EP1063030A2

EP1063030A2 - Press device

Info

Publication number: EP1063030A2
Application number: EP99113861A
Authority: EP
Inventors: Matsuoka Mitsuo
Original assignee: Umix Co Ltd
Current assignee: Umix Co Ltd
Priority date: 1999-06-25
Filing date: 1999-07-15
Publication date: 2000-12-27
Also published as: JP2001001046A; EP1063030A3; JP3072095B1

Abstract

It is a purpose of the present invention to provide a press device of low cost comprising a sliding cam base, a sliding cam that is guided by the sliding cam base and to which processing members such as a punch are attached, an energizing body provided between the sliding cam base and the sliding cam for energizing the sliding cam, and an operating cam abutted against the sliding cam for driving the sliding cam, wherein the sliding cam can be held by the sliding cam base to enable accurate press processing free of warps or rolling.

For this purpose, it has been provided for a press device of low cost comprising a sliding cam base, a sliding cam that is guided by the sliding cam base and to which processing members such as a punch are attached, an energizing body provided between the sliding cam base and the sliding cam for energizing the sliding cam, and an operating cam abutted against the sliding cam for driving the sliding cam, wherein the press device is arranged in that the sliding cam is provided in a freely slidable manner between two guide posts of circular section suspended from the sliding cam base and separated from each other by a specified distance, and wherein one surface of the sliding cam base is formed as a V-shaped groove and a surface of the sliding cam opposing this surface of the sliding cam base is formed, at the operating cam thereof, with an angular guide portion abutting the V-shape groove.

Description

The present invention relates to a press device.

A press device generally performs presswork such as boring or molding by respectively attaching a lower die to a bed and an upper die to a ram of a press machine wherein the upper die performs rising/descending movements. Processing in lateral directions is performed by transforming, by the use of a cam member, the processing force in vertical directions that is provided by the upper die rising and descending in vertical directions.

These actions will now be explained based on an example in which boring of a side wall of a work is performed utilizing a press device comprised with a cam member.

As shown in Fig. 9 and Fig. 10, a positioning member 104 is provided as to be extruding from a lower die 101 for positioning a work W. A passive cam 107 comprising a punch 106 is provided in a slidable manner at a position at which it opposes a punching hole 105 on a side wall of the work W. A heel 108 is fixedly attached in a rear portion of the passive cam 107. For energizing the passive cam 107 in a returning direction after completion of boring the work W, the following arrangements are made: a coil spring 109 is screwed to the passive cam 107 and is outwardly fitted to a tip portion side of a rod 110 that is piercing through the heel 108, while one end of the coil spring 109 is abutted against the heel 108, and to the other end of the coil spring 109, a nut 112 is screwed with a washer 111 provided intermediately. An operating cam 118 is provided in an extruding manner at an upper die 116 at a position at which it opposes the passive cam 107.

When the upper die 116 is descended, the operating cam 118 forces the passive cam 107 to move forward against the energizing force of the coil spring 109 whereby the hole 105 is formed on the work W through the punch 106 and a die 125, and when the upper die 116 is lifted, the passive cam 107 is retracted by the energizing force of the coil spring 109.

In case boring of a side wall of the work W is to be performed, the passive cam 107 provided with the punch 106 performs approaching and receding movements with respect to the work W so as to perform sliding movements above the lower die 101. The sliding movements of the passive cam 107 need to be accurate since boring is performed by the punch 106 and the die 125, and for this reason, a flanges 121 are provided in an extruding manner from both sides of a lower portion of the passive cam 107, and a lateral guide plate 122 and upper guide plate 123 for guiding the flanges 121 are fixed to the lower guide 101.

