JP2561789B2 - Forged product having a long hole, cylinder case having a fluid passage, forging method, and forging tool - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forged product having a long hole, a cylinder case having a fluid passage, a forging method,
And forging tools.

[0002]

2. Description of the Related Art Conventionally, processing (plastic processing) for forming a material into a desired shape by utilizing the plasticity of the material has been widely carried out in various fields. Since this type of processing can be performed without cutting, it has a feature that it is essentially a resource and energy saving type. It is also known that plastic working is suitable for mass production of products of the same size.

As one of the processing methods classified into plastic working, pressure is applied to a metal material using a tool such as a die to form the material into a predetermined shape while exerting a training effect on the material. There is forging.

As an example of a product molded by such a processing method, there is a bottomed cylindrical cylinder case which constitutes a fluid pressure cylinder, for example. here,
The structure of this type of fluid pressure cylinder 30 will be described based on an example shown in FIG.

As shown in FIG. 10, the cylinder case 31 has a bottom portion 32 and a side wall portion 33, and an elongated cylindrical recess 34 is formed inside thereof. A piston 36 having a rod 35 is slidably accommodated in the recess 34 of the cylinder case 31, and the interior of the recess 34 is partitioned by the piston 36 into a pair of cylinder chambers 37a and 37b.

A pair of fluid supply / discharge ports 38a, 38b are arranged close to each other on the bottom surface of the cylinder case 31. The first fluid supply / discharge port 38a and the first cylinder chamber 37a are communicated with each other via a linear fluid passage 39a penetrating the bottom portion 32. On the other hand, the second fluid supply / discharge port 38b and the second cylinder chamber 37b have the bottom portion 3
2 and the side wall portion 33 are communicated with each other through a fluid passage 39b formed by being bent.

When a cylinder case 31 having a bottomed cylindrical shape as shown in FIG. 10 is molded, pressure is usually applied in a state in which a metal material is placed between a pair of molds, so that the center portion of the metal material is first treated. The recess 34 is formed. Therefore, in the cylinder case 31 formed by forging, the fluid supply / discharge ports 38a, 38 are formed by a different processing method in a later step.
It is necessary to form b and the fluid passages 39a and 39b.

In this type of cylinder case 31, it is advisable to place both fluid supply / discharge ports 38a, 38b as close as possible in order to save space by concentrating the piping. .

[0009]

The fluid supply / drain ports 38a, 38b and the fluid passages 39a, 39b are generally formed by a drilling method or the like in the cylinder case 31 in which only the recess 34 is formed. In this case, the fluid supply / discharge ports 38a and 38b and the first fluid passage 39a, which have a simple shape, can be formed relatively easily by a single drilling process or the like.

However, since the second fluid passage 39a is long and bent, the machining is extremely difficult and complicated as compared with the other ones. For example, in order to form the fluid passage 39a in FIG. 10, first, four through holes or non-through holes which connect with each other are provided at four positions, and then the blocking member 40 is partially sealed. Required.

Moreover, in order to form the through hole in the side wall portion 33 of the cylinder case 31 by drilling or the like, it is necessary to secure at least a certain thickness of that portion. Therefore, this has been an obstacle to achieving the downsizing of the fluid pressure cylinder 30 in the related art.
Further, in the case of the configuration such as the fluid pressure cylinder 30, there is a problem that not only the number of locations to be machined increases but also it becomes difficult to secure high dimensional accuracy in each machined section.

Incidentally, FIG. 11 shows the fluid pressure cylinder 30.
Another hydraulic cylinder 41 is shown having a different configuration. In this conventional device 41, the cylinder case 42
A straight thin pipe 43 penetrating the bottom portion 32 and the piston 36 is used as an alternative to the long bent fluid passage shown in FIG. The advantage of such a through-pipe type is that there are no problems such as difficulty in drilling holes during manufacturing and enlargement of the fluid pressure cylinder 41.

However, when such a structure is adopted, another problem inevitably occurs in that the number of parts is increased and the structure is complicated. The present invention has been made in view of the above circumstances, and a first object thereof is a forging process having a long hole capable of eliminating the process of forming a long hole in a workpiece after the forging process. To provide things.

