US2173358A - Press with work ejector - Google Patents
Press with work ejector Download PDFInfo
- Publication number
- US2173358A US2173358A US132574A US13257437A US2173358A US 2173358 A US2173358 A US 2173358A US 132574 A US132574 A US 132574A US 13257437 A US13257437 A US 13257437A US 2173358 A US2173358 A US 2173358A
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- press
- valve
- work
- platen
- cylinder
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B30—PRESSES
- B30B—PRESSES IN GENERAL
- B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
- B30B15/32—Discharging presses
Definitions
- This invention relates to presses, and in partlcular, to presses having means associated therewith for ejecting work-pieces therefrom.
- One object of this invention is to provide a 5 press having means associated therewith and responsive to the return stroke of the platen for ejecting the work-piece from the die of the press.
- Another object is to provide such a press, wherein a fluid-operated work-ejecting cylinder is controlled by a valve which, in turn, is actuated in response to the return stroke of the platen to eject the work-piece from the die.
- Another object is to provide a press having a fluid-operated work-ejecting cylinder associated with the platen or ram of the press, and controlled by a valve which is operated automatically in response to the completion of the pressing stroke of the press.
- Another object is to provide a press having a uld-operated work-ejectlng cylinder mounted upon the platen or ram of the press and controlled by a valve, which in turn, is shifted by its engagement with a membervmounted to permit relative movement between the valve and the member.
- Another object is to provide a press having a duid-operated work-ejecting cylinder mounted upon the platen or ram, together with a valve which is automatically shifted on the return stroke y of the platen to advance the ejecting plunger and 3o expel the work-piece, and on the forward stroke of the press is operated to retract the plunger so as to place it in readiness for expelling the next work-piece as soon as the next forward or pressing stroke is completed.
- Figure l is a diagrammatic view, in central vertical section, showingf the principal parts of a press having one embodiment of the work-expelling means of this invention associated therewith.
- Figure 2 is a central vertical section through the uid-operated work-ejecting cylinder associated with the press.
- Figure 3 is a bottom plan view of the workejecting cylinder shown in Figure 2.
- Figure 4 is a side elevation, partly in section, of
- Figure 5 is a bottom plan view of the press ram shown in Figure 4.
- the invention l consists of a press having a fluid-operated work-ejecting cylinder associated with the ram or platen thereof.
- the fluid for operating this cylinder is controlled by a valve, preferably a four-way valve, which is operated by means responsive tothe return stroke of the platen for electing the work-piece.
- Figure l I shows diagrammatically the principal elements of a press having the work ejector of this invention.
- the press consists of a frame top member I0 and a bed I having a working surface I2 for support- 5 ing suitable dies; or other apparatus used in connection with the press.
- the top member I0 and bed I I are ordinarily interconnected oy strain rods which are here dotted in order to bring out clearly the other elements of the press.
- a control 10 rod I3 also interconnects the top member I0 and the bed II, and is mounted in the bores I4 and I5 thereof.
- the stop or cam member I6 is mounted for adjustable movement along the control rod I3, and may be clamped in any desired position by tightening the screw Il.
- the cam member or stop I6 is provided with a cam edge or surface I8 for operating a valve, 'in a manner hereinafter described.
- the frame top member I0 is provided with a 20 cylinder I9 having a bore 20, within which a hollow ram 2
- a gland 22 and a packing 23 prevent leakage of fluid between the ram 2
- is provided'wlth a recessed head 24 and also with 25 an vinterior chamber 25 having an outlet bore 26 ( Figure 4) near the bottom thereof. This bore 26 widens into a larger outlet bore 2'I forming an annular surface 28 between the bore 2l. and the outer wall 23 of the ram 2l.
- recesses 30 spaced at intervals around the periphery of the ram 2
- the press platen 36 is provided with a hollow chamber 31 therein.
- a piston head 4I Secured to the opposite end of the plunger 40 is a piston head 4I which reciprocates in a cylinder bore 42 within the workl ejecting cylinder 33. The latter is provided with a bore 43 for the passage of the ejecting plunger 50 40, a packing 44 and retaining plate 45 vbeing providedv for preventing leakage around the. plunger 40.
