JPH0957655A - Portable type hydraulic processing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To omit final adjustment due to additional oil supply and suppress deterioration of the restoring force resulting from a long time of storage, etc. SOLUTION: An accommodation part 46 is formed in communication to the atmosphere, and therein a flexible oil bag 42 is accommodated fast while the inside is in communication with the oil flow path leading from a second chamber 26b to a reserver 22. Fixation of the oil bag 42 to the accommodation part 46 is made while a holder 50 is attached by screwing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applicable to a machining jig which is interlocked with a piston under the sliding of the piston accompanying the pressure-feeding of pressurized oil to the corresponding chamber on the starting side defined in the cylinder. The present invention relates to a portable hydraulic processing machine that performs desired machining.

[0002]

2. Description of the Related Art For example, in construction sites, civil engineering sites, etc., mechanical processing such as cutting and bending of reinforcing bars and pipes and perforation of steel plates and shaped steels is required as required. These types of machining are performed by various portable hydraulic type processing machines called punchers and the like.

In this type of hydraulic processing machine, for example, a piston in which a piston rod is extended to the front end side of a piston head is slidably arranged in a cylinder, and the inside of the cylinder is moved by the piston head. A first chamber on the starting side and a second chamber on the returning side are defined separately.

An oil tank called a reservoir is communicated with the first chamber of the cylinder through a flow path in which the pump mechanism is arranged, and the oil under pressure is supplied to the first chamber under the operation of the pump mechanism. The piston is slid (advanced) in the starting direction by pressure feeding, and under this piston advancement, desired machining according to the machining jig interlocked with the piston is performed on a predetermined workpiece. The hydraulic processing machine of is configured.

Here, since the piston rod is extended into the second chamber, the starting direction (forward movement) of the piston,
There is a difference in the maximum volumes of the first chamber and the second chamber when the piston slides in the return direction (retraction), that is, the overall volume of the oil circulation path connecting the first chamber, the second chamber and the reservoir. . Such volume fluctuation of the oil circulation path causes negative pressure due to sliding of the piston, making smooth sliding of the piston difficult.Therefore, in the hydraulic processing machine, negative pressure due to volume fluctuation is generated. Must be prevented.

Therefore, in this type of hydraulic processing machine, a flexible air bag is usually provided in the oil circulation path as a negative pressure prevention mechanism to prevent the generation of negative pressure due to sliding of the piston. ing. An air bag is normally opened to the atmosphere, for example, the second chamber,
It is arranged in the oil flow path between the reservoirs. Then, by contracting or restoring to the original shape in accordance with the volume variation of the second chamber, the overall volume of the oil circulation path including the oil flow path between the second chamber and the reservoir is made constant. , The airbag is constructed.

[0007]

By the way, in this type of portable hydraulic processing machine, usually, after the completion of the whole assembly, the return position of the piston which is the initial position, that is, the second position.
At the maximum volume of the chamber, oil is filled into the flow passage from a predetermined oil filling port. However, at the piston return position, oil must be filled up to the contracted state of the airbag, so in the known configuration, after normal lubrication,
A final adjustment by so-called additional oiling is required, in which the piston is forcibly pulled out from the return position.

Since the final adjustment by such additional oiling complicates the work, the workability is unavoidably deteriorated.

Further, at the piston return position where the volume of the second chamber is maximum, the overall volume of the oil circulation path is small, so that the airbag is kept in a contracted state and the first chamber At the piston forward position (starting position) where the volume is maximum, the volume of the oil circulation path is large, and the airbag is restored to its original shape.

That is, the piston is in the return position (initial position).
Since the airbag is in a contracted state when the hydraulic processing machine that is on standby is not in operation, the compressed state of the airbag is often continued for a long time when the hydraulic processing machine is stored. . However, the airbag is a flexible material,
When this flexible material is kept in a contracted state for a long period of time, deterioration of the restoring force is likely to be caused due to aging of the material itself.
The deterioration of the restoring force in the airbag hinders the smooth flow of oil accompanying the movement of the piston, which may make smooth sliding of the piston difficult.