A second object of the present invention is to provide a forging method capable of easily forming a long hole having excellent dimensional accuracy in a difficult-to-machine portion easily and at low cost. Especially.

Further, a third object of the present invention is that although the fluid passage having excellent dimensional accuracy is provided in the side wall portion, it can be manufactured easily and at low cost, and the whole fluid pressure cylinder is large in size. It is an object of the present invention to provide a cylinder case having a fluid passage capable of avoiding deterioration.

A fourth object of the present invention is to provide a forging tool which can surely improve the dimensional accuracy of the long hole when forming the long hole in a workpiece by forging. To do.

[0017]

In order to solve the above-mentioned problems, in the invention described in claim 1, the space holder for forming the elongated hole can plastically deform and flow at least during the forging process. The gist is a forged product having a long hole obtained by forming a work piece inserted in a portion with a tool and then removing the space holder from the formed work piece.

In this case, the workpiece is made of a metal material for forming a bottomed cylindrical structure, and a portion into which the space holder is inserted is forged to form a side wall portion of the bottomed cylindrical structure. It may be a part that becomes.

According to the third aspect of the present invention, the space holder for forming the fluid passage is made of a metal material, which is inserted into at least a side wall portion of the cylinder case by forging using a tool. The gist of the invention is a cylinder case having a fluid passage in a side wall portion obtained by molding and then removing the space holder from the molded metal material.

Further, in the invention according to claim 4, the space holder for forming the elongated hole is inserted into at least a portion which can plastically deform and flow during the forging process by using a tool. The forging method is characterized in that the space holder is removed from the formed workpiece, and then the forging method is summarized.

Further, in the invention according to claim 6, there is provided a forging tool having a sliding hole in which a space holder for forming an elongated hole in a workpiece can move. It is a summary. In this case, the sliding hole may be provided in the accommodation space for accommodating the workpiece.

[0022]

When the workpiece is placed on the tool and a forming pressure is applied, the plastic workpiece is partially plastically deformed by the action of the forming pressure. At this time, a metal flow is generated particularly in the portion where the plastic deformation is great, and as a result, the workpiece, which is a lump or the like, is formed into a predetermined shape.

When the metal flow as described above occurs, the space holder itself does not undergo plastic deformation at all or hardly occurs. Therefore, a space around the space holder having a sectional shape substantially equal to that of the space holder is formed. Is retained. Therefore, when the above forging process is performed, a desired long hole is simultaneously formed. After that, the unnecessary space holder is removed from the formed workpiece. Therefore, in the forged product manufactured as described above, it becomes unnecessary to perform the long hole forming process on the object to be processed after the forging process.

Further, according to the forging method as described above, when the space holder is inserted into the workpiece, various conditions such as position, angle and depth are set in advance so that the predetermined length can be obtained. Holes will be formed. Therefore, it is possible to easily and inexpensively form a long hole having excellent dimensional accuracy even in a thin portion or the like which is generally considered to be difficult to process.

Further, in the case of the cylinder case having the fluid passage in the side wall portion of the present invention, when the metal material is placed on the tool and a molding pressure is applied thereto, the metal material is plastically deformed, particularly at the side wall portion of the cylinder case. Metal flow occurs in the.
As a result, a bottomed cylindrical cylinder case having a recess at the center is molded.

At this time, no plastic deformation occurs in the space holder itself inserted in the metal material, or almost no plastic deformation occurs in the space holder, so that a space having a cross-sectional shape substantially equal to that of the space holder is held around the space holder. . Therefore, when the above forging process is performed, a bent fluid passage extending from the side wall portion to the bottom portion of the cylinder case is simultaneously formed. After this,
The unnecessary space holder is removed from the fluid passage of the molded cylinder case.

