JP2003320490A - Link press - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a link press which can be processed under a high press load and can improve the cycle time of the processing even when a motor of a relatively small output is used, is excellent in controllability, in which an error in the positional relation among constituent parts of a link mechanism is prevented, and the processing precision is easily maintained. <P>SOLUTION: The link press is equipped with the link mechanism 1 for converting a rotary motion to a straight-line motion, and a ram 6 moving up and down with the straight-line motion for press processing. A driving transmission system 14 for transmitting drive from a motor 13 to a crankshaft 3 is disposed. This driving transmission system 14 can controllably driving transmit the up and down motion of the ram 6 by rotational control of the motor 13. The crankshaft 3 and a pivot shaft 12 of a constraint link 8 are disposed in a crankshaft supporting hole and a constraint link supporting hole provided on the same board part 9a in a frame 9, respectively. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a punch press using a link mechanism as a slide drive mechanism and other link presses.

[0002]

2. Description of the Related Art In mechanical punch presses, a crank mechanism is generally used as a slide drive mechanism for converting a rotating operation of a motor into an elevating operation of a ram. In addition, a flywheel is used to switch between driving and stopping the ram by connecting and disconnecting the rotation of the flywheel when the clutch is turned on and off. With the crank mechanism,
The curve of the ascending / descending speed of the ram is symmetrical with respect to the bottom dead center at the time of descending and ascending, and the descending speed and the ascending speed are the same. However, in general press working such as punching, when the ram descends, it is preferable to make it low speed because of the requirement of noise reduction and press load, but when ascending, there is no particular limitation, so it is desirable to be high speed. With a crank mechanism in which the descending speed and the ascending speed are the same, it takes more time than necessary to ascend, and the punching cycle time becomes long.
Recently, a servo motor is used as a drive source, and a ram is raised and lowered via a crank mechanism without providing a flywheel. If a servo motor is used, it is possible to freely change the speed during the stroke of the ram, to increase the descending speed and decrease the ascending speed. However, the capacity of the motor changes depending on the rotation speed, and in order to make the best use of the capacity of the motor, it is necessary to operate within the range of the optimum motor rotation speed according to the motor characteristics. By controlling the motor rotation speed to change the speed when the ram descends and when it rises, it is not possible to make full use of the capacity of the motor, and in order to obtain the necessary press load and increase the speed when climbing, A large motor is required.

Therefore, the inventor of the present invention has conducted various studies on what is slowed down when moving down and fast when moving up by selecting an appropriate slide mechanism. BACKGROUND ART Conventionally, a link press has been used for a long time as a slide mechanism used in a press device for plastic working such as cold extrusion and upsetting of metal (for example, Japanese Patent Publication No. 3-42159). The link press has a swing pin connected to a crank pin of a crank mechanism, a connecting rod connected to the swing link, and a restraint link connected to the swing link. The crankshaft is driven by a motor via a flywheel. According to the link press, the operation characteristic that the ram speed is slow when descending and fast when ascending is obtained by the action of the restraining link.

However, the conventional link press is used for improving the working quality of plastic working such as cold extrusion by utilizing a very slow descending operation near the bottom dead center thereof. There is no application example to a punch press that requires operating characteristics different from those of processing. Also, because it has a flywheel that stores the motor output as inertial energy,
Lack of controllability. In addition, in the conventional link press,
The crankshaft and the restraint link that make up the crank mechanism,
They are installed on separate members of the frame. For example, the restraint link is rotatably supported by a bracket provided on the frame. Therefore, due to deformation due to the action of load, assembly error, and the like, a subtle error occurs between the axial center of the crankshaft and the rotation center of the restraint link, and this error affects the operation of the ram and reduces the machining accuracy. There is a fear. If a rigid bracket is used, there is a problem of increased weight and increased cost.

The object of the present invention is to enable the processing by a high press load and the improvement of the cycle time of the processing even if a motor having a relatively small output is used, and the positional relationship between the components of the link mechanism has an error. It is an object of the present invention to provide a link press that does not easily occur and is easy to maintain processing accuracy.

