US3031780A - Folding machines - Google Patents

Description

y 1962 G. I. FREDHOLM 3,031,780

FOLDING MACHINES Filed April 6. 1959 5 Sheets-Sheet 1 May 1, 1962 e. 1. FREDHOLM FOLDING MACHINES 5 Sheets-Sheet 2 Filed April 6, 1959 lizz v ezzdivr I.F1d)1?/O 6122/ May 1, 1962 G. I. FREDHOLM 3,031,780

FOLDING MACHINES Filed April 6, 1959 5 Sheets-Sheet 5 May 1, 1962 G. 1. FREDHOLM 3,031,780

FOLDING MACHINES Filed April 6, 1959 5 Sheets-Sheet 4 7 Fig.10

May 1, 1962 G. 1. FREDHOLM 3,031,780

FOLDING MACHINES Filed April 6. 1959 5 Sheets-Sheet 5 Fig. 11

United rates if r 3,931,?39 Fatented May 1, 1962 3,931,78tl FQLDING MACHDIES Gunnar Ivar Fredholm, Forfattarvagen 44, Bromma, Sweden Filed Apr. 6, 1959, Ser. No. 804,422 Claims priority, application Sweden July 19, 1958 1 Claim. (Cl. 38-2) This invention relates to folding machines such as are used for folding flatwork in laundries, particularly sheets, table cloths and the like preferably after the ironing of such articles of fiatwork.

The object of the present invention is to provide an improved machine utilizing a single reciprocating folding blade, which machine requires a minimum of space and is arranged as a unit built into an ironing machine.

A further object is to provide a device for measuring the length of the fiatwork during that period said work being passed through the ironing machine, so that no additional space is required for the measuring track.

A further object is to provide an improved timing device for the folding mechanism comprising individually working units which may be started by means of impulses delivered by the measuring device, so that one article can be measured during the period in which another article has arrived to the folding device or is being folded.

Further objects of the invention in part are obvious and in part will appear more in detail hereinafter.

in the drawings,

FIGS. 1 to 5 are diagrammatic views showing the several steps in the folding operation;

FIG. 6 is a perspective view of two timing members for delivering of impulses to the folding blade mechanisrn;

FIG. 7 is a diagrammatic side elevation illustrating a part of an ironing machine provided with the folding device according to the invention;

FIG. 8 is a plan view on an enlarged scale of the folding blade and of one of the two appertaining folding rollers;

FIG. 9 is a side view, partly in section, of the timing device which contains three speed controlling units;

FIG. 10 is a sectional elevation of the timing device, the section being taken on line 101(l, FIG. 9;

FIG. 11 is a diagrammatic view showing the driving members of the folding blade and the electric wire diagram connected thereto.

The folding operation will be principally explained, reference being made to FIGS. 1 to 6.

In FIG. 1 a conventional fiatwork ironer is shown, including the usual heated platen or chest 1 with which co-operate padded rollers. The last roller of the ironer is shown in dot-dash lines and designated by 2. The roller co-operates with the part 3 of the chest arranged at the delivery end of the ironing machine. From this end the calendered articles are directly fed into the folding device. in the FIGURE 1 the letter A represents the path which one edge of e.g. a bed sheet performs in the ironing machine. B represents the path which the fore edge of the bed sheet performs until the rear edge of the sheet arrives at the input end of the machine. Said distances may of course be measured from a chosen point of the track. At the point where the measuring operation is commenced feeling members are arranged. According to the example shown a row of contacts are used which are caused to break their circuit when the sheet passes. The circuit is then closed when the rear edge of the sheet has passed the contacts. The heated platen 1 is aranged as a fixed contact, the movable contact being formed as a spring normally engaging the platen and so arranged that the sheet may pass the row of contacts .without resistance.