An object of the present invention is to provide a portable hydraulic processing machine which omits final adjustment by additional oiling and suppresses deterioration of restoring force due to long-term storage or the like.

[0012]

In order to achieve this object, in the present invention, a flexible oil bag is provided in place of a conventional air bag, and an oil bag is contracted and restored to restore the oil. The volume of the circulation path of the is being made constant.

That is, according to the present invention, the hollow accommodating portion is formed so as to communicate with the atmosphere, and the flexible oil bag communicates the inside with the oil passage between the second chamber and the reservoir. Is arranged and fixed in the storage part.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings.

As shown in FIG. 1, a portable hydraulic machine 10 according to the present invention comprises a housing 12, a casing 14 consisting of a front half 14-1 and a rear half 14-2, and a motor housing 16. They are assembled as shown by bolting or the like between them via seal packing or the like.

In this type of hydraulic processing machine 10, for example, a motor (not shown) whose drive is controllable under the operation of the switch means 18 provided on the handle 16a of the motor housing 16 is provided in the motor housing. The output shaft 20 of the motor housed and extended from the motor housing 16 is rotatably inserted into a hollow reservoir (oil tank) 22 provided in the rear half 14-2 of the casing 14. Has been done.

The reservoir 22 is capable of storing oil, and the first half 14
-1, and a pump mechanism 24 that supplies the oil accumulated in the reservoir in a predetermined direction under pressure is provided, for example, at an intermediate position of the flow path 25 communicating with the reservoir. ing.

Further, as shown in FIG. 1, a substantially cylindrical cylinder 26 is provided between the front half portion 14-1 of the casing and the housing 12.
And a piston 28 integrally formed with a piston rod 28a extending forward is disposed slidably in the cylinder. Then, the inside of the cylinder 26 is divided into a first chamber 26a on the starting side and a second chamber 26b on the returning side by the piston head 28b of the piston, and the reservoir 22 via the flow path 25 in which the pump mechanism 24 is arranged. Are in communication with the first chamber.

In such a structure, the pump mechanism 24
When the pressurized oil is sent from the reservoir 22 to the first chamber 26a under the operation of, the piston 28 is slid (advanced) in the cylinder 26 in the starting direction, that is, to the left in the drawing. . Then, this type of hydraulic processing machine 10 is configured so that the machining jig 30 is actuated as the piston 28 moves forward to perform desired machining according to the machining jig (see FIG. 2). .

As shown in FIG. 1, in this type of hydraulic processing machine 10, for example, a return spring 32, which is a compression coil spring, allows the piston 28 to be biased toward the initial position in the second chamber. It is wound around the piston rod 28a. That is, the piston 28 is capable of sliding (retracting) from the forward movement position to the initial return position under the biasing force of the return spring 32.

The second chamber 26b is communicated with the reservoir 22 via, for example, the flow path 33, and oil is generated between the second chamber and the reservoir in accordance with volume fluctuation of the second chamber due to sliding of the piston 28. It is available for distribution at.

Here, as can be seen from FIG. 1, in the embodiment of the present invention, a pair of movable cutters 30-
1, a portable hydraulic processing machine 10 is exemplified as a reinforcing bar cutter using the fixed cutter 30-2 as the processing jig 30. In such a hydraulic processing machine (rebar cutter) 10, the movable cutter 30-1 is fixed to the tip of the piston rod 28a, and the corresponding fixed cutter 30-2 is attached to the housing 12.
A work piece such as a reinforcing bar is placed in the space 34 between the fixed cutter and the movable cutter at the initial position of the piston 28 as shown in the figure, which is fixed to face the movable cutter.

