Patent Application
20160175909
The present invention relates to a pipe bend die unit that is appropriate for bending a pipe, and a pipe bending apparatus having the unit.
As for working to bend a pipe, various kinds of working such as press bending, compression bending, extract bending, draw bending and the like are known heretofore, among which a rotary draw bending is most popular. According to an ordinary rotary draw bending, a pipe is held by a clamp die against a bend die with a groove formed on its outer peripheral surface, and the bend die and clamp die are rotated, with the pipe being pressed toward the bend die by means of a pressure die, then the pipe is moved in a tangential direction, thereby to be bent along the groove of the bend die, as disclosed in the first and second columns of Patent document 1, for example, and also disclosed in Patent document 2, in its paragraphs (0003)-(0006) and FIG. 11, wherein the bend die is described as a roll die.
In Patent document 2, with respect to a wiper or shoe provided for preventing a crinkling from being created on the inner side of a bent portion of the pipe, a specific wiper is proposed to do with wear or breakage caused by a sliding motion, as described in its paragraphs (0013) and (0014). Likewise, in Patent document 3, it is described in its paragraph (0005) as an object to provide a pipe bending apparatus having a wear resistance, being used for various kinds of pipes without causing a problem, and having a very long life without requiring adjusting operations very often, and such a pipe bending apparatus is proposed in its paragraph (0006) that is characterized in that the pipe bending apparatus has a bend die with its outer peripheral surface formed in a circular arc of a predetermined curvature to bend a pipe, a clamp member clamping the pipe with the bend die, and a wiper rotating the clamp member about the bend die to prevent a crinkling from being created when the pipe is bent, and that a tip end portion of the wiper in the rotating direction of the clamp member is extended along the curvature of the outer peripheral surface of the bend die beyond an initial point for bending the pipe.
Furthermore, in Patent document 4, with respect to a method and apparatus for quickly and accurately changing die sets for different-sized tubing to be bent or for different types of tube bending operations, it is described in its page 7 that a preassembled die set has been devised for tube bending apparatus wherein the die set is comprised of a bend die, clamp die and pressure die adapted to be mounted on a spindle of a tube bending table, the improvement comprising first means releasably interconnecting the pressure die and clamp die to the bend die in predetermined, aligned relation to one another and to the bend die, and handling means for engaging the die set in order to simultaneously lift and remove said dies comprising each die set from the table. And, it is described in its page 8 that many tube bending operations require the use of a wiper die and mandrel, which may also provide a part of each preassembled die set when needed, and such an embodiment that the wiper die is joined to the bend die by a wiper die arm is disclosed in its page 15 and FIG. 6.
Patent document 1: U.S. Pat. No. 5,337,590
Patent document 2:
Patent document 3:
Patent document 4:
Japanese Patent Laid-open Publication No. Hei-11-512029
Although it is configured to form the crinkling intentionally in Patent document 1, in order to prevent the crinkling being created when the draw rotary bending is performed, a crinkling prevention is employed in general, so that the wiper is disposed in Patent documents 2, 3 and 4. Among them, each wiper as described in Patent documents 2 and 4 has a tip end portion formed into a wedge shape, and possible wear of the tip edge portion was concerned in Patent document 2, so that a counter measure has been considered. Particularly, there is a step along the initial line for bending the pipe, normally a line where a surface including a rotary axis of the bend die intersects an inner surface of a groove of the bend die, a crinkling resulted from the step cannot be avoided. In order to minimize this crinkling, it is necessary to maintain the wedge shape of the tip end portion of the wiper, especially necessary to make the tip end portion as thinner as possible, so that the wiper is fragile and lacks its durability. Furthermore, a periodic wear countermeasure is unavoidable, and frequent replacements are required. In addition, as an initial setting for the bending is difficult, skilled technique is required. Therefore, it is difficult to perform a large amount of bending operations continuously.
In contrast, according to Patent document 3, a wiper disclosed as one embodiment therein configures a part of a central die section out of bending die sections which were divided into three sections along a vertical direction, and it is formed with a recess portion of a circular arc cross section, as described in its Paragraphs (0025)-(0030). Consequently, it is described in its Paragraph (0032) that a tip end portion with an edge structure is not required, and that there will be no possibility for creating a step between the bend die and the wiper, the reason of which has not been explained. Supposing that, from a start to an end of bending operation applied to a pipe to be formed, out of the bending die sections divided into three sections along three planar surfaces parallel to a pipe axis, upper and lower side die sections perform the bending, and the central section performs as the wiper, thereby to perform separate operations, not only it is difficult to prevent the crinkling from being created, but also it is difficult to perform the bending operation appropriately. No disclosure can be found about a configuration for enabling a desired bending operation.
