JPS6127603B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for adjusting the stroke of a piston rod in a cylinder mechanism.

For example, when moving the cross rail or tool rest of machine tools such as planers and plano mirrors up and down using a cylinder mechanism, or when moving the ram of a press machine etc. up and down using a cylinder mechanism, the cylinder It is necessary to appropriately adjust the stroke of the piston rod in the mechanism to accurately stop it at a desired position. Particularly in hydraulic presses that use a cylinder mechanism, there are cases in which the upper and lower dies are matched to ensure accurate engagement between the upper and lower dies, and V-shaped die grooves in the lower dies. Air bending involves engaging the upper die halfway into the die groove and bending the workpiece to a bending angle larger than the angle of the die groove, without completely engaging the upper die with the lower die until the workpiece is brought into close contact with the die groove. Coining, which eliminates the elasticity of the workpiece due to the surface pressure of the die groove in the upper and lower dies and the biting of the tip of the upper die, completely eliminates spring back and bends accurately to the angle of the die. In some cases, the ram may be stopped at the desired lowering position,
After stopping it, it is necessary to lower it further and stop the descent again.

Conventionally, in order to adjust the stroke of a piston rod in a cylinder mechanism, when a limit switch set at a desired position is activated by the piston rod, etc., a solenoid valve that switches the supply of pressure oil to the cylinder is activated. Alternatively, the stroke may be forcefully adjusted mechanically by contacting a piston rod etc. with a stopper block placed on a fixed part.
Alternatively, the stroke is adjusted by opening a pressure oil release valve built into the pressurizing circuit when the piston rod reaches a desired position. However, when adjusting the stroke using a limit switch as described above, it takes time from the time the limit switch is activated until the cylinder mechanism stops, and the stop position varies and is not accurate. Further, when the stopper block is used to forcibly stop the stroke, it is difficult to adjust the stroke while applying pressure. In addition, when using a pressure oil release valve, when adjusting the stroke while pressurizing, the open area differs depending on the pressure of the pressure oil, so if the pressure of the pressure oil differs, the stroke adjustment will vary. There were other problems.

The present invention was invented in view of the above-mentioned conventional problems.The first object of the present invention is to move the piston rod or cylinder body, which performs reciprocating motion in a cylinder mechanism, to any position even during operation of the cylinder mechanism. The objective is to provide a device that can be stopped.

Another object of the present invention is to provide a device that can be easily implemented in conventional cylinder mechanisms.

Note that other objects and advantages will become clear from the detailed description given below with reference to the drawings.

FIG. 1 shows a case where the device according to the present invention is adopted in a hydraulic press. The column part 3b has a C-shape in which the column part 3b is integrally provided with an arm part 3c projecting toward the front (to the left in FIG. 1) at the top of the column part 3b. A table 5 is attached to the upper surface of the base portion 3a of the frame 3, and a lower die 7 having a V-shaped die groove 7a is attached to the upper surface of the table 5. A cylinder mechanism 9 is provided at the tip of the arm portion 3c of the frame 3.
(See Figure 2; not shown in detail in Figure 1). A lower end portion of the piston rod 11 in the cylinder mechanism 9 has a tip portion 13a that can be freely engaged with and detached from the die groove 7a of the lower mold 7.
An upper mold 13 equipped with a mold is attached via a suitable attachment 15.

As shown in detail in FIG. 2, the cylinder mechanism 9 is composed of a hollow cylindrical cylinder body 17 that is attached to a fixed part such as the frame 3, and the piston rod 11 that is slidably fitted into the cylinder body 17. It has been done. The piston rod 11 is fitted into the cylinder body 17 so that it can only slide freely, and its rotation is restricted by appropriate means, although not shown.