[0006]

A link press according to the present invention includes a motor, a link mechanism for converting a rotary motion transmitted from the motor through a drive transmission system into a linear motion, and installed below the link mechanism. And a ram that moves up and down for press working by the linear movement. The link mechanism has a crank member having a crank shaft and an eccentric shaft portion, and first to third connecting portions that rotatably connect to each other so as to be located at respective apexes of a triangle, and the first connecting portion. Is a swinging link connected to the eccentric shaft portion of the crank member, a connecting rod having both ends connected to the second connecting portion and the upper end of the ram, and a base end rotatably connected to the frame and a tip end. Is connected to the third connecting portion of the swing link to restrain the swing of the swing link. The crankshaft and the base end of the restraint link are respectively installed in a crankshaft support hole and a restraint link support hole provided in the same plate portion of the frame. The plate portion may be a plate material or a plate-shaped portion that is a part of the frame. The plate portion preferably has a predetermined thickness.

The operation of this configuration will be described. Due to the rotation of the crankshaft, the swing link performs a combined operation of an orbital motion along the swirl orbit of the shaft center of the eccentric shaft portion and a rotation motion that is swung forward and backward due to the connection of the restraint link. Due to the revolving motion of the rocking link, the connecting rod connected to it moves up and down.However, because of the above-mentioned rotation motion, the lowering position of the connecting rod, that is, the ram position lifting speed curve is not a quasi-sine curve. Instead, it becomes asymmetrical when descending and when ascending. Which of the descending speed and the ascending speed becomes faster is determined by a combination of various elements such as the fulcrum position and the length of the restraint link. Therefore, by properly designing each element, the restraint link regulates the swing of the swing link so that the descending motion of the ram when the crankshaft is rotated in one direction at a constant speed is slower than the ascending speed. can do. In this way, by slowing the descending speed, it is possible to process with a high press load and to increase the ascending speed even if a motor with a relatively small output is used.
The processing cycle time is improved. Since the above-mentioned speed change is given while the motor speed remains constant, for example, by interposing a speed reducer having an appropriate speed reduction ratio, it is possible to operate at the motor rotation speed that maximizes the motor output according to the motor characteristics. This also enables the use of a low power motor. It should be noted that the drive transmission system may be one that transmits the rotational drive of the motor to the crankshaft so that the raising / lowering operation of the ram can be controlled by controlling the rotation of the motor. In that case, the motor and the crankshaft are connected through a drive transmission system that does not have an element for imparting inertia such as a flywheel, and therefore, for example, when changing the ram speed by controlling the rotation speed of the motor, etc. Excellent controllability.

The axial center of the crankshaft and the rotation center of the base end of the restraint link are both rotation centers for fixing the position,
When the relationship between these two positions changes, the operation of the link mechanism changes, resulting in a difference in the raising / lowering operation of the ram. But,
Since both the crankshaft and the base end of the restraint link are respectively installed in the crankshaft support hole and the restraint link support hole provided in the same plate portion of the frame, they are supported by using separate members such as brackets. Compared to the one that does, the positional relationship such as distance is hard to change even when a large load is applied. In other words, the part of the plate material is interposed between both support holes, and the load that changes the interval between both support holes is in the direction along the surface of the plate material, so high rigidity is obtained and the distance between the holes changes. hard. Further, since it is only necessary to form holes for the crankshaft support hole and the restraint link support hole in the plate portion, the processing can be performed easily and each support hole can be formed with high accuracy, and there is little problem of assembly error. Therefore, the operation of the link mechanism can be obtained with high accuracy, and the ram can be moved up and down to a constant level, and the hoisting range can be obtained.

The frame has a pair of plate portions facing each other on both front and rear sides in the axial direction of the crankshaft, the crank member extends on both sides of the eccentric shaft portion, and the crankshaft extends on both sides. The portions are respectively supported by crankshaft support holes provided in the front and rear plate portions. The restraint link is via a fulcrum shaft inserted across the restraint link support holes provided on the plate portions on both sides,
The base end is rotatably supported. The fulcrum shaft may be rotatably installed or fixedly installed. In this way, the plate parts facing the front and back are provided,
When the crankshaft and the fulcrum shaft of the restraint link are installed on both plate portions, both the crankshaft and the fulcrum shaft of the restraint link support both ends, and are strong against bending due to acting load. Therefore, it is easier to secure the operation accuracy of the link mechanism, and the processing accuracy is improved.