In the meantime, although it is described in Patent document 4 that the die set with the bend die, clamp die and pressure die being preassembled can be changed to perform bending operations in different forms, as described in its Page 11, a wiper die is not necessarily required. In other words, Patent document 4 focuses on a performance of changing dies, but never discloses such a die set that can change dies with the performance of appropriately preventing the crinkling from being created, nor discloses a pipe bend die unit that is appropriate for bending a pipe and a pipe bending apparatus having the pipe bend die unit.
Accordingly, it is an object of the present invention to provide a pipe bend die unit that can perform bending a pipe appropriately without creating a crinkling. And, it is another object of the present invention to provide a pipe bending apparatus having the pipe bend die unit which is appropriate for the bending.
It is a further object of the present invention to provide a pipe bend die unit that can perform bending a pipe appropriately without creating a crinkling, and perform changing dies easily, and to provide a pipe bending apparatus having the unit.
To solve the above-described problems, the present invention comprises a bend die with a pipe-receiving groove of half-circular cross section formed on an outer peripheral surface of the bend die, the bend die being rotatable about a rotary axis, and the bend die comprises a clamp member having a first groove part of half-circular cross section on an outer peripheral surface of the clamp member with a fitting recess formed on the first groove part and extending in a peripheral direction by a first predetermined length on a planar surface perpendicular to the rotary axis, and a counter pressure member having a second groove part of half-circular cross section formed on an outer peripheral surface of the counter pressure member, and a fitting protrusion extending in a peripheral direction by a second predetermined length from a tip end portion of the second groove part, the fitting protrusion being positioned in the fitting recess so that the first and second groove parts combine to form the pipe-receiving groove of half-circular cross section, the counter pressure member and the clamp member being hingedly connected to one another so as to be rotatable relative to each other about the rotary axis.
In the pipe bend die unit as described above, it may be so configured that one part of the fitting protrusion is located at a foreside in an advancing direction of the pipe relative to a position where a bending operation of the pipe is initiated, and that an other part of the fitting protrusion is located at a backside in the advancing direction of the pipe relative to the position where the bending operation of the pipe is initiated. Or, it may be so configured that a fitting portion of the fitting protrusion that is positioned in the fitting recess is located at a foreside in an advancing direction of the pipe relative to a position where a bending operation of the pipe is initiated, and that a mating portion at which the first groove part of the clamp member and the second groove part of the counter pressure member mate is located at a backside in the advancing direction of the pipe relative to the position where the bending operation of the pipe is initiated.
It may be so configured that the counter pressure member has an annular rotary support portion mounted to be rotatable about the rotary axis, and that a part of the rotary support portion forms the fitting protrusion, and that the rotary support portion possesses an outer peripheral surface, the outer peripheral surface of the rotary support portion being a curved surface forming a part of the pipe-receiving groove of half-circular cross section. Furthermore, it may be so configured that the counter pressure member and the clamp member are hingedly connected by an axial member having a central axis passing through the fitting recess.
Also, in the pipe bend die unit as described above, it may be so configured that the clamp member has a circularly recessed portion forming the first groove part of half-circular cross section, the fitting recess extending in a peripheral direction on a planar surface perpendicular to the rotary axis, the fitting recess being located at a bottom center of the circularly recessed portion, the first groove part of half-circular cross section being continuous with the circularly recessed portion including a part of the fitting recess, and that the counter pressure member includes a curved surface portion formed on opposite sides of the planar surface, the curved surface portion being configured to contact the circularly recessed portion, the curved surface portion possessing an arch center on an axis offset from the rotary axis and perpendicular to the planar surface in a direction spaced from the rotary axis, the second groove part on the outer peripheral surface of the fitting protrusion possessing the half-circular cross section, with a bottom center of the second groove part being provided on the planar surface perpendicular to the rotary axis, next to the curved surface portion.
Furthermore, it may be so configured that one part of the fitting protrusion is located at a foreside in an advancing direction of the pipe relative to a position where a bending operation of the pipe is initiated, and that an other part of the fitting protrusion is located at a backside in the advancing direction of the pipe relative to the position where the bending operation of the pipe is initiated.
