JP3161323U - Hydraulic shock absorbing valve - Google Patents

Abstract

The present invention provides a hydraulic actuator and a hydraulic control device used in a press machine or the like, and a hydraulic shock buffering valve for buffering a shock pressure and a shock sound generated in a hydraulic fluid in a hydraulic pipe. An adjustment insert 9 in which a plurality of flow paths are provided in a shape and valve structure that disturbs a surface portion of a piston 7 on the oil chamber 5 side, and is coaxially screwed into a spring receiving surface 7b of the piston 7 and an adjustment cover 8. And an adjusting rod 11 for adjusting the amount of movement when the piston 7 moves to the oil chamber 6 side. On the other hand, a large-diameter annular oil chamber 14 connecting the oil chamber 5 and the oil chamber 6 to the valve body 2 via a plurality of flow paths 3 in the cylinder 4, and hydraulic fluid enters and exits from the annular oil chamber 14. A flow path 15, a piping port 15 a connected to the flow path, a flow path hole 16 a through which hydraulic fluid can enter and exit the oil chamber 5, and a piping port 16 b connected to the flow path. Thus, the function of the hydraulic shock absorbing valve 1 based on the operation of the hydraulic actuator is achieved. [Selection] Figure 2

Description

Industrial application fields

  The present invention particularly relates to a hydraulic control device used in a press machine, a waste material crusher, a cutting machine, and the like. Depending on the state of external force applied during operation of the machinery, the hydraulic actuator, the hydraulic control device, and the hydraulic The present invention relates to a hydraulic shock-absorbing valve that buffers shock pressure generated in hydraulic fluid in a pipe and shock force and shock sound (impact sound) caused in the process of propagation of a pressure wave converted from the shock pressure.

In machinery in this field, it is common to use a hydraulic actuator having a characteristic of exerting a large force with a small volume, and to install and operate a hydraulic control device and hydraulic piping.
The hydraulic control device plays a role of giving various energy to the hydraulic fluid and controlling various hydraulic pressures. The hydraulic actuator plays a role of punching, crushing, and cutting a workpiece by directly or indirectly dropping or rotating a die or a blade depending on a driving method of the machine. The hydraulic piping is installed between the hydraulic control device and the hydraulic actuator and is responsible for the flow path of the hydraulic fluid that is a medium.
Due to the machines having such characteristics, the external force applied to the hydraulic actuator varies greatly depending on the physical properties and shape of the workpiece to be processed by punching, crushing or cutting. Therefore, oil pressure generated in the押油chamber side line of the hydraulic actuator △ P _H varies according to the degree of the external force, and the set value of the pressure control valve and the maximum value thereof that is equipment pressure line of the hydraulic control device Become. Although varied by the pressure characteristics of the pressure control valve, hydraulic fluid as the hydraulic power △ P _H is high oil pressure, since the oil discharge from the tank port to the tank line of the pressure control valve, the lack of that amount Therefore, the hydraulic actuator operates at a low speed. However, as soon as punching or crushing and cutting finished, the operation of the hydraulic actuator suddenly changes from low speed to high speed, oil pressure △ P _H of押油chamber side line of the hydraulic actuator is reduced instantaneously. On the other hand, an impact pressure that is several times larger than the set value of the pressure control valve is generated in the oil pulling chamber side line of the hydraulic actuator. Also, in the process of propagation of the pressure wave converted from the impact pressure, it collides with part of the hydraulic piping and hydraulic control valve, so the welded part of the pipe joint constituting the hydraulic piping and the valve body of the hydraulic control valve, etc. Cracks, damage to the support that supports the piping, and so on. Moreover, it was also troubled by abnormal noise caused by impact sound (collision sound).
In the prior art, in order to prevent shock pressure due to a sudden change in the operation of the hydraulic actuator, the pressure control valve or the name of the counter balance valve is used as a brake resistance valve on the oil actuator chamber side line of the hydraulic actuator in the hydraulic control circuit. It is equipped with a flow control valve or name called meter-out flow control valve. In addition, after detecting the hydraulic pressure generated in the oil pressure chamber side and oil pressure chamber side of the hydraulic actuator, or detecting the position of the hydraulic actuator, the pressure and position are converted into current and voltage, and then proportional. The flow rate is controlled by a control valve or servo control valve.
Further, as a measure against pressure fluctuation, a bladder type accumulator or a piston type accumulator filled with N2 gas is used to absorb the pressure fluctuation.

Hydraulic press stop control method and apparatus therefor Ram driving device in hydraulic punch press Method and apparatus for controlling pulsation pressure in hydraulic circuit of hydraulic cylinder Oil hammer control method and apparatus in two-pressure hydraulic circuit Oil hammer control method and apparatus in two-pressure hydraulic circuit Operation control device for ram cylinder device Japanese Patent Laid-Open No. 2000-202538 Method and apparatus for controlling cylinder / piston synchronization to reduce pressure peaks during deformation and / or precision punching in a press

