US1805275A - Forming press - Google Patents

Forming press Download PDF

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US1805275A
US1805275A US1805275DA US1805275A US 1805275 A US1805275 A US 1805275A US 1805275D A US1805275D A US 1805275DA US 1805275 A US1805275 A US 1805275A
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platen
press
piston
mold
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C33/00Moulds or cores; Details thereof or accessories therefor
    • B29C33/30Mounting, exchanging or centering
    • B29C33/306Exchangeable mould parts, e.g. cassette moulds, mould inserts

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  • ' vMy invention relates to presses of the type known as forming presses, wherein an article is formed or shapedout of plastic material, and more particularly to a press for forming v, a plastic coating on a core of wood or other material, as in the manufacture of toilet seats and the like.
  • An object of my invention is to provide a press with a platen that is tiltable toward the operator, so as to facilitate the placing of i work thereon and withdrawal of the finished work.
  • a further object of my invention is to provide a press with selective devices for bringinga selected one of a plurality of dies into cooperative relation with an additional die which is shaped to act as a complement to each of the first mentioned dies.
  • a still further object of my invention is to -30 provide a press of the class described which will. be extremely simple in construction and operation and unusually rugged.
  • Fig. l is a side elevational View partly in section of a press embodying my invention
  • Fig. 2 is an elevationalview of the upper .30 part of such a press, taken at right angles to the view of Fig. 1, a pair of cooperating mold members being shown in positions occupiedin an initialforming operation.
  • Fig. 3 is'a sectional view taken on line 33 of Fig.1, showing mold parts in positions 0c; cupied in the final forming operation.
  • My improved press in its preferred embodiment, comprises a bed 1, on which a cylinder 2 is mounted having a pipe 3 connected at the bottom for the admission and withdrawal of fluid.
  • the cylinder has an outstanding flange 4 and is provided with a plurality of ears 5, each of which is secured to the lower end of a column 6.
  • a cross-head 7 is supported on the upper-ends of the columns.
  • a piston 8 Slidable within the cylinder is a piston 8 having on its upper end a tongue 9 (Fig. 2)
  • the block has a recess shaped to receive a fulcrum member 12 which is prevented from longitudinal movement by means of plates 13 secured to the sides of the block.
  • a platen let is carried by the fulcrum member and has a supporting portion resting thereon and shaped to conform to the surface thereof which is lubricated to facilitate the tilting of the platen.
  • a female mold member 15 shaped to conform to the surface of a toilet seat is demountably secured to the platen and has a pair of openings 16 therein each of which receives a plunger.
  • Each plunger has a head 17 and a stem 18, the latter being disposed adjacent a plate 20 (Fig. which is secured to a piston 21 slidable in a cylinder 22 on the platen.
  • a pipe 23 communicates with the cylinders for admitting fluid thereto.
  • the wide area of the plates ensures their engagement with the stems of the plungers even though the latter should be spaced closer together or farther apart than they are shown to be. It will therefore be apparent that instead of the mold illustrated, molds of other shapes may readily be substituted. 7
  • the platen has a pair of lugs 24 thereon which are engageable with and slidable along the two rear columns 6 and it also has a pair of downwardly and rearwardly extending arms 25 which are pivoted on a cross-bar 26.
  • a pair of sleeves 27 secured to the ends of the cross-bar are slidably mounted on the columns and are limited in their. downward movement by stops 28.
  • a rod 30 aflixed to the cross-bar extends through an opening in the flange 4 and has a nut 31 on its free end and a spring 32 compressed between the nut and the flange.
  • a slide 34 Inwardly projecting from the sides of the cross-head 7 are guides 33, on which a slide 34: is mounted for horizontal sliding movement. Brackets 35 on the upper face of the slide are secured to a rod 36 having thereon a double-acting piston 37 which is reciprocable within a cylinder 38.
  • the cylinder is supported above the cross-head by suitable means, such as clamps 40, and has an opening at each end for the admission or exhaust of fluid such as compressed air for actuating the piston.
  • the fluid is conducted to the cylinder by pipes 41 which communicate with a manual control valve 42.
  • a male mold member 43 which is the reverse of the female mold member 15, and which carries a centering head 44 and a centering pin 45 adapted to fit in openings 46 and 47 respectively in the female mold mem- 0 her.
  • the latter member carries stops 48 which are engageable with the body of the former, as shown in Fig. 2, to determine the space between the forming walls in the mold.
  • a female mold member 50 having the reverse shape of the bottom of a toilet seat is also demountably secured to the slide and has recesses 51 therein to receive the stops 48 so that the forming walls of the mold member 15 can be brought into engagement with the corresponding walls of the mold member 50.