Also in this case, when the space holder is inserted into the metal material, various conditions such as the position, angle and depth of the space holder are set in advance so that a predetermined fluid passage having excellent dimensional accuracy can be obtained. Will be formed. Therefore, there is no need to increase the wall thickness of the side wall for drilling or the like, and accordingly, the increase in size of the entire fluid pressure cylinder is avoided. In addition, the cylinder case is easier to manufacture than before because of the fact that complicated drilling is not required and the number of parts is reduced. Moreover, the fact that the drilling process is not necessary results in a reduction in the manufacturing cost of the cylinder case.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a method of manufacturing a fluid pressure cylinder having a fluid passage will be described in detail with reference to the drawings.

FIG. 1 shows a fluid pressure cylinder S manufactured by the method of this embodiment. A cylinder case 1 constituting this fluid pressure cylinder S includes a bottom portion 2 and a side wall portion 3 each having a quadrangular cross section, and a concave portion 4 having an elongated cylindrical cross section is formed inside thereof. Cylinder case 1
An end cover 5 is fitted to the open end of the. An internal space 6 is defined by the end cover 5 and the recess 4 of the cylinder case 1.

A piston 8 having two rods 7 is housed in the internal space 6 slidably in the longitudinal direction of the cylinder case 1. A part of both rods 7 penetrates the rod insertion hole 9 of the end cover 5 and projects to the outside of the cylinder case 1. A mounting plate 10 for fixing a driven member (not shown) is fixed to the tips of the rods 7.

The internal space 6 is divided by a piston 8 into a first cylinder chamber 11a and a second cylinder chamber 11b. Further, on the bottom surface of the cylinder case 1, a pair of fluid supply / discharge ports 12a, 12b are arranged close to each other for the purpose of concentrating the pipes on one side to save space.

The first fluid supply / discharge port 12a and the first cylinder chamber 11a are communicated with each other via a linear fluid passage 13a that penetrates substantially the center of the bottom portion 2. on the other hand,
Second fluid supply / discharge port 12b and second cylinder chamber 11
b is communicated with the fluid passage 13b formed by bending from the bottom portion 2 to the side wall portion 3.

Now, a method of manufacturing the bottomed cylindrical cylinder case 1 used in the fluid pressure cylinder S of this embodiment by forging will be described in detail with reference to FIGS. As the workpiece to be the cylinder case 1, as shown in FIG. 2, a square metal material 14 such as aluminum having plasticity is selected. The metal material 14 includes
The accommodation hole 14a that penetrates the upper end surface and the lower end surface is previously formed by drilling or the like. The accommodation hole 1
The portion where 4a is formed is a portion near the outer edge of the metal material 14.

A wire 17 as a space holder is inserted into the accommodation hole 14a. As a tool for performing forging, a die 1 is used as shown in FIG.
A pair of molds composed of 5 and punch 16 is used. Inside the die 15, an accommodation space 15a having a rectangular cross section for accommodating the metal material 14 is formed. Further, the shape of the punch 16 is a long cylindrical cross section,
The size of its outer shape is slightly smaller than that of the accommodation space 15a. Therefore, when the punch 16 is arranged, a space 18 is formed between the punch 16 and the inner wall of the accommodation space 15a.

The width of the void 18 is set to be at least slightly larger than the diameter of the wire 17. Then, on the inner bottom surface of the die 15, the metal material 14
Is formed with a sliding hole 15b for inserting the wire rod 17 projecting from the lower end surface thereof.

When performing the forging process, as shown in FIG. 3, the metal material 14 is first accommodated in the accommodation space 15a, and the punch 16 is disposed above it. At this time, the punch 16 is positioned so that the center line of the punch 16 and the center line of the accommodation space 15a coincide with each other. Next, by moving the punch 16 in the direction of arrow A1 in FIG. 4, a predetermined forming pressure is applied to the upper end surface of the metal material 14.

Then, the plastic metal material 14 is partially plastically deformed by the molding pressure. In this case, the plastic deformation is particularly great at the outer peripheral portion of the upper end surface of the metal material 14, and the metal in that portion flows in the direction of arrow A2 in FIG. 4 along the space 18 between the punch 16 and the accommodation space 15a. As a result, the concave portion 4, the bottom portion 2 and the side wall portion 3 having a predetermined shape are formed inside the metal material 14.