The frame includes plate portions on both front and rear sides,
It may be configured by a box body including connecting plate portions that connect the front and rear plate portions at both left and right ends. The front and rear plate parts and the left and right connecting plate parts are made of separate plate materials, and even if they are joined together by welding or the like, the whole or a part of the box-shaped frame May be an integral member, and each of the plate portions may be a component of a different surface of the frame. If it is made of a box, it will be more resistant to deformation, the positional displacement of both ends of each axis will be prevented, and further improvement in processing accuracy can be expected.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram combining a link mechanism and a block diagram showing a conceptual configuration of a control system in this link press. The control system will be described later. The link press includes a motor 13, a link mechanism 1 for converting a rotational motion transmitted from the motor 13 via a drive transmission system 14 into a linear motion, and a link mechanism 1 installed below the link mechanism 1 for performing the linear motion. And a ram 6 that moves up and down for press working. The link mechanism 1 includes a crank member 2 having an eccentric shaft portion 4 that is eccentric with respect to the axis of the crank shaft 3.
And a swinging link 5 connected to the eccentric shaft portion 4, a connecting rod 7, and a restraining link 8. The crankshaft 3 is rotatably installed on the frame 9 and serves as a shaft that receives a rotational driving force. The eccentric shaft portion 4 is the crankshaft 4
It has a larger diameter than the shaft. The eccentric shaft portion 4 may have a smaller diameter than the crankshaft 3 and may be integrated with the crankshaft 3 via a crank arm (not shown), instead of having the large diameter as described above. Ram 6 is
It is a member for raising and lowering a press working portion such as a punch tool, and is installed on the frame 9 via a guide member 10 so as to be able to move up and down. The ram 6 is directly below the crankshaft 2.

The swinging link 5 has first to third connecting portions P1 to P3, and the crank member 2 is connected to the first connecting portion P1.
Is connected to the eccentric shaft portion 4. Each connecting portion P1-3
Each of them is a connecting portion for rotatably connecting and is located at each vertex of the triangle T, as schematically shown in FIG. This triangle T is an arbitrary triangle in a plane perpendicular to the axis of the crankshaft 3. In FIG. 1, the connecting rod 7 is the second connecting portion P of the swing link 5.
The upper end is connected to 2 and the lower end is rotatably connected to the upper end of the ram 6 via a pin 11. The restraint link 8 has a base end rotatably supported by the frame 9 via a fulcrum shaft 12,
The tip is connected to the third connecting portion P3 of the swing link 5. The restraint link 8 is arranged such that the swing center, which is the axial center of the fulcrum shaft 12, and the third connecting point P3 are distributed to both sides of the crankshaft 3. The both sides are both sides in a plane perpendicular to the axis of the crankshaft 3, and may be on both sides in the left-right direction or both sides in the front-rear direction with respect to the entire link press.

As shown in FIGS. 4 and 5, the crankshaft 3 has a drive transmission system 14 connected to an output shaft (not shown) of the motor 13.
Are connected via. The drive transmission system 14 is the motor 1
It is assumed that the rotation drive of the ram 6 can be controlled by the rotation control of the motor 3, and the rotational drive of the motor 13 can be transmitted to the crankshaft 3. Therefore, the drive transmission system 14 is a means for transmitting the torque of the motor 13 without interposing components such as a flywheel for imparting inertia. In this embodiment, the drive transmission system 14 includes a speed reducer 15 and a coupling 16 that connects the output shaft of the speed reducer 15 to the crankshaft 3.
A servo motor is used as the motor 13. The speed reducer 15 and the motor 13 may be integrated with each other to form a motor with a speed reducer.

FIG. 2 shows a broken side surface of the link mechanism 1.
The crankshaft 3 extends on both sides of the eccentric shaft portion 4, and is rotatably supported by the frame 9 via bearings 17 on both sides. In the swinging link 5, the inner diameter surface of the connecting hole forming the first connecting portion P1 is fitted to the outer periphery of the eccentric shaft portion 4 via the liner 18. The second connecting portion P2 of the swing link 5 and the connecting rod 7 are connected by a connecting pin 19.

