US3530749A - Parallel-motion control mechanism - Google Patents

Parallel-motion control mechanism Download PDF

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Publication number
US3530749A
US3530749A US722442A US3530749DA US3530749A US 3530749 A US3530749 A US 3530749A US 722442 A US722442 A US 722442A US 3530749D A US3530749D A US 3530749DA US 3530749 A US3530749 A US 3530749A
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Prior art keywords
ports
control
passage
cylinder
valve
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Expired - Lifetime
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US722442A
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English (en)
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Hans Rohmer
Bozidar Habazin
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/22—Synchronisation of the movement of two or more servomotors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
    • B30B15/16—Control arrangements for fluid-driven presses
    • B30B15/24—Control arrangements for fluid-driven presses controlling the movement of a plurality of actuating members to maintain parallel movement of the platen or press beam
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T83/00—Cutting
    • Y10T83/141—With means to monitor and control operation [e.g., self-regulating means]
    • Y10T83/148—Including means to correct the sensed operation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T83/00—Cutting
    • Y10T83/869—Means to drive or to guide tool
    • Y10T83/8696—Means to change datum plane of tool or tool presser stroke
    • Y10T83/8699—With adjustable stop
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T83/00—Cutting
    • Y10T83/869—Means to drive or to guide tool
    • Y10T83/8696—Means to change datum plane of tool or tool presser stroke
    • Y10T83/87—By varying length of tool stroke
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T83/00—Cutting
    • Y10T83/869—Means to drive or to guide tool
    • Y10T83/8821—With simple rectilinear reciprocating motion only
    • Y10T83/8837—With application of force to opposite ends of tool supporting crosshead
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T83/00—Cutting
    • Y10T83/869—Means to drive or to guide tool
    • Y10T83/8821—With simple rectilinear reciprocating motion only
    • Y10T83/8858—Fluid pressure actuated