In the above-described press device, the lateral guide plates 122 are arranged for guiding a side surface of the flanges 121 extruding from both side of a main body of the passive cam 107a, and the upper guide plates 123 for guiding an upper surface of the flanges 121, for making the passive cam 107 perform repetitive, sliding movements between specified positions. By the provision of the flanges 121, lateral guide plates 122 and upper guide plates 123, there are formed, on both lateral sides of the main body portion 107a of the passive cam 107, extruding portions by length L, respectively, wherein the length L is usually in a range between 100 to 150 mm at minimum so that the whole arrangement requires a large space above the lower die 101 of the press device.

In this manner, the provision of a cam mechanism will occupy a large space within a press device. Due to the large space that is required for the provision of such a cam mechanism, it may be that some required members may not be able to be included in the press device since the size of the whole press device is restricted by a bed area of the press machine. Consequently, it may happen that additional press devices need to be provided to perform additional steps for the processing.

A wear plate 124 that is provided at a tip of the flange 121 extruding laterally from the main body portion 107a of the passive cam 107 is gradually worn by the repetitive sliding movements of the passive cam 107 so that a clearance may be created between the wear plate 124 and the lateral guide plate 122. As a result, the passive cam 107 may not be able to slide in a linear manner and may meander owing to the existence of the clearance. Since the punch 106 attached to the passive cam 107 will simultaneously meander, the punch 106 may not be able to perform punching in a preferable condition in which an appropriate clearance is formed over the whole circumference with respect to the die 125 so that burrs are formed along the circumference of the punched hole and boring processes of high quality could not be achieved. Additionally, since the punch 106 and die 125 performed punching causing burrs, there were also caused chipping of cutting edges of the punch 106 or the die 125.

In order to solve the above-discussed problems, it has been proposed for a press device as shown in Figs. 11, 12 and 13, patented as Japanese Patent No. 1975542 and U.S.P. No. 5,101,705. This press device is comprised of a sliding cam base 213 provided at an upper die 211 and which tip portion is provided with a tetrahedron guide portion 216, a sliding cam 217 which embraces the tetrahedron guide portion 216 of the sliding cam base 213, which makes the tetrahedron guide portion 216 slide, and to which processing members such as punch 243 or trimming cutting edge 251 are attached, an elastic member 264 interposed between the sliding cam base 213 and the sliding cam 217 for energizing the sliding cam 217, an operating cam abutting against the sliding cam 217 and provided at a lower die 202 for driving the sliding cam 217, and a positioning member 204 provided on the upper die 211 for supporting a work W for which presswork is to be performed using the processing members. With this device, it has been enabled to provide a press device comprised with a cam member wherein the cam member is capable of performing required functions, wherein a compact design is achieved, and high quality processing is enabled by preventing meandering of the cam member.

When the upper die 211 is descended in this press device, the sliding cam 217 moves in a lateral direction between the operating cam 208 and the sliding cam base 213 for performing presswork such as boring or trimming. When the upper die 211 is lifted after completion of processing, the sliding cam 217 is returned, being energized by the elastic member 264.

As shown in Fig. 12, an upper end of the sliding cam 217 is formed on a same inclined plane as the tetrahedron guide portion 216 of the sliding cam base 213 and is further formed with a groove for receiving the tetrahedron guide portion 216, a wear plate 223 is fixed by means of a bolt 224 for supporting a lower plane 225 of the tetrahedron guide portion 216 of the sliding cam base 213, an upper plane 226 thereof being pressed by a tapping plate 228 attached to the sliding cam 217 by means of a bolt 227, and the sliding cam 217 is provided in a freely slidable manner at the tetrahedron guide portion 216 of the sliding cam base 213.

As shown in Fig. 13, for forcibly retracting the sliding cam 217 accompanying the lifting movement of the upper die 211, a returning plate 271 is fixedly attached to the sliding cam 217 by means of a bolt 272, while a lower end thereof is engaged to the operating cam 8.

The above explained press device as shown in Figs. 11, 12 and 13 (patented as Japanese Patent No. 1975542 and U.S.P. No. 5,101,705) is an improvement of a conventional press device comprised with a cam member, while there are further points that need to be improved which will now be explained.