- the plate 45 is secured in position by means of the cap screws 46.
- the bore 43 and thepacking 44 are mounted 55 '49 ( Figure 3).
- the cylinder head 41 is provided with a threaded port 50 for the reception of a pipe 5
- the cylinder head 41 is likewise provided with a bore 52 through which passes a, pipel 53, terminating within the threaded port '54 ( Figure 2) leading to the passageway 55 within the walls of the main portion 48 of the cylinder 33.
- the passageway 55 terminates in a threaded port 56 having the threaded connection 51, from which the pipe 58 passes to a threaded connection 59 secured within the threaded port 60 in the upper wall of the main cylinder portion 48.
- the pipe 53, passageway 55 and pipe 58 convey fluid to the space above the piston head 4I.
- the cylinder portion 48 is provided with a marginal flange 6I which fits within the outlet bore 21 of the plunger or ram 2
- and 53 pass throughthe hollow chamber 31 within the platen 36 by way of the opening 62 therein, and pass outwardly through an opening 63 in the top wall thereof to a valve 64.
- the latter is mounted upon a bracket 65 on the upper surface of the platen 36, and is provided with intake and exhaust lines 66 and 61, respectively. These lines 66 and 61 lead to any suitable source of pressure fluid, such as a pump, the distribu- ,tion of this fluid being effected by the valve 64.
- the valve 64 is preferably a four-way valve of conventional construction, and is operated by a valve lever 68 having a roller 69 mounted on the upper end thereof, and adapted to be operated by engagement with the cam surface I8 of the cam or stop I6 as the platen 36 and ram 2
- the press is started upon its forward stroke by admitting pressure fluid to the space above the main ram 2
- a surge valve system (not shown) is employed to permit theram 2
- the lever 68 of the valve 64 passes the cam I6 so that the roller 63 engages the cam surface I8 to move the valve lever 68 counterclockwise. 'I'his action admits pressure fluid into the space beneath the ejector piston head 4
- the platen 36 After the platen and the die or dies have completed the pressing stroke, the platen 36 begins its return stroke by the action of the usual return or push-back cylinders (not shown). As the valve 64 again passes the cam I6 on the return stroke of the platen 36, the roller 69 again engages the cam surface I8, swinging the valve lever 68 in a clockwise direction. This shifts the valve 64 to admit pressure uid into the space above the ejector piston head 4
- the 'I'he length of the cam surface VI8 determines the length of time during which pressure iiuid will be applied to the ejecting cylinder 33, after which the valve roller 68 slips off the cam'surface I8 and causes the valve lever 68 to return to its ,hollow plunger structure.
- the ejector plunger 48 After the platen returns to its top or retracted position, the ejector plunger 48 will, of course, be in its advanced or ejecting position, but will be again retracted when the valve 64 is again shifted by the engagement of the valve roller 63 with the cam surface I8 upon the next forward stroke of the platen 36.
- the four-way valve 64 form no part of the present invention as this valve is o1' any suitable conventional design. It is evident that in the operation of the four-way valve 64, when the pressure line 66 is connected through the valve 64 to one side of the ejector piston head 4
- the ejector plunger 40 and its piston head 4I may be operated by any suitable fluid, compressed air having been found convenient for this purpose. It will be obvious, moreover, that the application of this work-ejecting device is not conilnedv to fluid-operated presses, but may be employed equally well with mechanically-operated presses.
- a main cylinder a main plunger structure reciprocable relatively to said main cylinder and operated thereby, a double-acting work-ejecting cylinder and piston mounted on said plunger structure and movable therewith, a work ejector connected to said piston, an ejection control valve mounted on said structure and having a valve-operating member connected thereto, a stationary support mounted adjacent said plunger structure, and a valve-actuating cam adjustably mounted on said support and disposed in the path of travel of said valve-operating member, said valve-operating member being engageable with said cam to shift said valve at predetermined positions upon the forward and return strokes of said plunger structure to respectively retract andA advance said work ejector.