In FIG. 2 is shown an arm 4 pivoted at 5 upon a fixed axis and at its end provided with a folding blade 6 which in known manner co-operates with folding rollers 8 and 9 as shown in FIG. 5. In FIG. 2 the folding arm 4 is shown in a middle position and the advancing edge of the sheet is hanging freely downward from the rear edge 7 of the chest 3. After one-fourth of the length of the sheet has passed over the edge 7 the folding arm takes the position .shown in FIG. 3 in which the blade 6 is pressed against the sheet at the edge 7 and causes the sheet to be draped over the folding blade as illustrated in FIG. 4. At the time when only one-fourth of the sheet remains in the chest the folding arm takes the position shown in FIG. 5 in which the folded sheet is fed into the bite of the two folding rollers 8 and 9. The sheet is thereafter in known manner engaged by the rollers and pulled free from the blade and is delivered on the far side of the rollers in a double fold condition.

The length of the sheet has according to the invention been measured during the ironing operation and electric impulses has been delivered when the advancing and the rear edges of the sheet have passed the: feeling contacts. The appertaining circuit is connected to low tension, eg 25 volt DC. The impulses from the feeling contacts are delivered over relay circuits to the timing device for the folding arm mechanism. Said device and mechanism operate synchronously with the driving shaft of the ironing machine.

The lengths A and B may be proposed to correspond to A and B revolutions of the driving-shaft of the ironer. The timing device is so performed that the folding arm 4 is moved into the first operative position, shown in FIG. 3, when the fore edge of the bed sheet has passed a distance corresponding to (A-l-B+ AB) revolutions of the driving-shaft of the ironer. When the folding arm 4 under the control of the timing device is caused to take the second operative position, shown in FIG. 5, the bed sheet has advanced a distance corresponding to revolutions of the driving-shaft. The described cyclical motions of the folding arm is obtained by means of an auxiliary shaft 19, shown in FIG. 6, which is adapted to complete one single revolution while the driving-shaft performs A revolutions. The shaft 10 is provided with cam members 11 and 12, arranged to actuate electric contact members 13 and M respectively, said contact members being thereby caused to close their circuits. Now supposing that the shaft 10 rotates clockwise and the cam members 11 and 12 can be set in such angular positions that the cam 11 has to perform a distance up to the contact 13 corresponding to (AB+%.B) of one revolution and the cam 12 has to nun a distance up to the contact 14 corresponding to (AB-}-%B). The cam 11 determines the point when the folding arm 4 is to be set into the first operative position and the cam 12 the point for the second operative position. The shaft 10 will be started in the moment in which the rear edge of the bed sheet passes the row of feeling contacts.

The measuring of the length of the sheet is obtained through the displacement of the cams 11 and 12 from a fixed starting position. Thereafter current impulses, obtained at the contacts 13 and 14, control the timing device during the folding operation so that in a first stage one quarter and in a second stage three-quarters of the length of the sheet have passed the delivery edge 7 of the chest.

The timing device will in such a case be occupied during that period the fore edge of the sheet actuates the feeling contacts until the folding arm has performed its second stroke. In order to avoid waste of time, due to the fact that the sheets are to be fed to the ironer at intervals corresponding to 2A revolutions of the driving shaft, the timing device may be provided with two or more individually working units. According to the example shown, three such units are connected to a selector arrangement adapted to deliver current impulses to the timing units in turn. The number of the timing units is on the one hand dependent on the length of the track A and on'the other hand on the length of the sheet.

FIG. 7 illustrates a part of an ironer machine provided with a supporting standard carrying chests 16 and rollers 17. At the inlet between the first roller 17 and the appertaining chest 16, a cross bar 18 carries a set of yielding contact springs or feelers 19 normally engaging the chest. The contact springs'or feelers are included in a circuit for transmitting impulses to the timing device.

When the sheet passes the feelers the impulse circuit is opened. Said circuit contains a steady current controlled relay as will be more closely described in connection with a wire diagram. When the sheet leaves the ironer it slides over the rear edge of the last chest 16 and is received by a conveyor band 20 passing over the two rollers 21 and 22 which are journaled in the end frame of the machine.

