid chamber, the valve body is seated on the end face of the pipe joint, so that the amount of the working fluid flowing out of the fluid chamber is only allowed by the throttle passage. Regulated to be quantitative. Therefore, the actuator operates slowly. Further, since the valve body is integrally provided with a valve shaft that is inserted into the pipe joint so as to be movable in the axial direction, reciprocation of the valve body is guided by the pipe joint and the valve shaft. Therefore, the operation is reliable. Furthermore, since the throttle passage is provided with a pressure receiving surface that receives a fluid pressure by the working fluid when the valve body flows in a direction away from the end surface, the detachment operation of the valve body from the end surface is reliable. .
[0011]
When the fluid pressure device is applied to, for example, a boom sprayer as a working machine as described in the section of the prior art, it is preferable to configure the fluid pressure circuit as follows. That is, when the working fluid flows into the fluid chamber of the reciprocating actuator, the boom as a driven member is driven to rise, and when the working fluid flows out of the fluid chamber, the boom is lowered. Next, a fluid pressure circuit is configured. If it does in this way, with the simple composition, the above-mentioned boom can be rapidly driven up, and it can be surely lowered gently.
[0012]
A fluid pressure device according to a second aspect of the present invention is the fluid pressure device according to the first aspect, wherein the reciprocating actuator is a single rod actuator, and the fluid chamber is on the side of the counteracting rod of the single rod actuator. It is located in. In this way, when the working fluid flows into the fluid chamber, a large thrust is obtained by the actuator, and conversely, when the working fluid flows out from the fluid chamber, the gentle operation of the actuator is guaranteed. Therefore, it is more preferable.
[0016]
A working machine according to a third aspect of the present invention includes the fluid pressure device according to the first or second aspect and a driven working member driven by the reciprocating actuator. . According to this configuration, for example, in an agricultural boom sprayer, it is possible to quickly raise the boom. On the other hand, when the boom is lowered, it is possible to obtain an effect that does not generate a large impact on the boom.
[0017]
The working machine according to a fourth aspect of the present invention is characterized in that the reciprocating actuator is a single rod type actuator, and is located on the counter-acting side of the single rod type actuator. The effect in this case is the same as that of the second aspect.
[0018]
According to a fifth aspect of the present invention, there is provided a work machine according to the present invention, wherein the driven work member is a heavy object that is driven in a vertical direction, and the driven work member is driven upward by an extension stroke of the reciprocating actuator. It is characterized in that it can be In this way, a particularly great effect can be obtained when the driven work member is driven upward.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a preferred embodiment of the invention will be described with reference to the accompanying drawings.
[0026]
FIG. 1 is a perspective view of an agricultural boom sprayer as an example of a working machine including a fluid pressure device according to an embodiment of the present invention. The boom sprayer includes a telescopic boom 3 of a one-side spray system at the rear part of a riding traveling machine body 2 on which a tank 1 for storing a spray liquid such as a chemical liquid is mounted. A large number of spray nozzles 4 are attached to the lower surface of the boom 3 at appropriate equal intervals in the length direction. The boom sprayer performs a wide spraying operation at a time by the numerous spray nozzles 4 while traveling while extending the boom 3 to the left or right side of the traveling machine body 2 for a long time.
[0027]
The boom sprayer includes a boom folding mechanism 5, a boom turning mechanism 6, a boom lifting mechanism 7, and a boom up / down swing mechanism 8.
[0028]
The boom folding mechanism 5 includes a boom folding pivot connecting portion 11 provided between the boom support base 9 and the turning frame 10, and a hydraulic pressure provided between the boom support base 9 and the turning frame 10. A boom folding drive actuator 12 such as a cylinder, and for the convenience of storage and movement, the boom 3 is moved around the boom folding pivot connecting portion 11 as shown in FIG. This is to allow folding along one side of the traveling machine body 2.