(1) Processing Accuracy

While it did not become critical in case the length in a width direction is short as shown in Fig. 12 (lateral directions in the drawing), in case the length in the width direction of the sliding cam 217 exceeds, for instance, a length of approximately 300 mm, the tetrahedron guide portion 216 of the sliding cam base 213 could not be sufficiently supported by the wear plate 223 and the tapping plate 228 attached to the sliding cam 217 alone. Consequently, warp was remarkably caused so that no accurate presswork could be performed. Moreover, since it took too much time for processing the tetrahedron guide portion 216, wear plate 223 or the tapping plate 228, the whole pressing device became expensive.

Movements of the sliding cam 217 above the sliding cam base 213 proved to be inaccurate since the sliding cam 217 could not be guided in a satisfactory manner.

Further, in conventional press devices, especially those of large size, the sliding surface assumed a bearing of as much as approximately 150 kg/cm², causing heavy wear, while measures against wear were not sufficiently taken.

(2) Operability of Maintenance

In a conventional press device, it was required to detach the tapping plate 228 by unfastening numerous bolts 227 as shown in Fig. 12 for detaching the sliding cam 217 from the sliding cam base 213 at the time of performing maintenance so that it took quite a time for the maintenance.

Moreover, for detaching the sliding cam 217 from the operating cam 208, it was required to remove the bolt 272 of the returning plate 271 as shown in Fig. 13. However, though not shown in the drawings, the returning plate 271 being provided over both sides of the slide cam 217, the operating cam 208, detaching the same was time-consuming.

(3) Protection of the Sliding Surface

As it is evident from Figs. 11 and 12, the sliding surfaces of the sliding cam 217 and the sliding cam base 213 are exposed so that scraps or similar may enter therefrom.

(4) Application of the Sliding Cam

It is preferable that the sliding cam to which processing members such as the punch 243 or trimming cutting edge 251 are attached be also applicable for receiving various components such as springs thereat.

The present invention has been made in view of these facts, and it has been provided for a press device free of warps or rolling and capable of performing accurate processing, comprising a sliding cam base, a sliding cam that is guided by the sliding cam base and to which processing members such as a punch are attached, an energizing body provided between the sliding cam base and the sliding cam for energizing the sliding cam, and an operating cam abutted against the sliding cam for driving the sliding cam, wherein the press device is arranged in that the sliding cam is provided in a freely slidable manner between two guide posts of circular section suspended from the sliding cam base and separated from each other by a specified distance, and wherein one surface of the sliding cam base is formed as a V-shaped groove and a surface of the sliding cam opposing this surface of the sliding cam base is formed, at the operating cam thereof, with an angular guide portion abutting the V-shape groove.

More particularly, the press device is arranged in that vertical surfaces are formed at both end portions of the V-shaped groove of the one surface of the sliding cam, in that vertical surfaces are formed at both end portions of the angular guide portion of the operating cam, and in that the wear plate of the V-shaped groove of the sliding cam and the wear plate of the angular guide portion of the operating cam as well as the wear plate of the vertical surfaces of the sliding cam and the wear plate of the vertical surfaces of the operating cam are respectively abutted against each other.

The present invention has further provided a press device wherein for ease of detaching the sliding cam from the sliding cam base, attaching/detaching of the two guide posts suspended from two supporting plates fixedly attached to the sliding cam base and an energizing body is enabled from a side of one of the supporting plates.

Moreover, the press device according to the present invention is arranged in that the sliding surfaces of the sliding cam and the sliding cam base is covered by the sliding cam base, sliding cam, the guide posts and the supporting plates on both sides from which the energizing body is suspended for preventing entry of scraps or the like.

Further, the present invention has provided for a press device wherein the sliding cam is applicable as a space to which components such as stripper guide, stopper bolt or coil spring may be attached for applying the sliding cam to receive various components.