Problems that the device tries to solve

In machinery in this field, it is common to use a hydraulic actuator having a characteristic of exerting a large force with a small volume, and to install and operate a hydraulic control device and hydraulic piping.
The hydraulic control device plays a role of giving various energy to the hydraulic fluid and controlling various hydraulic pressures. The hydraulic actuator plays a role of punching, crushing, and cutting a workpiece by directly or indirectly dropping or rotating a die or a blade depending on a driving method of the machine. The hydraulic piping is installed between the hydraulic control device and the hydraulic actuator and is responsible for the flow path of the hydraulic fluid that is a medium.
Because of the machinery having such characteristics, the external force applied to the hydraulic actuator varies greatly depending on the physical properties and shape of the workpiece to be processed by punching, crushing or cutting. Therefore, oil pressure generated in the押油chamber side line of the hydraulic actuator △ P _H varies according to the degree of the external force, and the set value of the pressure control valve and the maximum value thereof that is equipment pressure line of the hydraulic control device Become. Although varied by the pressure characteristics of the pressure control valve, hydraulic fluid as the hydraulic power △ P _H is high oil pressure is to be scavenge the tank line from the tank port of the pressure control valve, the lack of that amount Therefore, the hydraulic actuator operates at a low speed. However, as soon as punching or crushing and cutting finished, the operation of the hydraulic actuator suddenly changes from low speed to high speed, oil pressure △ P _H of押油chamber side line of the hydraulic actuator is reduced instantaneously. On the other hand, an impact pressure that is several times larger than the set value of the pressure control valve is generated in the oil pulling chamber side line of the hydraulic actuator. Also, in the process of propagation of the pressure wave converted from the impact pressure, it collides with part of the hydraulic piping and hydraulic control valve, so the welded part of the pipe joint constituting the hydraulic piping and the valve body of the hydraulic control valve, etc. Cracks, damage to the support that supports the piping, and so on. Moreover, it was also troubled by abnormal noise caused by impact sound (collision sound).
Attempts to buffer the impact pressure that causes the above-described problems and the impact force and impact sound (collision sound) caused by the propagation of the pressure wave converted from the impact pressure are prior solutions and techniques. More well known.
In many of the methods and technologies, the pressure control valve or the counter balance valve is used as a brake resistance valve in the oil chamber side line of the hydraulic actuator in the hydraulic control circuit in order to prevent impact pressure due to sudden changes in the hydraulic actuator's operation. In other words, it is equipped with a flow control valve, also called the meter-out flow control valve. In other words, the above-described hydraulic control valves are utilized to perform brake control to attenuate the impact pressure due to a sudden change in the operation of the hydraulic actuator. In addition, after detecting the hydraulic pressure generated in the oil pressure chamber side and oil pressure chamber side of the hydraulic actuator, or detecting the position of the hydraulic actuator, the pressure and position are converted into current and voltage, and then proportional. The flow rate is controlled by a control valve or servo control valve. Further, as a countermeasure against pressure fluctuation, a bladder type accumulator or a piston type accumulator filled with N 2 gas is used to absorb the pressure fluctuation.
However, the pressure control valve aka as a brake resistor valve引油chamber side line of the hydraulic actuator also called counterbalance valve, the case of equipment, the weight W is added to the hydraulic Akuchuta an area A _R of the引油chamber side it is necessary to more than the value of dividing the oil pressure △ P _R (Patent Document 1). Since the value of the oil pressure △ P _R is the offset relationship with its own weight W, in the balance between the own weight W to the set value of the pressure control valve to a value below than oil pressure △ P _R is naturally lowered collapses is there.
However, more must be done to brake control, the pressure control valve aka also called counterbalance valve, it is necessary to set a value greater than the value of the oil pressure △ P _R a.
In this case, there is a disadvantage that processing power for punching and crushing and cutting of the workpiece rise value component of the hydraulic force △ P _R, decreases.
A method of damping the impact pressure by installing a flow control valve or a meter-out flow control valve and performing brake control is also common. However, since the flow rate control valve and the flow rate control switching valve are of the spool type flow rate control system, the impact force accompanying the impact pressure is applied to the spool, and the impact force is applied to the valve body rather than the effect as brake control. For this reason, the damping effect of impact pressure is small (Patent Documents 3, 4 and 5).
However, the adjustment of the meter-out flow control valve has a drawback that the speed at which the brake control is desired is not achieved because the flow rate opening of the meter-out flow control valve is set in accordance with the rapid drop or rotation of the hydraulic actuator.
In recent years, logic valves have been developed and actively adopted. This valve is a two-port valve that opens and closes a check valve by operating a pressure signal on a pilot line. By controlling the pressure signal, the valve functions as a multi-function valve for direction, flow rate, and pressure.
Unlike the above-described spool type flow rate control method, the flow rate logic valve used has a small cushion function on the poppet surface that receives impact pressure, so that it is somewhat relaxed. However, since the flow rate opening of the flow rate logic valve is set in accordance with the rapid lowering of the hydraulic actuator and the speed at the time of rotation even in the flow rate logic valve, there still remains a drawback that the opening level for brake control is not achieved.
Control methods that take these disadvantages into account are used in precision presses and the like. It detects the hydraulic pressure generated in the hydraulic actuator's oil chamber side and oil chamber side line, detects the position of the hydraulic actuator, converts the pressure and position into current and voltage, The flow rate is controlled by a servo valve (Patent Documents 5 and 6).
The biggest problem of this problem is that the impact pressure generated in the oil pulling chamber side line of the hydraulic actuator is constant because the position where the mold and the tool hit each time varies depending on the work and the physical properties and shape of the work to be processed are different. It is not to become.
Patent Document 2 discloses an invention that eliminates an oil hammer sound (impact sound caused by impact pressure) when the piston of the hydraulic actuator is lowered. However, the invention has an effect only in the vicinity of the upper end of the hydraulic actuator. Similarly, Patent Document 3 is an invention that eliminates an oil hammer sound (impact sound caused by impact pressure) generated due to the structure of the upper end portion of the hydraulic actuator.
As a countermeasure against pressure fluctuation, a method of absorbing pressure fluctuation can be taken by using a bladder type accumulator filled with N2 gas or a piston type accumulator, but the oil pressure related to the hydraulic control device in this field ranges from the specified oil pressure to the impact pressure. Because it is a very wide pressure vessel that uses high-pressure gas, it is a reality that it is not utilized because of the difficulty in applying and maintaining laws such as the High-Pressure Gas Safety Act and Type 2 Pressure Vessels. . Patent Document 7 is an invention using an accumulator.
Prior solutions and techniques tend to be performed in particular by associating hydraulic control equipment with electrical control. In addition, a complicated hydraulic circuit configuration is used to solve the problem. However, in the embodiment of the machinery in the field according to the present invention, it is the actual situation that a high-hydraulic hydraulic control device, hydraulic piping and support are made robust and a passive method is taken to prevent breakage. Therefore, the present invention was made in view of this situation.