  • the extreme positions of the slide are determined by stop-screws 52 which are threaded in the head 7 and are engageable with the brackets 35. In one of said positions the male mold member l?) is in vertical alignment with the platen while in the other, the female mold member 50 is so aligned.
  • the operation of the device in the forming of a toilet seat is as follows.
  • the platen 14 being tilted toward the operator, in the position shown in dotted lines in Fig. 1, ant the slide 34 being in the posit-ion shown in Fig. 2, a sheet 53 of unvulcanized rubber stock is placed over the female mold member 15 and hydraulic pressure is applied in the cylinder 2, forcing the piston 8 upwardly.
  • the block 11 and the fulcrum member 12 are carried upwardly and the platen rotates about the cross-bar 26 as a pivot, since the latter is prevented from rising by the downward pull -of the s ring 32 acting through the rod 30,
  • the platen is rocking on the fulcrum member and the block is being slid along the top of the piston, its movement being guided by the tongue 9.
  • the platen reaches a horizontal position, the lugs 24 abut against the rear column 6, thus preventing further pivotal movement, and the platen is then forced upwardly in the horizontal position until the stops 4:8 engage the male mold 43.
  • the stock is shaped in correspondence with the upper portion of a toilet seat.
  • the hydraulic pres sure is then released in the cylinder 2, and the iston sinks, the platen moves downwardly in the horizontal position until the sleeves 27 are arrested by the stops 28, after which it assumes the tilted position, reversing the movement described above.
  • a core 54 of a suitable substance, such as wood is then placed in the female mold member 15 over the molded rubber, and another sheet of rubber 55 is placed thereover. Fluid is then admitted to the proper opening in the cylinder 38, and the piston 37 is thus operated to move the slide 34 with the female mold men ber 15 directly over the platen 14.
  • the piston 8 is then moved upwardly in the manner described to cause the mold members to come into compressive relationship with each other. This step has the effect of molding the rubber firmly to the core and also of trimming oil the edges so that the article will present a neat and finished appearance.
  • the formed article is in condition to be withdrawn from the forming press.
  • my device may be used for the forming of various articles of plastic material, although it is especially adapted for the forming of a plastic coating on a core, and the structure is suitable, in fact, for any compressive operation.
  • a substantial rangeof equivalents is contemplated within the scope of the appended claims.
  • a movable platen In a press, a movable platen,a mold on said platen, a support, a plurality of additional molds shaped to act as com laments to the first mentioned mold and slide 1y mounted on said su ort, for substantiall strai lit 1 P gl 8' line movement, a cylinder, a den e-acting piston rigidly secured to said additional molds, recipl'ocable by fluid ressuie in said cylinder for sliding said additional molds on said support to align any selected one of them with the first mentioned mold, and means for moving said platen to compress-the aligned molds together.
  • a platen mounted for tilting and sliding movement, a member mounted above and in opposed relation to said platen, means for moving said platen upwardly from an inclined to substantially horizontal position and for continuing the upward movement of said platen into compressive relation with said member, and means for maintairb" ing said laten substantially horizontal in its continue upward movement.
  • a platen mounted for'tiltin and sliding movement, a member mounts above and 1n opposed relation to said platen,
  • a vertical guide and means for raising said platen from a forwardly tilted position to a substantially horizontal position and brin lot) ing said platen into engagement we guide and for further raisinv' said platen,tin-' til it engages said member, said guide being operative to prevent further tilting of said platen after it assumes a horizontal position.
  • a platen mounted for tilting and sliding movement, a member mounted in opposed relation to said platen, a piston, hydraulic means for raising said piston, a member slidably mounted on said piston, a fulcrum member carried by the slidable member and supporting said platen, means operable on the upward movement of said piston to cause said platen to assume a horizontal position, and means for guiding said platen and maintaining it horizontal in its continued upward movement into compressive relation to the first mentioned member.
  • a platen a member mounted in opposed relation to said platen, a member movable upwardly and downwardly in a vertical line, means for guiding the second mentioned member, the rear end of said platen being pivoted on said second mentioned member, a piston, hydraulic means for raising and lowering said piston, a member mounted for horizontal sliding movement on said piston, a fulcrum member carried by the third mentioned member and supporting the forward part of said platen for raising the same from a tilted position, means for preventing the upward movement of the rear end of said platen until the platen reaches a horizontal position and means operative when said platen reaches a horizontal position to maintain it horizontal in its continued upward movement into compressive relation with the first mentioned member.