As shown in FIG. 5, the frame 9 is an independent link mechanism frame for supporting the link mechanism 1,
It is attached to the tip of the upper frame portion 22a of the main body frame 22. The frame 9 is composed of a box body as follows. That is, the frame 9 includes a pair of plate portions 9 facing each other on both front and rear sides in the axial direction of the crankshaft 3.
c, 9a, and a connecting plate portion 9d (see FIG. 12) that connects the front and rear plate portions 9c, 9a at the left and right ends, respectively. The rear plate portion 9a is a mounting board 9aa.
And a support plate 9ab stacked on the upper part of the front surface thereof has a double structure. The other plate portions 9c, 9d are made of a single plate material, and the plate portions 9a, 9c, 9d are joined to each other by welding. The upper surface of the frame 9 is open, and the lower surface has a plate portion 9
e is provided. The ram opening 40 is provided on the lower plate portion 9e, and the guide member 10 of the ram 6 is installed. The plate portion 9c on the front surface of the frame 9 is provided only on the upper portion, and the lower portion of the front surface is an open portion 41.

As shown in FIG. 12, the front and rear plate portions 9c and 9a of the frame 9 have a crankshaft support hole 43 and a restraint link support hole 44. The crankshaft support hole 43 and the restraint link support hole 44 in the rear plate portion 9a are both provided in the support plate 9ab, and the mounting board 9aa is provided.
Is provided with a crankshaft insertion hole 43A aligned with the crankshaft support hole 43. This crankshaft support hole 43
The portions of the crankshaft 3 on both sides of the crank member 2 are respectively supported. The crankshaft 3 is, as shown in FIG.
It is rotatably supported in the crankshaft support hole 43 via the bearing 17. The bearing 17 has a cylindrical bearing housing 17a that fits in the crankshaft support hole 43, and is a flange portion provided on the bearing housing 17a, and is attached to each plate portion 9a, 9c by a fastener 45 such as a bolt. It is fixed. The bearing 17 is, for example, a journal bearing, and includes the bearing housing 17a and a sleeve 17b fitted in an inner diameter hole thereof.

The fulcrum shaft 12 of the restraint link 8 in FIG.
Both ends are rotatably supported in the restraint link support holes 44 shown in FIG. 12 via bearings (not shown). Fulcrum shaft 1
2 may be fixedly supported by the restraint link support hole 44. When the fulcrum shaft 12 is fixedly installed in the restraint link support hole 44, the restraint link 8 is rotatably attached to the fulcrum shaft 12.

As shown in FIG. 4, the frame 9 is provided with a motor support member 23, and the motor 13 is installed on the motor support member 23. Therefore, the motor 9
Is removably assembled to the main body frame 22 together with the link mechanism frame 9 in which the link mechanism 1 is installed. The motor support member 23 is installed on the back surface of the rear plate portion 9a of the frame 9.

As shown in FIG. 5, the body frame 22 is
The side surface is C-shaped, and the opening 24 is a space into which the plate work and the tool support enter. The body frame 22 has a pair of opposing side plates, and only one opposing side plate is shown in FIG. In the upper frame portion 22a, opposite side plates on both sides are joined to each other by an upper frame lower surface plate 25 and an intermediate reinforcing plate 26.

10 and 11 are respectively a plan view and a side view of the whole link press provided with the above-mentioned link mechanism 1. As shown in FIG. The body frame 22 is covered with a body cover 30. In addition to the link mechanism 1, a tool supporting means 28 and a work feeding means 29 are installed on the main body frame 22. The tool supporting means 28 has a plurality of punch tools 31 and die tools 32 mounted thereon, and is capable of indexing arbitrary tools 31, 32 (FIG. 11) at the press working position Q by the ram 6. The tool supporting means 28 is composed of upper and lower turrets 28a and 28b on which a punch tool 31 and a die tool 32 are mounted, respectively. Work feeding means 2
The reference numeral 9 designates a plate work W on the table 33 in two orthogonal directions (X-axis, Y-axis) so that an arbitrary portion comes to the press working position Q.
Axis) to move. The work feeding means 29 is
It has a carriage 34 that moves back and forth (Y-axis direction), and a cross slide 35 that is mounted on the carriage 34 and moves left and right (X-axis direction). To hold. By moving the carriage 34 back and forth and moving the cross slide 35 left and right, the plate work W is fed in the biaxial directions.