- amain cylinder a main plunger structure reciprocable relatively to said main cylinder and operated thereby, a double-acting work-ejecting cylinder and piston mounted on said plunger structure and movable therewith, a work ejector connected tov said piston,an ejection control valve mounted on said 'structure and having a valve-operating member connected thereto, a stationary support mounted adjacent said plunger structure, and a valveactuating cam adjustably mounted on said support and disposed in the path of travel of Laid valve-operating.
- saidvalve-operating member being engageable with said cam to shift said valve at predetermined positions upon the forward and return strokes of said plunger structure to respectively retract and advance said work ejector, said main plunger structure being hollow and said work-ejecting cylinder and piston being mounted in the interior of said WALTER ERNST.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Press Drives And Press Lines (AREA)
Description
Sept. 19, 1939.
W. ERNST PRESS WITH woRx EJEcToR Filed March 23, 1937 3 Sheets-Sheet 1 vl; 2. 57 j 5 Jwueador, `WALTER' ERNST, ,BY
W. ERNST PRESS WITH WORK EJECTOR Sept. 19, 1939.
3 Sheets-Sheet 2 Filed March 25, 1937 w ow v Mam 1 a n //////.1\Il ---w u H/ ,u
m G mv I m We im n .Nmzl .mw @w Y WALTER ERNST,
Sept. 19, 1939. w. lERNST PRESS WITH woRx maca-n Filed March 23, 1937 3 Sheets-Sheet 3 WWW-HW WA LTE R Patented Sept. 19, 1939 UNITED vSTATESv PRESS WITH WORK EJECTOB Walter Ernst, Mount Gilead, Ohio, .assignor to The Hydraulic Press Corporation, Inc., Wilmington, Del., a corporation of Delaware Application March 23, 11937, Serial No. 132,574
2 Claims.
This invention relates to presses, and in partlcular, to presses having means associated therewith for ejecting work-pieces therefrom.
One object of this invention is to provide a 5 press having means associated therewith and responsive to the return stroke of the platen for ejecting the work-piece from the die of the press.
Another object is to provide such a press, wherein a fluid-operated work-ejecting cylinder is controlled by a valve which, in turn, is actuated in response to the return stroke of the platen to eject the work-piece from the die.
Another object is to provide a press having a fluid-operated work-ejecting cylinder associated with the platen or ram of the press, and controlled by a valve which is operated automatically in response to the completion of the pressing stroke of the press.
Another object is to provide a press having a uld-operated work-ejectlng cylinder mounted upon the platen or ram of the press and controlled by a valve, which in turn, is shifted by its engagement with a membervmounted to permit relative movement between the valve and the member.
Another object is to provide a press having a duid-operated work-ejecting cylinder mounted upon the platen or ram, together with a valve which is automatically shifted on the return stroke y of the platen to advance the ejecting plunger and 3o expel the work-piece, and on the forward stroke of the press is operated to retract the plunger so as to place it in readiness for expelling the next work-piece as soon as the next forward or pressing stroke is completed. In the drawings:
Figure l is a diagrammatic view, in central vertical section, showingf the principal parts of a press having one embodiment of the work-expelling means of this invention associated therewith. Figure 2 is a central vertical section through the uid-operated work-ejecting cylinder associated with the press.
Figure 3 is a bottom plan view of the workejecting cylinder shown in Figure 2. Figure 4 is a side elevation, partly in section, of
the press ram shown in Figure 1.
Figure 5 is a bottom plan view of the press ram shown in Figure 4. j
In general, the invention lconsists of a press having a fluid-operated work-ejecting cylinder associated with the ram or platen thereof. The fluid for operating this cylinder is controlled by a valve, preferably a four-way valve, which is operated by means responsive tothe return stroke of the platen for electing the work-piece.