  • a platen a member mounted in opposed relation to said platen, a member movable upwardly and downwardly in a vertical line, means for guiding the second mentioned member, the rear end of said platen being pivoted on said second mentioned member, means acting on said platen intermediately of its front and rear ends for raising and lowering the same, means including a spring for preventing said second mentioned member from moving upwardly when the first mentioned means is raising said platen from a forwardly tilted position, the second men tioned means being operative when said platen assumes a substantially horizontal position to permit compression of said spring and upward movement of the second mentioned member, and means operative to guide said platen and maintain it substantially horizontal in its continued upward movement into compressive relation with the first mentioned member.
  • a platen a member mounted in opposed relation to said platen, a member movable upwardly and downwardly in a vertical line, means for guiding the second mentioned member, the rear end of said platen being pivoted on said second mentioned member, means acting on said platen intermediately of its front and rear ends for raising and lowering the same, means including a spring for preventing said second mentioned member from moving upwardly when the first mentioned means is raising said platen from a forwardly tilted position, the second mentioned means being operative when said platen assumes a substantially horizontal position to permit compression of said spring and upward movement of the second mentioned member, means operative to guide said platen and maintain it substantially horizontal in its continued upward movement into compressive relation with the first mentioned member and a stop for limiting the downward movement of said second mentioned member, and thereby causing said platen to assume a tilted position in its downward movement.
  • a plurality of mold members and a tiltable and vertically movable platen for supporting one of said mold members, together with means for automatically shifting the platen from its tilted position to a horizontal position when forcing the same into compressive relation with a corresponding mold member, said means comprising a re siliently mounted shifting rod.

Description

May 12, 1931. .J. w. BISHOP FORMING PRESS Filed Jan. 27, 1928 3 Sheets-$heet l J. W. BISHOP FORMING PRESS May 12, 1931.
Filed Jan. 27, 1928 5 Sheets-Sheet 2 fizz/e720? May 12, 1931. J. w. BISHOP 9 3 FORMING FRESS Filed Jan. 27, 1928 3 Sheets-Sheet 5 Patented May 12, 1931 i: 7 UNITED STATES PATENT OFFICE JOSEPH W. BISHOP, OF MUSKEGON, MICHIGAN, ASSIGNOE TO THE BRUNSWICK-BALKE- COLLENDER COMPANY, OF CHICAGO, ILLINOIS, A CGRPORATION' OF DELAWARE FORMING PRESS Application filed January 27, 1928. Serial No. 249,843.
' vMy invention relates to presses of the type known as forming presses, wherein an article is formed or shapedout of plastic material, and more particularly to a press for forming v, a plastic coating on a core of wood or other material, as in the manufacture of toilet seats and the like.
An object of my invention is to provide a press with a platen that is tiltable toward the operator, so as to facilitate the placing of i work thereon and withdrawal of the finished work. 1
A further object of my invention is to provide a press with selective devices for bringinga selected one of a plurality of dies into cooperative relation with an additional die which is shaped to act as a complement to each of the first mentioned dies.
A still further object of my invention is to -30 provide a press of the class described which will. be extremely simple in construction and operation and unusually rugged.
Other objects and advantages will appear as the description proceeds.
.25 Referring now to the drawings forming a part of this specification:
Fig. lis a side elevational View partly in section of a press embodying my invention; Fig. 2 is an elevationalview of the upper .30 part of such a press, taken at right angles to the view of Fig. 1, a pair of cooperating mold members being shown in positions occupiedin an initialforming operation.
Fig. 3 is'a sectional view taken on line 33 of Fig.1, showing mold parts in positions 0c; cupied in the final forming operation.
. My improved press, in its preferred embodiment, comprises a bed 1, on which a cylinder 2 is mounted having a pipe 3 connected at the bottom for the admission and withdrawal of fluid.
The cylinder has an outstanding flange 4 and is provided with a plurality of ears 5, each of which is secured to the lower end of a column 6. A cross-head 7 is supported on the upper-ends of the columns.
. Slidable within the cylinder is a piston 8 having on its upper end a tongue 9 (Fig. 2)
whichfis received in a groove 10 in a sliding 5 b1ock .11 The block has a recess shaped to receive a fulcrum member 12 which is prevented from longitudinal movement by means of plates 13 secured to the sides of the block.
A platen let is carried by the fulcrum member and has a supporting portion resting thereon and shaped to conform to the surface thereof which is lubricated to facilitate the tilting of the platen.
A female mold member 15 shaped to conform to the surface of a toilet seat is demountably secured to the platen and has a pair of openings 16 therein each of which receives a plunger.