The piston rod 11 has a cylindrical shape with one end closed and the other end open, and the closed end 11a is slidable from a hole 19 bored in the bottom 17a of the cylinder body 17. It stands out. Note that a seal member 21 is interposed between the hole 19 and the outer peripheral surface of the piston rod 11.
A piston 23 is integrally formed on the outer peripheral surface of the open end 11b of the piston rod 11 and is slidably fitted to the inner peripheral surface of the cylinder body 17. The piston 23 divides the inside of the cylinder body 17 into a first cylinder chamber 25a and a second cylinder chamber 25b, and a piston ring 27 is fitted into the outer peripheral surface of the piston 23.

A female spiral 29 is provided on the inner peripheral surface of the cylindrical piston rod 11 over almost the entire length, and a stroke adjusting member 31 having a male spiral formed on the outer peripheral surface is screwed into this female spiral 29. The stroke adjusting member 31 has a disc shape with a recess 31a on the closed end 11a side of the piston rod 11, and divides the inside of the piston rod 11 into a first chamber 33a and a second chamber 33b. This stroke adjusting member 31 includes the first chamber 33a and the second chamber 33.
A plurality of communication holes 35 communicating with b are bored approximately on the same circle. Note that the piston rod 11
A ring-shaped withdrawal prevention member 37 is fixed to the open end 11b of the piston rod 11 with a plurality of bolts 39 in order to prevent the stroke adjustment member 31 from coming out from inside the piston rod 11.

At the center of the lid portion 17b of the cylinder body 17, the vicinity of the base of the stroke control rod 41 is located at the center of the lid portion 17b of the cylinder body 17.
It is rotatably supported via thrust bearings 43a and 43b provided on the inner and outer surfaces of 7b. Note that a nut 4 is provided at the end of the base of the stroke control rod 41 to restrict movement in the axial direction.
5 are screwed together, and the stroke control rod 4
A handle 47 is integrally attached as a device for rotating 1.

The stroke control rod 41 controls the stroke of the piston rod 11 by adjusting the positional relationship between the stroke adjustment member 31 and the piston rod 11, and extends through the stroke adjustment member 31 in a slidable manner. It reaches near the bottom 17a of the cylinder body 17. A long key 4 is provided on the body of the stroke control rod 41 in order to correspond to the maximum stroke of the piston rod 11.
9 are integrally fixed via a plurality of bolts 51. By using this key 49, the stroke adjusting member 3 relative to the stroke control rod 41 is
1 is regulated, and the stroke control rod 41 and the stroke adjustment member 31 are fitted so as to be slidable only.

The tip of the stroke control rod 41 is formed into a flange portion 53 having a relatively large diameter, and the flange portion 53 has an axial center hole 55 bored in the axial center of the stroke control rod 41 and an axial center hole 55 for the piston rod 11. A plurality of communication holes 57 communicating with the second chamber 33b are bored in the radial direction. The opening 59 of the communication hole 57 is opened toward the base of the stroke control rod 41 (upward in FIG. 2). Further, the flange portion 53 is provided with an opening 61 communicating with the axial hole 55, and this opening 61 is normally closed by a ball-shaped check valve 65 pressed by a spring 63. .

At the tip of the stroke control rod 41, there is a throttle valve element 6 that can freely throttle and adjust the state of communication between the plurality of openings 59 and the second chamber 33b of the piston rod 11.
7 is slidably fitted. This throttle valve body 67
is a type of valve body of a throttle valve mechanism, and when pressed by the stroke adjustment member 31, it gradually approaches the flange portion 53 and connects the opening 59 and the second chamber 33b. It acts to narrow down the communication state of the , and is almost disk-shaped.
A bullet 69 is mounted between the throttle valve body 67 and the flange portion 53, and the action of this bullet 69 causes the throttle valve body 67 to move toward the base of the stroke control rod 41 (in FIG. However, the sliding range is restricted by contacting the key 49.

One end (the upper end in FIG. 2) of the axial hole 55 formed in the axial center of the stroke control rod 41 is a through hole 55 formed in a direction perpendicular to the axial direction of the stroke control rod 41. The hole 71 communicates with an oil hole 73 formed in the lid portion 17b of the cylinder body 17. Note that a stroke control rod 4 is provided at a position where the lid portion 17b corresponds to the through hole 71.
1 is provided with an annular groove 75 surrounding it.

