US2224881A - Machine for making pulp articles - Google Patents

Description

5 Sheets-Sheet l E M. PATERSON ET AL MACHINE FOR MAKING PULP ARTICLES Filed Dec.

Dec, 17, 194-9.

INVENTOR.

1940- E. M. PATERSON ETAL 2.224.381

MACHINE FOR MAKING PULP ARTICLES Filed Dec. 28, 1936 5 Sheets-Sheet 2 INVENTORS i ATTORNEYS Dec. 17, 1%).

E. M. PATERSON ET AL MACHINE FOR MAKING PULP ARTICLES Filed Dec. 28, 1936 5 Sheets-Sheet 3 INVENTOR. dU/O/id 777/. 7

J Mm BY a fi ATToRNsvs 194% E. M. PATERSON ETAL MACHINE FOR MAKING PULP ARTICLES Filed Dec. 28, 1936 5 Sheets-Sheet 4 O INVENTOR5 17, 1940- E. M. PATERSON ETAL MACHINE FORNMAKING PULP ARTICLES Filed Dec. 28, 1936 5 Sheets-Sheet 5 gm 0. 7) Ef g 4 w 1 6 1J I m fi ATTORNEYS Patented Dec. 17, 1940 "UNITED STATES MACHINE FOR MAKING PULP ARTICLES Edward M. Paterson, Whittier, and Ray 0. Wilson, Los Angeles, Calif., assignors to Plastic Fibre Corp., a corporation of California Application December 28, 1936, Serial No. 117,804

1 Claim.

This invention relates to the manufacture of articles from paper pulp and the like and more particularly to methods of and machines for molding articles from thin wet pulp material in a single operation.

An object of the invention is to produce relatively thin molded pulp articles in which the pulp fibers are so interlaced and extended in various directions as to provide maximum strength in the finished'article.

A more specific object is to provide a porous mold or die for simultaneously shaping thin articles from a mixture of pulp suspended in liquid and squeezing out the excess liquid, in

which the liquid is discharged from the mold in such away as to leave the pulp fibers in the finished article in such positions as will impart maximum strength to the article against cleavage in response to bending strains.

Another object is to provide an automatic machine comprising separable molds or dies capable of operating continuously to receive pulp material and discharge pressed pulp articles at definite intervals.

Various more specific objects, and features of the invention, will become apparent from the detailed description to follow of a machine in accordance with the invention for making pulp coat hangers. In accordance with the present invention, we produce thin pressed pulp articles of uniform substantial strength throughoutby staggering all the discharge-pores in each die face with respect to the pores in the other die face.

The invention will now be explained by describing in detail a complete machine for pressing pulp coat hangers, it being understood that various departures can be made from the particular structure shown without departing from the invention.

In the drawings:

Fig. 1 is a side elevation of a complete pulp press in accordance with the invention;

Fig. 2 is a sectional view of the machine, the

section being taken substantially along the line II-II in Fig. 1;

Fig. 3 is a detail section through the pulp reservoir of the machine, the view being taken along the line III-III in Fig. 2;

Fig. 4 is a detail longitudinal vertical section taken through the center of the mold;

Fig. 5 is a fragmentary plan view, partly in section, of a part of the mold and its actuating mechanism;

Fig. 6 is a detail transverse section through the mold, the section being taken along the line VIVI of Fig. 5;

Fig. '7 is a detail cross section taken through a portion of one of the plunger dies, the section being taken along the line VII-VII in Fig. 6 with member l6 omitted;

Fig. 8 is a rear view of one of the forms and plungers of the press showing certain elements in section, the view being taken looking .in the direction of the arrows in Fig. 5;

Figs. 9', 10, 11, 12 and 13 are schematic views showing the elements of the press. in successively different positions of operation.

Fig. 14 is a detail section taken through one of the plunger dies parallel to and adjacent the end of the plunger, the section line being indicated at XIV-XIV in Fig. 13.

