US2172002A - Automatic diaphragm press - Google Patents

Description

Sept.v 5, 1939. R. w. STANLEY 2,172,002

AUTOMATIC ISIAPHRAGM Pnsss Filed Dec. s1, 195e 2 Sheets-'Sheet l ffy. Z

1N VENTOR.

Y fic/mrd f Wan/y Sept. 5, 1939. R. w. STANLEY 2,172,002

l AUTOMATIC DIAPHRAGM PRESS Filed'nec. s1, 195s 2 sheets-sheet 2 R y, o U @Wm m... Z r m o EE0 5 o M ww o o d o o 1M o o .M MU o o o o M SQNW o o iwwm. o o \\\\k o o `m ,w o o o o 4 o n c .w wf/o M o o @M du of.|||||||| ||\o w o o Patented Sept. 5, 1939 UNITED 'STATES' PATENT OFFICE AUTOMATIC DIAPHRAGM PRESS Richard W. Stanley, Lockport, N. uY., assigner to Merritt Engineering & Sales Co., Inc., Lockport, N. Y., a corporation of New York Application December 31, 1936, Serial No. 118,505

8 Claims.

proved construction adontrol for the operation of diaphragm presses such as described in the co-pending application Serial Number 744,132 of Ericsson H. Merritt, led September 15, 1934, now

l issued as Patent No. 2,148,704, dated February 28,

The principalobject of the present invention is to provide a diaphragm press having full automatic operation in combination with the feai tures of minimum mass in the head driving mechanism and minimum size in the head driving motor.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

l The invention accordingly/comprises the features of construction, combination of elements, arrangement of parts exemplied. in the construction hereinafter set forth; their scope of ap-` plication being clearly indicated in the appended l claims. Y

To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described, and particularly pointed out in the claims, the following description setting forth in detail certain illustrative embodiments of the invention, these being indicative however of but a few of the various ways in which the principle of the invention may be applied.

For a fuller understanding of the nature and objects of the invention reference should be had to the following detailed description taken in connection with the accompanying drawings-in which:

Figure 1 is a side view of a single opening press embodying the invention, imposed upon which is a wiring diagram showing the electrical circuit involved in one particular application of the invention. i

e Figure 2 is a section of a solenoid operated valve showing it in a discharging position.

Figure 3 is a detailed sectional plan showing the diaphragm clamps.

Figure 4 is a detailed view showing the diaphragm means and the associated members on an enlarged scale.

The diaphragm type presses first constructed for hot plate veneering, plywood formation and similar operations did not provide for the admission of Iiuid to partly inflate the diaphragm prior to final closing of the press.v Owing to the top head having to be moved down onto the Work mechanically to close up the daylight as it is termed in the art the material being pressed was thereby tightly clamped between the head 5 and the base prior to the application of the diaphragm pressure. 'I'his movement,y being effected by the power operated rotation of large nuts which actuated the downward travel of the head along the strain rods, ended by a jambing of the nuts upon their threads when the head came'to rest on the work. The diaphragm actuated pressing operation then took place, but upon its completion, forces of an impractical ,magnitude were required toovercome the frictional resistance of the nuts so they could be rotated in reverse to open the press to the desired extent. When a press of this character was supplied with steam heated plates and used as a hot-press, it was' also found diiiicult to provide heat-insulating means which would withstand the high mechanical pressures involved without destruction or loss of eiciency. Since th'e press operating diaphragm was of rubber or similar organic material it was desirable to protect it from excessive temperature. 'I'hus the first diaphragm presses presented two imperfectly solved problems in the excessive resistance to easy opening resulting from the jambing action at the end 'of the'closing movement and the excessive tendency of the rubber diaphragmf to become heated.

With the foregoing and other'considerations in mind 'the present invention solves these troublesome problems by providing means whereby. the press closes against a cushion of fluid vpressure in a partly inflated diaphragm which upon completion of the pressing operation -is completely deflated, thus freeing the material being clamped under reacti-Ve pressure btween the head and base, thereby permitting the head` to be raised 40 quickly and easily from the closed position.

Furthermore one of the means for accomplish- Aing this result involves a spring supported platen above and urged away from the diaphragmchamber so that Whenever the vpress is in an open position, metallic contact is broken between the heated members of ithe press and the' diaphragm chamber thus cutting off the iiow of h'eat from the steam platen to the diaphragm by interpos^ ing an air space between them.