The oil hole 73 communicates with the axial hole 55 and the first chamber oil hole 7 communicates with the cylinder first chamber 25a.
A control valve 79 is interposed between the oil hole 73 and the second chamber oil hole 81 communicating with the cylinder second chamber 25b, and a four-port, two-position switching valve 83 is provided between the oil hole 73 and the second chamber oil hole 81 communicating with the cylinder second chamber 25b. There is an intervention. In addition, P of the switching valve 83
An oil passage 87 from a hydraulic pump 85 driven by a motor M is connected to the port, and a drain oil passage 89 connected to the tank T is connected to the R port. Further, a first connecting oil passage 91 connected to the second chamber oil hole 81 is connected to the A port of the switching valve 83, and a second connecting oil passage 93 connected to the oil hole 73 is connected to the B port. It's connected.

The control valve 79 controls the outflow of working fluid from the first cylinder chamber 25a in the cylinder mechanism 9. The inside of the valve casing 95 of this control valve 79 is connected to the spool chamber 9 by a partition wall 97.
9 and a drain chamber 101, and the drain chamber 101 is coaxially provided with a small-diameter pressure chamber 103. Inside the spool chamber 99 is a spool 1.
05 is slidably inserted into the spool chamber 99.
The interior is divided into a first spool chamber 99a and a second spool chamber 99b by the large diameter portion 105a of the spool 105. Small diameter portion 1 of the spool 105
05b slidably passes through the partition wall 97 and also passes through the drain chamber 101, and its tip is fitted into the pressure chamber 103 so as to be able to be fitted and removed. Note that a through hole 1 is provided in the axial center of the spool 105.
07 is drilled. In addition, the first spool chamber 99
Inside a, there is a small diameter portion 105 of the spool 105.
A bullet 109 is loaded which acts to fit the tip of the tube 10b into the pressure chamber 103.

Note that the oil hole 111 provided in the first spool chamber 99a and the first chamber oil hole 77 are connected to the third connecting oil path 1.
13, and the second spool chamber 99
The second connection oil passage 93 is connected to the oil hole 115 provided in b.
A branch oil passage 117 is connected thereto. In addition, the drain port 119 provided in the drain chamber 101 has
A drain oil passage 121 connected to the tank T is connected thereto.

Now, in the above configuration, as shown in FIG. 2, the P port and A port of the switching valve 83 are connected, and the B port and R port are connected, then the P port and the B port are connected, and the A port is connected. When the port and R port are connected, the working fluid from the hydraulic pump 85 flows through the oil passage 87, the switching valve 83, and the second connection oil passage 9.
3 and reaches the oil hole 73 of the cylinder body 17.
Further, it flows into the second chamber 33b of the piston rod 11 via the annular groove 75, the through hole 71 of the stroke control rod 41, the shaft hole 55, and the communication hole 57. The working fluid that has flowed into the second chamber 33b flows into the cylinder first chamber 25a through a plurality of holes 35 provided in the stroke adjustment member 31. Accordingly, the pressure in the first cylinder chamber 25a causes the piston rod 11 to be actuated to protrude and to move downward in FIG. Note that the fluid in the second cylinder chamber 25b flows through the second chamber oil hole 81, the first connection oil passage 91,
It is discharged into the tank T via the switching valve 83 and the drain oil path 89.

As described above, when the working fluid is being supplied from the second connecting oil passage 93, the working fluid flows into the second spool chamber 99b of the control valve 79 via the branch oil passage 117, and also flows into the cylinder first chamber 25a. The working fluid within flows into the first spool chamber 99 of the control valve 79 via the first chamber oil hole 77 and the third connecting oil passage 113,
Further, it flows into the pressure chamber 103 through a through hole 107 provided in the spool 105 . Therefore, the second
Due to the action of the pressure in the spool chamber 99b and the pressure in the pressure chamber 103, the spool 105 receives a force acting in the left direction in FIG. 109, the acting force that tries to move the spool 1 to the right in FIG.
05 is in the position shown in FIG. 2, and the drain chamber 101 and the pressure chamber 103 are in a state where communication is cut off. Therefore, in this state, the working fluid is prevented from flowing out from the first cylinder chamber 25a.