Fig. 15 is a greatly enlarged detail longitudinal section through the ends of two juxtaposed plungers showing the disposition of the apertures therein, the section being taken in the plane XV- XV of Fig. 14.

Fig. 16 is an elevation view 'of a. completed coat hanger made in accordance with the invention.

Fig. 17 is a detail cross section through a portion of the coat hanger, the section being taken in the plane XVIIXV1I of Fi 16.

The particular machine disclosed in the drawings is intended for the manufacture of coat hangers, such as shown in Fig. 16, from paper pulp or other fibrous plastic material.

Hangers of this type comprise an upper curved bar I connected at its outer extremities to the extremities of a straight lower bar 2 which serves to reinforce the, upper bar 1 and also function .as a support over which the trousers of a suit of clothes may be hung. The hanger is provided with a hook 3 made of wire and having a straight lower section terminating in an enlarged head 4 which is embedded in the upper bar I. The head 4 prevents the hook 3 from pulling out of the bar, although by virtue of the fact that the wire and the head embedded, in the bar are round, the hook may be rotated. Hangers of the type illustrated in Figs. 16 and 1'7 may be molded complete in one operation from a mixture of pulp suspended in water in the machine now to be described.

Referring first to Figs. 1' and 4, our machine comprises a sturdy supporting frame 10 of cast iron or other suitable material on which the various moving parts of the machine are supported in proper relative positions. The mold or die proper consists of a pair of generally similar side forms II and 12, respectively, which define passages having the same cross sectional dimensions as the hanger to be manufactured, and a pair of similar plungers I3 and I4, respectively, which fit within the side forms II and I2, respectively, and seal therewith.

The ends of the plungers l3 and I4 compress the fiber mixture within the forms I I and I2 and the ends of the plungers in contact with the pulp define the shape of the opposite faces of the finished hanger. As shown to best advantage in Fig. 4, the form I I is provided with a core I5 and the form I2 is providedwith a core I6, which cores define the openings in the finished hangers. The cores I5 and I6 are rigidly attached to the forms II and I2, respectively, by base plates I1 and I8, respectively. The inner ends of the forms II .and I2, and their cores I5 and I6, are ground square and smooth to define contact faces which, when the two forms are pressed together, meet to form a substantially fluid-tight joint. To reduce the possibility of foreign matter lodging between the contact faces of the forms, the outer edges of the formed ends are preferably beveled as indicated at I9, thereby reducing the width of the ground faces which contact each other. The faces of the two forms are slightly recessed to permit entry therebetween of the hook 3 of a hanger to be molded, and a notched guide plate 20 is preferably provided on top of the-form I I to aid the operator in aligning the hook 3 when the latter is inserted between the forms.

The forms II and I2 are slidably supported for movement toward and away from each other by a pair of slide bars 22 and 23, respectively, which extend longitudinally across the machine and are supported at opposite ends in brackets 24 attached to the frame III. The bars 22 and 23 are positioned slightly above the main portions of the forms II and I2 adjacent the side edges of the latter, and brackets 25 and 26 having eyes therethrough for receiving the bars 22 and 23, respectively, are formed integral with the forms. By means of the mounting described, the forms II and I2 are positively supported for free longitudinal motion along the bars. The plungers I3 and I4 are slidably supported in turn by the forms II and I2, in which they are slidingly fitted.

. In the operation of the machine the forms II and I2 and the plungers I3 .and I4 are recurrently reciprocated through definite paths to receive a charge of pulp, compress it into a hanger, discharge the hanger, and then repeat the cycle. To move the forms and plungers the proper distances in the proper sequence, a cam driving mechanism is employed. This cam mechanism comprises a main cam shaft 21 which extends transversely of the machine below the forms II and I2 and is journaled in bearings 28 and 29 in the frame Ill.