Or, it may be so configured that the counter pressure member has an annular rotary support portion mounted to be rotatable about the rotary axis, and a body portion formed integrally with the rotary support portion, the second groove part of half-circular cross section and the curved surface portion being provided on the body portion of the counter pressure member, a part of the rotary support portion being formed integrally with the body portion and extending outwardly in a radial direction of the rotary support portion, and that the rotary support portion forms the fitting protrusion, and the rotary support portion possesses an outer peripheral surface, the outer peripheral surface of the rotary support portion being a curved surface forming a part of the pipe-receiving groove of half-circular cross section. Particularly, it may be so configured that the second groove part of half-circular cross section of the body portion of the counter pressure member forms an obtuse angle with a side surface of an end portion of the second groove part formed next to the curved surface portion. It may be so configured that the counter pressure member comprises at least a first member and a second member, the rotary support portion constituting a main part of the first member, and the body portion constituting a main part of the second member, the counter pressure member being formed by combining the first member and the second member.
Also, in the pipe bend die unit as described above, the bend die may be configured by an upper section and a lower section divided by a surface perpendicular to the rotary axis, the fitting protrusion of the counter pressure member being disposed between the upper section and the lower section.
Also, in the pipe bend die unit as described above, it may be so configured that the counter pressure member is divided into at least two members, the at least two members being a mating member including the fitting protrusion and a rotary support member supported to be rotatable about the rotary axis, the mating member being detachably connected to the rotary support member. It may be so configured that the clamp member and the counter pressure member comprise a plurality of members divided by a plurality planes perpendicular to the rotary axis, and that the plurality of members are stacked to form the clamp member and the counter pressure member. Furthermore, it may further comprise a knock pin fixed to a predetermined position of the clamp member, to provide an initial relative position between the clamp member and the counter pressure member by a position where the counter pressure member abuts on the knock pin.
Also, the present invention is to provide a pipe bending apparatus that comprises a bend die having a pipe-receiving groove of half-circular cross section on an outer peripheral surface of the bend die, the bend die being rotatable about a rotary axis, a clamp die for clamping a pipe to be bent that is positioned in the pipe-receiving groove of the bend die, and a pressure die for pressing the pipe toward the bend die, and that the bend die comprises a clamp member having a first groove part of half-circular cross section on an outer peripheral surface of the clamp member with a fitting recess formed on the first groove part and extending in a peripheral direction by a first predetermined length on a planar surface perpendicular to the rotary axis, and a counter pressure member having a second groove part of half-circular cross section formed on an outer peripheral surface of the counter pressure member, and a fitting protrusion extending in a peripheral direction by a second predetermined length from a tip end portion of the second groove part, the fitting protrusion being positioned in the fitting recess so that the first and second groove parts combine to form the pipe-receiving groove of half-circular cross section, the counter pressure member and the clamp member being hingedly connected to one another so as to be rotatable relative to each other about the rotary axis, to configure a pipe bend die unit.
Also, in the pipe bending apparatus as described above, it may be so configured that one part of the fitting protrusion is located at a foreside in an advancing direction of the pipe relative to a position where a bending operation of the pipe is initiated, and that an other part of the fitting protrusion is located at a backside in the advancing direction of the pipe relative to the position where the bending operation of the pipe is initiated.
Furthermore, it may be so configured that the clamp member has a circularly recessed portion forming the first groove part of half-circular cross section, the fitting recess extending in a peripheral direction on a planar surface perpendicular to the rotary axis, the fitting recess being located at a bottom center of the circularly recessed portion, the first groove part of half-circular cross section being continuous with the circularly recessed portion including a part of the fitting recess, and that the counter pressure member includes a curved surface portion formed on opposite sides of the planar surface, the curved surface portion being configured to contact the circularly recessed portion, the curved surface portion possessing an arch center on an axis offset from the rotary axis and perpendicular to the planar surface in a direction spaced from the rotary axis, the second groove part on the outer peripheral surface of the fitting protrusion possessing the half-circular cross section, with a bottom center of the second groove part being provided on the planar surface perpendicular to the rotary axis, next to the curved surface portion.
Furthermore, it may be so configured that the counter pressure member has an annular rotary support portion mounted to be rotatable about the rotary axis, and a body portion formed integrally with the rotary support portion, the second groove part of half-circular cross section and the curved surface portion being provided on the body portion, a part of the rotary support portion being formed integrally with the body portion and extending outwardly in a radial direction of the rotary support portion, and that the rotary support portion forms the fitting protrusion, and the rotary support portion possesses an outer peripheral surface, the outer peripheral surface of the rotary support portion being a curved surface forming a part of the pipe-receiving groove of half-circular cross section. Also, the counter pressure member may comprise at least a first member and a second member, the rotary support portion constituting a main part of the first member, and the body portion constituting a main part of the second member, the counter pressure member being formed by combining the first member and the second member.