The operation of the above configuration will be described. The link mechanism 1 of FIG. 1 performs the following operation, as can be seen by referring to the schematic view of FIG. 7. When the crank shaft 3 is rotated by driving the motor, the center of the eccentric shaft portion 4 of the crank member 2 is, as shown in FIG. 7, a circular orbit C1 centered on the shaft center of the crank shaft 3.
Draw. The oscillating link 5 includes the eccentric shaft portion 4 and the first connecting portion P.
Since it is rotatably connected at 1, the above-mentioned circumferential orbit C1
Perform an orbital movement in line with. Since the swing link 5 is connected to the restraint link 8 by the third connecting portion P3, its operation is restricted, and the first connecting portion P1 is associated with the revolving movement.
Performs a rotational movement that is swung in the normal and reverse directions. Due to this combined movement of the revolution movement and the rotation movement, the second connecting portion P2, which is the connecting portion of the swinging link 5 with the connecting rod 7, is
As shown in the figure, it moves along an oblique elliptical orbit C2.
The ram 6 is supported so that it can be raised and lowered only, and is connected to the second connecting portion P2 of the swing link 5 via the connecting rod 7, so that the second connecting portion P2 draws an elliptical orbit. Moves up and down by. The speed of the raising / lowering operation of the ram 6 is asymmetric between the descending time and the ascending time, as shown by the curve H in FIG. Further, the crank angle θ _BDC when the ram 6 reaches the bottom dead center BDC is a position deviated from 180 °. A curve J also shown in the figure shows the vertical displacement of the ram in a general crank mechanism and is symmetrical.

The elements that affect the operation of the link mechanism 1 are the following eight elements shown in FIG. The crank length (eccentricity) r, the length w of the restraint link 8, the length L of the connecting rod 7, the opening angle α between the connecting portions P2 and P3 of the swing link 5, and the connecting portion P1 of the swing link 5. Connection part P
The lengths a and b between 2 and P3, and the X-coordinate Ex and the Y-coordinate Ey of the fulcrum position of the restraint link 8. The center of coordinates is the axis of the crankshaft 3. As a condition for establishing the link mechanism 1, the rotation center of the crankshaft 3-the connecting portion P1-
It is necessary to establish a four-joint rotary chain that is established by using the fulcrum shaft 12 of the connecting portion P3-restraining link 8 as a connecting point between the joints, and the shortest joint is defined as the crank length r, and each of the following expressions must be satisfied. . As A = √ (Ex ^ 2 + Ey ^ 2), r + a ≦ w + A r + w ≦ a + A r + A ≦ a + w This is known as Grashof's theorem. , The displacement curve of the ram 8 can be freely designed.

Which of the descending speed and the ascending speed becomes faster is determined by the combination of the motor rotating direction and the above-mentioned respective elements. Therefore, assuming that the motor rotation direction is constant, by appropriately designing the respective elements, it is possible to perform an operation in which the descending speed of the ram 6 when the motor 13 rotates at a constant speed becomes slower than the ascending speed. By slowing the descending speed in this way, machining can be performed with a high press load even when the motor 13 having a relatively small output is used, and the ascending speed is increased, so that the machining cycle time is improved. As shown in FIG. 9 by comparing the crank type press and the link type press, when the cycle time is “10”, both the descending time and the ascending time are “5” in the crank type as shown in FIG. However, in the link type, it is possible to design so that the falling time is “7” and the rising time is “3” as shown in FIG. When the link mechanism 1 is designed in this way, the ram speed of the descending operation becomes 5/7 as slow as that of the crank type, and the press load becomes 7/5 as much, and even if the same motor is used, 40%
The press load can be improved. Since no work is performed when the ram 6 is raised, even if the force is weak, it does not affect the machining.

Further, since the above-mentioned speed change is given while the motor speed is kept constant, the speed reducer 15 having an appropriate deceleration ratio is provided.
By interposing (FIG. 4), it is possible to operate at the motor rotation speed that maximizes the motor output according to the motor characteristics. This also makes it possible to use the motor 13 with a small output.
Further, since the motor 13 and the crankshaft 3 are connected via the drive transmission system 14 in which an inertia imparting system such as a flywheel does not intervene, the controllability of changing the ram speed by controlling the rotational speed of the motor 13 is excellent.