Means for solving the problem

  Therefore, in order to solve the above problems, the present invention particularly relates to a hydraulic control device used in a press machine, a waste material crusher, a cutting machine, etc., and a state of an external force applied during operation of the machinery. To buffer the impact pressure generated in the hydraulic fluid in the hydraulic actuator, hydraulic control device and hydraulic piping, and the impact force and impact sound (collision sound) caused by the propagation of the pressure wave converted from the impact force The purpose was to provide a hydraulic shock-absorbing valve.

In the above, in the hydraulic control device using the hydraulic actuator, the impact pressure generated by the state of the external force applied to the hydraulic actuator, the impact force and the impact sound caused in the process of propagation of the pressure wave converted from the impact pressure ( A hydraulic shock absorbing valve that cushions
A cylinder provided with a plurality of flow paths from the inner tube portion side fitted into the valve body toward the outer tube portion side;
A piston that is fitted to form an oil chamber of an A oil chamber and a B oil chamber in the cylinder and moves at a position in contact with the inner cylinder portion of the cylinder;
Screwed coaxially into an adjustment cover fitted in a spring receiving surface provided on an end surface portion of the piston on the B oil chamber side and a large-diameter fitting hole opened on the B oil chamber side of the valve body. A spring provided between the adjusting insert and
Since the piston moves toward the B oil chamber in the process of absorbing the impact pressure, an adjustment rod for adjusting the amount of movement;
An annular oil chamber having a diameter larger than the outer cylinder diameter of the cylinder, which connects the oil chamber of the A oil chamber and the B oil reservoir via the plurality of flow paths provided in the cylinder in the valve body,
A flow path through which hydraulic fluid can enter and exit from the annular oil chamber, and the valve body including a piping port on the B oil chamber side connected to the flow path,
The A oil chamber side flow path through which hydraulic fluid can enter and exit, and the A oil chamber side piping port connected to the flow path are provided.

  In the above, the shape of the piston on the A oil chamber side is a convex conical shape protruding toward the A oil chamber side, and the tip has a spherical shape.

  In the above, the shape of the piston on the A oil chamber side is a convex conical shape protruding toward the A oil chamber side, and the tip has a perpendicular right-angle plane with respect to the central axis.

  In the above description, the piston has a concave conical shape that is recessed from the end face of the A oil chamber on the piston.

  In the above, the shape of the piston forms a concave conical shape that is recessed from the end face of the A oil chamber on the A oil chamber side, and one or more connecting the A oil chamber and the B oil chamber to the back side thereof It has a flow path.

  In the above, the A oil chamber and the B are formed on the outer peripheral portion of the piston fitted in the inner cylindrical portion of the cylinder described in [0006] or [0007] or [0008] or [0009] or [0010]. A plurality of oil grooves that connect the oil chambers are provided.