BRIEF EXPLANATIONS OF THE DRAWINGS

Fig. 1 is a longitudinal sectional view at a bottom dead center of a press device according to one concrete embodiment of the present invention.

Fig. 2 is a view seen from a direction of arrow II of Fig. 1.

Fig. 3 is a view seen from a direction of arrow III of Fig. 1.

Fig. 4 is a view seen from a direction of arrow IV of Fig. 1.

Fig. 5 is a longitudinal sectional view at a top dead center of a press device according to one concrete embodiment of the present invention.

Fig. 6 is a longitudinal sectional view of a press device according to another example in which a sliding cam base is arranged at a lower die.

Fig. 7 is a view seen from a direction of arrow VII of Fig. 6.

Fig. 8 is a view seen from a direction of arrow VIII of Fig. 6.

Fig. 9 is a longitudinal sectional view of a conventional press device.

Fig. 10 is a longitudinal sectional view of a passive cam and its guide portion of Fig. 7.

Fig. 11 is a longitudinal sectional view at a bottom dead center of the conventional press device.

Fig. 12 is a sectional view seen from a direction of arrow XII-XII of Fig. 9.

Fig. 13 is a sectional view seen from a direction of arrow XIII-XIII of Fig. 9.

EMBODIMENTS

The present invention will now be explained in details based on concrete embodiments thereof as shown in the accompanying drawings.

Fig. 1 shows a press device according to one concrete embodiment of the present invention, which is a longitudinal sectional view at a bottom dead center thereof, Fig. 2 a view seen from a direction of arrow II of Fig. 1, Fig. 3 a view seen from a direction of arrow III of Fig. 1, Fig. 4 a view seen from a direction of arrow IV of Fig. 1, and Fig. 5 is a longitudinal sectional view at a top dead center thereof. Figs. 6 to 8 are respectively a longitudinal sectional view of a press device wherein a sliding cam is arranged at a lower die. It should be noted that in case of providing the sliding cam at an upper die, delivery of a work is made easier since the sliding cam will not be positioned at the lower die at the time of delivering the work.

In this embodiment, it will be explained for an example in which boring of a work is performed.

As shown in Fig. 1, a supporting member 3 for positioning work W is fixed on a lower substrate 2 of lower die 1 through bolt 4.

An operating cam 5 which upper surface is declined in approaching the supporting member 3 (that is, inclining rightward in the drawing) is fixed to the lower substrate 2 through bolt 6 in a proximity of the supporting member 3. This operating cam 5 is further formed in that its inclined surface 7 is as an angular guide portion 8 as shown in Fig. 2.

Further, as shown in Fig. 2, a wear plate 27 is fixed to the angular guide portion 8 through bolt 28, and an other wear plate 9 is fixed through bolt 10 to both vertical surfaces 15 of the operating cam 5 extending over both end portions of the angular guide portion 8.

As also shown in Fig. 2, the sliding cam 14, which overall schematic shape is wedge-shaped, and which lower surface is provided with a V-shaped groove 11, wherein a wear plate 12 is attached to the V-shaped groove 11 through bolt 13 and a wear plate 29 is attached to both vertical surfaces 53 extending to end portions of the V-shaped groove 11 through bolt 30, is mounted on the operating cam 5 in a freely slidable manner by respectively abutting the wear plate 12 of the V-shape groove 11 against the wear plate 27 of the operating cam 5 and the wear plate 29 against the wear plate 9 of the operating cam 5.

On the other hand, a sliding cam base 21 which is declined in a reverse direction as the operating cam 5, that is, declined rightward in the drawing, is fixed to an upper substrate 23 of an upper die 22 through bolt 24, and the above-described sliding cam 14 is provided in a freely slidable manner between two guide posts 25 suspended from lower end portions of the sliding cam base 21 in a rightward declining manner and separated from each other by a specified distance (reference should be made to Figs. 1, 3 and 4). The sliding cam 14 is energized by a gas spring 26 that is incorporated within the sliding cam base 21 and arranged in a rightward declining manner. It should be noted that the position of the gas spring 26 in Fig. 1 is schematically shown as being positioned upward for ease of understanding.