Definitions

  • ABSTRACT Parallel-motion control mechanism for doubleacting ram cylinders, particularly in trimming presses and the like machine tools, wherein a single valve is interposed between the pressure-fluid feed pipes and the pressure ducts to the individual cylinders, with a single piston, and having rotatable control disks at the ends of the valve body, the disks having ports which provide communication between a number of ducts so as to provide efficient compensation for asymmetrical loads.
  • the invention relates to a parallel-motion control mechanism for two or more, preferably double-acting, hydraulically actuated ram cylinders, in particular for operating edging or trimming presses and similar machine tools.
  • One known form of embodiment relates to a hydraulic press with a plurality of cylinders having pistons which are coupled with a common press plunger, the skewing whereof, when the synchronization of the action of these pistons is disturbed, produces a variation in the quantity of power fluid supplied to these cylinders, counteracting the aforesaid skewing effect.
  • each such control element is associated with a fixed stop limiting the displacement of said valve element in the opening direction.
  • the action of the transmitting means altering the setting of said hydraulic control means is first required to override the restoring force of a spring which must be sufficiently high to act also as a holding force.
  • the delivery of a pump coupled with each press cylinder is controlled in accordance with the amount of skewing of the press plunger. It is further known to vary the quantity of the power fluid admitted to the cylinder to counteract errors in parallelism by opening or closing the admission ducts for the power fluid connecting the individual cylinders with the power fluid supply.
  • a common control valve can be provided, controlling a plurality of such ducts opening into each cylinder or a number of control valves or flaps associated with each cylinder.
  • the object of the present invention is consequently to eliminate the aforesaid disadvantages and provide an absolutely accurate synchronizing mechanism ensuring complete parallelism.
  • I I I I According to one of the major features of the invention, this is effected in such a manner that a single valve is interposed between the pressure fluid feed pipes and the pressure ducts to the individual cylinders, with a single hydraulically actuated piston, and having at the ends of the valve body, looking in the direction of motion of said piston, rotatable control disks with notches or ports for communication between corresponding ducts or passages.
  • valve piston is provided with a shaft or spindle which carries gear wheels associated with a press ram or plunger of the machine tool, the control mechanism having in the middle thereof a further gear wheel meshing with a resiliently biased rack bar.
  • FIG. 1 illustrates in a somewhat schematic sectional view a synchronizing valve forming part of the inventive control mechanism
  • FIG. 2 is a partly structural and partly schematic illustration of the synchronizing controls of the invention
  • FIG. 3 is a transversal sectional view of the valve mechanism, taken along line III-III in FIG. 1;
  • FIG. 4 is an end view ofone of the control disks, taken along line IV-IV ofFIG. 1;
  • FIG. 5 is another sectional view of the valve mechanism, taken along line V-V in FIG. 1; 7
  • FIG. 6 is an end view of the other control disk, taken along line VI-VI in FIG. 1;
  • FIG. 7 is a side view of one of the spindle mechanisms with the corresponding rack bar, used in the inventive control mechanism.
  • FIG. 8 shows a further rack bar as arranged between the two spindles, as shown in FIG. 7.
  • a pump 1 delivers pressure fluid through a pipe or passage 2 to a valve 3, further flow being interrupted to other connections in the valve by way of passages 4 and 5.
  • the fluid feed is directed without pressure through a valve 6 to a discharge 7.
  • the upper chamber or space of a press cylinder 9 is connected by way of a pipe 78 with a passage 8 in the valve 3, and the upper chamber of a second press cylinder 11 is similarly connected by way of a pipe 79 with a passage 10 in the valve.
  • cylinder 9 is the left-hand element and cylinder 11 the righthand element of the inventive control system, as will be explained in more detail as the specification proceeds.
  • the lower side of cylinder 9 is connected with a passage 12 and the lower side of cylinder 11 with a passage 15 in the valve 3, both by way of a pipe 76 as shown.
  • the valve 3 contains a piston 16 which in the rest position is held at both ends by springs 17 at the middle of its stroke. This closes the connection between the cylinders 9, 11 and the pump 1 as well as the discharge 7 by way of the respective narrower and wider piston sections, as shown in FIG. I.
  • the piston 16 has the further purpose of connecting the pump 1 with either cylinder 9, 1 1 through the appropriate passages, or with a discharge pipe or return circuit 82.
  • control disks l8 and 19 (FIGS. 4 and 6, respectively) associated with the working or power cylinders.
  • These control disks are housed in respective covers 20 and 21 and easily rotatable in either direction until they leave axially a minimum amount of play between a casing or valve body 22 and the respective cover.
  • Both end faces of the body 22 have control apertures in a particular arrangement with respect to each other, as will be seen from FIGS. 3 and 5.
  • Ports 24a, 24b are connected with a passage 25 while ports 26a, 26b communicate with a passage 27.
  • Ports 28a, 28b are in communication with a passage 29.
  • the ports 24a, 24b are radially extended by slits 30a, 30b.
  • the ports 28a, 28b are similarly extended by slits 31a, 31b.