As described above, the working fluid is supplied into the first cylinder chamber 25a, the piston rod 11 is operated to protrude, and the stroke adjustment member 31 in the piston rod 11 hits the throttle valve body 67 fitted to the tip of the stroke control rod 41. When it comes into contact with this throttle valve body 6
7 and the flange portion 53 at the tip of the stroke control rod 41, the impact is alleviated by the action of the bullet 69. When the stroke adjustment member 31 comes into contact with the throttle valve body 67, the throttle valve body 67
As it gradually approaches the flange portion 53 against
The state of communication between the piston rod 11 and the second chamber 33b is gradually restricted. Therefore, the pressure inside the shaft center hole 55 gradually increases, so that the control valve 7
9, the pressure in the second spool chamber 99b gradually increases, and the pressure in the first spool chamber 99a and the action of the bullet 109 push the spool 105 to the right in FIG. The acting force that presses the spool 105 to the left in FIG. 2 becomes greater, and the spool 105 is moved to the left in FIG. Spool 1
05 is moved to the left in FIG.
01 is connected. Therefore, the working fluid in the cylinder first chamber 25a flows through the first chamber oil hole 77, the third connecting oil passage 113, and the first spool chamber 99 of the control valve 79.
a, through hole 107 of spool 105, drain chamber 1
01 and the drain oil passage 121 to the tank T. Therefore, the protruding operation (lowering in FIG. 2) of the piston rod 11 is stopped.

After the piston rod 11 stops protruding,
Rotate the stroke control rod 41 using the handle 47 to adjust the stroke adjustment member 31 to the throttle valve body 6.
7, the throttle valve body 67 is raised as shown in FIG. 33b, and the pressure in the shaft hole 55 decreases from the increased state, so that the spool 105 in the control valve 79 is returned to its original state as shown in FIG. Therefore, the piston rod 11 moves to protrude again, and the stroke adjusting member 31 comes into contact with the throttle valve body 67 again, and the opening 59
When the communication between the piston rod 11 and the second chamber 33b is restricted, the piston rod 11 stops again as described above.

Therefore, in this reference example, the stroke control rod 41 is appropriately rotated by the handle 47,
By appropriately adjusting the positional relationship between the piston rod 11 and the stroke adjustment member 31, the stroke of the piston rod 11 can be appropriately set. Further, after the piston rod 11 stops protruding, the piston rod 11 can be made to protrude again by operating the stroke control rod 41 and separating the stroke adjusting member 31 from the throttle valve body 67. Although the stroke control rod 41 is pressed upward in FIG. 2 by the force acting on the end surface of the flange portion 53, the thrust bearing 43a prevents it from coming off and rotates smoothly. It is something that can be done.

In order to retract the piston rod 11 after the piston rod 11 has been extended as described above, the switching valve 8 must be in the state shown in FIG.
This is done by switching 3. That is, in the state shown in FIG. 2, the working fluid from the hydraulic pump 85 flows into the second cylinder chamber 25b.
The fluid in the cylinder first chamber 25a flows out into the tank T. Note that the fluid in the first cylinder chamber 25a reaches the second chamber 33b of the piston rod 11 through the plurality of holes 35 of the stroke adjustment member 31, and flows through the opening 59 of the flange portion 55 and the check valve 65 portion of the stroke control rod 41. , the shaft center hole 55 and the through hole 7
1, annular groove 75, oil hole 73, second connection oil passage 93,
Tank T via the switching valve 83 and drain oil passage 89
It is leaked to. Incidentally, since a large amount of fluid flows out mainly through the check valve 65 and the like, the retraction operation of the piston rod 11 is performed rapidly.