For example, a relief valve 36 is provided on the piston head 28b. The relief valve 36 has a head 38 that moves with the movement of the valve rod 38 in the axial direction when the piston 28 advances to a predetermined position inside the cylinder 26.
It is configured to open the relief hole 40 of the piston head under the separation of a (see FIG. 2).

When the pressurized oil is sent to the first chamber 26a, the head 38a of the valve rod comes into close contact with the opening of the relief hole 40 under the pressure acting in the first chamber. The closed state of the relief valve 36 is maintained.

By the way, in the hydraulic processing machine 10 of this type, the first chamber 26a, the volume corresponding to the volume of the piston rod 28a exposed inside the second chamber 26b,
The maximum volume of the second chamber, ie the first chamber, the second
Differences occur in the overall volume of the oil circulation path connecting the chamber and the reservoir 22.

Therefore, in this type of hydraulic processing machine 10, normally, the overall volume is made constant by shrinking the air bag arranged in the oil circulation path and restoring it to its original shape. In the present invention, as shown in FIG. 1, not the airbag but the flexible oil bag 42 capable of accommodating the oil communicates with the inside of the oil passage between the second chamber 26b and the reservoir 22. It is arranged.

In the embodiment of the present invention,
An oil bag 42 is provided between the second chamber 26b and the flow path 33 so as to communicate with each other.

The oil bag 42 is formed of, for example, an oil-resistant synthetic rubber material or the like into a bag shape having one end as an open end. In the present invention, the oil bag 42
A flange 44 is integrally formed at the open end of the.

The oil bag 42 is housed in the housing portion 46 of the housing 12, for example. The storage portion 46 is formed, for example, as a substantially cylindrical hollow portion having one end opened to the outside, and through the communication hole 48 bored in the bottom wall 46a, the oil between the second chamber 26b and the reservoir 22 is stored. It is in communication with the distribution channel. That is, the storage section 46 is formed so as to communicate individually with the circulation paths of the atmosphere and oil.

Here, it is preferable that the storage portion 46 is formed so as not to have a stepped portion on the opening end side that hinders the storage of the oil bag 42 therein. With such a configuration, as will be described later, since the oil bag 42 can be stored and removed via the open end of the storage portion 46, workability in storing and replacing the oil bag is improved.

Since the communication hole 48 in the bottom wall of the storage portion is provided so that the remaining bottom wall 46a serves as a step at the boundary between the storage portion 46 and the oil flow passage, its diameter is The flange 44 of the oil bag is formed so as to be engageable with the stepped portion, for example, having a smaller diameter than the opening 42a of the oil bag.

Under the alignment of the opening 42a with the communication hole 48, the oil bag 42 blocks the communication between the atmosphere and the oil distribution path while allowing the oil communication path to communicate with the inside. And is stored and arranged in the storage section 46. The cutoff of the communication between the atmosphere and the oil flow path is performed, for example, by the storage section bottom wall 46.
It is performed under the close contact of the flange 44 with respect to a.

The fixing of the oil bag 42 inside the storage portion 46 is performed by the holder 50, for example. holder
For example, 50 is molded from a synthetic resin material or the like into a bottomed tubular shape that allows the open end of the oil bag 42 to be engaged with the flange 44 of the oil bag by covering the oil bag 42.

A vent hole 52, through which air can flow, is previously formed in the bottom of the holder 50. In other words, the inside of the holder 50, and by extension, the circumference of the oil bag 42
It is open to the atmosphere via 52.

The holder 50 is inserted into the storage portion 46 from the opening end 50a after the oil bag 42 is stored in the storage portion 46. Here, the holder 50 and the storage 46 are
54 and a female screw 56 are respectively provided, and the holder can be detachably fixed to the storage portion by the screw engagement between the male screw and the female screw.

Since the opening end 50a of the holder 50 is engaged with the flange 44 of the oil bag by covering the oil bag 42, the holder 50 is screwed into the storage portion 46 so that the oil bag can be held. The flange is sandwiched between the open end of the holder and the storage part bottom wall 46a. That is, the oil bag 42 is fixed in the storage portion by sandwiching the flange 44 between the opening end 50a of the holder and the storage portion bottom wall 46a.