[0029]
The boom turning mechanism 6 is installed between a boom turning pivot connecting portion 14 provided between a base end portion of the turning frame 10 and the lifting frame 13, and between the turning frame 10 and the lifting frame 13. A boom turning drive actuator 15 such as a hydraulic cylinder, and the turning frame 10 is turned 180 degrees in a horizontal plane behind the traveling machine body 2 around the boom turning pivot connecting portion 14. Thus, the direction of the boom 3 can be changed on both the left and right sides of the traveling machine body 2.
[0030]
The boom elevating mechanism 7 is driven via the elevating frame 13, a pair of left and right guide rails 16 and 16 for guiding the elevating frame 13, and a moving pulley 17 and a wire 18 as transmission means for the elevating frame 13. An upwardly-coupled boom lifting / lowering actuator 19 such as a hydraulic cylinder, and the vertical movement of the lifting frame 13 along the pair of left and right guide rails 16 and 16 fixed to the rear part of the traveling machine body 2. It is intended to enable adjustment of the spray ground height by the boom 3 by moving in parallel.
[0031]
The boom up / down swing mechanism 8 includes a boom up / down swing pivot connecting portion 20 provided between a base end portion 3a of the boom 3 and the boom support base 9, the boom 3 and the boom support base. 9 and a boom vertical swing drive actuator 21 such as a hydraulic cylinder installed between the boom 9 and the boom 3 swing pivot connecting portion 20 as a center, and the tip 3b side of the boom 3 up and down. By swinging, for example, it is possible to avoid the boom 3 from colliding with a crop or an obstacle during spraying while traveling.
[0032]
A fluid pressure device according to an embodiment of the present invention is applied to the boom up-and-down swing mechanism 8.
[0033]
FIG. 2 is a fluid circuit diagram of the boom up-and-down swing mechanism 8. In FIG. 2, the base end portion 3a of the boom 3 as a driven work member is inserted into an opening portion of the boom support base 9 having a U-shaped horizontal section, and the boom up-and-down swing pivot connecting portion 20 is connected to the boom support base 9. It is pivotally fixed to the upper part of the boom support base 9 via a horizontal boom pivot shaft 22 that constitutes the boom.
[0034]
In the illustrated example, the boom up-and-down swing driving actuator 21 is a single-rod double-acting reciprocating hydraulic cylinder, and the boom support base 9 as a fixed portion and the boom 3 are interposed between the boom support base 9 and the boom 3. The boom 3 is installed so that the boom 3 is driven to swing upward in the extension stroke of the boom up / down swing driving actuator 21. Specifically, a base side stay 23 projects downward from the lower part of the boom support base 9, while a boom side stay 24 is formed on the lower surface of the boom 3 near the base end 3 a. It protrudes downward. A base end portion 25a side of a cylinder 25 of the boom up / down swing driving actuator 21 is connected to the base side stay 23 via a base side horizontal pivot shaft 26 so as to be relatively rotatable. On the other hand, a tip end portion 27a of an operating rod 27 of the boom up / down swing driving actuator 21 is connected to the boom side stay 24 via a boom side horizontal pivot shaft 28 so as to be relatively rotatable.
[0035]
In the boom up-and-down swing driving actuator 21, the piston 25 as an actuator fixed to the base end portion 27 b accommodated in the cylinder 25 of the operating rod 27 is placed in the cylinder 25 in FIG. 2. As seen, the two oil chambers 30 and 31 are defined as fluid chambers. Here, the operating rod 27 extends so as to pass through the right oil chamber 31, and for this reason, the right oil chamber 31 is a small diameter oil chamber, and the left oil chamber 30 is a large diameter oil chamber. It has become. Since the pressure receiving area of the large diameter oil chamber side pressure receiving surface 29 a of the piston 29 is larger than that of the small diameter oil chamber side pressure receiving surface 29 b of the piston 29, the working oil F that is a working fluid is supplied into the large diameter oil chamber 30. Then, the operating rod 27 extends with a large force, and the boom 3, which is a heavy object, is driven to swing upward quickly and reliably.