The shaft 21 has a worm gear 39 keyed to one end thereof as shown in Fig. 2, which worm gear functions to drive the shaft 21 and is in turn driven by a worm 3| on a drive shaft which may in turn be rotated from any suitable source of power.

Keyed to the cam shaft 21 between the bearings 28 and 29 are three cams 32, 33 and 34. Each of the cams 32 and 34 has a single cam face cooperating with cam followers 31 (Fig. and 38 (Fig. 2), respectively, which followers are linked to the forms I2 and I I, respectively. The central cam 33 has two identical cam faces cooperating with cam followers 39 and 40, respectively, which are linked to the plungers I4 and I3, respectively.

The linkage for coupling the cam follower 38 to the form II comprises a yoke M to which the follower 38 is rotatably secured and which yoke is slidably supported for horizontal movement by a bushing 42 having parallel upper and lower faces which slidably engage the yoke 4|. The bushing 42 is drilled to receive the shaft 21 upon which it floats between the cams 34 and 33. The yoke M is pivotally connected by a rod 43 to the lower end of a lever 44 fulcrumed on a stationary shaft 45 supported on the frame Ill. The upper end of the lever 44 is connected by a yieldable link 46 to a bracket 41 projecting from the plate I! which, as previously described, is anchored to the form II.

The flexible link 46 consists of a pair of levers 48 and 49, respectively, which bear against and fulcrum on a pin 59 positioned therebetween. The lower end of the lever 48 is pivotally connected by a pin 5I to the upper end of the lever 44 and the lower end of the lever 49 is pivotally connected by a pin 52 to the bracket 41; Compressive strains applied to the lower ends of the levers 48 and 49 tend to separate the upper ends of the levers. Such separation is resiliently resisted by a helical spring 53 surrounding a bolt 54 which extends through eyes provided therefor in the upper ends of levers 48 and 49. The bolt 54 has a head 55 on one end which bears against 'the lever 49 and a nut 56 is provided on the other end of the bolt for compressing the spring 53 between the nut and the upper end of the lever 48. The upper ends of the levers 48 and 49 are preferably made substantially longer than the lower ends so that a substantial amplification of force may be obtained and the necessary spring force supplied by a relatively light spring.

The link mechanism for connecting the cam follower 31 to the form I2 is substantially identical with that described for connecting the cam follower 38 with the form II; thus it consists of a yoke 4|, bushing 42 (floating on the shaft 21 between the cams 32 and 36), rod 43', lever 44' and yieldable link 46'. The construction of the yieldable link 46' is identical with that of the link 46 and need not be described in detail.

The cams 32 and 34 function to move the cam followers 31 and 38 outwardly to positively force the forms II and I2 together. To retract the forms and cause the followers to remain in contact with their associated cams, a helical tension spring 57 is connected at opposite ends to the lower ends of the levers 44 and 44'.

The cam followers 39 and 40, cooperating with the cam 33 for actuating the plungers I4 and I3, respectively, are connected to their associated plungers by lever and toggle mechanisms. Thus the follower 4D is rotatably mounted on the inner end of a lever 58 which is fulcrumed near its center on a stationary shaft 59 supported in the frame I0, and the outer end of lever 58 is pivotally connected to the lower end of a yieldable connecting rod 60. The yieldable connecting rod 60 is identical with a corresponding rod 60 associatedwith the cam follower 39, and since the latter is shown in section in Fig. 4, the construction will be described with reference to the rod 60'. Thus the yieldable connecting rod 60' comprises a lower rod 6I having a nut 62 on its upper end which supports a washer 63 hearing against the lower end of a helical compression spring 64. The upper end of spring 64 bears against a flange 65 on a socket member 66 which is screwed onto the lower end of an upper rod 61.