In the above explanation, the case where the cylinder mechanism is relatively large is explained. Next, the case where the cylinder mechanism is small will be explained using FIG. 3.

In FIG. 3, a small cylinder mechanism 123
A piston 129 partitioned into a first cylinder chamber 127a and a second cylinder chamber 127b is slidably fitted into the cylinder body 125.
A piston rod 131 whose tip protrudes from 5 is integrally attached. The arm member 1 is connected to the tip of the piston rod 131 via a bolt 133.
35 is integrally attached, and this arm member 1
35 is equipped with a stroke adjustment member 137. The stroke adjustment member 137 is made of a screw rod, and is screwed so that its positional relationship with respect to the piston rod 131 can be adjusted freely, in other words, the amount of protrusion with respect to the arm member 135 can be adjusted. , a stroke adjustment member 13 is provided at the base thereof.
A handle 139 serving as an example of a position adjustment operating device for adjusting the position of 7 is integrally attached.

a first chamber oil hole 141 provided in communication with the cylinder first chamber 127a of the cylinder body 125;
A second chamber provided in communication with the second cylinder chamber 127b
A switching valve 147 with four ports and two positions is arranged between the chamber oil hole 143 and a hydraulic pump 145 driven by the motor M. P of this switching valve 147
The oil passage 14 from the hydraulic pump 145 is connected to the port.
9 is connected, and the R port is connected to the drain oil line 15.
1 is connected. Also, the A port has the second
A first connection oil passage 153 connected to the chamber oil hole 143 is connected, and a second connection oil passage 155 is connected to the B port. A throttle valve mechanism 159 is disposed between the second connecting oil passage 155 and the third connecting oil passage 157 connected to the first chamber oil hole 141, and a check valve mechanism 159 is arranged in parallel with the throttle valve mechanism 159. valve 1
61 is provided.

The throttle valve mechanism 159 is provided at a position corresponding to the stroke adjustment member 137, and the valve housing 163 includes the second connection oil passage 15.
5, and an oil hole 16 connected to the third connection oil passage 157.
7 is perforated. Further, the valve housing 163 is provided with a connection hole 171 connected to a control valve 169, which will be described later. A throttle valve body 173 is fitted into an interior 163a of a valve housing 163 in the throttle valve mechanism 159. This throttle valve body 173 throttles and adjusts the state of communication between the opening 165, the oil hole 167, and the connection hole 171, and is used to adjust the communication state between the opening 165, the oil hole 167, and the connection hole 171.
75, the opening 165 is constantly pressed in the direction of opening. The throttle valve body 173 has a protruding pin 177 that can freely come into contact with the tip of the stroke adjusting member 137 and slidably protrudes from the valve housing 163 to the outside.

The inside of the valve housing 179 of the control valve 169 is a partition wall 1.
81 to spool chamber 183 and drain chamber 185
A small diameter pressure chamber 187 is connected to the drain chamber 185. Said spool chamber 1
83 is divided into a first spool chamber 183a and a second spool chamber 183b by a large diameter portion 189a of a spool 189 that is slidably fitted therein. A bullet 191 is loaded in the first spool chamber 183a, and the first spool chamber 183a has an oil hole 1 connected to the connection hole 171 of the throttle valve mechanism 159.
93 is provided. The small diameter portion 189b of the spool 189 slidably passes through the partition wall 181,
The tip end thereof is fitted into the pressure chamber 187 so as to be able to be fitted into and removed from the pressure chamber 187. Note that a through hole 195 is bored in the axial center of the spool 189.

In addition, in the control valve 169, a branch oil passage 199 branched from the second connection oil passage 155 is connected to an oil hole 197 provided in communication with the second spool chamber 183b. 185
A drain oil passage 203 connected to the tank T is connected to a drain port 201 provided in communication with the tank T.