In the pipe bending apparatus as described above, it may be so configured that the counter pressure member and the clamp member are hingedly connected by an axial member having a central axis passing through the fitting recess. Also, the bend die may be configured by an upper section and a lower section divided by a surface perpendicular to the rotary axis, the fitting protrusion of the counter pressure member being disposed between the upper section and the lower section.
Also, in the pipe bending apparatus as described above, it may further comprise a knock pin fixed to a predetermined position of the clamp member, to provide an initial relative position between the clamp member and the counter pressure member by a position where the counter pressure member abuts on the knock pin. Furthermore, the apparatus may comprise a mandrel with a tip end portion thereof being inserted into the pipe, the mandrel being driven such that the tip end portion opposes the pressure die within a predetermined rotating region of the bend die.
As the present invention is configured as described above, the following effects can be achieved. That is, according to the pipe bend die unit of the present invention, the bend die configuring it comprises a clamp member having a first groove part of half-circular cross section on an outer peripheral surface of the clamp member with a fitting recess formed on the first groove part and extending in a peripheral direction by a first predetermined length on a planar surface perpendicular to the rotary axis, and a counter pressure member having a second groove part of half-circular cross section formed on an outer peripheral surface of the counter pressure member, and a fitting protrusion extending in a peripheral direction by a second predetermined length from a tip end portion of the second groove part, the fitting protrusion being positioned in the fitting recess so that the first and second groove parts combine to form the pipe-receiving groove of half-circular cross section, and the counter pressure member and the clamp member are hingedly connected to one another so as to be rotatable relative to each other about the rotary axis. Therefore, the bending of the pipe can be achieved appropriately without causing the crinkling. Furthermore, if a plurality of pipe bend die units are prepared in accordance with various shapes of pipes to be bent, when a pipe is to be bent in a shape, a pipe bend die unit for the shape to be bent may be simply selected and changed, so that such a pipe bend die unit can be provided that its die change can be performed easily, and that no adjustment is required after the die change.
In the pipe bend die unit as described above, if such a configuration is employed that one part of the fitting protrusion is located at a foreside in an advancing direction of the pipe relative to a position where a bending operation of the pipe is initiated, and an other part of the fitting protrusion is located at a backside in the advancing direction of the pipe relative to the position where the bending operation of the pipe is initiated, or if such a configuration is employed that a fitting portion of the fitting protrusion positioned in the fitting recess is located at a foreside in an advancing direction of the pipe relative to a position where a bending operation of the pipe is initiated, and a mating portion at which the first groove part of the clamp member and the second groove part of the counter pressure member is located at a backside of the advancing direction of the pipe relative to the position where the bending operation of the pipe is initiated, smooth bending of the pipe can be achieved without causing the crinkling.
If the counter pressure member is formed to have an annular rotary support portion mounted to be rotatable about the rotary axis, it can be surely supported to be rotatable about the rotary axis. Particularly, it can be hingedly connected with the clamp member easily, and if it is so configured that a part of the rotary support portion forming the fitting protrusion, and that the rotary support portion possesses an outer peripheral surface, with the outer peripheral surface of the rotary support portion being a curved surface forming a part of the pipe-receiving groove of half-circular cross section, the counter pressure member can be formed as a single part with an appropriate shape. Also, if it is so configured that the counter pressure member and the clamp member are hingedly connected by an axial member having a central axis passing through the fitting recess, smooth bending of the pipe can be achieved without causing the crinkling.
In the pipe bend die unit as described above, if such a configuration is employed that the clamp member has a circularly recessed portion forming the first groove part of half-circular cross section, the fitting recess extending in a peripheral direction on a planar surface perpendicular to the rotary axis, the fitting recess being located at a bottom center of the circularly recessed portion, the first groove part of half-circular cross section being continuous with the circularly recessed portion including a part of the fitting recess, and that the counter pressure member includes a curved surface portion formed on opposite sides of the planar surface, the curved surface portion being configured to contact the circularly recessed portion, the curved surface portion possessing an arch center on an axis offset from the rotary axis and perpendicular to the planar surface in a direction spaced from the rotary axis, the second groove part on the outer peripheral surface of the fitting protrusion possessing the half-circular cross section, with a bottom center of the second groove part being provided on the planar surface perpendicular to the rotary axis, next to the curved surface portion, then, the tip end portion of the curved surface portion of the counter pressure member at the initial position for bending the pipe tightly contacts the circularly recessed portion of the clamp member, whereas a clearance is formed between the curved surface portion of the counter pressure member and the circularly recessed portion at other portions than the tip end portion, even if the relative rotational angle between the clamp member and the counter pressure member is changed. Therefore, the counter pressure member can be assembled with the clamp member easily and appropriately, without causing an interference with the circularly recessed portion, and a durability of the counter pressure member will be improved.