Means for solving the problem

In particular, it relates to a hydraulic control device used in a press machine, a waste material crusher, a cutting machine, etc., and depending on the state of external force applied during the operation of the machinery, the hydraulic actuator, the hydraulic control device, and the hydraulic pressure in the hydraulic piping In order to buffer the impact pressure generated in the fluid and the impact sound (collision sound) generated in the process of propagation of the pressure wave converted from the impact pressure, the impact sound (impact Sound) is indispensable.
First, consider the hydraulic actuator line. The energy of the hydraulic fluid in the hydraulic chamber side of the hydraulic actuator (the energy obtained by adding the pressure energy, compression energy, velocity energy and position energy) is the resistance energy of the hydraulic fluid in the oil chamber side line (self-weight W and piping) than or hydraulic actuators and control equipment energy plus potential energy and pressure energy associated with compression energy and velocity energy sum of resistance to △ P _R divided by the area a _R of引油chamber side of the hydraulic actuator, such as a) If it is a little larger, the operation of the hydraulic actuator enters the process of processing the workpiece. Also, in the balanced process where the inertia of the hydraulic fluid filled in the hydraulic chamber side line of the hydraulic actuator and the inertia of the hydraulic fluid controlled by the pressure control and meter-out flow rate control of the oil extraction chamber side line are brake controlled Impact pressure does not occur. However, the external force applied to the hydraulic actuator varies greatly depending on the physical properties and shape of the workpiece while the die or the blade hits the workpiece and is punched, crushed and cut.
Therefore, oil pressure generated in the押油chamber side line of the hydraulic actuator △ P _H varies according to the degree of the external force, and the set value of the pressure control valve and the maximum value thereof that is equipment pressure line of the hydraulic control device Become. Further, since the operation of the hydraulic actuator varies the pressure characteristics of the pressure control valve, hydraulic fluid as the hydraulic power △ P _H is high oil pressure is to be oil discharge to the tank line from the tank port of the pressure control valve, Because it becomes insufficient, it becomes slow. That is, it can be seen that the energy (pressure energy, compression energy, velocity energy, and position energy) of the hydraulic fluid in the oil pressure chamber side line of the hydraulic actuator is mainly pressure energy and compression energy.
On the other hand, the resistance energy of the hydraulic fluid in the oil chamber side line of the hydraulic actuator is much smaller. However, as soon as punching, crushing, and cutting are completed, the external force disappears or becomes negative due to its own weight W. Therefore, the pressure energy and compression energy of the hydraulic fluid in the hydraulic chamber side of the hydraulic actuator are energy From the conservation law, it affects the hydraulic fluid in the oil chamber side of the hydraulic actuator instantly.
That is, the energy of the hydraulic fluid in the hydraulic chamber side line of the hydraulic actuator is instantaneously converted to the hydraulic fluid side of the oil chamber side line, and the area ratio of the hydraulic actuator, the inertia of the hydraulic fluid, and the operation of the hydraulic control valve Overlapping conditions such as delay result in several times the impact pressure. In addition, this impact pressure is converted into a pressure wave and propagates at a speed close to the speed of sound, and when it collides with a corner of a hydraulic pipe or a part of the inside of a hydraulic control valve (generates a collision sound or abnormal noise), it is reflected and attenuated. Is done.
In the hydraulic control valve, due to the generation of the instantaneous impact pressure described above, the differential pressure of each hydraulic control valve (the difference between the inlet pressure and the outlet pressure of the hydraulic fluid) increases, and more oil than the normal control flow rate. The amount will flow. Concomitantly hydraulic actuator suddenly changes from low speed to high speed, and pressure △ P _H of押油chamber side line decreases drastically.
Accordingly, in the present invention, a plurality of fitting holes having coaxial and different inner diameters are formed in the valve body, and a cover provided with a piping port is fitted into the small-diameter fitting hole on the A oil chamber side.
The cover has a flow path leading to the A oil chamber, and forms an oil chamber side line between the hydraulic actuator and the hydraulic shock absorbing valve. A large diameter fitting hole is inserted with a cylinder provided with a plurality of flow paths from the inner cylinder side toward the outer cylinder side. An inner cylinder diameter of the cylinder is larger than an inner diameter of a flow path leading to the A oil chamber provided in the cover. This is because the propagated pressure wave is disturbed by the cross-sectional area difference, and the various energies are attenuated. The cover may be integrated with the valve body, and this does not depart from the purpose, function and performance of the present invention.
In the cylinder, in order to form the oil chamber of the A oil chamber and the B oil chamber, a piston that slides at a position in contact with the inner cylinder portion of the cylinder is fitted, and the A oil chamber side of the piston The shape in FIG. 5 is, for example, a plane perpendicular to the central axis, or as in each of the embodiments described in [0007] or [0008] or [0009] or [0010]. In particular, the common point of the embodiments described in [0007], [0008], [0009] or [0010] is a conical shape. This is because the pressure wave propagated to the A oil chamber collides with the tapered surface portion of the conical shape and perturbs the pressure wave, thereby attenuating various energy of the hydraulic fluid and reducing the impact force. . That is, the impact force is the product of the hydraulic fluid mass m and the speed difference ΔV (V2−V1) per oil time difference Δt (t2−t1). Since the time difference Δt (t2−t1) can be taken in the conical tapered surface portion, the impact force is reduced.
At the same time, this means moves the piston to the B oil chamber side in order to relieve the shock pressure and the impact force generated when the pressure wave collides with the surface portion of the piston on the A oil chamber side. I try to let them. This is because pressure energy and compression energy can be absorbed more. In addition, a sliding length is set at a location where the piston is in contact with the inner cylindrical portion so that the piston can move stably during disturbance, and the piston is fitted to the inner cylindrical portion of the cylinder.
A spring installed in the B oil chamber is responsible for the movement of the piston.
The spring force of the spring is set to a value smaller than the impact force generated when a pressure wave collides with the surface portion of the piston on the side of the A oil chamber, and when no impact force or pressure wave is generated, Since it is necessary to restore to the position, the value that can be restored is also taken into consideration. The spring is provided on a spring receiving surface provided on an end surface portion of the piston on the B oil chamber side, and an adjustment cover fitted in a large-diameter fitting hole opened on the B oil chamber side of the valve body. Located between the coaxially screwed adjustment inserts.
By changing the screwing amount of the adjustment insert, the spring force is changed, and it is possible to adjust the buffering of pressure energy, compression energy, and impact force.
The adjustment insert is fixed with a large nut.
Since the piston moves due to a dynamic factor such as an impact force or a pressure wave generated when a pressure wave collides with the surface portion of the shape on the A oil chamber side, an adjustment rod is provided so as not to excessively move the piston. The amount of movement of the piston is adjusted.
The adjusting rod is inserted into the center hole of the adjusting insert, and has a screw on the side opposite to the B oil chamber side so that the movement can be adjusted. That is, the amount of movement of the piston is between the spring receiving surface provided on the end surface portion of the piston on the B oil chamber side and the end surface of the adjusting rod on the B oil chamber side. The adjustment rod is fixed with a small nut.
The cylinder is provided with a plurality of flow paths from the inner cylinder part side to the outer cylinder part side. A plurality of oil grooves connecting the A oil chamber and the B oil chamber to the outer peripheral portion of the piston, and the A oil chamber on the back side of the concave conical shape recessed from the A oil chamber side end surface of the piston. The reason for adding one or a plurality of flow paths, for example, to the B oil chamber is that when the hydraulic fluid passes through the plurality of flow paths or the plurality of oil grooves, the velocity energy increases. This is because the pressure energy decreases. Since the energy of the hydraulic fluid transmitted to the A oil chamber is mainly pressure energy and compression energy, it is particularly significant to reduce the pressure energy.
The valve body has a left end on the A oil chamber side and a right end on the B oil chamber side of the plurality of flow paths provided in the cylinder having a diameter larger than the outer cylinder diameter of the cylinder inserted. There is an annular oil chamber that is longer than the length to be tied. This is because the hydraulic actuator is moved up and down or rotated left and right through the plurality of flow paths provided on the A oil chamber side and the B oil chamber side of the cylinder, and the annular oil chamber. The hydraulic fluid in the A oil chamber is provided to the B oil chamber, or the hydraulic fluid in the B oil chamber needs to be guided to the A oil chamber.
As a result, the annular fluid chamber is filled with hydraulic fluid, so that the pressure difference of the valve body and the cylinder and the hydraulic fluid, and the cushioning effect due to the air content of the hydraulic fluid including 5 to 9 percent, Attenuation of impact sound and abnormal sound (sound wave) in propagation can also be expected.
By providing a piping port on the A oil chamber side and a piping port on the B oil chamber side of the valve body to allow the hydraulic fluid to enter and exit, the effect and function of the hydraulic shock buffer valve are achieved.
The adjustments for damping and buffering the energy, impact force, and impact sound (collision sound) described above are the adjustment function of the hydraulic impact buffer valve, that is, the change adjustment of the spring length and the change adjustment of the movement amount of the piston. In addition, the oil pressure (resistance oil pressure or back pressure) in the flow path leading to the annular oil chamber, the B oil chamber, and the B oil chamber is changed and adjusted. That is, by providing the hydraulic control valve, the buffering capacity of the hydraulic shock buffer valve can be expanded. For this purpose, a pressure control valve or a flow rate adjusting valve is installed in the flow path line leading to the B oil chamber, the pipe diameter is restricted to the oil drain line (tank line), or a throttle mechanism is added. Therefore, a further buffering effect can be expected.
Further, for example, even when an impact pressure is generated on the pressure chamber side of the hydraulic actuator by a mechanical drive system other than those described so far, if the hydraulic shock buffer valve is installed in the pressure chamber side line, the hydraulic shock buffer valve Is fully effective. In this way, the installation of the hydraulic shock buffer valve does not require a complicated hydraulic control circuit configuration, and simplification can be expected.
As described above, in particular, it relates to hydraulic control devices used in press machines, waste material crushers, cutting machines, etc., and is related to cracks in pipe joint welds and hydraulic control valves that constitute hydraulic pipes, pipe support, etc. The shock pressure generated in the hydraulic fluid that causes damage, impact sound (impact sound), and the impact force and impact sound (impact sound) generated in the process of propagation of the pressure wave converted from the impact pressure are buffered. The purpose and provision of the hydraulic shock absorbing valve can be achieved.