The press illustrated in Figure 1 comprises base I0 which carries for instance four strain'rods l2. Placed above the base I0 is a head II which is vertically adjustable with respect to the posts. Resiliently mounted on base Ill is platen I4 sup- 55 Yes ported by fo'ur springs tu. .iotlie top surface oi the platen is attached steam plate is and to the lower side head il is attached steam plate i3. Steam plates it a'nd it are provided with steam chambers and are of metal so that their surfaces may rapidly be brought tb a high temperature so as to ht press plywood assemblies, as indicated 'at Il, or other -materials to be 'hot pressed.

In atcordance 'with the invention the head member is adjustably supported by means where- -i n it can be readily lowered 'until the steam plates i8 rest upon the work. and there is interposed between the platen member i4 and the base itl means whereby a high pressure may be developed so as to exert the necessary pressing of the work for bonding or other purposes.

As exemplied, the means for adjustably sup porting the head member il comprises supports 20 carrying internally threaded rotatable nuts 2l which t over externally threaded portions 22 on each of the strain rods l2. In order to rotate the nuts 2| there is provided suitable means which may include a two way electric motor 23 carried by bracket 2li.

The shaft 25 of the motor is provided with sheaves 26 connected by a suitably disposed belt 21 to sheaves 28 on rotatable sleeves 29 which are integral with the nuts 2i and each of which is mounted in `bushing 2da of support 2li. Accordingly when the motor is operatedthe head il and the parts carried thereby are readily lowered. against the work I1 As the plate I8 comes against the work, the motor may be turned ofi by any suitable means, one type of which is hereinafter exemplied Since the rotation of the nuts 2|y by the motor does not exert suilcient pressure for the usual bonding operation or other operations to be performed by the press, there is provided, between the platen i4 and the base l8,'diaphragm means whereby a chamber for the reception of iiuid pressure is provided. In the present instance there is illustrated diaphragm means consisting of a sheet of rubber 40 clamped' throughout its entire periphery to the top of base I0 and is securedto the base by frame -43 and bolts 44. The space between the diaphragm sheet 4U and the top surface of the base lli forms the diaphragm chamber, for the reception of fluid pressure, and as particularly clearly seen in Fig. l, the frame 43 also surrounds and forms a guide for the diaphragm plate 48. Fluid, for example, water, introduced under pressure through the tubular `members 41 readily works its way under the diaphragm, forcing the diaphragm sheet away from the top surface of the base I8 and exerting an upward pressure upon the diaphragm plate 46 suiilclent to perform the required pressing a0- tion between the platens. 'I'he inlet 41a is unique in being beveled or recessed. 'I'nis results in re-v markable advantages of averting valve-action by the diaphragm. against the edges, and of providing evenness of feed. The diaphragm plate 46 lits closely with the frame 43 and in conjunction with frame 43 forms a metallic restraining casing when the lflexible diaphragm sheet 40 is inflated, just as the casing or shoe of a pneumatic tire restrains the innertube from over n. A pressure'ior example, of 200 pounds per square inch may be appliedjn the case of the pressing of an ordinary plywood assembly. The upward movement of the iiexible diaphragm sheet 4l.

may be as. muchas an inch anda quarter.