In this embodiment, when switching is made to connect the P port and B port of the switching valve 147 and to connect the A port and R port, the working fluid from the hydraulic pump 145 is transferred to the switching valve 147 and the second connection oil path 155. ,
The opening 165 of the throttle valve mechanism 159, the inside 163a,
The oil flows into the first cylinder chamber 127a of the cylinder mechanism 123 through the oil hole 167 and the third connection oil passage 157. Further, the fluid in the second cylinder chamber 127b of the cylinder mechanism 123 is transferred to the first connecting oil passage 15.
3. It will flow out to the tank T via the switching valve 147 and the drain oil path 151. Therefore, the piston rod 131 is operated to protrude and is lowered in FIG. In addition, the stroke adjustment member 1
37 moves in unison with the protruding operation of the piston rod 131.

As described above, when the P port and B port of the switching valve 147 are connected to supply working fluid to the cylinder first chamber 127a of the cylinder mechanism 123, the first spool chamber 183 in the control valve 169
a, Working fluid flows into the pressure chamber 187, and working fluid from the branch oil passage 199 flows into the second spool chamber 183.
It flows into b. Therefore, the pressure chamber 18
7. Due to the pressure in the second spool chamber 183b, the spool 189 is being moved to the left in FIG. Since the acting force received in the right direction is larger, the spool 189 is moved toward the small diameter portion 189 as shown in FIG.
The tip of b is held in a state where it is fitted into the pressure chamber 187.

As described above, the piston rod 131 is operated to protrude, and the tip of the stroke adjusting member 137 comes into contact with the protruding pin 177 of the throttle valve body 173 in the throttle valve mechanism 159, and the throttle valve body 173 is moved to the bullet 175.
When pressed against the opening 165 and the oil hole 167,
Since the communication relationship with the connecting hole 171 is gradually narrowed, the flow rate of the working fluid into the first cylinder chamber 127a gradually decreases, and the operation speed of the piston rod 131 gradually decreases, and the piston rod 13
1's thrust gradually decreases. On the other hand, the second connection oil passage 155, the branch oil passage 199, and the second spool chamber 183
The pressure inside b etc. gradually increases. When the pressure in the second spool chamber 183b increases and the spool 189 in the control valve 169 is moved to the left in FIG.
The tip of the spool 1 separates from the pressure chamber 187 and the spool 1
A through hole 195 provided in the drain chamber 89 communicates with the drain chamber 185. Therefore, the fluid in the inside 163a of the throttle valve mechanism 159 is transferred to the connection hole 171 and the control valve 16.
9 first spool chamber 183a, through hole 195 of spool 189, drain chamber 185, drain oil passage 20
3 to the tank T, and the cylinder mechanism 12
The supply of working fluid to the cylinder first chamber 127a of No. 3 is stopped. Therefore, the thrust of the piston rod 131 becomes small and the ejection operation is stopped.

As mentioned above, the tip of the stroke adjustment member 137 is connected to the throttle valve body 173 in the throttle valve mechanism 159.
The cylinder mechanism 1 comes into contact with the protruding pin 177 of the
When the protruding operation of the piston rod 131 at 23 is stopped, when the tip of the stroke adjusting member 137 is released from the protruding pin 177 by turning the handle 139, the action of the bullet 175 loaded in the throttle valve mechanism 159 Throttle valve body 173
is raised in FIG. 3, and the communication between the throttled opening 165, the oil hole 167, and the connecting hole 171 is opened, so that the spool 189 in the control valve 169 returns to its original state as shown in FIG. The state is restored, and the piston rod 131 in the cylinder mechanism 123 is operated to protrude again.

After the piston rod 131 in the cylinder mechanism 123 is operated to protrude, the piston rod 1
31 is retracted and operated by connecting the P port and the A port of the switching valve 147, and connecting the B port and R port of the switching valve 147, as shown in FIG. With this connection, the working fluid from the hydraulic pump 145 is transferred to the cylinder mechanism 123.
The fluid in the cylinder first chamber 127a is supplied to the third connecting oil passage 157, the check valve 161, and the throttle valve mechanism 1.
59, the second connection oil passage 155, the switching valve 147, and the drain oil passage 151, and are discharged to the tank T. Incidentally, since the oil in the first cylinder chamber 127a is mainly discharged through the check valve 161, the retraction operation of the piston rod 131 is performed rapidly.