The guide posts 25 are suspended from supporting

plates

33, 34 that are respectively fixed to both sides of the sliding cam base 21 through

bolts

31, 32 as shown in Fig. 1. The guide posts 25 are fitted to

bushes

37, 38 that are fixed, in a coaxial manner through pressurizing, into piercing holes 36 of a guide post holding portion 35 located above the sliding cam 14. A small diameter portion 39 at one of the guide posts 25 is threaded in order to be screwed to a screw hole 40 of the supporting plate 33, and an other end portion 41 is fitted to a fitting hole 42 of the supporting plate 34. An end portion of the other end portion 41 of the guide post 25 is provided with an engaging hole 43 such as a hexagonal hole for detaching purposes.

Generally, circular outer peripheral surfaces or circular holes may be mechanically processed more accurately than compared to those of square or other shapes. For this reason, the guide posts 25 are made to assume a circular section and the

bushes

37, 38 as well as fitting hole 42 to be a circular hole in the present invention so that mechanical processing can be accurately performed. The relationship of fitting between the guide posts 25 which outer peripheral surfaces are circular and the

bushes

37, 38 which are circular holes makes it possible to maintain a fitting condition of high accuracy over the whole periphery of 360° with respect to the central axis.

While the guide posts may be either filled or hollow as long as they assume a circular section, it is preferable that these be filled in terms of strength.

For performing maintenance of the sliding cam 14, operating cam 5, or sliding cam base 21, it may be necessary to detach the sliding cam 14 from the sliding cam base 21. At this time, the sliding cam 14 may be separated from the sliding cam base 21 by performing the following steps for enabling easy operations of maintenance without the necessity of unfastening numerous bolts 227 as is the case with conventional devices: a detaching tool such as a L-shaped rod member having a hexagonal section is fitted to the engaging hole 43 of the two guide posts 25 on the side of the supporting plate 34 and also fitted into the engaging hole 44 via piercing hole 82 of the supporting plate 34 of the gas spring 26 and the L-shaped rod member is rotated, and thereafter, the guide posts 25 and gas spring 26 may be easily pulled out.

There are respectively provided a guide groove 45 assuming a V-shaped groove section in a rightward declining manner on a lower surface of the sliding cam base 21, and the guide post holding portion 35 is an extruding manner having an angular section in a rightward declining manner on an upper surface of the sliding cam 14, wherein the angular upper surface of the guide post holding portion 35 and the guide groove 45 are provided to be slidable. A wear plate 46 is fixed to the angular upper surface of the guide post holding portion 35 through bolt 47, and a wear plate 48 to the guide groove 45 through bolt 49, wherein the wear plate 46 and wear plate 48 are abutted against each other for sliding. At both ends of the guide post holding portion 35 there are formed piercing holes 36 in a rightward declining manner into which the

bushes

37, 38 are fitted through pressurizing in a coaxial manner so that the guide posts 25 are inwardly fitted into the

bushes

37, 38. The supporting plate 34 is provided as to cover guide groove 45 and the post holding portion 35 and is fastened through bolt 32.

As it is evident from Figs. 3 and 4, the sliding surfaces of the sliding cam 14 and the sliding cam base 21 form gently inclined surfaces forming a substantially reversed V-shape, and guide posts 25 are provided in a somewhat lower portion of both outer sides of the inclined surfaces. With this arrangement, the sliding cam 14 is capable of performing stable movements to achieve presswork of high accuracy.