Example of device

  Hereinafter, a hydraulic shock absorbing valve according to the present invention will be described with reference to the drawings as appropriate.

In the drawings to be referred to, FIG. 1 is a sectional view of a first embodiment. FIG. 2 is a sectional view of the second embodiment. FIG. 3 is a sectional view of the third embodiment. FIG. 4 is a sectional view of the fourth embodiment. FIG. 5 is a cross-sectional view including a piston 7 provided with, for example, a single channel according to the fifth embodiment. FIG. 6 is a cross-sectional view of the piston 7 having a plurality of flow paths, for example, as viewed from the line AA in FIG. 7 according to the fifth embodiment.
FIG. 7 is a side view of a piston 7 having a plurality of flow paths, for example, according to the fifth embodiment. FIG. 8 is a side view in which the sixth embodiment is applied to each piston 7 of the first embodiment, the second embodiment, the third embodiment, or the fourth embodiment. FIG. 9 is a side view of the piston 7 according to the sixth embodiment applied to the piston 7 having a plurality of flow paths, for example, according to the fifth embodiment. FIG. 10 is a sectional view taken along line AA of FIG. 8 in which the sixth embodiment is applied to the first embodiment. FIG. 11 is a sectional view taken along line AA of FIG. 8 in which the sixth embodiment is applied to the second embodiment. 12 is a sectional view taken along line AA of FIG. 8 in which the sixth embodiment is applied to the third embodiment. FIG. 13 is a sectional view taken along line AA of FIG. 8 in which the sixth embodiment is applied to the fourth embodiment. FIG. 14 is a cross-sectional view of the sixth embodiment as viewed from the line AA in FIG. FIG. 15 is a hydraulic control circuit diagram of an example using the hydraulic shock absorbing valve in the present invention. A hydraulic control circuit for controlling the hydraulic actuator 17 and a hydraulic control circuit for the pump and tank are omitted.
The reference numerals in FIGS. 1 to 15 are the same regardless of all the embodiments.