A pin 68 of reduced diameter extends from the upper end of the lower rod 6I, passing through bushing 69 screwed into the lower end of the socket member 66. Pin 68 has a head I0 on its upper end which is reciprocal through a short distance within the socket member 66. When no compressive force is applied to the rod 60, the rods BI and 61 are in separated positions as shown in Fig. 4, but when thecompressive force applied to the rod 60 exceeds a predetermined value, the spring 64 yields, permitting the pin 68 to slide into the socket 66.

The upper end of the rod 60 connects to a bearing member 'II which isrotatably mounted on a movable shaft 12 substantially at the center of the latter. Also rotatably mounted on the movable shaft I2 on opposite sides of the bearing member 'II (Fig. 5) are the bearing ends I3 of a pair of links I4 formed integrally with, arid extending from, a sleeve 15 rotatably mounted'on a shaft I6 supported in brackets 11 extending from the frame I0 of the machine. Rotata-bly mounted on the outer ends of the movable shaft 12 are the bearing ends I8 of a pair of links I9, the inner ends of which terminate in bearing members rotatably mounted on pins 8| supported in bifurcated brackets 82 secured to the rear end of the plunger I4. p

The plunger I3 is similarly connected to the upper end of the yieldable connecting rod 60' by members 'II' and 82' inclusive.

In operation as the rotation of cam 33 forces the cam followers 39 and 40 downwardly, the levers 58 and 58 are rotatedto move the rods 60 and60' upwardly, thereby moving the shafts I2 and I2 upwardly and moving the links I4 and I9, and I4 and I9 upwardly at their lower ends to thereby shift the plungers I4 and I3, respectively, inwardly. As the shafts I2 and I2 approach the common plane of shafts I6 and shafts 8|, the force on the plungers is greatly multiplied, which is highly desirable in view of the increased resistance offered to the plungers by the pulp as it becomes more highly cor'n-, pressed.

To retract the plungers I3 and I4 and maintain the cams 39 and 40 in contact with the cam 33, tension springs 83 and 83 are connected between the outer ends of the levers 58 and 58', respectively, and stationary pins 84 and 85, respectively, anchored to the frame I0 of the machine. I

The earns 32, 34 and 33 are so shaped as to provide a desired sequence of movements of the forms and the plungers. However, before describing this movement, certain auxiliary mechanisms' will be described which function in synchronism with the particular sequence of form and plunger movement utilized.

Thus the compression chamber defined by the plungers and the forms must be filled with the pulp and water mixture during each cycle of operation. To introduce apulp and water mixture into the form, a port is provided in the upper side of form I2, which port communicates through a manifold 89 consisting of a fitting 9I and a flexible hose connection 92 with the lower end of a storage reservoir 93, which is also communicated through a manifold 94, extending from the upper side thereof with a main pulp tank mounted on the top of the machine and constantly kept at least partially filled with a dilute mixture of pulp and water. The

reservoir 93 v(referring to Fig. 3) comprises a cylindrical container stationarily supported on the frame of the machine and having therewithin a sleeve valve 96 mounted on a shaft 91 which is journaled for rotation in the end walls of the container 93 and extends therebeyond at one end and has keyed to that end a crank arm 98 which is connected by and 99 to a lever I00 vi'nich is mounted on the outer end of the stub shaft 59', which extends through the frame I0 on the exterior side thereof. This lever carries a cam roller I-02 which bears against the under side of a cam I03 keyed to the outer end of the cam shaft 21. A tension spring I04 is connected between the extreme outer end of the lever I00 and the frame of the machine at a point thereabove to retract the lever I00 and maintain the cam follower I02 against the cam I03.

The cam I03 periodically moves the lever I00 and the rod 99 from the normal position shown in Fig. 1 and Fig. 3 through a distance sufficient to rotate the crank arm 98 through substantially 60, retain it in that position for an interval,

. and then release it, the spring I04 restoring the valve to the normal position. In the normal position as shown in Fig. 3, a port I05 in the valve sleeve 96 is in registration with the manifold 94 extending to the supply tank 95 so that under these conditions the reservoir 93 fills with a mixture of pulp and water from the tank 95. When the crank 98 is rotated through substantially 60 as described, the port I05 first passes out of registration with the manifold 94 and thereafter a port I06 moves into registration with the manifold 89 leading to the form I2. However, the port I06 does not begin to register with the manifold 99 until afterthe 'port I05 has moved completely out of registration with the manifold 94.