When the metal flow as described above occurs, the accommodation hole 14a previously provided in the metal material 14 is provided.
The wire rod 17 ensures the cross-sectional shape of the wire rod 17 and is stretched in the same direction.

However, even when metal flow occurs, the wire 1
Since no noticeable plastic deformation occurs in 7 itself, a space approximately equal to the cross-sectional shape of the wire 17 is retained inside the extended accommodation hole 14a. Moreover, the wire rod 17
Also in the region above the upper end of, the space substantially equal to the cross-sectional shape of the wire 17 is maintained. That is, when the above-described forging process is performed, not only the concave portion 4, the bottom portion 2 and the side wall portion 3 are formed, but also the long and curved fluid passage 13b is formed at the same time.

After that, the molded metal material 14 is taken out from the die 15, and the wire 17 is changed to the arrow A in FIG.
It is pulled out in the direction of 3. The metal material 14 is provided with fluid supply / discharge ports 12a, 12 by drilling or the like.
b and the fluid passages 13a and 13b are formed. Further, by drilling the upper end portion of the fluid passage 13b, a through hole 13c connected to the fluid passage 13b is formed, and the closing member 3a is embedded in a predetermined portion. Similarly,
By drilling a lower end portion of the fluid passage 13b, a non-through hole 13d connected to the fluid passage 13b is formed, and the closing member 3a is embedded in a predetermined portion.

According to the forging process of this embodiment, when the wire rod 17 is inserted into the metal material 14, if the conditions such as the position, angle and depth are set in advance, it will be compared with the drilling process. The fluid passage 13b having excellent dimensional accuracy can be formed. Therefore, unlike the case of the conventional cylinder case, it is not necessary to increase the wall thickness of the side wall portion 3 for drilling or the like. As a result, the increase in size of the entire fluid pressure cylinder S can be reliably avoided.

Further, according to the present embodiment, the manufacture of the cylinder case 1 becomes extremely easy as compared with the conventional case because the complicated drilling is not required and the number of parts is reduced. Moreover, in the manufacturing process, the need for drilling such as forming a long hole is eliminated, which leads to a reduction in the manufacturing cost of the cylinder case 1.

Further, in this embodiment, the wire rod 17 having a circular cross section and a uniform cross section is used as the space holder when forming the fluid passage 13b. For this reason, it becomes extremely easy to remove the unnecessary space holder after the forging process. In particular, the use of the pull-out stopper 17a provided at one end of the wire 17 makes the pull-out work even easier.

The present invention is not limited to the above embodiment, but can be modified as follows. For example, (1) a fluid pressure cylinder S as another example 1 shown in FIG.
It may be a.

In the cylinder case 23 constituting the fluid pressure cylinder Sa, the second fluid passage 13b formed by forging has a substantially curved continuous shape from the bottom portion 2 to the upper end of the side wall portion 3. It is characteristic.
Therefore, the movement resistance of the fluid moving in the second fluid passage 13b is physically smaller than that of the fluid passage having a configuration in which a plurality of through holes and non-through holes are connected.

Therefore, the cylinder case 23 has an advantage that fluid can be smoothly supplied and discharged as compared with the conventional cylinder case. This means that the fluid pressure cylinder S
This is extremely convenient for speeding up the operation of a.
Considering this advantage from another perspective, the following can be said.

That is, even when the diameter of the second fluid passage 13b is set to be smaller than that of the conventional fluid passage, it is possible to secure the same fluid supply / exhaust capacity as that of the conventional fluid passage. As a result of allowing the second fluid passage 13b to have a smaller diameter, it is possible to reduce the size of the entire fluid pressure cylinder Sa without lowering the fluid supply / exhaust capability.