When the motor 13 is a servo motor,
Since the motor speed can be freely changed, the speed during the up-and-down stroke of the ram 6 can also be changed, and machining according to various requests can be performed. That is, the crank member 2 is used as a speed curve when the motor 13 is rotated at a constant speed.
Based on the speed curve according to the operation of the link mechanism 1 composed of the rocking links 5, the restraint links 8 and the like, the speed when the punch tool 31 comes into contact with the plate work W is changed by changing the motor speed. It is also possible to further reduce the noise to further reduce the noise, and to further increase the speed at the time of rising. Further, the ram 6 can be stopped at an arbitrary height.

When punching is performed in this link press, as shown in FIG. 8, the punching section M, which is a section used for punching the plate work W, is an intermediate section of the descending process of the ram lifting stroke. There is a need. The intermediate section, which is the punching section M, is a section in which the curve H of the displacement of the ram 6 with respect to the crank angle is substantially linear. The lower limit position H ₁ of the punching section M is slightly above the die height DH. In the link press, if the motor speed is constant, as can be seen from the ram displacement curve H in the same figure, the curve becomes a gentle curve near the top dead center TDC, becomes a straight line in the middle section, and again near the bottom dead center BDC. It becomes a gentle curve. The speed near the bottom dead center BDC is the slowest, and therefore the largest press load is obtained near the bottom dead center BDC. In the conventional linking press for forming, a large press load near the bottom dead center BDC is used for forming. However, in the case of punching, a stroke is required below the lower surface of the plate work W in order to surely drop the punch residue. On the other hand, when the punching section M is the middle section of the stroke, a sufficient stroke can be obtained below the lower surface of the plate work W to reliably drop the punching residue, and the originally small punch load in the middle section. Can be supplemented by the link mechanism 1. In other words, for this reason, the vicinity of the bottom dead center BDC where a large press load can be obtained cannot be used, but it can be used more efficiently than the conventional symmetrically operating crank mechanism. Punching requires a large press load and high-speed processing. Further, in punching, the higher the punching speed is, the better the working quality is. If the punching section M is an intermediate section, the punching speed required for the working quality can be obtained without waste. In this way, when applied to a punch press, the action of the link mechanism 1 can be effectively used in a usage pattern different from that of the conventional link press for molding.

Further, in this link press, the frame 9 for supporting the link mechanism 1 has the crankshaft 3 and the base end of the restraint link 8 which are provided in the same plate portions 9a and 9c as the crankshaft support holes 43 (see FIG. 12) and the restraint link support holes 44, respectively, the positional relationship such as the distance is less likely to change even when a large load is applied, as compared with the case where a separate member such as a bracket is used for supporting. In other words, since the part of the plate material is interposed between the support holes 43 and 44 and the load that changes the distance between the support holes 43 and 44 is in the direction along the surface of the plate material, high rigidity is obtained and both support Holes 43, 4
It is difficult for the distance between 4 to change. Further, since it is only necessary to form holes for the crankshaft support hole 43 and the restraint link support hole 44 in the plate portions 9a and 9c, the support holes 43 and 44 can be formed easily and accurately, resulting in an assembly error. There are few problems. Therefore, the operation of the link mechanism 1 can be accurately obtained, and the ram 6 can have a constant ascending / descending operation and an ascending / descending range, so that the processing accuracy can be maintained with high accuracy.

The frame 9 has a plate portion 9 facing front and back.
c, 9a, and the crankshaft 3 on both side plate portions 9c, 9a.
Further, since the restraint link fulcrum shaft 12 is installed, both of these shafts 3 and 12 support both ends, and are strong against bending due to acting load. Therefore, it is easier to secure the operation accuracy of the link mechanism 1 and the processing accuracy is improved. Further, since the frame 9 is a box body, it is more resistant to deformation, positional deviations of both ends of the shafts 3 and 12 are prevented, and further improvement in processing accuracy can be expected. In addition, by making the frame 9 a box, the link mechanism 1
It can be handled as one independent machine assembled together with, and a procedure for assembling this independent machine together with the main frame 22 of the press machine together with the frame 9 can be achieved.
Good handleability.