The press is shown in Figure .l at the position just prior to nal clomng. I

ject to the control arranca In order to the migration oi heat from the steam plate I5 through to the diaphragm tt, and also to provide a movable member to eiect an automatic operating cycle after the head Il has descended so as to take up all of the daylight between the platens is and I8 and the work I'i, platen i4 is suspended on springs 30, a distance c above the diaphragm plate 46 Vwhen the press is in the opened position. To effect an automatic operating cycle and to provide for the release of the work Il after the iuid pressure has been exhausted from the diaphragm chamber an arrangement as shown in Figure 1 may be utilized. Thisincludes control circuits and a magnetic switch 52, the latter being ci any well-known commercial form in which a three wire line supply L', L?, L3, is'connected through respective sets of contacts O and C by electro-magnetically operated switch bars l5, 6, the bar band its associatedstructure serving to bridge the contacts in the set C for energizing the motor 2; to close the press, and the switch bar 6 with its associated structure serving to bridge the set of contacts O for reversely energizing the motor to open the press. The magnetic relay switch 52 is provided with control circuits c1, c, c3, c4, c5, which are in circuit with respective controlling means, including a manually-operated switch 50 to be employed by the operator for closing the press-and a manually-operated switch 6l to be employed by the operator -for opening the press. In control-connection also is a switch 54 which is mechanically operated near the end of the closing movement of the press, being carried for this purpose on the platen I4 to come in contact with an adjustable stem 55. The switch 54 is normally the platen i4 closed, and on striking the actuating, stem 55 is opened, thus breaking the circuit controlling the motor 23 and stopping the press against over"- run. The stem 55 being adjustable, permits of the close regulation ci the down cut-ofi point. Another similar switch 64 on the head Il, is normally in closed position, but inits path there is arrangedan actuating stop 6i, which when con tacted, opens the switch 84 to shut oil the current to the motor 23 and again stop the latter against over-run. Another switch 58, carried by the platen I4, is arranged in a control circhit with a magnetic switch 5s to control the same, the latter being in a circuit with a solenoid 59 whose plunger is arranged to operate a valve n between the duid-pressure pump and the expansible diaphragm 4l. The platen-carried switch I6 is arranged to b operated by a stem '51. preferably resilient, and mounted on the base Il. The circuit through the solenoid 59 thus subo! the magnetic switch Il is connected in parallel with themagnetic switch 52, to the line-supply L', I?. In circuit in connection also with the main-operating switches 5l, 8|-, is a further control` switch il which is operated by a small pressure-diaphragm on the conduit system 4 1 between the pump and the press. The press is shown at the position just prior to final closing. The close push button 5l has been manually depressed, thus closing the down circuit to the headJn'otor 23 through the down side of the reversing switch l2, thus causing-the-head to descend and contact the work I1. Further descent of the head causes depression of the platen i4, distance al so that inthe position shown the 4platen i4 is distance b above the diaphragm plate 4i. At this instant the normally limit switch 54 mounted on platen I4 has contacted adjustable stem II thus causing the Il limit switch to open the down circuit to the head motor 23. At the same instant the normally open solenoid valve limit switch 56 also mounted on platen I4 has contacted the resilient stem 51 mounted on the base, thus closing the circuit to solenoid valve switch 53 and energizing solenoid 59, thereby opening valve 60 to permit passage of water from the pump to the diaphragm through pipes 41.

After the down circuit to the head motor has been broken by the opening of the limit switch 54 the head II and the parts attached thereto may coast downward due to the inertia of their mass and thus decrease distance c, but during this time water is being admitted to the diaphragm chamber and raising the diaphragm plate 46 also decreasing the distance c so that when the head comes to rest there must of necessity be some degree of inflation of the diaphragm so that the diaphragm plate 46 is raised to some extent above its normal position when the press is open. l

In actual `operation if a sufficient degree of ination of the diaphragm cannot be secured before the head II comes to rest, the contact rod 55 may be so adjusted as to break the down circuit of the head motor by the initial downward movement of the platens I4. Also the normal distance c between the bottom surfaceof the platen I4 and the diaphragm 46 may be increased by adjusting the springs 3|) on their studs 3| by means of the nut 32.

In instances where it is desirable to operate the head up and down at extremely high speeds, the head motor 23 may be equipped with a solenoid brake so that the coasting of thehead II due to its inertia can be held within very close limits,

thus insuring the essential partial inflation of open push button 6I is manually depressed thus rst breaking the circuit to the solenoid valve switch 56 and de-energizing the solenoid 59 so that under the iniiuence of spring 62 the solenoid valves assume a position as shown in Figure 2, permitting the fluid in the diaphragm chamber to return to the supply tank. Second, the depression of the open button 6I closes the up circuit to the head motor 23 as far as the switch 63, and this up circuit is completely closed when the pressure in the diaphragm chamber falls to a pre-determined level, permitting the closing of the pressure limit switch 63, which, being in communication with the diaphragm chamber of the press has its plunger 63a, Fig. 2, pushed up by the same pressure fluid, and correspondingly by its stem 63h and switch stem 63e holds the switch bar 63d oi of the switch contact 63e; but when the pressure falls as predetermined the switch bar bridges the contacts 63e and completes the circuit to close contactor 53 of reversing switch 52 and energizing the head motor 23 causes it to raise the head II on the strain rods I2. Under the ,inuence -of the head motor the head continues to rise until the limit switch 64 contacts the adjustable stop 65, opening the up circuit.

Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims, or the equivalent of such, be employed..

I hereby particularly point out and distinctly claim as my invention:

1; A press, comprising relatively movable members, mechanical means to move at least one of said members, a platen movably mounted on one of said members, iluid-expansible diaphragm means between said platen and its associated vmember, means for releasing iuid from said diaphragm means, and means actuated by the drop in pressure in the diaphragm means for starting the operation of the said mechanical means to open the press, whereby binding. resistance against the opening movement is eliminated.

