US2139091A - Control mechanism for pressing machines - Google Patents

Description

1933- v E. N. NECKEL 2,139,091-

CONTROL MECHANISM FOR PRESSING MACHINES Filed Nov. 4, 1937 2 Shets-Sheet 1 FIG.- I

ATTORN EYJ Dectfi, 1938. v E. N. NECKEL 2,139,991

CONTROL MECHANISM FOR PRESSING MACHINES Filed Nov. 4, 1937 2 SheetsSheet 2 INVEN I'OR 66 H EDMUND N. NECKEL ATTORNEYS Patented Dec. 6, 1938 UNITED STATES CONTROL MECHANISMFO'R PRESSING MACHINES Edmund N. Neckel, Cincinnati; Ohio, assignonto The American Laundry Machinery Company,. Norwood, Ohio, a corporation of Ohio Application November 4, 1937, SerialNo'. 172,686.

6 Claims.

This invention relates to improvements in control mechanism for pressing machines.

An object of the present invention is the improvement of control mechanism for power pressing machineswhich are closed by two stages of movement, a firststage into a safe-closed positionand a second stage into final pressing position. In my improved control'mechanism, motor means is provided for causing these two stages ofrpress closing movement and the control means for the second stage movement producing motor means includes a control member operable by movement of the press to safe closed position and another control member operable by move ment of the first stage movement producing motor control means to motor deenergizing position.

A specific form of my improved control mechanism is applied to a machine wherein each pressing member is movable relative to the other and control means is provided for first moving one member into pressing position by means of its motor andasecond control means and motor for moving the other pressing member into engagement with the first member. The control means for energizing thissecond acting motor comprises a member positioned by the press parts as they reach safe closed position and a member placed in operative position when the control means for the first motor is released. A specific employment of this improved control is its applicationto' a machine having movable head and bed pressing members with a fluid motor for moving each member and wherein two-hand control'means is provided for first moving the pressing; head to pressing position, whereupon a valve in the supply line for the bed moving motor is moved tosupply position but the latter is ineffective to supply fluid to the bed moving motor until the control means for the head movingimotor is released, at which time an additional valve is actuated rendering effective the fluid supply for the bed moving motor, In the specific form of this device shown, strut forming parts are placed in position when the head reach-es pressing position and these are adapted to resist pressure of the bed against the head so that when the head moving motor is deenergized the press will nevertheless remain closed.

Other objects and advantages of my improved control mechanism will be apparent from the accompanying drawings and the specification describing the same and the essential features willbe summarized in the claims.

In the drawings, Fig. l. is an end elevationof a pressing machine with the parts in open position and with my improved control mechanism shown diagrammatically; Fig. 2 is a view similar" to Fig. 1 showing the press in safe-closed position with the control mechanism moved to corresponding position; Fig. 3 is another similar view" showing the parts fully closed andwith the con' trolmechanism in corresponding position; while Fig. 4 shows a modified form of valve mechanism. controlling the final pressure application of the machine.

While my improved control mechanism.migh'tz be applied to various types of pressing machines utilizing various forms of motive power and while the same might be applied'to a pressing machine wherein one member only was movable in two stages toward the other member; I have chosen to illustrate the same as appliedto a machine wherein each of the pressing membersis movable relative to the other and each is supplied with its own fluid actuated motor. In the machine shown on a frame I0 is mounted a bracket l l which supports a pressing bed [2 mounted for vertical reciprocation relative to the frame and bracket as by means of a pin l2a extending in suitable openings to guide the vertical movement of the bed. Spring pressed pins l3 normally hold! the bed in its lowermost position. Pivotally mountedon the frame is a head lever l4 which by its oscillation carries thepressing head l5:' toward and from the pressing bed. This movement of the head lever is produced by means of 1 motor l6 whose piston rod I! is connected to one" or more toggles l8 mounted betweenthe frame and the rear end of 'the head lever. A spring!!! biases the head toward open position. Movement of the pressing bed is caused by motor-20 whose piston rod 2| is connected to the bellcrank lever 22 which is pivoted to the frame at 23 and whose shorter lever arm engages pin l2a at the point 24. As the toggle l8 moves over center when the press is closed a spring pressed plunger 25 is provided for giving an initial kick when the press is opened to throw the toggle back over center.