  • Ports 14a, 14b in the body 22 are connected with a port 13 of valve 3, while ports 32a, 32b, also in the body 22, shown in FIGS. 3 and 5, respectively, with the passage 5, similarly in the body 22, ports 33a, 33b with a passage 34, ports 35a, 35b with a passage 36, bores 37a, 37b with a passage 38, and ports 39a, 39b with a passage 40.
  • the ports 33a, 33b are continued in the direction of the pitch circle by slits 41a, 41b.
  • the ports 37a, 37b are also extended in the direction of the pitch circle by slits 42a, 42b.
  • both disks have on their end faces depressions or hollows arranged in a predetermined and particular manner.
  • control disks 13, 19 on the side of the end faces of the body 22 afford communication between the individual control ports on said body 22, i.e., open or close them as may be necessary for correcting alignment errors in the parallel motion.
  • the control disks are completely pressure balanced. They are connected by respective spindle portions 43 and 44 (FIG. 2) with corresponding gear wheels 45 and 46. These wheels mesh with corresponding rack bars 47 and 48, coupled by respective rods 49 with rack bars 50 and 51.
  • a press ram or plunger 52 (FIG. 2) carries a through shaft or spindle 53 in three bearings, the shaft being provided with gear wheels 54, 55 and 56.
  • the rack bars 50, 51 mesh with the gear wheels 54, 55 as long as the wheel 56 is in mesh with a rack bar 57.
  • the rack bars 50, 51 are freely suspended but held together by respective bearing rollers 58 and 59.
  • the rack bar 57 is upwardly biased by a spring 60 (see FIG. 8) and is slidable only in the direction of the pressure or power stroke of the press plunger 52. This locking of the rack bar 57 also holds the rack bars 50, 51.
  • Valves 71, one each for the cylin ders7 and 9 are only schematically represented in FIG. 2, and serve as arresting valves during the downstroke of the press plunger 52 (see FIG. 2) until they give free passage in the opposite direction to the lower spaces of respective cylinders 9, l 1.
  • valve 6 When the valve 6 (see FIG. 2) is set for a press stroke, it interrupts the pressure free flow from the pump 1 to an intermediate section of a pipe or passage 61 and thence into the return pipe or discharge 7. In this manner, the pump 1 is placed in communication with a pipe or passage 62, and the pipe 2, while a pipe or passage is now connected with the discharge 7. Consequently, pressure is admitted by way of passage 62 to a chamber 64 in the valve 3 (see FIG. 1) while a chamber 63 therein is connected with the discharge pipe 7 by way of passage 65.
  • the piston 16 necessarily moves to the left, by the pressure applied in the chamber 64, and stops at the end of its stroke.
  • the delivery from the pump 1 passes through pipe 2 and thence through a passage 66 and ports 67 and 68, respectively, to the control disks 18, 19 (FIG. 1). It the error in parallelism between the press ram 52 and a platen 52' equals zero, and the rack bars 50, 51 are not moved, the spindle portions 43, 44, and with them the control disks l8, 19 remain in mid-position.
  • the control disk 18 is also shown in FIG. 4.
  • the hollows or ports are located on both sides of the end face of the control disk, those on the one side being for regulating and those on the other side only for compensating the pressure. All the hollows are connected by bores 69, as represented in FIG. 4 (and also in FIG. 6, for disk 19).
  • the control disk is considered to be in the zero or neutral position when the respective passage cross sections 70a, 70b, 72a, 72b from the ports 23a, 23b to the control disk 18 are of identical area.
  • the oil or hydraulic fluid passes through the passage 66 and the port 67 in the control disk 18, to the ports 26a, 26b and 28a, 28b, respectively.
  • the ports 26a, 26b lead to the passage 27 and through the free opening thereof, the pressure fluid reaches the passage 8 and the upper chamber of cylinder 9, respectively.
  • the ports 28a, 28b lead into the passage 29 wherein the further flow to the other passages is blocked.
  • the oil passes through the control disk 19 and into the ports 35a, 35b or the passage 36, respectively, and further into the upper chamber of cylinder 11.
  • the lower side of cylinder 9 (FIG. 1) is placed in communication by the valve 71 with one of the passages 12 and 13, respectively.
  • the passage 13 leads to the ports 14a, 14b and through the control disk 18 to the ports 24a, 24b. The latter lead into the passage 25.
  • This passage is connected with the previously mentioned discharge pipe or passage 82.
  • the lower space of cylinder 11 is similarly connected, through the other valve 71, with the passage 15, or with the passage 40, respectively.
  • the latter communicates with the ports 39a, 39b.
  • These ports are connected through the control disk 18 with the ports 33a, 33b, and the latter communicate with the passage 34 which is in communication with the discharge pipe 82.
  • the gear wheel 56 meshes with the rack bar 57, and the gears 54, 55 similarly mesh with the rack bars 50, 51. Since the rack bar 57 is pretensioned upwards by the spring 60, the rack bars 50, 51 are now immobilized. If the left-hand cylinder 9 leads with reference to the right hand cylinder 11, that is, when the press beam or plunger 52 becomes skewed, the rack bar 51 is drawn downwards; and since the gear 56 is in mesh with the rack 57, which is upwardly pretensioned, the opposite rack bar 51 is imparted an identical, oppositely directed motion.