In the pipe bend die unit as described above, if it is so configured that one part of the fitting protrusion is located at a foreside in an advancing direction of the pipe relative to a position where a bending operation of the pipe is initiated, and an other part of the fitting protrusion is located at a backside in the advancing direction of the pipe relative to the position where the bending operation of the pipe is initiated, smooth bending of the pipe can be achieved without causing the crinkling.
If the counter pressure member is formed to have an annular rotary support portion mounted to be rotatable about the rotary axis, and a body portion formed integrally with the rotary support portion, the second groove part of half-circular cross section and the curved surface portion being provided on the body portion, a part of the rotary support portion being formed integrally with the body portion and extending outwardly in a radial direction of the rotary support portion, the counter pressure member can be surely supported to be rotatable about the rotary axis, and can be hingedly connected with the clamp member easily.
In addition, as a part of the rotary support portion is formed to extend outwardly in a radial direction of the rotary support portion, stress concentration applied to the rotary support portion can be relieved, so that durability of the counter pressure member will be improved. As the rotary support portion is configured to form the fitting protrusion, and the outer peripheral surface of the rotary support portion is configured to be a curved surface forming a part of the pipe-receiving groove of half-circular cross section, the counter pressure member can be formed as a single part with an appropriate shape. Particularly, if the second groove part of half-circular cross section of the body portion of the counter pressure member forms an obtuse angle with a side surface of an end portion of the second groove part formed next to the curved surface portion, a good durability can be ensured. Furthermore, if the counter pressure member is configured to comprise at least a first member and a second member, the rotary support portion constituting a main part of the first member, and the body portion constituting a main part of the second member, the counter pressure member being formed by combining the first member and the second member, when the rotary support portion is worn, only the first member may be changed, so that not only the changing work will be made easily, but also a cost down can be achieved from a long term viewpoint.
On the other hand, if the bend die is configured by an upper section and a lower section divided by a surface perpendicular to the rotary axis, and the fitting protrusion of the counter pressure member is disposed between the upper section and the lower section, although number of parts will be increased comparing the aforementioned configurations, each part can be manufactured with a particular accuracy as required in accordance with a performance of each part, so that each part can be manufactured easily.
In the pipe bend die unit as described above, if the counter pressure member is configured to be divided into at least two members, and it is configured that the at least two members are a mating member including the fitting protrusion and a rotary support member supported to be rotatable about the rotary axis, and that the mating member is detachably connected to the rotary support member, then, only the mating member can be changed as required, so that a countermeasure against its wearing can be made easily. In the case where the clamp member and the counter pressure member comprise a plurality of members divided by a plurality planes perpendicular to the rotary axis, and the plurality of members are configured to be stacked to form the clamp member and the counter pressure member, the clamp member and counter pressure member can be configured by stacking the plurality of parts, and a hinged connection between them can be configured at the same time. If a knock pin fixed to a predetermined position of the clamp member is further comprised, and a position where the counter pressure member abuts on the knock pin is provided for an initial relative position between the clamp member and the counter pressure member, then, the pipe bend die unit, wherein the initial relative position between the clamp member and the counter pressure member is set in advance, can be provided.
And, a pipe bending apparatus according to the present invention comprises the pipe bend die unit configured as described before, a clamp die for clamping the pipe to be bent with the pipe-receiving groove of its bend die, and a pressure die for pressing the pipe toward the bend die, and it is so configured that bending of the pipe is performed by rotating the bend die and the clamp die, with the pipe being pressed in the bending direction by the pressure die. Therefore, the bending of the pipe can be achieved appropriately without causing the crinkling. Furthermore, if a plurality of pipe bend die units are prepared in accordance with various shapes of pipes to be bent, when a pipe is to be bent in a shape, a pipe bend die unit for the shape to be bent may be simply selected and changed, so that the die change can be performed easily, and that no adjustment is required after the die change. Therefore, an automatic die change by means of a robot can be made.
In the pipe bending apparatus as described above, if such a configuration is employed that one part of the fitting protrusion is located at a foreside in an advancing direction of the pipe relative to a position where a bending operation of the pipe is initiated, and an other part of the fitting protrusion is located at a backside in the advancing direction of the pipe relative to the position where the bending operation of the pipe is initiated, smooth bending of the pipe can be achieved.