Referring to the drawings in detail, Figure l I shows diagrammatically the principal elements of a press having the work ejector of this invention. The press consists of a frame top member I0 and a bed I having a working surface I2 for support- 5 ing suitable dies; or other apparatus used in connection with the press. The top member I0 and bed I I are ordinarily interconnected oy strain rods which are here dotted in order to bring out clearly the other elements of the press. A control 10 rod I3 also interconnects the top member I0 and the bed II, and is mounted in the bores I4 and I5 thereof. The stop or cam member I6 is mounted for adjustable movement along the control rod I3, and may be clamped in any desired position by tightening the screw Il. The cam member or stop I6 is provided with a cam edge or surface I8 for operating a valve, 'in a manner hereinafter described.
The frame top member I0 is provided with a 20 cylinder I9 having a bore 20, within which a hollow ram 2| is adapted to reciprocate. A gland 22 and a packing 23 prevent leakage of fluid between the ram 2| and the cylinder bore 20. The ram 2| is provided'wlth a recessed head 24 and also with 25 an vinterior chamber 25 having an outlet bore 26 (Figure 4) near the bottom thereof. This bore 26 widens into a larger outlet bore 2'I forming an annular surface 28 between the bore 2l. and the outer wall 23 of the ram 2l. 30
Associated with the outer wall 29 are recesses 30 spaced at intervals around the periphery of the ram 2|. Between the apertures or bores 26 and 21 is an annular recess 3|. This recess 3| is provided with a plurality of threaded bolt 35 holes 32 for the attachment of the fluid-operated work-ejecting cylinder, generally designated 33. Also provided in the bottom wall 28 of the ram 2| are threaded bolt holes 34 serving for the reception of the bolts 35, by which the press 40 platen, generally designated 3.6, is secured to the ram 2|. The press platen 36 is provided with a hollow chamber 31 therein. and likewise with a bottom or pressing surface 38 having an aperture 39 therein for the passage of a work-eject- 45 ing plunger 40. Secured to the opposite end of the plunger 40 is a piston head 4I which reciprocates in a cylinder bore 42 within the workl ejecting cylinder 33. The latter is provided with a bore 43 for the passage of the ejecting plunger 50 40, a packing 44 and retaining plate 45 vbeing providedv for preventing leakage around the. plunger 40. The plate 45 is secured in position by means of the cap screws 46.
The bore 43 and thepacking 44 are mounted 55 '49 (Figure 3). The cylinder head 41 is provided with a threaded port 50 for the reception of a pipe 5|, by which fluid is admitted to the space beneath the piston head 4I. The cylinder head 41 is likewise provided with a bore 52 through which passes a, pipel 53, terminating within the threaded port '54 (Figure 2) leading to the passageway 55 within the walls of the main portion 48 of the cylinder 33. At its upper end the passageway 55 terminates in a threaded port 56 having the threaded connection 51, from which the pipe 58 passes to a threaded connection 59 secured within the threaded port 60 in the upper wall of the main cylinder portion 48. The pipe 53, passageway 55 and pipe 58 convey fluid to the space above the piston head 4I.
The cylinder portion 48 is provided with a marginal flange 6I which fits within the outlet bore 21 of the plunger or ram 2|. The pipes 5| and 53 pass throughthe hollow chamber 31 within the platen 36 by way of the opening 62 therein, and pass outwardly through an opening 63 in the top wall thereof to a valve 64. The latter is mounted upon a bracket 65 on the upper surface of the platen 36, and is provided with intake and exhaust lines 66 and 61, respectively. These lines 66 and 61 lead to any suitable source of pressure fluid, such as a pump, the distribu- ,tion of this fluid being effected by the valve 64.
The valve 64 is preferably a four-way valve of conventional construction, and is operated by a valve lever 68 having a roller 69 mounted on the upper end thereof, and adapted to be operated by engagement with the cam surface I8 of the cam or stop I6 as the platen 36 and ram 2| execute the various strokes of the press.