  • the left-hand, leading side is drawn down by the vertical displacement of the rack bar, and the spindle 43 will rotate clockwise; similarly, the control disk 18 will be rotated by the action of the spindle 44 in the opposite direction. Since the left-hand side is continuously in the lead, the passage cross sections 72a, 72b, 73a, 73b will also be reduced, as well as the connections between the pump and the upper cylinder space, and between the lower cylinder space and the return circuit.
  • the ports 26a, 26b are placed in communication with the slits 30a, 30b through the hollows in the control disk 18. Since these slits are in communication with the ports 24a, 24b, and the latter communicate with the passage 25, a connection is established from the upper side of the cylinder 9 to the return circuit 82.
  • the pressure fluid flows through the pipe 65 into the chamber 63, and the chamber 64 is relieved of load by the pipe 62.
  • the piston 16 moves to the right, to the end of its stroke.
  • the pressure fluid passes through the ports 23a, 23b and the bores or cross sections 70a, 7b into the ports 28a, 28b.
  • These ports communicate with the passage 29 and thence with the passage 12 which in turn communicates through the pipe 76 and one of the valves 71 with the lower space of cylinder 9.
  • the upper space thereof is connected with the passage 8 and the latter with the passage 25 leading to the discharge pipe 82.
  • Another pipe 76 is provided for cylinder 11, as shown and explained before.
  • the ports 32a, 32b are connected by apertures 74a, 74b with the ports 37a, 37b and thence with the passage 38 continuing further into the passage 15. From the latter, through the pipe 76 and the other valve 71, the pressure fluid finally reaches the lower space of cylinder 11.
  • the upper space of the same communicates through the pipe 79 with the passage 10, and the latter with the passage 34, leading furtherinto the return pipe 82.
  • the ports 35a, 35b as well as the ports 39a, 39b lead into the respective passages 36, 40.
  • the further connections are closed.
  • the press plunger 52 moves upwardsf I If the right-hand side of the press plunger leads the left-hand side, the rack bar 51 is moved for the same distance upwards by the central bearing (gear wheel 56 with rack bar 57) while the rack bar necessarily moves downwards. Consequently, the rods 49 and the rack bar 48 meshing with the gear wheel 56, as well as the spindle 44, are rotated in clockwise sense.
  • the spindle 43 rotates through the same angle but in the opposite direction.
  • the rotation of the control disk 19 causes throttling of the cross sections or apertures 74a, 74b while similar rotation of the control disk causes the cross sections or bores 70a, 70b to be increased.
  • the cylinder 11 slows down its motion while the cylinder 9 correspondingly speeds up. This corrects the error in parallelism.
  • the length of stroke can be adjusted by a setting screw and a bearing nut 81, fitted on the press platen 52' associated with the press ram 52 (see FIG. 8). Accurate stopping is possible only in the pressing direction. This is attained in the following manner: The press plunger 52 moves downwards, and with it the setting screw 80. The rack bar 57 with the spring 60 are exactly in the mid-position. During the free stroke, the rack bar 57 remains stationary and the gear wheel 56 rotates therealong.
  • the setting screw 80 approaches the rack bar 57, overcoming the force of the spring 60.
  • the rack bar 57 is thus constrained to move with the same speed as the press plunger 52 through a corresponding distance downwards, and by this action of the rack bar and the meshing of the gear wheel 56 with the rack bar, the spindle 53 is similarly moved downwards, without rotation.
  • This causes the rack bars 50, 51 on the spindle 53 similarly to move downwards, and the rack bars 47, 48 rotate the respective spindle portions 43, 44.
  • the portion 43 is rotated clockwise and the portion 44 counterclockwise.
  • each control disk has a separate control valve, associated therewith in separate assemblies, each of which functioning through the corresponding piston or cylinder and control disks, to perform the combined function of the single valve as described herein.
  • valve system left and right, as viewed in FIGS. 1 and 2): 17, 49, 58,59, 66, 69, 71 and 76.
  • leftand right-side elements can be listed as follows: 4, 5; 8, 10; 9, ll; 12, 15; 13, 40; l8, 19; 20, 21; 25, 34; 27, 36; 29, 38; 43, 44; 45, 46; 47, 48; 50, 51; 54, 55; 63, 64; 65, 62; 67, 68; and 78, 79.
  • a parallel-motion control mechanism for at least two double-acting, hydraulically actuated cylinders, in particular for the operation of edging and trimming presses and the like machine tools, the latter having a press plunger 52; two press cylinders 9, 11 having respective power pistons operatively coupled with said plunger; means 43 to 57 for correcting errors in parallelism between said cylinders by the application of counter-pressure in the latter; said means including rack bars 47, 48, 50, 51 adjustable in the direction of motion of said pistons, and at least one pair of gear wheels 45, 46, 54, 55 meshing with said rack bars and arranged at the ends of at least one spindle 43, 44, 53 extending substantially over the entire length of said plunger and carried thereby, the improvement comprising, in combination, pressure pipes 76, 78, 79 leading to said cylinders; pressure-fluid feed lines 2, 7, 61, 62, 65, 82 associated with said pipes; and valve means 3 for controlling an actuating piston 16 therein, said pressure pipes coacting with
  • valve means 3 and said disks I8, 19 constitute independent control means performing substantially identical functions.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Engineering & Computer Science (AREA)
  • Control Of Presses (AREA)
  • Control Of Cutting Processes (AREA)
  • Press Drives And Press Lines (AREA)
US722442A 1967-04-18 1968-04-18 Parallel-motion control mechanism Expired - Lifetime US3530749A (en)