While the port I06 is in registration with mani- I05 in the valve 96) as the port I06 reaches full registration in position with the manifold 89.

Thus the air line I0! is provided with a valve I08 therein (Fig. 1) which valve has an actuating handle I09-positioned in the path of a trip I I0 clamped on the rod 99 so that as the rod completes its downward movement, the trip I I0 bears against the handle I09 to open the valve I08. However, as soon as the rod 99 starts its return movement, the trip I I0 leaves the handle I09 and the valve I08 automatically closes.

To prevent a hanger adhering to one or the other of the forms or plungers as the latter are retracted, we provide a means for engaging the hanger hook 3 and preventing longitudinal motion of the latter during retraction of the forms and plungers. This means consists of an arm I I I having a bifurcated downwardly depending tip on its outer end adapted, when the arm is in the position shown in Fig. 2, to enclose the curved part of the hanger hook 3. The arm I I I is keyed to a shaft II2 which extends longitudinally of the machine and is supported in bearing members II3 adjacent its ends. There is also keyed to the shaft 2 a short arm II4, the outer end of which is pivotally connected to the upper end of a rod I I5 which is slidably supported adjacent its lower end in a stationary guide I I6.

The extreme lower end of the rod II5 carries a pin III which extends into a slot H8 in one end of a lever H9 which lever is fulcrumed on a stationary pin I20 secured to the frame of the machine and carries on its opposite end a cam follower I2I which bears against a cam I22 mounted on the main cam shaft 21 just behind the cam I03. The rod H5 is retracted and the cam follower I2I maintained against its associated cam by a. helical spring I23 which surrounds the rod and is compressed between the guide H6 and a stop member I24 secured to the rod.

In accordance with the invention, hangers are pressed from a relatively thin water pulp mixture and the excess water is forced out of the material during the pressing operation. This water escapes through apertures provided therefor in the ends of the plungers I4 and I3. These apertures are indicated at I and I3! in the plungers I4 and I3, respectively,-in Fig. 4. The apertures communicate at their rear ends with passages I32 and I33, respectively, formed in the respective plungers, which passages in turn c0m municate with elongated recesses I34 and I35 formed in the lower portions of the plungers adjacent the lower surfaces of the forms I2 and I I, respectively. The forms in turn have ports I36 and I37, respectively, communicating with the recesses I34 and I35, respectively. The ports I36 and I31 are connected by flexible hose connections I 38' and I39, respectively, with a Waste pipe I through which the excess water is discharged and used for preparing additional pulp mixture.

The construction of the main elements of the machine having now been described, the manner in which the difierent? elements cooperate will now be explained by following through the normal operation of the machine.

Referring to Figs. 4 and 9, both of which views are taken with the machine in the same position, it will be observed that the faces of the plungers I3 and I4 are equally spaced from a central plane, which plane is indicated by the broken line I50. The plungers are in their extreme outmost positions as indicated by the fact that the cam followers 39 and 40 are resting on the lowermost part of cam 33. In this position also the forms I I and I2 are in abutting relation, but their plane of intersection is positioned to the right of the center line I50, in which position the port 90 is uncovered by the plunger I4. In this position also the cam follower I02 is riding against the high part of cam I03, dis

placing the lever I00 and the rod 99 into lowermost position in which the valve 96 in the pulp reservoir 93 has disconnected the reservoir from the manifold 94 and has connected it to the manifold 89 for discharging pulp in the reservoir into the mold. In Fig. 9 the mold has been indicated as filled. The parts remain in the positions shown in Figs. 4 and 9 for only a short interval as by virtue of the air pressure delivered through pipe III! to the reservoir 93, the pulp charge in the latter is delivered very quickly to the mold.