Particularly, if the counter pressure member has a circularly recessed portion forming the first groove part of half-circular cross section, the fitting recess extending in a peripheral direction on a planar surface perpendicular to the rotary axis, the fitting recess being located at a bottom center of the circularly recessed portion, the first groove part of half-circular cross section being continuous with the circularly recessed portion including a part of the fitting recess, and that the counter pressure member includes a curved surface portion formed on opposite sides of the planar surface, the curved surface portion being configured to contact the circularly recessed portion, the curved surface portion possessing an arch center on an axis offset from the rotary axis and perpendicular to the planar surface in a direction spaced from the rotary axis, the second groove part on the outer peripheral surface of the fitting protrusion possessing the half-circular cross section, with a bottom center of the second groove part being provided on the planar surface perpendicular to the rotary axis, next to the curved surface portion, then, the tip end portion of the curved surface portion of the counter pressure member at the initial position for bending the pipe tightly contacts the circularly recessed portion of the clamp member, whereas a clearance is formed between the curved surface portion of the counter pressure member and the circularly recessed portion at other portions than the tip end portion, even if the relative rotational angle between the clamp member and the counter pressure member is changed. Therefore, the counter pressure member can be assembled with the clamp member easily and appropriately, without causing an interference with the circularly recessed portion, and a durability of the counter pressure member will be improved.
If the counter pressure member served for the pipe bending apparatus as described above has an annular rotary support portion mounted to be rotatable about the rotary axis, and a body portion formed integrally with the rotary support portion, and formed with the groove of half-circular cross section and the curved surface portion, with a part of the rotary support portion formed integrally with the body portion being formed to extend outwardly in a radial direction of the rotary support portion, it can be surely supported to be rotatable about the rotary axis, and it can be hingedly connected with the clamp member easily. In addition, as a part of the rotary support portion is formed to extend outwardly in a radial direction of the rotary support portion, stress concentration applied to the rotary support portion can be relieved, so that durability of the counter pressure member will be improved. As the rotary support portion of the counter pressure member is configured to form the fitting protrusion, and the outer peripheral surface of the rotary support portion is configured to be a curved surface forming a part of the pipe-receiving groove of half-circular cross section, the counter pressure member can be formed as a single part with an appropriate shape.
Furthermore, if the counter pressure member is configured to comprise at least a first member and a second member, the rotary support portion constituting a main part of the first member, and the body portion constituting a main part of the second member, the counter pressure member being formed by combining the first member and the second member, when the rotary support portion is worn, only the first member may be changed, so that not only the changing work will be made easily, but also cost down can be achieved from a long term viewpoint. Also, if the counter pressure member and the clamp member are hingedly connected by an axial member having a central axis passing through the fitting recess, smooth bending of the pipe can be achieved without causing the crinkling.
Furthermore, if the bend die is configured by an upper section and a lower section divided by a surface perpendicular to the rotary axis, and the fitting protrusion of the counter pressure member is disposed between the upper section and the lower section, each part can be manufactured with a particular accuracy as required in accordance with a performance of each part, so that each part can be manufactured easily.
In the pipe bending apparatus as described above, if a knock pin fixed to a predetermined position of the clamp member is further comprised, and a position where the counter pressure member abuts on the knock pin is provided for an initial relative position between the clamp member and the counter pressure member, then, the pipe bend die unit, wherein the initial relative position between the clamp member and the counter pressure member is set in advance, can be provided, and no adjustment after the die change is required. Furthermore, if there is provided a mandrel with a tip end portion thereof being inserted into the pipe, to be driven such that the tip end portion opposes the pressure die within a predetermined rotating region of the bend die, bending work with a small bending radius can be made easily, and limit for bending the pipe can be improved at a large extent.
Hereinafter, will be explained desirable embodiments of the present invention referring to drawings.