[0036]
2, a hydraulic pump 32 mounted on the traveling machine body 2 is driven by an internal combustion engine 33 (see FIG. 1) mounted on the traveling machine body 2, and an oil tank 34 also mounted on the traveling machine body 2. The hydraulic oil F as the internal hydraulic fluid is pumped to the hydraulic oil discharge pipe 35. The hydraulic oil discharge line 35 communicates with a boom up / down swing drive direction switching valve 37 via a check valve 36. The boom up / down swing drive direction switching valve 37 communicates with the two oil chambers 30, 31 of the boom up / down swing drive actuator 21 through a first oil feed pipe 38 and a second oil feed pipe 39. . The boom up / down swing drive direction switching valve 37 communicates with the oil tank 34 through a return line 40. An appropriate type of pressure control valve 41 is interposed between the hydraulic oil discharge pipe 35 and the return pipe 40, and when the hydraulic pressure in the hydraulic piping system exceeds a set value, the hydraulic pressure is increased. An amount corresponding to the excess hydraulic pressure in the hydraulic oil F pumped by the pump 32 is automatically returned to the oil tank 34.
[0037]
The boom up-and-down swing drive direction switching valve 37 is, for example, a spring return type three-position four-port valve, and is always urged in a direction in which the four ports are automatically returned to the neutral position where all the four ports are closed. Yes. When a boom upward swing command is issued from the driver of the traveling machine body 2 by an operation member such as a lever (not shown), the hydraulic circuit is switched by the boom up / down swing drive direction switching valve 37, and The hydraulic oil F is pumped into the large-diameter oil chamber 30 of the boom up-and-down swing driving actuator 21 through the first oil-feeding pipe 38, and the hydraulic oil F in the small-diameter oil chamber 31 is The oil rod 34 is returned to the oil tank 34 through the two oil feed pipes 39, and the operating rod 27 of the boom up / down swing driving actuator 21 is driven in the extending direction, so that the boom 3 is connected to the boom pivot shaft 22. Oscillates around the center. Conversely, when a boom downward swing command is issued from the driver by the operating member, the hydraulic circuit is switched by the boom up / down swing drive direction switching valve 37 and the second oil feed conduit 39 is used to switch the hydraulic circuit. The hydraulic oil F is pressure-fed into the small-diameter oil chamber 31 of the boom vertical swing drive actuator 21, and the hydraulic oil F in the large-diameter oil chamber 30 passes through the first oil supply pipe 38 and the oil. Returning to the tank 34, the operating rod 27 of the boom up / down swing drive actuator 21 is driven in the retracting direction, and the boom 3 swings downward about the boom pivot shaft 22.
[0038]
By the way, the reason why the boom 3 can be swung up and down is that the boom 3 can be prevented from colliding with an obstacle or the like mainly during the spraying operation while traveling as described above. It is for doing so. Therefore, it is desirable that the upward swing of the boom 3 is performed as quickly as possible. On the other hand, the downward swing of the boom 3 does not impair the stability of the traveling machine body 2 or cause a large impact when the downward swing operation of the boom 3 is stopped. It is desirable to be performed moderately and gently. However, if no measures are taken, the weight of the boom 3 which is a heavy object is also affected, and the swing speed of the boom 3 downward tends to increase, which is not preferable.
[0039]
Therefore, in this embodiment, a reverse flow control valve device is provided in the hydraulic piping system between the boom up / down swing drive direction switching valve 37 and the large-diameter oil chamber 30 of the boom up / down swing drive actuator 21. 42 is interposed. The reverse flow control valve device 42 automatically reduces the outflow amount of the hydraulic oil F from the large-diameter oil chamber 30 as compared with the inflow amount of the hydraulic oil F into the large-diameter oil chamber 30. Play. Here, as shown in FIG. 2, the reverse flow control valve device 42 extends from the boom up / down swing drive direction switching valve 37 to the large-diameter oil chamber 30 side of the boom up / down swing drive actuator 21. It is interposed between the tip end portion 38 a of the first oil feed pipe 38 and the hydraulic oil inlet / outlet portion 43 of the large-diameter oil chamber 30.