The rotation of the cam shaft 21 out of the position shown in Fig. 4 permits the cam follower III2 to be retracted by the spring I04 to restore the valve 96 to normal position so that it is again communicated with the main pulp tank 95 through manifold 94 and begins to fill with pulp. The cam followers 39 and 40 ride on a concentric portion of the cam 33 for a short interval, maintaining the plungers I3 and I4 in the same positions, but the cams 32 and 34 controlling the forms II and I2 shift the latter in unison while still maintaining them in abutting relation so that they are moved into the position shown in Fig. 10 in which the juncture plane of the forms lies in the center plane I and the inlet port 90 in form I2 is carried. past the end of the plunger I 4, thereby closing the port.

During the preceding operations the arm III under the control of the cam follower I2I of the cam I22 was in elevated position clear of the coat hanger 3 as shown in Fig. 4. However, immediately following movement of the forms II and I2 to bring their juncture to the center line I50, the cam I22 shifts the arm III into lower position (shown in Fig. 2), in which the bifurcated tips of the arm straddle the hook 3 and remain in that position until the compression of the pulp has been completed and the forms and plungers separated.

20 The machine is now in condition to start the compression of the pulp in the mold and the cam 33 gradually forces the followers 39 and 40 downwardly to shift the connecting rods and IE0 upwardly thereby actuating the toggle links I4 and I9 and I4 and III to force the plungers I3 and I3 toward each other into the position shown in Fig. 11in which the pulp is fully compressed. Of course as the pulp mixture in the mold is compressed, the excess Water is discharged through the apertures I30, I3I in the plunger faces and through the passages I32, I33, the recesses I34 and I35 and the hose connections I38 and I39 to the waste water line I40. The pulp is compressed substantially to its limit of compressibility and during the final movement of the cam followers 39 and 40 and the levers 58 and 58', the springs 64 in the yieldable connecting rods 50 and. 60' compress slightly to allow for slight variations in the thickness of the compressed hanger, which variations might be caused by employing pulp mixtures of slightly different concentration with respect to the amount of water present. If yieldable means were not provided somewhere in the linkage and excess fiber were introduced into the mold, terrific forces would be created that might wreck the machine.

Although it is not absolutely necessary to provide the spring links 46 between the forms II and I2 and their actuating levers, these links are highly desirable as they make it possible to operate the machine without having the parts adjusted with great precision. Thus it will be obvious that if the entire linkage between the cam followers 31 and 3B and their associated plungers were unyieldable, it would be necessary to adjust the machine very accurately to just bring the ends of the forms II and I2 together. If the adjustment were such as to tend to move the forms II and I2 toward each other, even to only a slight extent after they had come in contact breakage of some portion of the link train would result.

Following movements of the plungers into in: nermost positions in which the pulp is fully compressed as shown in Fig. 11, continued movement of the cam shaft 27 and the cams thereon retracts the cam followers 31 and 38 to separate the forms I I and I2 as shown in Fig. 12. Thereafter the continued movement of the cams retracts the followers 39 and 40 to separate the plungers I3 and I4, this movement continuing until the plungers are in fully separated position as shown in Fig. 13.

and 13), so that despite any tendency of the compressed hanger to adhere to one or the other of the plunger faces, it is retained in central position by the arm III so that it is completely disengaged from the plungers and drops away from them out of the press. As the hanger drops out from between the plungers, it falls clear of the forms II and I2 onto a conveyer belt I55 supported upon pulleys I56 and I5! which travels continuously and carries the hanger out of the side of the machine where it is grasped by an operator and hung up to dry.. An idler pulley I51 is provided tokeep the under lap of the belt I55 clear of the worm wheel 30 and the belt is driven by pulley I51, which in turn isdriven by a belt indicated at I58 from the main shaft of the worm 3|.