In the operation of the press and work ejector of this invention, the press is started upon its forward stroke by admitting pressure fluid to the space above the main ram 2|. Preferably a surge valve system (not shown) is employed to permit theram 2| to coast downwardly under the influence of gravity, and thereby approach the work more rapidly. As the platen 36 moves downwardly the lever 68 of the valve 64 passes the cam I6 so that the roller 63 engages the cam surface I8 to move the valve lever 68 counterclockwise. 'I'his action admits pressure fluid into the space beneath the ejector piston head 4|, thereby insuring that the ejector plunger 46.
will be in its retracted position at the time the platen 36 and its die engage the work. A
After the platen and the die or dies have completed the pressing stroke, the platen 36 begins its return stroke by the action of the usual return or push-back cylinders (not shown). As the valve 64 again passes the cam I6 on the return stroke of the platen 36, the roller 69 again engages the cam surface I8, swinging the valve lever 68 in a clockwise direction. This shifts the valve 64 to admit pressure uid into the space above the ejector piston head 4|, causing the ejector plunger 48 to move downwardly and eject the work-piece from the die. 'I'he length of the cam surface VI8 determines the length of time during which pressure iiuid will be applied to the ejecting cylinder 33, after which the valve roller 68 slips off the cam'surface I8 and causes the valve lever 68 to return to its ,hollow plunger structure.
neutral position, wherein the fluid is completely shut off.
After the platen returns to its top or retracted position, the ejector plunger 48 will, of course, be in its advanced or ejecting position, but will be again retracted when the valve 64 is again shifted by the engagement of the valve roller 63 with the cam surface I8 upon the next forward stroke of the platen 36. 'Ihe details of the four-way valve 64 form no part of the present invention as this valve is o1' any suitable conventional design. It is evident that in the operation of the four-way valve 64, when the pressure line 66 is connected through the valve 64 to one side of the ejector piston head 4|, the exhaust line 61 is automatically connected through the valve 64 to the space on the opposite side thereof.
The ejector plunger 40 and its piston head 4I may be operated by any suitable fluid, compressed air having been found convenient for this purpose. It will be obvious, moreover, that the application of this work-ejecting device is not conilnedv to fluid-operated presses, but may be employed equally well with mechanically-operated presses.
It will be understood that I desire to comprehend within my invention such modifications as come within the scope of the claims and the invention.
Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent, is:
1. In combination in a press, a main cylinder, a main plunger structure reciprocable relatively to said main cylinder and operated thereby, a double-acting work-ejecting cylinder and piston mounted on said plunger structure and movable therewith, a work ejector connected to said piston, an ejection control valve mounted on said structure and having a valve-operating member connected thereto, a stationary support mounted adjacent said plunger structure, and a valve-actuating cam adjustably mounted on said support and disposed in the path of travel of said valve-operating member, said valve-operating member being engageable with said cam to shift said valve at predetermined positions upon the forward and return strokes of said plunger structure to respectively retract andA advance said work ejector.