The fluid supply for motor I6 is preferably of the type controlled by two hands so that the hands of the operator are both occupied until the press reaches a safe closed position, thus preventing the injury of the hand between the press closing members. While various types of such safety two-hand controls are well known in this art, I have shown one involving two valves operable by manuals so spaced apart at the front of the press as to require ahand ofthe operator on each of them for their simultaneous operation.

The supply for motor I6 is thus by way of conduit 26, valve casing 21, conduit 28, valve casing 29 and conduit 30. Valve casing 21 carries a normally closed inlet valve 21a and a normally open outlet valve 21?) both mounted on stem.2'|c which is operable by manual 21d. Casing 29 houses similar parts which are given similar suffixes and are operable by manual 28d. However, valve stem 29c passes througha fluid-tight partition 3| and carries in the chamber on the far side of this partition another valve 29c for a purpose later described. It will be obvious from an examination of the drawings that when the valves thus described are in the position of Fig. 1, motor I6 is exhausted to atmosphere and both manuals must be depressed and held depressed to energize motor Hi. It will be noted also that valve 29a is open in the normal position of the valves.

The fluid supply for motor is by way of supply conduit 32, valve casing 33, conduit 34, chamber of casing 29 and conduit 36. In casing 33 is a valve preferably of the stay-put type and here illustrated as a slide 33a operable by manual 33b and also operable by the servomotor 31. The slide 33a has an exhaust position as shown in Fig. 1 wherein the port in the slide connects conduit 34 with the exhaust port 330. It has also a supply position as shown in Fig. 2 where the port in the slide connects conduits 32 and 34. The mechanism shown at 31 is for the purpose of moving slide 33a to its fluid supply position when the press parts have reached a safe closed position. While there are several ways of doing this, I have illustrated the servomotor 3'! supplied with motive fluid through conduit 38 and a port 39 in the cylinder wall of motor l6 which port is uncovered by the piston of motor 6 when the pressing head reaches safe closed position. Thus motive fluid for servomotor 3'! is supplied through conduit 30, the cylinder of motor l6 and conduit 38.

It is thought the operation of my improved control mechanism will now be apparent. With the pressing members in the position of Fig. 1, the operator arranges work to be pressed on the bed l2 and actuates manuals 21d and 29d to the position of Fig. 2. This opens valves 21a and 29a at the same time closing valves 21b and 29b. Fluid is then supplied to motor I6 and toggle l8 moves over center to the position of Fig. 2, placing the pressing head in a safe position adjacent the bed l2. While manual 29d is depressed valve 296 remains closed. When the head reaches the safe closed position of Fig. 2, fluid is supplied to servomotor 3'l'thus moving the slide 33a to the supply position but fluid passing through conduits 32 and 34 cannot pass chamber 35 because of the closed valve 29c. To complete the closing of the press the operator releases manuals 27d and 29d as shown in Fig. 3, thus deenergizing motor l6 and servomotor 31 but at the same time valve 29c is opened permitting fluid to flow through conduit 36 to motor 20. This raises the bed l2 into pressing engagement with the head l5 and acting back through the head lever holds the toggle IS in its strut forming position when motor I6 is deenergized. The pressure upwardly of bed l2 exerted against the head I 5 is resisted by the toggle IS in its over center position so that the thrust is carried to the base of frame [0. It will thus be noted that motor 23 cannot be energized until the press is safely closed for positioning valve 33 and until manual 29d isreleased, placing valve He in supply position. In other words, the valves 33 and 296 are in series in the fluid supply line for motor 20. While other means might be utilized for holding the valve 33 in supply position, I find it convenient to simply make this valve of the stay-put type which by means of manual 331) may be returned to the exhaust position of Fig. 1 to permit the press to open under the influence of plunger 25 and spring l9.