Further, the number of parts can be further reduced by adopting the structure as in the other example 1. (2) The present invention is not limited to only the cylinder cases 1 and 23 having the shapes shown in the above-mentioned embodiment and the other example 1. For example, it may be a bottomed tubular structure 20 like another example 2 shown in FIG. 7. The bottomed tubular structure 20 of the second example shown in FIG. 7 is provided with a recess 20a having a substantially square cross section, which has the same outer shape. The bottomed tubular structure 2 is provided on the side wall portion 20c of the bottomed tubular structure 20.
An elongated hole 20b extending along the longitudinal direction of 0 is formed. Further, it is of course possible to adopt a shape such as a cylindrical shape as the outer shape of the cylinder cases 1 and 23.

(3) Of course, one cylinder case may be provided with a plurality of recesses and a plurality of slots. For example, the bottomed tubular structure 21 of the third example shown in FIG. 8 has two recesses 21a having a circular cross section. Then, the side wall portion 21 of the bottomed tubular structure 21
Three elongated holes 21b are formed in c.

Further, if such a structure is further developed, for example, a bottomed cylindrical cooling or heating container having a large number of fluid passages for circulating a heat exchange medium in its side wall portion, etc. It becomes possible to manufacture.

(4) Furthermore, the present invention is not limited to the bottomed cylindrical structure such as the embodiment and the other examples 1, 2 and 3, and for example, another example shown in FIG. 4 may be a structure 22 in which a part of the side wall of the bottomed cylindrical structure is cut out. A long hole 22b is formed in the side wall portion 22a of the structure 22 similarly to the long holes 20b and 21b. Further, it is of course possible to apply a shape other than the structure 22 to, for example, a structure having no bottom.

(5) The elongated holes formed in the workpiece are not limited to the through holes, but may be the non-through holes. When forming such a non-through hole, forging may be performed in a state where the space holder is not completely inserted into the accommodation hole. Due to the molding pressure at this time, a long hole is formed in the portion where the space holder is present, while the portion where the space holder is not present is filled.

As a method other than that, it is of course possible to perform the forging process with the accommodation hole provided in the workpiece in advance being a non-through hole and inserting the space holder in the non-through hole. .

(6) The accommodation hole, which becomes a long hole after the forging process, does not necessarily have to be provided in advance in the workpiece. For example, a method of forming the accommodation hole at the same time as inserting the space holder by press-fitting the space holder into the workpiece may be used.

(7) Unlike the cylinder case 1 of the embodiment and the modified example 1, for example, the second fluid supply / discharge port 12b and the second cylinder chamber 11b are connected via a plurality of fluid passages 13b. Is also good. With this configuration, the diameter of each fluid passage 13b can be further reduced, so that the cylinder case 1 can be further downsized. Even in such a case, the plurality of fluid passages 13
There is an advantage that b is simultaneously formed during the forging process.

(8) The material to be processed is not limited to a metal material such as aluminum, iron and copper, but may be a resin material having plasticity. (9) The forging tool is not limited to the die 15 and the punch 16 as in the embodiment, but other die forging tools can be used. Further, multi-ram forging in which a plurality of punches are driven from different directions with respect to one die may be used. Further, it is not limited to the die forging as described above, and may be applied to, for example, free forging or rotary forging.

(10) The space retainer is not limited to the wire rod 17 shown in the embodiment. Further, the cross-sectional shape does not necessarily have to be uniform and circular, and may be another shape such as a plate shape.

(11) Further, the space holder and the space in the workpiece in which the space holder is housed need not necessarily match. (12) Wire rod 17 used as a space holder in the examples
Instead of this, it is possible to use a solder which can be melted and removed by a heat treatment or the like, such as an elongated solder.

(13) Stopper 17 formed on wire 17
The shape of a may be arbitrary. Further, the formation of the stopper 17a is not essential, and the wire rod 1 can be formed without it.
No inconvenience will occur when the 7 is removed.

[0060]

As described above in detail, according to the forged product having a long hole of the present invention, it is possible to eliminate the need for forming a long hole in a work after the forging process. Produce an effect.

Further, according to the forging method of the present invention, it is possible to easily form a long hole having excellent dimensional accuracy and at low cost even in a portion which is generally difficult to process. Play.