2. In combination in a press, amain cylinder, a main plunger structure reciprocable relatively to said main cylinder and operated thereby, a double-acting work-ejecting cylinder and piston mounted on said plunger structure and movable therewith, a work ejector connected tov said piston,an ejection control valve mounted on said 'structure and having a valve-operating member connected thereto, a stationary support mounted adjacent said plunger structure, and a valveactuating cam adjustably mounted on said support and disposed in the path of travel of Laid valve-operating. member, saidvalve-operating member being engageable with said cam to shift said valve at predetermined positions upon the forward and return strokes of said plunger structure to respectively retract and advance said work ejector, said main plunger structure being hollow and said work-ejecting cylinder and piston being mounted in the interior of said WALTER ERNST.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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US132574A US2173358A (en) | 1937-03-23 | 1937-03-23 | Press with work ejector |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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US132574A US2173358A (en) | 1937-03-23 | 1937-03-23 | Press with work ejector |
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US2173358A true US2173358A (en) | 1939-09-19 |
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US132574A Expired - Lifetime US2173358A (en) | 1937-03-23 | 1937-03-23 | Press with work ejector |
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Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2443814A (en) * | 1942-06-08 | 1948-06-22 | Joy Mfg Co | Forging apparatus |
US2482539A (en) * | 1943-11-04 | 1949-09-20 | Arrow Hart & Hegeman Electric | Air-operated press |
US2484879A (en) * | 1944-06-05 | 1949-10-18 | Hpm Dev Corp | Hydraulic press equipped with a synchronized stripping plunger |
US2625896A (en) * | 1948-03-15 | 1953-01-20 | Immenroth Otto | Rotary progressive die for presses |
US2694994A (en) * | 1950-05-27 | 1954-11-23 | Cooper Weymouth Inc | Air operated ejector for presses |
US2725769A (en) * | 1951-03-08 | 1955-12-06 | Case Co J I | Billet pointing device |
US2758652A (en) * | 1953-12-07 | 1956-08-14 | Danly Mach Specialties Inc | Hydraulic punch and stripper |
US3157111A (en) * | 1961-05-15 | 1964-11-17 | Avis Ind Corp | Work ejector for presses |
US3555949A (en) * | 1965-04-02 | 1971-01-19 | Smithe Machine Co Inc F L | Die cutting presses |
US3904416A (en) * | 1973-01-31 | 1975-09-09 | Toshiaki Onoda | Multistage cylinder |
FR2469272A1 (en) * | 1979-11-12 | 1981-05-22 | Kawasaki Yuko Kk | DOUBLE-ACTING HYDRAULIC PRESS |
US4368662A (en) * | 1979-03-09 | 1983-01-18 | Industrie-Werke Karlsruhe Augsburg Aktiengesellschaft Zweignieder-Lassung Keller & Knappich | Cylinder arrangement for friction-welding machine |
US5241896A (en) * | 1992-05-27 | 1993-09-07 | Phd, Inc. | Pneumatic cylinder apparatus |
US6276258B1 (en) | 1999-12-21 | 2001-08-21 | Ti Corporate Services Limited | Pressure activated piston and cylinder unit for use in a die |
-
1937
- 1937-03-23 US US132574A patent/US2173358A/en not_active Expired - Lifetime
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2443814A (en) * | 1942-06-08 | 1948-06-22 | Joy Mfg Co | Forging apparatus |
US2482539A (en) * | 1943-11-04 | 1949-09-20 | Arrow Hart & Hegeman Electric | Air-operated press |
US2484879A (en) * | 1944-06-05 | 1949-10-18 | Hpm Dev Corp | Hydraulic press equipped with a synchronized stripping plunger |
US2625896A (en) * | 1948-03-15 | 1953-01-20 | Immenroth Otto | Rotary progressive die for presses |
US2694994A (en) * | 1950-05-27 | 1954-11-23 | Cooper Weymouth Inc | Air operated ejector for presses |
US2725769A (en) * | 1951-03-08 | 1955-12-06 | Case Co J I | Billet pointing device |
US2758652A (en) * | 1953-12-07 | 1956-08-14 | Danly Mach Specialties Inc | Hydraulic punch and stripper |
US3157111A (en) * | 1961-05-15 | 1964-11-17 | Avis Ind Corp | Work ejector for presses |
US3555949A (en) * | 1965-04-02 | 1971-01-19 | Smithe Machine Co Inc F L | Die cutting presses |
US3904416A (en) * | 1973-01-31 | 1975-09-09 | Toshiaki Onoda | Multistage cylinder |
US4368662A (en) * | 1979-03-09 | 1983-01-18 | Industrie-Werke Karlsruhe Augsburg Aktiengesellschaft Zweignieder-Lassung Keller & Knappich | Cylinder arrangement for friction-welding machine |
FR2469272A1 (en) * | 1979-11-12 | 1981-05-22 | Kawasaki Yuko Kk | DOUBLE-ACTING HYDRAULIC PRESS |
US4375781A (en) * | 1979-11-12 | 1983-03-08 | Michio Bessho | Double-acting hydraulic press |
US5241896A (en) * | 1992-05-27 | 1993-09-07 | Phd, Inc. | Pneumatic cylinder apparatus |
US6276258B1 (en) | 1999-12-21 | 2001-08-21 | Ti Corporate Services Limited | Pressure activated piston and cylinder unit for use in a die |
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