It is sufficient that the male screw 54 and the female screw 56 are at least partially formed at the corresponding positions.

In the hydraulic processing machine 10 having such a structure, oil is supplied from the oil filling port 58 to the reservoir 22 and the first chamber 26a.
, The second chamber 26b and the oil bag 42 are all filled and filled. Note that reference numeral 60
Is a bolt that functions as a plug for closing the oil filling port 58.

The portable hydraulic processing machine 10 having the above structure operates as follows.

As can be seen from FIG. 1, in the portable hydraulic processing machine 10 having the above-mentioned configuration, the return position (retracted position) where the first chamber 26a has the minimum volume is the initial position of the piston 28, Waits in this initial position when not activated. Further, in the initial position of the piston 28, the oil bag 42 is maintained in the original shape filled with oil.

When the switch means 18 is operated in such an initial state of the hydraulic processing machine 10, first, the pump mechanism 24 operates under the drive of the motor, whereby the oil in the reservoir 22 is pressurized oil. As the first chamber through the flow path 25
It is pumped and supplied to 26a. Then, the piston 28 moves forward in the starting direction (leftward in the figure) against the biasing force of the return spring 32, and the processing jig 30 that interlocks with the piston, for example, the pair of movable cutters 30-1 and the fixed cutter. Predetermined machining is performed by 30-2 (see FIG. 2).

Here, the maximum volume of the first chamber 26a is larger than the maximum volume of the second chamber 26b, and when the piston 28 moves forward, the amount of oil connecting the first chamber, the second chamber and the reservoir 22 is increased. Since the entire volume of the circulation path becomes large, in the hydraulic processing machine 10, the entire volume is made constant by contracting the oil bag 42. Then, the oil flowing out from the oil bag 42 is pressure-fed from the reservoir 22 to the first chamber 26a, thereby compensating for the shortage of oil in the oil circulation path.

As shown in FIG. 2, the oil bag 42 contracts under its own elasticity as the oil flows out, but the periphery of the oil bag is opened to the atmosphere through the ventilation hole 52 of the holder. Therefore, the contraction is smoothly performed.

When the piston 28 advances to a predetermined position, as shown in FIG. 2, the relief hole 40 is contacted by the contact of the valve rod 38 and the like with the opposite wall surfaces of the housing 12.
The head 38a moves away from the opening of the first chamber 26a,
The second chamber 26b communicates with each other, and the biasing force of the return spring 32 accumulated by the advance of the piston causes the pressurized oil in the first chamber to flow from the release hole to the second chamber, while returning the piston to the initial position. (See FIG. 1).

At this time, since the maximum volume of the first chamber 26a is larger than the maximum volume of the second chamber 26b, when the piston 28 tries to return to the initial position, excess oil is produced. However, this excess oil is returned to the inside of the oil bag under the restoring force of the oil bag 42 to the original shape, so that the sliding of the piston 28 makes it possible to make the entire volume of the oil circulation path constant. , This point is also compensated.

That is, the portable hydraulic processing machine 10 of the present invention
In the above, the contraction of the oil bag 42 and the restoration of the oil bag to the original shape are performed to stabilize the overall volume of the oil circulation path. The amount of oil in the circulation route is constantly adjusted. Therefore, the negative pressure caused by the sliding of the piston 28 is reliably prevented, and the smooth sliding of the piston can be easily ensured.

Then, in the hydraulic processing machine 10 of the present invention,
In the initial state of the piston 28, add oil from the oil filling port 58 to the reservoir 2
2. The first chamber 26a, the second chamber 26b, and the oil bag 42 need only be continuously filled, so that the final adjustment by additional oiling required in the known configuration is unnecessary. That is, since the final adjustment process can be omitted from the assembly process of the hydraulic processing machine 10, the work is simplified and the workability is improved.