According to the present embodiment, the bend die 100 has a clamp member 10 and a counter pressure member 20. As shown in
As shown in
Accordingly, the first groove part 11 possesses a continuous half cylindrical cross section, with a groove part 11a of half-circular cross section formed on the clamp portion 10a and a groove part 11b of half-circular cross section formed on the circularly recessed portion 10b. Furthermore, on the groove part 11a, a plurality of clamp grooves are formed peripherally to ensure holding the pipe (P), in the same manner as the inner peripheral surface of the clamp die 200. And, on a central portion (axial central portion) of the first groove part 11, the fitting recess 12 is formed to extend from a portion next to the groove part 11a by about 270 degree in a peripheral (circumferential) direction of the groove part 11b. Although the clamp member 10 of the present embodiment is formed integrally with the bend die 100 as a part of the bend die 100, it may be made separately and connected to the bend die 100, as described later with reference to
On the other hand, as shown in
The above counter pressure member 20 is formed as shown in
And, an outer peripheral surface 22a of the fitting protrusion 22, i.e., the outer peripheral surface of the rotary support portion 23 is formed into a curved surface as shown in
The clamp member 10 and counter pressure member 20 as configured above are hingedly connected about the rotary axis (A), and rotatably supported relative to each other about the axial member 60 (rotary axis (A)). According to the present embodiment, the clamp member 10 is supported to be rotated against the counter pressure member 20, which is fixed to a predetermined position of a support device (not shown). As shown in
Consequently, with the fitting protrusion 22 of the counter pressure member 20 being fitted into the fitting recess 12 of the clamp member 10, the axial member 60 configuring the rotary axis (A) is inserted through the rotary support portion 23 to be fixed to the base member 13, and fixed to the holding member 70, thereby to configure the bend die 100 as shown in
As shown in
Referring to
Then, with the tip end portion of the pipe (P) being clamped between the clamp member 10 and the clamp die 200, the pipe (P) is forwardly driven, with the body portion of the pipe (P) being pressed to the counter pressure member 20 by the pressure die 300, and also the clamp die 200 and the clamp member 10 are rotated about the rotary axis (A), so that the pipe (P) is bent to be rolled around the outer peripheral surface of the rotary support portion 23 (the outer peripheral surface 22a of the fitting protrusion 22), thereby to form the pipe (P) bent in such a shape as shown in
As described before, the bend die 100 served for the pipe bend die unit of the present embodiment comprises the clamp member 10 and counter pressure member 20, which are hingedly connected about the rotary axis (A), and rotatably supported relative to each other about the rotary axis (A). Therefore, as the pipe (P) is being bent, the clamp member 10 can be rotated relatively to the counter pressure member 20 about the rotary axis (A), with the counter pressure member 20 being pressed by the pressure die 300 through the pipe (P). Consequently, the clamp member 10 is rotated from the initial bending position (as indicated by (S) in
Then, the counter pressure member 10 and the clamp member 20 are hingedly connected, such that the fitting portion (indicated by (F) in
Consequently, although the pipe (P) which was bent by use of the pipe bend die unit of the present embodiment is formed with a thick portion (protruded portion) as shown in
As described above, according to the pipe bending apparatus having the pipe bend die unit of the present embodiment, a smooth bending can be achieved without causing a crinkling. In other words, by appropriately controlling the plastic forming caused by the bending appropriately, the bending of the pipe (P) can be achieved appropriately without causing the crinkling. Consequently, provided that a diameter of a pipe (P) is “d” and a bending radius is “r”, for example, a pipe (P) with such an extraordinarily small bending radius that “r/d” is smaller than 1 can be easily formed. As an alternative to the aforementioned pipe bending apparatus, it may be so configured that the clamp member 10 is fixed, and that the counter pressure member 20 is rotated about the rotary axis (A).
Furthermore, as for the pipe bend die unit installed on the pipe bending apparatus as described above, if a plurality of pipe bend die units are prepared in accordance with various shapes of pipes to be bent, when a pipe is to be bent in a shape, a specific pipe bend die unit for the shape to be bent may be simply selected and changed, so that its die change can be performed easily. As the clamp member 10 and counter pressure member 20 configuring the pipe bend die unit have been placed at the initial relative position, no adjustment is required after the die change. Accordingly, the pipe bend die unit can be used for an automatic pipe bending apparatus, so that an automatic die change can be performed by a robot, which will be described later referring to
According to the embodiment as shown in
Hereinafter, will be explained the configuration of the counter pressure member 20 including the rotary support portion 23, with reference to
As shown in
Particularly, the curved surface portion 20a has a maximum arch of radius (ra) and minimum arch of radius (rb) as shown in
Accordingly, the tip end portion of the curved surface portion 20a of the counter pressure member 20 tightly contacts the circularly recessed portion 10b at the initial position (S) for bending the pipe (P), and the clearance (G) is formed between the curved surface portion 20a and the circularly recessed portion 10b, as described above, at other portions than the tip end portion. As a result, the counter pressure member 20 can be easily and appropriately assembled with the clamp member 10, which is formed by the upper die 40 and lower die 50 in this embodiment, without causing an interference with the circularly recessed portion 10b. As the counter pressure member 20 does not slide on the circularly recessed portion 10b at other portions than the tip end portion, no frictional loss will be caused, so that a durability of the counter pressure member 20 in particular will be improved. When the curved surface portion 20a is formed, it should be avoided to employ any arch center other than the axis (OC) as described above, because otherwise the appropriate contact will not be obtained. For example, if the arch center is positioned on such an axis (not shown) that is perpendicular to the plane (H) and offset in the direction spaced from the rotary axis (A), and also offset in the direction perpendicular thereto, any appropriate clearance will not be provided.