The gas spring 26 that is disposed in a rightward declining manner is energized with its tip being abutted against an inner surface of the supporting plate 33, and by screwing a plug 81 provided with a thread 50 on the outer periphery thereof to the guide holding portion 35, the gas spring 26 is interposed between the plug 81 and the supporting plate 33. An end surface of the plug 81 is provided with a fitting hole 44 that is, for instance, a hexagonal hole provided for detaching purposes. A telescopic rod 52 at the tip of a cylinder 51 of the gas spring 26 abuts against an inner surface of the supporting plate 33 and a base end of the cylinder 51 abuts against the plug 81. The overall appearance of the sliding cam 14 assumes a shape of a wedge that is pressurized being pinched between the operating cam 5 and the sliding cam base 21 to move towards the work W placed on the supporting member 3 for processing the work W. Fig. 1 shows a condition at the bottom dead center. The sliding cam 14 is positioned to be closest to the supporting member 3, that is, leftward to the utmost in the drawing, and the rod 52 of the gas spring 26 is in a most shrunk condition. In the absence of a binding force acting on the sliding cam 14 through the operating cam 5 and the sliding cam base 21, energizing force of the gas spring 26 acts upon the sliding cam 14 so that its rod 52 starts to expand. The position of the top dead center is shown in Fig. 5 wherein the rod 52 is in a most expanded condition.

The gas spring 26 accumulates within the cylinder 51 thereof high pressure gas of, for instance, 150 kg/cm², depending on the purpose, and a substantially constant output of, for instance, 150 kg/cm², can be achieved over the whole length of the expanding process of the rod even though the rod 52 extending from the cylinder 51 is expanded or shrunk. In case the rod 52 is shrunk and pressure is applied to either one of two tanks incorporated within the cylinder 51, high pressure gas is flown out from the one tank into the other tank to achieve such a constant output.

The sliding cam 14 can be reliably returned to ensure safety by using the gas spring 26 with which it is possible to achieve high pressure output from the beginning and over the whole process as opposed to cases using an elastic body (coil spring) 264.

Using the gas spring 26 further enables it to make the sliding cam 14 travel a long distance of approximately 150 mm, and it is enabled to perform processing of large sized works such as thin plate formed articles for automobiles, e.g. side panels.

There are respectively provided

wear plates

48, 46 on the sliding surfaces of the sliding cam base 21 and the sliding cam 14. The wear plate 48 is fixed to the sliding cam base 21 through bolt 49, and the wear plate 46 to the sliding cam 14 through bolt 47. Since the sliding surfaces of the wear plate 46 and the wear plate 48 are covered by the sliding cam base 21, sliding cam 14 and the supporting

plates

33, 34, the sliding surfaces are protected by preventing entry of scraps. The sliding cam 14 may be applied as a space for attaching components such as a stripper guide, stripper bolt or coil spring thereat.

Conventionally, a press device comprised with a sliding cam of this sort had been provided with a wear plate only on either of the sliding cam base or sliding cam at a bearing of approximately 50 to 60 kg/cm², while the large sized press device according to the present invention is provided with wear plates on both the sliding cam base and the sliding base to be applicable to a bearing of approximately 150 kg/cm², wherein the wear plates are replaceable in case they are worn.

As already explained, the sliding cam 14 is guided by the two guide posts 25 that are suspended from the sliding cam base 21 disposed separately with respect to each other by a specified distance, whereby the sliding cam 14 can precisely move straight ahead on the sliding cam base 21. Further, since the sliding cam 14 is held by the two guide posts 25 disposed separately with respect to each other by a specified distance, rolling of the sliding cam 14 can be prevented to ensure exact press processing unlike cases in which it is held by only a single guide post 25. Moreover, since the sliding cam 14 is suspended by two guide posts 25 which are filled and which are of a relatively large diameter, the guide posts 25 also serve as safety pins which prevent the sliding cam 14 from dropping. Additionally, while the returning plate 271 had been used for forcing the sliding cam 217 to retract accompanying the lifting movement of the upper die 211 in a conventional device as shown in Fig. 11, the sliding cam 14 can be completely returned by employing the guide posts 25 and the gas spring 26 whereby the returning plate 271 can be omitted.