[0029]

The link press of the present invention employs a link mechanism having a crank member, a swinging link, a connecting rod, and a restraining link. Therefore, even if a motor with a relatively small output is used, processing with a high press load, It is also possible to improve the processing cycle time. Further, since the crankshaft and the base end of the restraint link are respectively installed in the crankshaft support hole and the restraint link support hole provided in the same plate portion of the frame, there is an error in the positional relationship between the components of the link mechanism. Is less likely to occur, and the processing accuracy can be maintained easily. When the plate parts facing the front and back are provided on the frame and the crank shaft and the fulcrum shaft of the restraint link are installed on both plate parts, both the crank shaft and the fulcrum shaft of the restraint link support both ends and Strong against bending. Therefore, it is easier to secure the operation accuracy of the link mechanism, and the processing accuracy is improved. If the frame is composed of a box body consisting of front and rear plate parts and connecting plate parts that connect the front and rear plate parts at the left and right ends, respectively, it becomes more resistant to deformation and the position shift of both ends of each shaft Is also prevented, and further improvement in processing accuracy can be expected.

[Brief description of drawings]

FIG. 1 is a cutaway front view of a link mechanism in a link press according to an embodiment of the present invention.

FIG. 2 is a cutaway side view of the link mechanism.

3A and 3B are respectively a front view and a side view of the link mechanism.

FIG. 4 is a side view showing a connected state of the link mechanism and the motor.

FIG. 5 is a perspective view showing a portion where the link mechanism and the motor are installed in a main body frame.

FIG. 6 is a perspective view of the link mechanism.

FIG. 7 is an explanatory diagram of an operation model of the link mechanism.

FIG. 8 is a graph showing a relationship between a crank angle and a ram displacement in the link mechanism.

FIG. 9 is a graph comparing ram displacement processes of the link mechanism and the crank type press.

FIG. 10 is a plan view showing the entire link press of the same embodiment.

FIG. 11 is a side view showing the entire link press.

FIG. 12 is an enlarged perspective view of a frame of the link mechanism.

[Explanation of symbols] 1 ... Link mechanism 2 ... Crank member 3 ... crankshaft 4 ... Eccentric shaft 5 ... Swing link 6 ... Ram 7 ... Connecting rod 8 ... Restraint link 9 ... Frame 9a, 9c ... Plate part 10 ... Guide member 11 ... pin 12 ... fulcrum axis 13 ... Motor 14 ... Drive transmission system 15 ... reducer 43 ... Crankshaft support hole 44 ... Restraint link support hole

Claims (3)

[Claims] 1. A motor, a link mechanism for converting a rotary motion transmitted from the motor via a drive transmission system into a linear motion, and a link mechanism installed below the link mechanism for press working by the linear motion. The link mechanism includes a ram that moves up and down, and a crank member having a crank shaft and an eccentric shaft portion, and first to third connecting portions that rotatably connect the crank member and the crank member. A swing link having a first connecting portion connected to the eccentric shaft portion of the crank member; a connecting rod having both ends connected to the second connecting portion and the upper end of the ram; and a base end having a frame. A restraint link that is rotatably coupled to the crankshaft and has a tip coupled to a third coupling portion of the swing link to regulate swing of the swing link, the crankshaft and a base end of the restraint link. The above Link press, characterized in that installed respectively on the same plate crankshaft provided in the unit support hole and the restraining link support hole in frame. 2. The frame has a pair of plate portions facing each other on both front and rear sides in the axial direction of the crankshaft, and the crank member has the crankshaft extending on both sides of an eccentric shaft portion. The crankshaft portions are respectively supported by crankshaft support holes provided in the front and rear plate portions, and the restraint link is a fulcrum shaft inserted between the restraint link support holes provided in the plate portions on both sides. The link press according to claim 1, wherein the base end is rotatably supported via the. 3. The link press according to claim 2, wherein the frame is composed of a box body including plate portions on both front and rear sides and connecting plate portions connecting the front and rear plate portions at left and right ends, respectively.