According to the present embodiment, the counter pressure member 20 has a support member 26 as shown in
As shown in
The above-described rib 23a is provided for relieving stress concentration applied to a bottom portion of the rotary support portion 23 at a boundary with the curved surface portion 20a, because it is not possible to thicken the bottom portion more than is necessary, in order to avoid any interference with other devices. For example, when the pipe (P) is bent, a load (L) is supposed to be applied to the rotary support portion 23 as indicated by a blank arrow in
According to the counter pressure member 20 of the present embodiment, a plan view of which is shown in
As shown in
Although the counter pressure member 20 has the rotary support portion 23 and the main body portion 24 integrally formed therewith as described above, a large load is applied to the rotary support portion 23 through the pipe (P) to be bent, whereby the wear is unavoidable, so that its replacement will be required after a long term use of it. In view of this, it may be so configured that the counter pressure member 20 to be fixed to the support member 26 is further divided into a first member 20x, which includes a main part of the rotary support portion 23 and connecting portion 25, and a second member 20y, which includes a part 23y of the rotary support portion 23 and the main body portion 24, and that they are connected by bolts for example, thereby to configure the counter pressure member 20. Consequently, in the case where the rotary support portion 23 is worn, only the second member 20y including the worn part 23y may be replaced, so that the replacement is easily made, and that an inexpensive counter pressure member 20, and therefore an inexpensive bend die unit 100, can be provided in view of a long term use of it, to result in a cost down.
As shown in
Or, as shown in
Or, as shown in
Furthermore, as shown in
Next will be explained about an example of a production line for an automotive pipe bending apparatus using the pipe bend unit as disclosed in
According to the robot device 2, the clamping jig (MH) is mounted on a tip end of a robot arm 2a through an auto tool changer (ATC). On the opposite ends of the clamping jig (MH), mounted are clamp mechanisms for clamping the pipe (P) to be detachable, one of which is capable of clamping the pipe (P) to be formed, and the other one of which is capable of clamping the formed pipe (P).
Next,
Consequently, a new unit (DU) is removed from the unit table 5 by means of the robot arm 2a, and transferred to the pipe bending apparatus 1 as shown in
The die change of the unit (DU) for the pipe bending apparatus 1, i.e., changing and installing the unit (DU), and operation of the pipe bending apparatus 1, i.e., bending the pipe (P) can be automated, and the unit (DU) can be provided with intelligence to expect a more advanced automation. For example, it may be so configured that various kinds of sensors or cameras are installed on the unit (DU), or a laser beam is applied, and that working data are measured at real time to be stored in a memory tip or the like embedded in the unit (DU). Or, it may be so configured that a communication means embedded in the unit (DU) is transmitting serial working data to a line-controller or the like, to store the data therein. In the case where it is so configured that the working data are stored in the memory tip or the like embedded in the unit (DU), the working data may be transmitted by wire to the line-controller or the like through the robot device 2, or may be stored in the pipe bending apparatus 1. Furthermore, it may be so configured that a remote counting of the formed products under a license for bending the pipe by means of the unit (UD) may be performed by transmitting the working data through the aforementioned communication means. According to the automatic operation and/or automatic die change, therefore, the positions or states of the unit (DU) can be traced sequentially, and also more effective working conditions, automatic operation and/or automatic die change can be provided by analyzing the stored data, thereby to contribute an automatic factory system. According to the automatic die change line as described above, only the unit (DU) was selected as a target for the die change, while it may be so configured that the automatic change of the pressure die, clamp die, and mandrel as well can be made adequately by robot means depending on difference of diameters of the pipes to be formed according to the die change, or difference in thickness of the pipes (with the same diameter).
Next,
According to the present invention, it is so configured that the bend die 100 of the aforementioned embodiment, especially the counter pressure member 20 hingedly connected to the clamp member 10 functions as that mechanism, so as to be capable of opposing the large load by the pressure die 300 sufficiently. As shown in
Also, as enlarged in
In contrast, according to the rotary bending apparatus using the prior bend die and wiper for preventing the crinkling, it is arranged in such a manner that the wedge shaped wiper (W) will squeeze into a clearance between the pipe (P) and bend die (D) as shown in
According to the prior rotary bending apparatus, although the bending of the pipe (P) is performed in the state that the mandrel (M) has been inserted into the pipe (P), and the friction force (FR) is caused as shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| 2014-119613 | Jun 2014 | JP | national |
| 2014-263966 | Dec 2014 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2015/066571 | 6/9/2015 | WO | 00 |