Said conveyor band delivers the sheet to the folding mechanism in which a folding lever 23, corresponding to the arm 4 as shown in FIGS. 2 to 5, is provided with a knife-shaped folding blade 24. The folding 'blade is so arranged that it can be moved into a position below the roller 22, as shown in FIG. 7, i.e. into a first operative position. In the second operative position the folding blade co-operates with a pair of folding rollers 25 and 26, of which the lower roller 26 is provided with a number of conveyer bands 27 running over a roller 23. The last named conveyer bands deliver the mangled and folded sheet.

The conveyor bands 27 are driven by means of a chain- 'wheel 29 mounted on the roller 23, a chain 30 that encircles both chain-wheel 29, and a chain-wheel 31. On the shaft of the wheel 31 further four chain-wheels are mounted viz. two wheels 31 with the same diameter as the first named and two wheels 32 with a greater diameter. 'One of the'two wheels 32 is, by means of a chain 33, in driving connection with a chain-wheel 34 fixedly connected to the conveyer roller 22. The other of the two wheels 32 is driven by a chain-wheel 36, by means of a chain 35, the chain-wheel 36 being mounted on the same shaft as a gear-wheel 37 which engages a gear-wheel 38 mounted on a stub shaft of the last ironing roller 17. The ironing rollers are in known manner driven by means of a motor (not shown).

By means of a chain 39 and a wheel 40 one of the Wheels 31 is arranged to drive a shaft 41, when an electromagnetic controlled jaw clutch is actuated, as will be described in connection with FIGS. 9 and 11. The shaft 41 carries a cam 42 which is adapted to move the folding lever 23 into its operative positions corresponding to thepositions of the arm 4 in FIGS 4 and 5. The lever 23 is pivoted at 43 on the machine frame and its lower portion 44 engages the cam 42 under the action of a spring 45, the fixed end of which is designated by 46. The

remaining chain wheel 31 drives, by the aid of a chain 47, a double sprocket 48, 49 the smaller sprocket 49 of the double sprocket being connected by a chain 50 with a sprocket 51. The shaft of this last named sprocket carries a gear wheel 52 meshing with three'gear wheels '53 to 55 which are arranged as planet wheels. Thus the sleeves 75 and 76 of which the first named is internally provided with a ring 77 forming bearing for a shaft 78 and the second sleeve surrounds a hollow shaft 79. In the hollow shaft a solid shaft 80 is journaled. Each of the shafts 79 and 8% is at its outer end provided with a radially directed cam arm 81 and 82 respectively adapted to engage an axially displaceable rid 83 arranged to actuate a microswitch 84. This switch controls a half-revolution clutch mechanism driving the cam 42 for the folding lever 23.

By means of a planetary gear the shaft 78 is in driving connection with the holiow shaft 79 as well as the solid shaft 80.

A gear wheel 85 of said plmetary gear is mounted on the inner end of shaft '78 and arranged to mesh with a planet wheel 86. This wheel is connected with two further planet wheels 87 and 88 and together with these wheels arranged rotatable on a common axle-journal 89 fastened into the one shank of the U-shaped crank 72. The gear wheels 85 and 86 have the same diameter so that the gear ratio is 1:1. The wheel 87 meshes with a gear wheel 90 fixedly connected with the solid shaft 80. The wheel 88 drives a wheel 91 on the hollow shaft 79, the gear ratio being 3:4. The wheel 91 is fixed to the last named shaft so that said shaft runs with a gear ratio 3:4, the gear ratio between the wheels 87 and 90 and thus the shaft 80 being 1:4. Said gear conditions correspond with the desired periods for setting of the folding blade into the operative positions, i.e. in a first moment when one-fourth of the length of the sheet has passed over the folding blade 24 and in a second moment when threequarters of the sheet has passed the blade.