In order to achieve exact movements of the sliding cam 14 above the operating cam 5, the wear plate 12 of the V-shaped groove 11 of the sliding cam 14 is abutted against the wear plate 27 of the angular guide portion 8 and the wear plate 29 of the vertical surface 53 of the sliding cam 14 against the wear plate 9 of the vertical surface 15 of the operating cam 5 for making the sliding cam 14 slide without rolling, as shown in Fig. 2. The sliding between the sliding cam 14 and the operating cam 5 is performed through not only by the sliding movement between the V-shaped groove 11 and the angular guide portion 8 but also between the sliding movement between the vertical surface 53 of the sliding cam 14 and the vertical surface 15 of the operating cam 5, whereby pressure from lateral directions can be received to maintain straight ahead movements of the sliding cam 14. The assembly of the sliding cam 14 and the operating cam 5 can be easily performed by the provision of the

vertical surfaces

53, 15 of the sliding cam 14 and the operating cam 5 with the vertical surfaces functioning as a guide.

As shown in Fig. 1, a spacer 61 is fixed to the front surface of the sliding cam 14 through bolt 62 at a position opposing the supporting member 3 for the work W of the sliding cam 14. A punch 63 for boring the work W is supported by a punch plate 64 in an erected manner, and this punch plate 64 is fixed by bolt 65. A tip portion of the punch 63 is inwardly fitted to a stripper plate 66 while this stripper plate 66 is energized by a pressurizing rubber 67. The stripper plate 66 is suspended by a suspending bolt 68. On the other hand, a die bush 69 is embedded at a position opposing the punch 63 of the supporting member 63.

A condition of the press device at the top dead center is shown in Fig. 5.

Operations of this press device will now be explained.

As shown in Fig. 5, the work W is placed onto the supporting member 3 and the upper die 22 is descended. The condition as shown in Fig. 5 is a condition at the top dead center, wherein the sliding cam 14 is provided to be freely slidable at the guide posts 25 of the sliding cam base 21 attached to the upper substrate 21 of the upper die 22, and wherein the sliding cam 14 is in a condition in which it is abutted against the supporting plate 34.

When the upper die 22 is descended from this condition, the

wear plates

12, 29 of the sliding cam 14 are abutted against the

wear plates

27, 9 of the operating cam 5, and the sliding cam 14 moves towards the work W accompanying the descending of the upper die 22 between the operating cam 5 and sliding cam base 21 so that boring of the work W is performed by the punch 63 and the die bush 69.

A condition of the bottom dead center is shown in Fig. 1 in which boring with the punch 63 is performed.

Thereafter, when the upper die 22 is lifted, the energizing force of the gas spring 26 is transmitted from the plug 81 to the sliding cam 14 as to make the sliding cam 14 retract until it is abutted against the supporting plate 34 and is stopped thereat.

While the present embodiment has been explained based on a case in which boring is performed, the present invention is also applicable to other types of processing such as trimming, molding or bending.

Standardizing sizes of the sliding cam base 21, sliding cam 14 and the operating cam 5, the device may be immediately employed for processing works of a variety of sizes.

In the above explanations, the sliding cam base 21 is provided on the upper die 22 and the operating cam 5 on the lower die 1. However, similar effects can be achieved also in case the sliding cam base 21 and the sliding cam 14 are provided on the lower die 1 and the operating cam 5 on the upper die 22, as shown in Figs. 6 to 8. It should be noted that portions that are identical with those of the above-described embodiment are marked with the same reference numerals. Here, a wear plate 71 is fixed to the sliding cam 14 through bolt 72 and a wear plate 73 on the opposing operating cam 5 through bolt 74. Further, the sliding cam 14 is not suspended from the upper die 21 in this example but is provided on the lower die 1 so that it may be considered to provide safety of operation.