[0040]
FIG. 3 is an enlarged longitudinal sectional view showing the configuration and operating state of the reverse flow control valve device 42 in FIG. 3, (a) on the left side shows the operating state of the reverse flow control valve device 42 when the hydraulic oil F flows into the large-diameter oil chamber 30, and (b) on the right side shows The operating state of the reverse flow control valve device 42 when the hydraulic oil F flows out from the large-diameter oil chamber 30 is shown.
[0041]
Referring to FIG. 3, the hydraulic oil inlet / outlet portion 43 of the large-diameter oil chamber 30 of the boom up / down swing driving actuator 21 includes a hydraulic oil inlet / outlet 44 formed in a peripheral wall of the cylinder 25, and And a cylindrical connecting tube portion 45 surrounding the hydraulic oil inlet / outlet port 44 and projecting outward from the cylinder 25. The connecting tube portion 45 and the tip end portion 38a of the first oil feeding pipe line 38 are respectively screw-coupled to tapered male screw portions 46b and 46c at both ends of a nipple joint 46, which is a well-known pipe joint. They are connected to each other through 46.
[0042]
A flat end surface 46 a is formed on the cylinder 12 side of the nipple joint 46 , and a valve body 47 is interposed. When the hydraulic oil F flows into the large-diameter oil chamber 30 of the cylinder 25, the valve body 47 is pushed by the hydraulic oil F and moves away from the end face 46a of the nipple joint 46 . Thereby, the hydraulic oil F can flow in a large amount into the large-diameter oil chamber 30 through between the end face 46 a and the valve body 47.
[0043]
In the present embodiment, the valve body 47 includes a valve main body 48 and the valve body 48, as is apparent from FIG. 4 which is an overall perspective view thereof and FIG. 5 which is a cross-sectional view taken along line VV of FIG. The valve body 49 has a valve shaft 49 extending downward from the center of the lower surface of the valve main body portion, and has a mushroom-like shape integrally with the top and bottom.
[0044]
The valve main body 48 has a disk shape having an outer diameter smaller than the inner diameter of the female thread of the connection cylinder 45, and the inside of the connection cylinder 45 according to the flow direction of the hydraulic oil F is shown in FIG. It moves in the axial direction between the seating position on the end face 46a of the nipple joint 46 shown in (b) and the non-sitting position away from the end face 46a shown in FIG. 3 (a). In the illustrated example, the non-sitting position of the valve body 48 is such that the valve body 48 abuts on a step portion 50 (see FIG. 3) between the connecting cylinder 45 and the hydraulic oil inlet / outlet 44. It is prescribed by
[0045]
The valve shaft 49 is inserted into the fluid circulation hole 46d of the nipple joint 46, and has an effect of guiding the reciprocating movement of the valve main body portion 48 along the accurate axial direction. As shown in FIG. 3, an annular gap 51 is formed between the outer peripheral surface of the valve shaft 49 and the inner peripheral surface of the fluid circulation hole 46 d of the nipple joint 46. Since the annular gap 51 serves as a passage when the hydraulic oil F flows into the large-diameter oil chamber 30 of the cylinder 25, the action of guiding the accurate reciprocating movement of the valve body 48 is inhibited. It is desirable to make it as large as possible within the range where there is no.
[0046]
A groove 52 is formed on the upper surface of the valve body 47 to define a hydraulic oil passage between the valve body 47 and the cylinder 25 when the valve body 47 is in the non-sitting position with respect to the end surface 46a. The groove 52 is formed in a wide and deep groove shape on the upper surface of the valve main body 48 as shown in FIG. 4 in order to maximize the inflow amount of the hydraulic oil F into the large-diameter oil chamber 30. It is desirable. By providing the wide groove 52, a pair of relative convex portions 53, 53 are formed on the upper surface of the valve main body 48 at positions facing each other. When the valve body 47 is in the non-sitting position shown in FIG. 3 (a), the pair of relative convex portions 53, 53 are located between the connecting cylinder portion and the hydraulic oil inlet / outlet port 44. A flow path for the hydraulic oil F is secured by contacting the stepped portion 50.