An alternative form of stay-put valve for use as a substitute for valve 33 is shown in Fig. 4. This valve comprises a casing 40 having two compartments, one housing the normally closed inlet valve 4011 on stem 43b and the other housing normally open outlet valve 400 on the stem 40d. These valve stems have pin and slot connections with the T-shape lever 4| pivoted at 42 and supplied with the over center spring 43 which upon oscillation of lever 4| passes from side to side of pivot 42 so as to hold valves 40a and 400 in any position in which they are placed. The supply for motor 20 in this case would be through conduit 44, valve 40a, conduit 45 and the chamber 35 of valve casing 29 and conduit 36 as previously described. A conduit 45a permits the exhaust from motor 20 through outlet valve 400. Here the servomotor 31' carries out the same function as servomotor 37 already described and may be supplied with fluid through conduit 38 from motor I 6 as previously described. The operation of a press supplied with the valve mechanism of Fig. 4 would be exactly the same as that already described, the lever 4| being moved to the broken line position of Fig. 4 by servomotor 3'! when the press is closed and returned manually to the full line position of Fig. 4 to cause press opening.

What I claim is:

1. In a pressing machine, a pair of coacting pressing members relatively movable into pressing engagement in two stages, a first stage into a. safe-closed position and a second stage into final pressing position, motor means for causing first and second stage movement of said pressing members, control means for causing first stage movement of said motor means including a control member movable to on and off positions, and energizing means for causing second stage movement of said motor means including a control member operable by movement of said pressing members to safe-closed position and a control member operable by movement of said first named control member to off position.

2. In a pressing machine, a pair of coacting pressing members relatively movable into pressing engagement in two stages, a first stage into a safe-closed position and a second stage into final pressing position, two motors, one for causing each stage of movement, a control member for said first stage motor movable to energizing and deenergizing positions, and energizing means for said second stage motor including a control member movable to energizing position by movement of said pressing members to safe-closed position and a control member movable to energizing position by movement of said. first stage motor control member to deenergizing position.

3. In a pressing machine, a pair of coacting pressing members relatively movable into pressing engagement in two stages, a first stage into a safe-closed position and a second stage into final pressing position, fluid actuated means for causing first and second stage movement of said pressing members, two-hand control means for causing first stage movement of said fluid actuated means, said control means including a control member movable to supply and cut-off positions, and fluid supply means for causing sec- 0nd stage movement of said fluid actuated means, said supply means including a valve movable to supply position by movement of said pressing members to safe-closed position and a control valve operable by movement of said control member to cut-off position.

4. In a pressing machine, a pair of coacting pressing members each movable toward and from the other, first and second fluid actuated means for moving said members respectively relative to each other, a fluid supply for said first fluid actuated means including tWo-hand-operated valve means, and a fluid supply for said second fluid actuated means including a valve movable to supply position by movement of said valve means to cut-off position and a valve movable to supply position by movement of said pressing members to safe-closed position.

5. In a pressing machine, a pair of coacting pressing members each movable toward and from the other, a fluid motor for moving one of said members, fluid actuated means for moving the other of said members, a two-hand control for said motor including a normally closed inlet valve and a normally open exhaust valve, a third valve opening and closing with said exhaust valve, a fourth valve having supply and exhaust positions and being adapted to stay in either position when placed there, a servomotor for moving said fourth valve to supply position, a fluid supply for said servomotor including a port uncovered by movement of said fluid motor sufficient to move said one pressing member to pressing position, and a fluid supply for said fluid actuated means including said third and fourth valves in series.

6. In a pressing machine, a pair of coacting pressing members each movable toward and from the other, a fluid motor for moving one of said members into pressing position, mechanism between said motor and said one member adapted when said one member is in pressing position to resist pressure from said other pressing member and to be held in resisting position independently of said motor, fluid actuated means for moving the other of said members, a two-hand control for said motor including a normally closed inlet valve and a normally open exhaust valve, a third valve opening and closing with said exhaust valve, a fourth valve having supply and exhaust positions and being adapted to stay in either position when placed there, a servomotor for moving said fourth valve to supply position, a fluid supply for said servomotor including a port uncovered by movement of said fluid motor sufficient to move said one pressing member to pressing position, and a fluid supply for said fluid actuated means including said third and fourth valves in series.

EDMUND N. NECKEL.

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