Each plunger has a head 17 and a stem 18, the latter being disposed adjacent a plate 20 (Fig. which is secured to a piston 21 slidable in a cylinder 22 on the platen. A pipe 23 communicates with the cylinders for admitting fluid thereto. The wide area of the plates ensures their engagement with the stems of the plungers even though the latter should be spaced closer together or farther apart than they are shown to be. It will therefore be apparent that instead of the mold illustrated, molds of other shapes may readily be substituted. 7
The platen has a pair of lugs 24 thereon which are engageable with and slidable along the two rear columns 6 and it also has a pair of downwardly and rearwardly extending arms 25 which are pivoted on a cross-bar 26. A pair of sleeves 27 secured to the ends of the cross-bar are slidably mounted on the columns and are limited in their. downward movement by stops 28. A rod 30 aflixed to the cross-bar extends through an opening in the flange 4 and has a nut 31 on its free end and a spring 32 compressed between the nut and the flange.
Inwardly projecting from the sides of the cross-head 7 are guides 33, on which a slide 34: is mounted for horizontal sliding movement. Brackets 35 on the upper face of the slide are secured to a rod 36 having thereon a double-acting piston 37 which is reciprocable within a cylinder 38. The cylinder is supported above the cross-head by suitable means, such as clamps 40, and has an opening at each end for the admission or exhaust of fluid such as compressed air for actuating the piston. The fluid is conducted to the cylinder by pipes 41 which communicate with a manual control valve 42.
Demountably supported on the under side of the slide is a male mold member 43 which is the reverse of the female mold member 15, and which carries a centering head 44 and a centering pin 45 adapted to fit in openings 46 and 47 respectively in the female mold mem- 0 her. The latter member carries stops 48 which are engageable with the body of the former, as shown in Fig. 2, to determine the space between the forming walls in the mold.
A female mold member 50 having the reverse shape of the bottom of a toilet seat is also demountably secured to the slide and has recesses 51 therein to receive the stops 48 so that the forming walls of the mold member 15 can be brought into engagement with the corresponding walls of the mold member 50. The extreme positions of the slide are determined by stop-screws 52 which are threaded in the head 7 and are engageable with the brackets 35. In one of said positions the male mold member l?) is in vertical alignment with the platen while in the other, the female mold member 50 is so aligned.
The operation of the device in the forming of a toilet seat is as follows. The platen 14 being tilted toward the operator, in the position shown in dotted lines in Fig. 1, ant the slide 34 being in the posit-ion shown in Fig. 2, a sheet 53 of unvulcanized rubber stock is placed over the female mold member 15 and hydraulic pressure is applied in the cylinder 2, forcing the piston 8 upwardly. The block 11 and the fulcrum member 12 are carried upwardly and the platen rotates about the cross-bar 26 as a pivot, since the latter is prevented from rising by the downward pull -of the s ring 32 acting through the rod 30,
and at t 10 same time the platen is rocking on the fulcrum member and the block is being slid along the top of the piston, its movement being guided by the tongue 9. lVhen the platen reaches a horizontal position, the lugs 24 abut against the rear column 6, thus preventing further pivotal movement, and the platen is then forced upwardly in the horizontal position until the stops 4:8 engage the male mold 43. In this operation the stock is shaped in correspondence with the upper portion of a toilet seat. The hydraulic pres sure is then released in the cylinder 2, and the iston sinks, the platen moves downwardly in the horizontal position until the sleeves 27 are arrested by the stops 28, after which it assumes the tilted position, reversing the movement described above. A core 54 of a suitable substance, such as wood is then placed in the female mold member 15 over the molded rubber, and another sheet of rubber 55 is placed thereover. Fluid is then admitted to the proper opening in the cylinder 38, and the piston 37 is thus operated to move the slide 34 with the female mold men ber 15 directly over the platen 14.
The piston 8 is then moved upwardly in the manner described to cause the mold members to come into compressive relationship with each other. This step has the effect of molding the rubber firmly to the core and also of trimming oil the edges so that the article will present a neat and finished appearance.
After the platen is again lowered, the formed article is in condition to be withdrawn from the forming press. This is accomplished by the ejecting means as follows. Fluid is admitted to the cylinder 22, thus forcing the pistons 21 and the discs 20 upwardly, lifting the ejecting lungers and raising the formed article slightly out of the mold, when it can easily be removed by hand. It is now ready to be placed in a suitable device for vulcanization.
It will be understood that many changes in the described embodiment may be made within the scope of my invention. For example, my device may be used for the forming of various articles of plastic material, although it is especially adapted for the forming of a plastic coating on a core, and the structure is suitable, in fact, for any compressive operation. A substantial rangeof equivalents is contemplated within the scope of the appended claims.