As shown in Fig. 13, the plungers I3 and Il are fully retracted and the forms II and I2 are also retracted equal distances on opposite sides of the center line I50. Continued rotation of the cams leaves the plungers in their spaced apart positions, the followers 39 and 40 riding on concentric portions of the cam 33 and the form II likewise remains in the position shown in Fig. 13

by virtue of the fact that its associated follower 38 is riding on a concentric portion of the cam 34.

However, during the final rotation of the cams from the position corresponding to the form position shown in Fig. 13 to the starting. position shown in Fig. 9, the cam 31 rides onto a high part of its associated. cam 32, thereby forcing the form I2 to the right past the center line I50 into engagement with the form II in which the .inlet port is again open and the cycle completed.

It will be observed that a complete cycle of operation is completed during each revolution of the cam shaft 21 and the various movements described are readily obtained by merely suitably shaping the various cams.

In Fig. 4, which shows the machine at the beginning of the cycle described, the yieldable link 46' is shown compressed, whereas link 45 is not compressed. The tension of the yieldable links 46 and 46' is so adjusted that slight differences in the frictional resistance encountered by the two forms II and I2 determine to a large extent which of the links 46 and 46' will yield. In the position shown in Fig. 4 the form I2 has just beenmoved to the right, whereas form II has not been moved to the left since it was retracted. Therefore the frictional resistance encountered by the form I2 in moving past the plunger I4 and also the frictional resistance between plunger I3 and. form II tending to restrain the atter, link 46' yielded, whereas link 46 was displaced only slightly.

However, during the subsequent movement of the two forms to bring their juncture to the center line I50 (the position shown in Fig. 10), all of the moving force for moving both forms is applied through the link 46. Therefore, following movements of the formsinto the center position shown in Fig. 10, the yieldable link l6 will have yielded to a greater extent than the link 46'.

A most important feature of construction in the present machine is the design of the plunger faces which constitute the dies contacting andcompressing' the pulp. It has previously been indicated that these plunger-faces are traversed by numerous apertures I3I and I32 in the respective dies for the discharge of excess water from the mold. It is not new broadly to provide apertures in the plungers for the discharge of the water, but we believe it to be new to so position the apertures in the two dies that all of the apertures in one die are in staggered relation with respect to the apertures in the other die.

Thus, as shown in Fig. 14, the apertures I3I are staggered with respect to the apertures I30 and each aperturepositioned substantially symmetrically equidistant from the group of nearest apertures in the other die.

The apertures I30 and I3I in the plunger faces are preferably positioned approximately /8 of an inch apart and maybe about 5 of an inch in diameter. To prevent pulp being forced into the apertures and clogging them, and to prevent the loss ofpulp from the mold, the apertured faces of the plungers are perfectly covered .with a'relatively dense wire screen asshown in Fig. 7. The screen I60 is drawn over the face of the plunger and retained in place by clamping strips I 6| setin recesses provided therefor in the plunger edges and clamped in place by screws I62.

We have found it desirable in constructing pulp coat hangers to make the main cross members of the hangers in substantially I-beam cross-sectional shape as shown in Fig. 1'7. To this end the faces of the plungers I3 and I4 are slightly grooved or dished as indicated at I66 plicable for other-purposes and may be employed not only in pulp presses for shaping other articles than coat hangers, but in presses for handling materials other than pulp. The invention. is therefore. to be limited only as set forth in the appended claim.

We claim:

A press for molding articles from fibrous pulp comprising: a pair of hollow forms mounted on supports for selective sliding movement and having cooperating faces, timed power means actuating the forms to move and hold them together with the faces engaging to effect a substantially fluid-tight seal and defining a pressing chamber, a plunger in each form having a substantially fluid-tight sliding fit therein, a port in the upper part of one of said forms for the introduction of pulp into the chamber, means shifting the forms while held together and while the plungers are

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