[0047]
Further, the valve body 47 reduces the amount of the hydraulic oil F flowing out of the large-diameter oil chamber 30 to a predetermined amount when the operating rod 27 of the boom up / down swing driving actuator 21 operates in the retracting direction. As shown in FIGS. 4 and 5, a hydraulic oil outflow permissible hole 54 is provided as a restricting passage to be regulated. The hydraulic oil flow allowance hole 54 is formed at the center of the valve main body 48 and penetrates the valve body 47 along the vertical axis direction. By appropriately setting the diameter of the hydraulic oil flow allowance hole 54, the retracting speed of the working rod 27 can be regulated to a desired speed.
[0048]
In the illustrated example, as clearly shown in FIG. 5, when the hydraulic oil F flows in the direction of separating the valve body 47 from the end surface 46 a in the middle of the axial direction of the hydraulic oil flow allowance hole 54, that is, When the hydraulic oil F flows into the large-diameter oil chamber 30 of the cylinder 25, a pressure receiving surface 54a is formed so as to easily receive a fluid pressure from the hydraulic oil F. In this way, since the pressure receiving surface 54a also receives the fluid pressure of the hydraulic oil F, the valve body 47 is detached from the end surface 46a when the hydraulic oil flows into the large-diameter oil chamber 30. There are advantages such as more reliable operation.
[0049]
Next, the operation of the reverse flow control valve device will be described with reference to FIG.
[0050]
When the hydraulic oil F is pressure-fed toward the large-diameter oil chamber 30 of the cylinder 25 by the switching operation of the hydraulic circuit by the driver, as shown in FIG. When pushed, the valve body 47 moves to the non-sitting position, and the pair of relative convex portions 53, 53 of the valve body 47 are pressed against the stepped portion 50. At this time, the hydraulic oil F flows between the annular gap 51 between the valve shaft 49 and the nipple joint 46, and between the outer peripheral surface of the valve main body portion 48 and the inner peripheral surface of the connecting cylinder portion 45. A large amount quickly flows into the large-diameter oil chamber 30 through the annular gap 60 and the hydraulic oil passage defining groove 52. Further, a part of the hydraulic oil F flows into the large-diameter oil chamber through the hydraulic oil flow allowance hole 54. Therefore, the operating rod 27 extends from the cylinder 25 with a large thrust and at a high speed. For this reason, the boom 3 is quickly driven to swing upward.
[0051]
On the other hand, when the hydraulic oil F is pressure-fed toward the small-diameter oil chamber 31 of the cylinder 25 by the switching operation of the hydraulic circuit by the driver, the piston 29 pushes out the large-diameter oil chamber 30. Pushed by the hydraulic oil F, the valve body 47 moves to the seating position on the end face 46a. In this state, the valve main body portion 48 is in close contact with the end face 46 a, so that the outflow amount of the hydraulic oil F is predetermined by the throttling action of the hydraulic oil outflow allowance hole 54 formed in the valve body 47. It is regulated to a small amount. Therefore, the operating rod 27 moves in the retracting direction at a predetermined gentle speed, and therefore the swinging speed of the boom 3 downward is restricted to a predetermined gentle speed.
[0052]
When the hydraulic oil pressure in the hydraulic piping system exceeds a set value due to the hydraulic oil flow rate regulating action by the hydraulic oil flow allowance hole 54, the hydraulic oil F of the hydraulic oil F pumped by the hydraulic pump 32 is used. The amount corresponding to the excess hydraulic pressure is automatically returned to the oil tank 34 through the return line 40 by the action of the pressure control valve 41. Therefore, there is no problem that the hydraulic piping system is damaged by applying an excessive load to the hydraulic piping system.