What I claim and desire to secure by Letters Patent is:
1. In a press, a movable platen,a mold on said platen, a support, a plurality of additional molds shaped to act as com laments to the first mentioned mold and slide 1y mounted on said su ort, for substantiall strai lit 1 P gl 8' line movement, a cylinder, a den e-acting piston rigidly secured to said additional molds, recipl'ocable by fluid ressuie in said cylinder for sliding said additional molds on said support to align any selected one of them with the first mentioned mold, and means for moving said platen to compress-the aligned molds together.
2. In a press, a platen mounted for tilting and sliding movement, a member mounted above and in opposed relation to said platen, means for moving said platen upwardly from an inclined to substantially horizontal position and for continuing the upward movement of said platen into compressive relation with said member, and means for maintairb" ing said laten substantially horizontal in its continue upward movement.
3. In a press, a platen mounted for'tiltin and sliding movement, a member mounts above and 1n opposed relation to said platen,
a vertical guide, and means for raising said platen from a forwardly tilted position to a substantially horizontal position and brin lot) ing said platen into engagement we guide and for further raisinv' said platen,tin-' til it engages said member, said guide being operative to prevent further tilting of said platen after it assumes a horizontal position.
4. In a press, a platen mounted for tilting and sliding movement, a member mounted in opposed relation to said platen, a piston, hydraulic means for raising said piston, a member slidably mounted on said piston, a fulcrum member carried by the slidable member and supporting said platen, means operable on the upward movement of said piston to cause said platen to assume a horizontal position, and means for guiding said platen and maintaining it horizontal in its continued upward movement into compressive relation to the first mentioned member.
5. In a press, a platen, a member mounted in opposed relation to said platen, a member movable upwardly and downwardly in a vertical line, means for guiding the second mentioned member, the rear end of said platen being pivoted on said second mentioned member, a piston, hydraulic means for raising and lowering said piston, a member mounted for horizontal sliding movement on said piston, a fulcrum member carried by the third mentioned member and supporting the forward part of said platen for raising the same from a tilted position, means for preventing the upward movement of the rear end of said platen until the platen reaches a horizontal position and means operative when said platen reaches a horizontal position to maintain it horizontal in its continued upward movement into compressive relation with the first mentioned member.
6. In a press, a platen, a member mounted in opposed relation to said platen, a member movable upwardly and downwardly in a vertical line, means for guiding the second mentioned member, the rear end of said platen being pivoted on said second mentioned member, means acting on said platen intermediately of its front and rear ends for raising and lowering the same, means including a spring for preventing said second mentioned member from moving upwardly when the first mentioned means is raising said platen from a forwardly tilted position, the second men tioned means being operative when said platen assumes a substantially horizontal position to permit compression of said spring and upward movement of the second mentioned member, and means operative to guide said platen and maintain it substantially horizontal in its continued upward movement into compressive relation with the first mentioned member.
7. In a press, a platen, a member mounted in opposed relation to said platen, a member movable upwardly and downwardly in a vertical line, means for guiding the second mentioned member, the rear end of said platen being pivoted on said second mentioned member, means acting on said platen intermediately of its front and rear ends for raising and lowering the same, means including a spring for preventing said second mentioned member from moving upwardly when the first mentioned means is raising said platen from a forwardly tilted position, the second mentioned means being operative when said platen assumes a substantially horizontal position to permit compression of said spring and upward movement of the second mentioned member, means operative to guide said platen and maintain it substantially horizontal in its continued upward movement into compressive relation with the first mentioned member and a stop for limiting the downward movement of said second mentioned member, and thereby causing said platen to assume a tilted position in its downward movement.
8. In a press, a plurality of mold members, and a tiltable and vertically movable platen for supporting one of said mold members, together with means for automatically shifting the platen from its tilted position to a horizontal position when forcing the same into compressive relation with a corresponding mold member, said means comprising a re siliently mounted shifting rod.
JOSEPH W. BISHOP.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2475693A (en) * 1947-01-16 1949-07-12 Borzym Alexander Power press
US2812543A (en) * 1955-04-12 1957-11-12 French Oil Mill Machinery Swinging head presses
US3096541A (en) * 1958-09-11 1963-07-09 Goodyear Tire & Rubber Apparatus for molding a valve receiving aperture in a tire

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2475693A (en) * 1947-01-16 1949-07-12 Borzym Alexander Power press
US2812543A (en) * 1955-04-12 1957-11-12 French Oil Mill Machinery Swinging head presses
US3096541A (en) * 1958-09-11 1963-07-09 Goodyear Tire & Rubber Apparatus for molding a valve receiving aperture in a tire

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