Further, as described above, the oil bag 42
Is maintained in its original shape in the initial state of the piston 28, and is contracted only when the piston slides in the starting direction, that is, when the piston advances, so that the contracted state does not continue for a long time. Therefore, the reduction in the restoring force of the oil bag 42 can be surely suppressed, and the hydraulic processing machine 10 that does not impair the smooth flow of oil even during storage for a long period of time can be easily provided.

Here, in the embodiment of the present invention, the storage portion 46 is opened to the outside, and the oil bag 42 can be stored in the storage portion through the opening. But the storage
46 is an oil bag that can communicate with the atmosphere
It is sufficient if the inside of 42 is provided so as to communicate with the oil flow passage, and the present invention is not limited to this. Good.

However, as in this embodiment,
By providing the housing 12 with the storage portion 46 opened to the outside, the storage of the oil bag 42 from the outside, and
The oil bag can be removed from the opening to the outside. That is, by forming the storage portion 46 that is opened to the outside, the storage and replacement of the oil bag 42 can be performed without disassembling the hydraulic processing machine 10, so the workability during storage and replacement is reliably improved. To be done.

Although the housing 46 is formed in the housing 12 in the embodiment, the housing 46 is not limited to the housing because it can be communicated with both the outside and the oil circulation path individually. A housing portion may be provided in the casing 14, the motor housing 16, the support grip (not shown), and the like.

The storage section 46 includes a second chamber 26b,
Since it suffices to communicate with the oil flow path between the reservoirs 22, it is not limited to between the second chamber and the flow path 33 as shown in the drawing, and the storage portion is provided so as to be able to communicate with the flow path at other places. It may be provided. For example, the reservoir 22 may directly communicate with the inside of the oil bag 42.

Further, the structure is not limited to the holder 50, and the oil bag 42 may be fixed, for example, by screwing from the outside or by fitting a spring pin. However, with the holder 50 provided with the male screw 54 that can be screwed into the female screw 56 of the storage portion 46, the oil bag
In the configuration in which 42 is fixed in the storage portion, it is sufficient to screw the male screw and the female screw together, so that workability is improved.

Then, the opening end 50a of the holder advances in the direction of engagement with the flange 44 of the oil bag under the screwing that accompanies the insertion into the storage part 46, so that this opening end and the bottom wall of the storage part. It is possible to easily secure the close contact state of the flange with the bottom wall of the storage section by being sandwiched with 46a. Therefore, the communication between the atmosphere and the oil distribution path can be cut off without complicating the structure and work, and the oil leakage can be reliably prevented.

Furthermore, since the holder 50 covers the oil bag 42, the oil bag is reliably prevented from being exposed to the outside. Therefore, by isolating the oil bag 42 from the outside,
It is possible to prevent damage to the oil bag and ensure the safety of the oil bag.

In the embodiment of the present invention,
Although the oil bag 42 is embodied as a flanged shape, it goes without saying that the oil bag may have another shape when the oil bag is fixed to the storage portion by means other than the holder.

Further, since it is sufficient to cut off the communication between the atmosphere and the oil flow path by disposing the oil bag 42,
The opening end of the oil bag is not limited to being in close contact with the step portion formed by the storage section bottom wall 46a, and for example, the outer peripheral surface of the opening end of the oil bag may be in close contact with the storage section peripheral surface.

In this case, it is preferable that the step portion which can be engaged with the open end of the oil bag 42 is provided at least partially at the boundary portion between the storage portion 46 and the oil flow passage. In such a configuration, when the oil bag 42 is stored through the opening, the excessive advance of the oil bag is blocked by the engagement with the step portion, so that the step portion is stored in the oil bag 42. The positioning is performed when storing the, and the workability is improved by simplifying the work.