2. A press, comprising relatively movable members, an electric motor to move at least one of said members, a platen movably mounted on one of said members, an expansble rubber diaphragm sheet between said platen and its associated member, a diaphragm plate and means in common for securing the diaphragm sheet and guiding the diaphragm plate; said means including a frame surrounding said diaphragm plate as a guide therefor and for clamping the edges of said diaphragm sheet to its associated press member, a fluid-pressure connection having a beveled inlet between said sheet andv its associated member,-

a valve for controlling ilow of pressure iiuid to and from the space between said expansible rubber sheet andl its associated member, a manually actuated electric switch for opening said valve to release pressure uid, an electric switch actuated by predetermined drop in pressure in said diaphragm means for starting the motor to open the press, switch means for automatically stoppingl the motor when the press is open, switch means for starting the motor to close the press, and cooperating electric switch means for admitting the pressure uid to the diaphragm before the press is closed, and switch means for automatically stopping the motor when the press is closed. A

3. A press, comprising relatively movable members, an electric motor to move at least one of said members, a platen movably mounted on one of said members, an expansible rubber diaphragm sheet between said platen and its associated member, a diaphragm plate and means in common for securing the diaphragm sheet and guiding the diaphragmrplate, said means including a frame surrounding said diaphragm plate as a guide therefor and for clamping the edges of said diaphragm sheet to its associated press member, a duid-pressure connection having a beveled inlet between said sheet and its associated member, a

valve for controlling ilow oi pressure iiuid to and from the space between said expansible rubber sheet and its associated member, a manually actuated electricswitch for opening said valve to release pressure fluid, an electric switch actuated by predetermined drop in pressure` in said diaphragm means :for starting the motor to open the press, switch means for automatically stopping the motor when the press is open, switch means for starting the motor to close the press, and cooperating electric switch means for admitting the pressure fluid to the diaphragm before the press is closed. l l' 4. A press, comprising relatively movable members, an electric motor to move at least one of said members, a'platen movably mounted on one of said members, an expansible rubber diaphragm sheet between said platen and its assocated member, a diaphragm plate and means in common for securing the diaphragm sheet and guiding the diaphragm plate, said means including a frame surrounding Vsaid diaphragm plate as a guide therefor and for clamping the 15 dedges of said diaphragm sheet to its associated press member, a fluid-pressure connection havlng a beveled inlet between said sheet and its associated'member, a valve for controlling ow of pressure fluid to and from the space between said expansible rubber sheet and its associated member, a manually actuated electric switch for opening said valve to release pressure fluid, an electric switch actuated by predetermined drop in pressure in said diaphragm means for starting the motor to open the press, switch means for starting the motor to close the press, and cooperating electric switch. means for admitting the pressure fluid to the diaphragm before the press is closed.

5.A press, comprising relatively movable members, an electric motor to move atleast one of said members, a platen movably mounted on one of said members, an expansible rubber sheet between said platen and its associated member, a frame surrounding said platen as a guide therefor and for clamping the edges of said rubber sheet to its associated press member, a iluidpressure connection having a beveled inlet between said sheetand its associated member, a valve for controlling ow of pressure fluid to and from the space between said expansible rubber sheet and lts associated member, a manually actuated electric switch "for opening said valve to release pressure fluid, an electric switch actuated by predetermined dropsin pressure in said diaphragm means for starting the motor to open the press, and switch means for `automatically stopping the motor when the press is closed..

.6. A press, comprising srelatively movable members, an electric motor to move at least one of said members, a platen movably mounted on one of said members, an expansible rubber sheet between said platen and its associated member, a

frame surrounding said platen as a guide there' for and for clamping the edges of said rubber sheet to its associated press member, a uidpressure connection having a beveled inlet between said sheet and its associated member, a valve for controlling iiow of pressure fluid to and from said expansible rubber sheet, a manually actuated electric switch for openingsaid falve to release pressure fluid from the diaphragm means, and an electric switch actuated by predetermined low pressure under said rubber sheet for starting the motor to open the press.v

'1. A press, comprising relatively movable members, mechanical means for moving at least one of said members, a platen movably mounted on oneA of said members, uidexpansible diaphragm means between said platen and its associated member, a valve for controlling ow of pressure uid to and from said diaphragm means, a manually actuated electric switch for opening said valve to release pressure uid from the diaphragm means, an electric switch actuated by predetermined low pressure in said diaphragm means for starting the mechanical means to open the press, means for starting the mechanical means for closing the press, and cooperating electric switch means for admitting pressure uid tothe diaphragm means before the press is closed. I

8. A press, comprising relatively movable members, mechanical means for moving at least one of said members, a platen movably mounted on one of 'said members, means between said platen and its associated member, a valve for controlling flow of pressure uid to and from said diaphragm means, a manually actuated electric switch for opening said uid-expansible diaphragm' valve to release pressure fluid from the diaphragm means, and a switch actuatedby predetermined low pressure in said diaphragm means for starting the mechanical means to open the press.

' RICHARD W. STANLEY.

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