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Application Number Priority Date Filing Date Title
DER0045789 1967-04-18

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US722442A Expired - Lifetime US3530749A (en) 1967-04-18 1968-04-18 Parallel-motion control mechanism

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US (1) US3530749A (en:Method)
JP (1) JPS5030308B1 (en:Method)
AT (1) AT278476B (en:Method)
BE (1) BE713831A (en:Method)
CH (1) CH471976A (en:Method)
DE (1) DE1601751B1 (en:Method)
FR (1) FR1566860A (en:Method)
GB (1) GB1230165A (en:Method)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3854362A (en) * 1971-08-23 1974-12-17 Atom Cantella Deambrosis Hydraulic control system for hollow punching machines
US3935778A (en) * 1973-07-10 1976-02-03 Usm Corporation Apparatus for actuating a plurality of piston and cylinder assemblies
US4389874A (en) * 1980-03-21 1983-06-28 Officine Mecchaniche Mario Riboldi S.N.C. Di Renato, Carlo Riboldi & C. Bending brake
US5252053A (en) * 1991-02-26 1993-10-12 Boschman Technologies B.V. Apparatus for closing a mold
CN119036543A (zh) * 2024-09-12 2024-11-29 佛山市南台精机科技有限公司 一种用于模切机的误差修正方法及系统

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3854362A (en) * 1971-08-23 1974-12-17 Atom Cantella Deambrosis Hydraulic control system for hollow punching machines
US3935778A (en) * 1973-07-10 1976-02-03 Usm Corporation Apparatus for actuating a plurality of piston and cylinder assemblies
US4389874A (en) * 1980-03-21 1983-06-28 Officine Mecchaniche Mario Riboldi S.N.C. Di Renato, Carlo Riboldi & C. Bending brake
US5252053A (en) * 1991-02-26 1993-10-12 Boschman Technologies B.V. Apparatus for closing a mold
CN119036543A (zh) * 2024-09-12 2024-11-29 佛山市南台精机科技有限公司 一种用于模切机的误差修正方法及系统

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Publication number Publication date
GB1230165A (en:Method) 1971-04-28
CH471976A (de) 1969-04-30
DE1601751B1 (de) 1971-02-11
FR1566860A (en:Method) 1969-05-09
JPS5030308B1 (en:Method) 1975-09-30
AT278476B (de) 1970-02-10
BE713831A (en:Method) 1968-09-16

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