In FIG. 1 showing the first embodiment of the hydraulic shock absorbing valve of the present invention, a fitting hole having a small diameter on the A oil chamber 5 side and a large diameter on the B oil chamber 6 side is formed coaxially with the valve body 2. A cover 16 having a piping port 16b attached to the small diameter fitting hole on the oil chamber 5 side is fitted and fastened with a bolt. The cover 16 is provided with a passage hole 16a that continues to the passage of the piping port 16b and communicates with the A oil chamber 5, and is formed between the oil suction chamber 19 of the hydraulic actuator 17 and the hydraulic shock absorbing valve 1. 15, an oil chamber side line 19 a is formed. For example, the valve body 2 and the cover 16 may have an integrated structure, which does not depart from the purpose, function, and performance of the present invention.
A large diameter fitting hole that is coaxially opened on the B oil chamber 6 side of the valve body 2 is fitted with a cylinder 4 having a plurality of flow paths 3 from the inner cylinder side toward the outer cylinder side. . In addition, the process of the some flow path 3 is constructed toward the inner cylinder part side from the outer cylinder part side. In the plurality of flow paths 3, the A oil chamber 5 side is denoted by 3 a and the B oil chamber 6 side is denoted by 3 b.
A fitting hole having an inner diameter related to the outer diameter of the piston 7 is formed in the inner cylinder portion of the cylinder 4 up to the original position 7 a of the piston 7, and the further coaxial hole forming the A oil chamber 5 is the piston 7. The diameter is smaller than the inner diameter related to the outer diameter. In other words, a step is provided to stop the piston 7 at the original position 7a. Further, the above-described coaxial hole has a larger diameter than the channel hole 16a communicating between the channel of the piping port 16b and the A oil chamber 5, and the step is not provided with a taper. This is to prevent turbulent flow of the hydraulic fluid.
The cylinder 4 is arranged so that the end face of the cylinder 4 on the B oil chamber 6 side coincides with the tip of the spigot of the adjustment cover 8 fitted in the valve body 2 so as not to move.
The sliding length and the fitting dimension of the piston 7 fitted in the fitting hole of the inner cylinder 4 are the oil B when absorbing the pressure energy and compression energy of the oil chamber side line 19a and when the pressure wave is disturbed. It has a length that encourages stability when moving to the chamber 6 side.
Further, a spring receiving surface 7b is provided at an end surface portion of the piston on the B oil chamber 6 side, and holds one side of the spring.
The adjustment cover 8 is formed with a fitting hole in the vicinity of the outer diameter of the piston 7, a coaxial female screw -1 is machined on the opposite side of the cylinder 4, and the adjustment cover 8 is fastened to the valve body 2 with a bolt. . Further, at the center of the adjustment cover 8, the outer diameter of the piston 7 and the outer diameter related to the fitting hole in the vicinity, the male screw -1 that matches the coaxial female screw -1 on the opposite side of the cylinder 4, An adjustment insert 9 provided with a coaxial fitting hole having a smaller diameter than the inner diameter of the spring 10 and a female screw -2 slightly larger than the small-diameter coaxial fitting hole on the opposite side of the spring 10 is screwed. For example, a width across flats is applied to the end of the male screw 1 so that the adjustment insert 9 can move. With this structure, the spring force of the spring 10 can be adjusted. The adjustment insert 9 is fixed with a large nut 12.
The adjusting rod 11 is provided with an outer diameter related to the small-diameter fitting hole opened at the center of the adjusting insert 9 and a male screw-2 that matches the female screw-2. Further, the end of the male screw-2 is provided with, for example, a hexagonal head, a hexagonal hole, a square head, and a two-sided width so that the adjusting rod 11 can move. With this structure, the amount of movement of the piston 7 is between the spring receiving surface 7b provided on the end surface portion of the piston 7 on the B oil chamber 6 side and the end surface of the adjustment rod 11 on the B oil chamber 6 side. The adjustment rod 11 is fixed with a small nut.
The valve body 2 has a diameter larger than the outer cylinder diameter of the inserted cylinder 4 and the left ends of the plurality of flow paths 3a applied to the cylinder 4 on the A oil chamber 5 side, and the B oil of the plurality of flow paths 3b. There is an annular oil chamber 14 which is longer than the length connecting the right ends on the chamber 6 side. Thus, the hydraulic fluid in the A oil chamber 5 can be guided to the B oil chamber 6 or the hydraulic fluid in the B oil chamber 6 can be guided to the A oil chamber 5 via the annular oil chamber 14. Moreover, the annular oil chamber 14, the flow path 15, and the B oil chamber 6 side piping port are provided.
Thus, the first embodiment of the hydraulic shock absorbing valve of the present invention is configured.