The present invention does not only cover a case in which the sliding cam 14 is provided on the upper die 22 but also a case in which the sliding cam 14 is provided on the lower die 1.

As explained so far, the press device according to the present invention comprises a sliding cam base, a sliding cam that is guided by the sliding cam base and to which processing members such as a punch are attached, an energizing body provided between the sliding cam base and the sliding cam for energizing the sliding cam, and an operating cam abutted against the sliding cam for driving the sliding cam, wherein the press device is arranged in that the sliding cam is provided in a freely slidable manner between two guide posts of circular section suspended from the sliding cam base and separated from each other by a specified distance, and wherein one surface of the sliding cam base is formed as a V-shaped groove and a surface of the sliding cam opposing this surface of the sliding cam base is formed, at the operating cam thereof, with an angular guide portion abutting the V-shape groove. With this arrangement, warps or rolling can be eliminated and accurate processing can be performed.

Further, the press device according to the present invention is arranged in that vertical surfaces are formed at both end portions of the V-shaped groove of the one surface of the sliding cam, in that vertical surfaces are formed at both end portions of the angular guide portion of the operating cam, and in that the wear plate of the V-shaped groove of the sliding cam and the wear plate of the angular guide portion of the operating cam as well as the wear plate of the vertical surfaces of the sliding cam and the wear plate of the vertical surfaces of the operating cam are respectively abutted against each other. With this arrangement, accurate processing can be reliably performed.Moreover, the press device according to the present invention is arranged in that attaching/detachi ng of the two guide posts suspended from two supporting plates fixedly attached to the sliding cam base and an energizing body is enabled from a side of one of the supporting plates. With this arrangement, detaching the sliding cam from the sliding cam base is made easy and maintenance operations can be made easy.

Additionally, the press device according to the present invention is arranged in that the sliding surface of the sliding cam and the sliding cam base is covered by the sliding cam base, the sliding cam, the guide posts and the supporting plates on both sides from which the energizing body is suspended. With this arrangement, entry of scraps or the like can be prevented.

Further, the press device according to the present invention is arranged in that the sliding cam is applicable as a space to which components such as stripper guide, stopper bolt or coil spring may be attached. With this arrangement, various components can be attached to the sliding cam.

Claims

A press device comprising a sliding cam base, a sliding cam that is guided by the sliding cam base and to which processing members such as a punch are attached, an energizing body provided between the sliding cam base and the sliding cam for energizing the sliding cam, and an operating cam abutted against the sliding cam for driving the sliding cam, wherein the press device is arranged in that the sliding cam is provided in a freely slidable manner between two guide posts of circular section suspended from the sliding cam base and separated from each other by a specified distance, and wherein one surface of the sliding cam base is formed as a V-shaped groove and a surface of the sliding cam opposing this surface of the sliding cam base is formed, at the operating cam thereof, with an angular guide portion abutting the V-shape groove.
The press device as claimed in Claim 1, wherein vertical surfaces are formed at both end portions of the V-shaped groove of the one surface of the sliding cam, wherein vertical surfaces are formed at both end portions of the angular guide portion of the operating cam, and wherein the wear plate of the V-shaped groove of the sliding cam and the wear plate of the angular guide portion of the operating cam as well as the wear plate of the vertical surfaces of the sliding cam and the wear plate of the vertical surfaces of the operating cam are respectively abutted against each other.
The press device as claimed in Claim 1, arranged in that attaching/detaching of the two guide posts suspended from two supporting plates fixedly attached to the sliding cam base and an energizing body is enabled from a side of one of the supporting plates.
The press device as claimed in Claim 1, arranged in that the sliding surfaces of the sliding cam and the sliding cam base are covered by the sliding cam base, the sliding cam, the guide posts and the supporting plates on both sides from which the energizing body is suspended.
The press device as claimed in Claim 1, arranged in that the sliding cam is applicable as a space to which components such as stripper guide, stopper bolt or coil spring may be attached.