As can be understood from the above description of the embodiments, the present invention has the configuration as described in the claims, and therefore the stroke adjusting member is integrated with the throttle valve body in the throttle valve mechanism and the piston in the cylinder mechanism. When the piston rod comes into contact with the piston rod and the opening of the throttle valve mechanism is gradually narrowed, the working fluid flowing into the first cylinder chamber of the cylinder body gradually decreases, and the piston rod gradually slows down and finally stops. . In other words, since the opening is narrowed and the amount of working fluid flowing into the first cylinder chamber gradually decreases, the thrust of the piston rod gradually decreases. When the piston rod is stopped, the first cylinder chamber and the drain oil passage are connected via the control valve.
The pressure in the first cylinder chamber is maintained at a pressure balanced with the load acting on the piston rod under the influence of the throttling action of the control valve and throttle valve mechanism. Therefore, when the piston rod is stopped, no surge pressure is generated in the first cylinder chamber, and furthermore, after the piston rod is stopped, no excessive pressure is generated in the first cylinder chamber.
In addition, after the piston rod has stopped, the contact pressure between the stroke adjustment member and the throttle valve body does not become large because the pressure oil in the connecting oil passage is drained via the control valve, so the contact pressure between the stroke adjustment member and the throttle valve body does not become large. The adjustment member can be easily operated and finely adjusted. Therefore, after one stop,
The piston rod can be easily moved slightly if necessary. Furthermore, according to the present invention,
Since the throttle valve mechanism is provided outside the cylinder mechanism, it can be implemented relatively easily even in conventional cylinder mechanisms by simply attaching a stroke adjusting member to the reciprocating piston rod or cylinder body in an adjustable manner. be.

Although the present invention has been described using a hydraulic press as an example, it is not limited to a hydraulic press.
It can be easily used in other machines as well.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is an overall schematic diagram showing a case where the apparatus according to the present invention is used in a hydraulic press. FIG. 2 is an explanatory diagram showing a reference example of the device according to the present invention. FIG. 3 is an explanatory view of the operation of an embodiment of the device according to the present invention. (Explanation of symbols representing main parts of drawings), 1
23... Cylinder mechanism, 125... Cylinder body, 129... Piston, 131... Piston rod, 137... Stroke adjustment member, 159
... Throttle valve mechanism, 169 ... Control valve, 173 ...
Throttle valve body.

Claims (1)

[Claims] 1. A piston rod 131 is integrally provided on the piston 129 fitted into the cylinder body 125 of the cylinder mechanism 123, and the piston 12
Between the first cylinder chamber 127a divided by 9 and the connecting oil passage connected to the hydraulic pump 145,
From the hydraulic pump 145 to the cylinder first chamber 12
A throttle valve mechanism 1 is provided with a freely slidable throttle valve body 173 that can freely adjust the throttle opening 165 that communicates with the throttle valve 7a.
59, and a stroke adjusting member 137 is installed on the piston rod or the cylinder body so as to be adjustable in position, and is provided so as to be able to come into contact with the throttle valve body 173 of the throttle valve mechanism 159, and the stroke adjustment member 137 is provided so as to be able to come into contact with the throttle valve body 173 of the throttle valve mechanism 159, and is connected to the cylinder first chamber 127a. Between the branch oil passage 199 branched from the oil passage, the cylinder first chamber 1
The cylinder first chamber 1 is used to control the pressure inside the cylinder 27a.
27a to the drain oil path 203, the control valve 169 is slidably equipped with a spool 189 that can be freely connected and disconnected.
A stroke adjustment device for a cylinder mechanism, characterized in that it is provided by arranging.