By the way, for example, as disclosed in Japanese Utility Model Publication No. 05-036568, an air bag is inserted from the outside,
In a known hydraulic processing machine having a replaceable structure, an air bag storage portion is usually formed in a substantially cylindrical shape and communicates with the second chamber and the like without a step or the like.
However, in this configuration, the continuous length of the housing tends to be long.

In the hydraulic type processing machine, normally,
In order to avoid an increase in the size of the housing, the wall thickness around the storage part etc. must be made as thin as possible. That is, if the continuous length of the hollow portion formed in the housing becomes long, the strength of the housing itself is unavoidably reduced.

However, as shown in FIG. 1, in the present invention, the accommodating portion 46 is formed in a substantially cylindrical shape having a bottom, and is communicated with the second chamber 26b through the communication hole 48 in the bottom wall of the accommodating portion. Therefore, the hollow portion of the housing is divided by the bottom wall 46a of the storage portion. In addition, since the hollow portion of the housing 12 is partially thickened in the bottom wall 46a of the housing portion, the strength of the housing itself is surely increased.

That is, as in the present invention, since the housing portion 46 has a substantially cylindrical shape with a bottom, the strength of the housing 12 is increased, so that it is possible to easily secure the reinforcement of the housing without increasing the size.

In the embodiment of the present invention,
A rebar cutter that uses a pair of movable cutters and a fixed cutter as a processing jig is embodied as a portable hydraulic processing machine, but is not limited to this. For example, a rebar bender, an electric puncher, or another portable tool. The present invention may be applied to a hydraulic processing machine.

The above-described embodiments of the present invention are for explaining the present invention and are not intended to limit the present invention in any way, and modifications and alterations may be made within the technical scope of the present invention. It goes without saying that all are included in this invention.

[0065]

As described above, according to the portable hydraulic processing machine of the present invention, oil is continuously supplied from the oil inlet to the reservoir, the first chamber, the second chamber and the oil bag in the initial state of the piston. It is enough to fill it. Therefore, there is no need for final adjustment of additional oil, etc.
Workability is improved.

Further, since the oil bag is maintained in its original shape in the initial state of the piston, it is possible to surely suppress the reduction of the restoring force of the oil bag, and to impair the smooth flow of oil even during storage for a long period of time. No hydraulic processing machine can be easily secured.

If the storage portion is formed in a shape that does not have a step portion on the opening end side that opens to the outside and interferes with the storage of the oil bag, the storage and replacement of the oil bag can be carried out by a portable hydraulic processing machine. Since it can be easily carried out through the opening without disassembling, the workability at the time of storage and replacement is surely improved.

Further, if the accommodating portion is formed into a substantially cylindrical shape and a communication hole is formed in the bottom of the accommodating portion so as to be able to communicate with the oil passage, the bottom wall serves as a step portion which can be brought into close contact with the end of the oil bag. Thus, the communication between the atmosphere and the oil distribution path is blocked, so that the oil leakage can be reliably prevented without complicating the configuration.

Since the hollow portion of the housing is divided by the bottom wall of the housing portion and the hollow portion of the housing is partially thickened on the bottom wall of the housing portion, the strength of the housing itself is surely increased. Therefore, by making the storage portion bottomed, it is possible to easily ensure the reinforcement of the housing without increasing the size.

Furthermore, if the oil bag is fixed in the storage portion by screwing the holder under the screwing between the corresponding male and female threads, the workability in fixing the oil bag is improved. Be improved. Then, if the holder can be fixed by screwing, the oil bag is fixed by sandwiching the flange between the opening end of the holder and the step portion such as the bottom wall of the storage portion. The close contact can be easily secured. Therefore, also in this respect, the leakage of oil can be reliably prevented without complicating the configuration and work.

[Brief description of drawings]

FIG. 1 is a schematic vertical cross-sectional view of a partial breakage in an initial state of a portable hydraulic processing machine according to the present invention embodied as a reinforcing bar cutter.

FIG. 2 is a partially cutaway schematic vertical cross-sectional view of the portable hydraulic processing machine in an operating state, corresponding to FIG.