Further, according to the cylinder case having the fluid passage of the present invention, it is possible to easily and inexpensively manufacture the fluid pressure cylinder despite having the fluid passage having the excellent dimensional accuracy in the side wall portion. It has an excellent effect that it is possible to avoid an increase in size of the entire device.

According to the forging tool of the present invention, when forming a long hole in a workpiece by forging, the dimensional accuracy of the long hole can be surely improved.

[Brief description of drawings]

FIG. 1 is a front sectional view showing a fluid pressure cylinder of an embodiment.

FIG. 2 is a perspective view showing a state in which a wire is inserted into a metal material housing hole for molding a cylinder case.

FIG. 3 is a partial front cross-sectional view showing a state in which a metal material is housed in a housing recess of a die.

FIG. 4 is a partial front cross-sectional view showing a state of plastic deformation of a metal material that occurs during forging.

FIG. 5 is a front cross-sectional view showing a state when a wire rod is pulled out from a molded metal material.

FIG. 6 is a front sectional view showing a fluid pressure cylinder of Modification 1.

FIG. 7 is a schematic perspective view showing a bottomed cylindrical structure of another example 2 obtained by forging.

FIG. 8 is a schematic perspective view showing a bottomed cylindrical structure of another example 3 obtained by forging.

FIG. 9 is a schematic perspective view showing a structure of another example 4 obtained by forging.

FIG. 10 is a front sectional view showing a cylinder case that constitutes a conventional fluid pressure cylinder.

FIG. 11 is a front cross-sectional view showing a cylinder case (through pipe type) that constitutes a conventional fluid pressure cylinder.

[Explanation of symbols]

1, 23 ... Cylinder case as a bottomed cylindrical structure,
3, 20c, 21c, 22a ... Side wall portion, 20, 21, 2
2 ... bottomed cylindrical structure, 20b, 21b, 22b ... long hole,
13b ... (second) fluid passage as long hole, 14 ... metal material as work piece, 15 ... die as tool, 1
5a ... accommodating space, 15b ... accommodating hole, 16 ... punch as tool, 17 ... wire material as space holder, S, Sa ... fluid pressure cylinder.

Continuation of front page (56) Reference JP 57-58945 (JP, A) JP 57-148043 (JP, A) JP 58-151935 (JP, A) JP 4-28446 (JP , A) Japanese Patent Publication No. 46-24536 (JP, B1)

Claims (7)

(57) [Claims] 1. Long holes (13b, 20b, 21b, 22b)
A space holding body (17) for forming a groove is formed by using a tool (15, 16) to form a workpiece (14) inserted at least in a portion which can be plastically deformed and flow during forging. A forged product having an elongated hole obtained by removing the space holder (17) from the formed work (14). 2. The workpiece (14) is a metal material for forming a bottomed tubular structure (1, 20, 21),
A portion into which the space holder (17) is inserted is a portion which becomes a side wall portion (3, 20c, 21c) of the bottomed tubular structure (1, 20, 21) by forging. A forged product having a long hole according to claim 1. 3. A metal material in which a space holder (17) for forming a fluid passage (13b) is inserted into at least a portion to be a side wall portion (3) of a cylinder case (1, 23) by forging. A cylinder case having a fluid passage obtained by molding (14) with a tool (15, 16) and then removing the space holder (17) from the molded metal material (14). 4. Long holes (13b, 20b, 21b, 22b)
A space holder (17) for forming a groove is formed by using a tool (15, 16) to form a workpiece (14) inserted into at least a portion that can be plastically deformed and flowed during forging. A forging method, characterized in that the space holder (17) is removed from the formed workpiece (14). 5. The forging method according to claim 4, wherein the space holder (17) is a wire rod. 6. A long hole (13b, 20) in a workpiece (14).
b, 21b, 22b) to form a space holder (1
7) A sliding hole (15) capable of moving inside thereof.
Forging tool with b). 7. The forging tool according to claim 6, wherein the sliding hole (15b) is provided in an accommodation space (15a) for accommodating the workpiece (14).