[0053]
In the present embodiment, in order to achieve the object of the present invention, only the valve body 47 newly produced is used, and other configurations, for example, the cylinder 25, the nipple joint 46, etc. The thing is used as it is. Therefore, the above-mentioned effect can be obtained with a simple configuration by simply adding the valve body 47 to a conventionally known mechanism, which is very advantageous in terms of cost.
[0054]
In the present embodiment, the fluid pressure device according to the present invention has been described in detail with respect to the example in which the boom up-and-down swing mechanism 8 is applied. However, for example, the present invention is applied to the boom elevating mechanism 7 shown in FIG. Even in this case, the same effect as described above can be obtained. That is, the fluid pressure device according to the present invention can be widely applied to a mechanism for driving a heavy object using a reciprocating actuator, and is particularly optimal when used for driving a heavy object in the vertical direction.
[0055]
Furthermore, instead of the hydraulic type such as the hydraulic pressure described in the present embodiment, a pneumatic type such as an air pressure can be used.
[Brief description of the drawings]
FIG. 1 is a perspective view of an agricultural boom sprayer as an example of a working machine including a fluid pressure device according to an embodiment of the present invention.
FIG. 2 is a hydraulic circuit diagram of a boom up-and-down swing mechanism provided with a fluid pressure device according to an embodiment of the present invention.
FIG. 3 is an enlarged cross-sectional view showing the configuration and operating state of the flow control valve device of FIG. 2;
4 is an overall perspective view of the valve body in FIG. 3. FIG.
5 is a cross-sectional view taken along arrow VV in FIG. 4;
[Explanation of symbols]
3 Driven work member (boom)
21 reciprocating actuator
(Boom up / down swing actuator, single rod actuator)
27 Actuating rod 30 Fluid chamber 44 Working fluid inlet / outlet 45 Connection cylinder 46 Pipe joint (nipple joint)
46a (end of pipe joint) 47 Valve body 49 Valve shaft 50 Step portion 52 Groove 54 Throttle passage (operating oil outflow allowable hole)
54a Pressure receiving surface

Claims (5)

A fluid chamber (30) having a working fluid inlet / outlet (44); a cylindrical connecting tube portion (45) surrounding the working fluid inlet / outlet (44) and projecting outward from the fluid chamber (30); A reciprocating actuator (21) having a step portion (50) between a tube portion (45) and the working fluid inlet / outlet port (44), and a pipe joint screw-coupled into the connection tube portion (45) ( 46), when the working fluid (F) flows out of the fluid chamber (30), it sits on the end surface (46a) of the pipe joint (46) in the connecting tube portion (45) and operates. When the fluid (F) flows into the fluid chamber (30), a valve body (47) that contacts the stepped portion (50) is interposed, and the valve body (47) is a fluid of the pipe joint (46). valve shaft to form an annular gap (51) between the inner peripheral surface of the flow hole (46d) and (49), said stage Permissible groove (52) for forming a large working fluid passage inflow between the (50), the outflow of the end surface even when seated in (46a) a predetermined amount of the working fluid (F) In the middle of the axial direction, a pressure receiving surface (54a) that receives fluid pressure by the fluid (F) when the working fluid (F) flows in a direction separating the valve body (47) from the end surface (46a). And a throttle passage (54) having a fluid pressure device. Said reciprocating actuator is a single rod type actuator (21), said fluid chamber (30) is positioned in a counter-actuating rod (27) side of the single rod type actuator (21), according to claim 1 Fluid pressure device.   A working machine comprising the fluid pressure device according to claim 1 and a driven work member (3) driven by the reciprocating actuator (21).   The operation according to claim 3, wherein the reciprocating actuator is a single rod actuator (21), and the fluid chamber (30) is located on the counteracting rod (27) side of the single rod actuator (21). Machine.   The driven work member (3) is a heavy object that is driven in the vertical direction, and the actuator (21) is extended so that the driven member (3) is driven upward in a stroke. Item 5. The working machine according to Item 3 or 4.

Images