As for the hydraulic shock absorbing valve of the present invention, in FIG. 2 showing the second embodiment, the shape of the piston 7 on the A oil chamber 5 side is a convex conical shape protruding to the A oil chamber 5 side, and its tip is Sphere. The second embodiment of the present invention is the same as the first embodiment except that the piston 7 of the first embodiment is changed to the piston 7 of the second embodiment.
Thus, the second embodiment of the hydraulic shock absorbing valve of the present invention is configured.

As for the hydraulic shock absorbing valve of the present invention, in FIG. 3 showing the third embodiment, the shape of the piston 7 on the A oil chamber 5 side is a convex conical shape protruding toward the A oil chamber 5 side, and the tip is The plane is perpendicular to the central axis. The third embodiment of the present invention is the same as the first embodiment except that the piston 7 of the first embodiment is changed to the piston 7 of the third embodiment.
Thus, the third embodiment of the hydraulic shock absorbing valve of the present invention is configured.

In the hydraulic shock absorbing valve of the present invention, in FIG. 4 showing the fourth embodiment, the shape of the piston 7 on the A oil chamber 5 side is a concave conical shape recessed from the end surface on the A oil chamber 5 side. The fourth embodiment of the present invention is the same as the first embodiment except that the piston 7 of the first embodiment is changed to the piston 7 of the fourth embodiment.
Thus, the fourth embodiment of the hydraulic shock absorbing valve of the present invention is configured.

5, 6, and 7 showing the fifth embodiment of the hydraulic shock absorbing valve of the present invention, FIG. 5 shows, for example, a single flow path of the fifth embodiment through the end surface of the piston 7 on the side of the oil chamber 5. It is applied to the back side of the more concave concave conical shape and connects the A oil chamber 5 and the B oil chamber 6.
The fifth embodiment of the present invention is the same as the first embodiment except that the piston 7 of the first embodiment is changed to the piston 7 having a single flow path of the fifth embodiment, for example. Identical. In FIG. 6, for example, a plurality of flow paths in the fifth embodiment are provided on the back side of the concave conical shape recessed from the end face of the A oil chamber 5 of the piston 7, and the A oil chamber 5 and the B oil chamber 6 are connected. Yes.
The fifth embodiment of the present invention is the same as that of the first embodiment except that the piston 7 of the first embodiment is changed to the piston 7 having a plurality of flow paths, for example, of the fifth embodiment. Identical. FIG. 7 shows a side surface of the piston 7 having a plurality of flow paths, for example, according to the fifth embodiment.
Thus, the fifth embodiment of the hydraulic shock absorbing valve of the present invention is configured.

8, 9, 10, 11, 12, 13, and 14 showing the sixth embodiment of the hydraulic shock absorbing valve of the present invention, FIG. 8 shows the first embodiment or the second embodiment. An oil groove having a shape having a width and depth and a length connecting the A oil chamber 5 and the B oil chamber 6 to the outer peripheral portion of each piston 7 of the embodiment, the third embodiment, or the fourth embodiment. Is a side view of the piston 7 of the sixth embodiment, which is equally divided on the circumference. In the sixth embodiment of the present invention, each piston 7 of the first embodiment, the second embodiment, the third embodiment, or the fourth embodiment is changed to the piston 7 of the sixth embodiment. The rest is the same as in the first embodiment except for the above. FIG. 9 shows an oil groove having a shape having a width and depth and a length connecting the A oil chamber 5 and the B oil chamber 6 to the outer peripheral portion of the piston 7 having a plurality of flow paths, for example, in the fifth embodiment. Is a side view of the piston 7 of the sixth embodiment, which is equally divided on the circumference. The sixth embodiment of the present invention is the same as the first embodiment except that the piston 7 of the fifth embodiment is changed to the piston 7 of the sixth embodiment. FIG. 10 shows a sixth embodiment in which the piston 7 of the first embodiment is changed to the piston 7 having an oil groove of the sixth embodiment. FIG. 11 shows a sixth embodiment in which the piston 7 of the second embodiment is changed to the piston 7 having the oil groove of the sixth embodiment. FIG. 12 shows a sixth embodiment in which the piston 7 of the third embodiment is changed to the piston 7 having the oil groove of the sixth embodiment. FIG. 13 shows a sixth embodiment in which the piston 7 of the fourth embodiment is changed to the piston 7 having the oil groove of the sixth embodiment. FIG. 14 shows a sixth embodiment in which the piston 7 having a plurality of flow paths, for example, in the fifth embodiment is changed to the piston 7 having an oil groove of the sixth embodiment.
Thus, the sixth embodiment of the hydraulic shock absorbing valve of the present invention is constituted.

FIG. 15 shows a general hydraulic control circuit diagram for operating the hydraulic actuator in the hydraulic shock absorbing valve of the present invention. The configuration of the control valve and the like for changing and adjusting the oil pressure (resistance oil pressure or back pressure) in the annular oil chamber 14, the B oil chamber 6 and the flow path leading to the B oil chamber 6 is omitted.

The present invention has been exemplified as a hydraulic shock buffer valve related to a hydraulic control device used in a press machine, a waste material crusher and a cutting machine, but the present invention is not limited to this. Of course, the same advantage can be obtained even when used in various fields of machinery in which impact pressure is generated in the control device.