[Explanation of symbols]

 10 Portable hydraulic processing machine (rebar cutter) 22 Reservoir 26 Cylinder 26a 1st chamber 26b 2nd chamber 28 Piston 30 Processing jig 42 Oil bag 44 Flange 46 Storage section 48 Communication hole 50 Holder 52 Vent hole 54 Male screw 56 Screw 58 Lubrication port

Claims (6)

[Claims] 1. A first chamber on the starting side and a second chamber on the returning side are defined in a cylinder in front of and behind a piston head, and a reservoir serving as an oil reservoir is provided through a corresponding flow path. Under the sliding of the piston, which is communicated with the second chamber and is pumped by the predetermined pump mechanism from the reservoir to the first chamber,
In a portable hydraulic processing machine that performs desired machining according to a processing jig that works with a piston, a hollow storage portion is formed in communication with the atmosphere, and a flexible oil bag is provided in a second chamber, A portable hydraulic processing machine, characterized in that it is arranged and fixed in an accommodating portion by communicating the inside with an oil flow path between reservoirs. 2. A first chamber on the starting side and a second chamber on the returning side are defined in the cylinder before and after the piston head, and a reservoir serving as an oil reservoir is provided through a corresponding flow path to the first, Under the sliding of the piston, which is communicated with the second chamber and is pumped by the predetermined pump mechanism from the reservoir to the first chamber,
In a portable hydraulic processing machine that performs desired machining according to a processing jig that works in conjunction with a piston, a hollow storage section is provided separately for the atmosphere and the oil flow path between the second chamber and the reservoir. A flexible oil bag, which is formed in communication with each other, is disposed and fixed in the storage portion by blocking the communication between the atmosphere and the oil flow path, and communicating the inside with the oil flow path. A portable hydraulic processing machine characterized by the following. 3. The storage portion is formed in a shape not having a step portion on the opening end side that interferes with the storage of the oil bag inside, and an engageable step portion at the opening end of the oil bag is provided. With storage
The portable hydraulic processing machine according to claim 1 or 2, wherein the hydraulic processing machine is formed at a boundary portion between the second chamber and the reservoir and an oil flow path. 4. A first chamber on the starting side and a second chamber on the returning side are defined in the cylinder in front of and behind the piston head, and a reservoir serving as an oil reservoir is provided through the corresponding flow passages. Under the sliding of the piston, which is communicated with the second chamber and is pumped by the predetermined pump mechanism from the reservoir to the first chamber,
In a portable hydraulic processing machine that performs the desired machining according to the processing jig that works with the piston, a substantially cylindrical hollow storage part with one end open to the outside is formed, and is installed on the bottom wall of the storage part. The storage part is communicated with the oil flow path between the second chamber and the reservoir via the communication hole, and the flexible oil bag having one end opened is connected to the storage part.
Under the close contact of the opening end with the bottom wall of the storage part, which becomes the step of the boundary part between the second chamber and the reservoir and the flow path of oil,
Portable hydraulic processing characterized in that the opening is aligned with the communication hole in the bottom wall of the storage part and is arranged and fixed in the storage part while blocking the communication between the atmosphere and the oil flow passage. Machine. 5. The portable hydraulic processing machine according to claim 4, wherein the storage portion is formed in a shape that does not have a step portion that hinders the storage of the oil bag inside, between the open end and the bottom wall. 6. A bottomed cylindrical holder, wherein an oil bag is formed with a flange on the side of the open end, and the open end of the holder is engageable with the flange of the oil bag by covering the oil bag. , The male screw and the vent hole at the bottom, and the female screw is provided in the storage part.The flange of the oil bag is attached to the open end of the holder under the screwing that accompanies the insertion of the holder into the storage part. The portable hydraulic processing machine according to any one of claims 3 to 5, wherein the portable hydraulic processing machine is sandwiched between the storage portion and a step portion between the oil flow passages.