Effect of device

As described above, since the hydraulic shock absorbing valve of the present invention has a plurality of flow paths in the shape and valve structure for disturbing the hydraulic fluid, the generated shock pressure and the pressure wave converted from the shock pressure are provided. It is possible to buffer the impact force and the impact sound (collision sound) caused in the process of propagation. Due to the above, problems such as cracks in the welds of pipe joints that make up hydraulic piping, cracks in the valve body of hydraulic control valves, damage to the support that supports the piping, and abnormal noise caused by impact noise (collision noise) Can be expected and simplification can be expected without the need for a complicated hydraulic control circuit configuration.

FIG. 2 is a cross-sectional view of the first embodiment. These are sectional views of the second embodiment. These are sectional views of the third embodiment. These are sectional drawings of the 4th example. FIG. 9 is a cross-sectional view including a piston 7 provided with, for example, a single channel according to the fifth embodiment. These are sectional drawings seen from the AA line of Drawing 7 of piston 7 which gave a plurality of channels of the 5th example, for example. These are the side views of the piston 7 which gave the some flow path of the 5th Example, for example. These are the side views which gave the 6th example to each piston 7 of the 1st example or the 2nd example or the 3rd example or the 4th example. These are the side views of the piston 7 which applied the 6th Example to the piston 7 which gave the some flow path of the 5th Example. These are sectional drawings seen from the AA line of FIG. 8 which applied the 6th example to the 1st example. These are sectional drawings seen from the AA line of FIG. 8 which applied the sixth embodiment to the second embodiment. These are sectional drawings seen from the AA line of FIG. 8 which applied the sixth embodiment to the third embodiment. These are sectional drawings seen from the AA line of FIG. 8 which applied the sixth embodiment to the fourth embodiment. FIG. 10 is a cross-sectional view of the sixth embodiment as viewed from the line AA in FIG. These are the hydraulic control circuit diagrams of the example using the said hydraulic shock buffer valve in this invention.

DESCRIPTION OF SYMBOLS 1 Hydraulic shock buffer valve 2 Valve body 3 The some flow path provided in the cylinder 4 3a The flow path by the side of A oil chamber 5 3b The flow path by the side of B oil chamber 6 3c The flow path by the back side of concave cone shape 4 Tube 5 A Oil chamber 6 B Oil chamber 7 Piston 7a Original position 7b Spring receiving surface 7c Oil groove 8 Adjustment cover 9 Adjustment insert 10 Spring 11 Adjustment rod 12 Large nut 13 Small nut 14 Annular oil chamber 15 Flow path 15a B Oil chamber 6 Piping port 16 on the side 16a Flow passage hole 16b Piping port 17 on the A oil chamber 5 side Hydraulic actuator 18 Oiling chamber 18a Oiling chamber side line 19 Oiling chamber 19a Oiling chamber side line

Claims (6)

In a hydraulic control device using a hydraulic actuator, the impact pressure generated by the external force applied to the hydraulic actuator and the impact force and impact sound (impact sound) caused by the propagation of the pressure wave converted from the impact pressure And a hydraulic shock absorbing valve for buffering,
A cylinder provided with a plurality of flow paths from the inner tube portion side fitted into the valve body toward the outer tube portion side;
A piston that is fitted to form an oil chamber of an A oil chamber and a B oil chamber in the cylinder and moves at a position in contact with the inner cylinder portion of the cylinder;
Screwed coaxially into an adjustment cover fitted in a spring receiving surface provided on an end surface portion of the piston on the B oil chamber side and a large-diameter fitting hole opened on the B oil chamber side of the valve body. A spring provided between the adjusting insert and
Since the piston moves toward the B oil chamber in the process of absorbing the impact pressure, an adjustment rod for adjusting the amount of movement;
An annular oil chamber having a diameter larger than the outer cylinder diameter of the cylinder connecting the oil chamber of the A oil chamber and the B oil chamber via a plurality of flow paths provided in the cylinder in the valve body;
A flow path through which hydraulic fluid can enter and exit from the annular oil chamber, and the valve body including a piping port on the B oil chamber side connected to the flow path,
A hydraulic shock absorbing valve comprising a flow path on the A oil chamber side through which hydraulic fluid can enter and exit, and a piping port on the A oil chamber side connected to the flow path. 2. The hydraulic shock absorbing valve according to claim 1, wherein a shape of the piston on the A oil chamber side is a convex conical shape protruding toward the A oil chamber side and a tip is spherical. 2. The hydraulic shock absorbing valve according to claim 1, wherein a shape of the piston on the A oil chamber side is a convex conical shape protruding toward the A oil chamber side, and a tip thereof has a perpendicular right-angle plane with respect to a central axis. 2. The hydraulic shock absorbing valve according to claim 1, wherein the piston has a concave conical shape that is recessed from an end face on the A oil chamber side of the piston. A shape of the piston on the side of the A oil chamber forms a concave conical shape that is recessed from the end surface of the A oil chamber, and one or a plurality of flow paths connecting the A oil chamber and the B oil chamber on the back side. The hydraulic shock absorbing valve according to claim 1. 6. The hydraulic shock absorber according to claim 1, 2, 3, 4, or 5, having a plurality of oil grooves connecting the A oil chamber and the B oil chamber in an outer peripheral portion of the piston fitted into an inner cylinder portion of the cylinder. valve.

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