The shaft 78 carries a ratchet 92 fixed to the gear wheel 85 and on said shaft. The ratchet 92 and thus the shaft 78 and the planet wheels can rotate in relation to the U- shaped crank 72, whereby a helical spring 93 is set. The inner end of said spring is fixed in a slot of the shaft 78 and the outer end 95 of the spring is connected with a pin inserted into the crank 72. Under the action of the helical spring a joggle 96 on the ratchet 92 engages a pin 97 inserted into the crank 72. In a plane parallel with the shanks of the U-shaped crank 72 and parallel with the ratchet 92 a latch lever 99 is journaled on a'pin 98 inserted in the crank 72. The one end of the latch lever is formed as a catch 100 normally engaging a recess 101 in the cylindrical inner surface 102 of the casing 71. The latch lever is actuated by a spring 103 which maintains the lever in engagement withsaid recess 101 so that the U-shaped crank is prevented to rotate in relation to the casing. The latch lever carries a pawl 104 journaled on a pin 105 fixed on the latch lever and swingable outwardly in relation to the centre of the ratchet against the action of a spring 106 which maintains the pawl in a position fixed by means of a slot and pin arrangement so that the pawl 104 only can engage the ratchet when the latch lever 99 disengages the recess 101. The teeth of the ratchet are so directed that the ratchet can be turned in the direction marked by an arrow 107 and is prevented to turn in the opposite direction. When the catch 10% is in engagement with the recess 101 the catch actuates, by means ofa rod108, a micro-switch 109 maintaining the same in. open position. The switch will, however, close its circuit when the latch lever 99 is actuated by a rod 110 in such a manner that the catch 100 disengages the rod 108. The rod 110 is actuated by a movable armature 111 of an electromagnet 112. When this electromagnet is alive the latch lever 99 is held in a position which permits the catch 100 to move on the cylindrical surface 102. Thus the U-shaped crank 72 is allowed to rotate in relation to the casing 71. In this position of the latch lever the pawl 104 engages the ratchet. The rod 110 is actuated by a spring which tends to displace the rod outwardly out of engagement with the latch lever and tends to bring the armature 111 into its rest position. As long as the electromagnet is alive the inner end of the rod 110 is maintained inside the cylindrical surface 162 so that said end is able to engage a notch 114 on the outer edge of the latch lever. In this way the crank 72 is maintained in the starting position when the electromagnet is energized.

The main shaft 78 of the planet gear is driven by means of an electromagnet controlled jaw clutch, the one member 115 of which being fixed on the shaft 78 and the other member 116 being axially displaceable on a shaft 117 and journaled on that shaft by means of a ball-bearing 118. The inner end of the shaft 117 is journaled in a bore centrally arranged in the clutch member 115 and the other end of said shaft is journaled in a ball-bearing 119, the outer race of which is fixedly mounted in the casing 71. The shaft 117 is axially displaceable in the bearing 119 and actuated by a spring 129 which tends to disengage the clutch. An armature 122 of an electromagnet 121 is, by means of a rod 123, arranged to let in the clutch.

The movable clutch member 116 forms part of a hub portion of the gear wheels 53 shown in FIGS. 7 and 9. The two gear wheels 54 and 55 are each arranged to drive a timing mechanism 71a and 71b respectively (FIG. 10).

The three timing units 71, 71a and 71b are arranged to be started in turn by means of a selector device which will be described below.

Referring particularly to FIG. 11 and electromagnet 125 is arranged to control a switch 126. The electromagnet is connected up in the circuit of the contact springs 19. When said circuit is closed the electromagnet maintains the switch 126 in open position. In the moment the sheet engages the springs 19 the circuit is broken and the switch 126 is closed. Thereby one of the three electromagnets 112 is energized. These electromagnets are connected to a selector provided with a contact arm 130 fixed on a driven shaft 131 and co-operating with three fixed contacts 132 to 134 angularly displaced 120 and each connected to one of the electromagnets 112. The selector arm 130 is driven by a stepping mechanism comprising a ratchet wheel 135 driven by a pawl 136 on an operating lever 138 which is arranged to be attracted by an electromagnet 137 against the action of a spring 139. When the electromagnet collapses the spring turns the lever 138 and the ratchet wheel 135 an angle of 120, the selector arm 130 being moved from one contact to the next of the contacts 132 to 134. The selector arm 13!) and the electromagnet 137 are coupled to the switch 126 in parallel.

When one of the electromagnets 112 is energized the armature 111 of said electromagnet turns the latch lever 99 such an angle that the microswitch 109 is permitted to close its circuit (FIGS. 9 to 11). Owing to this the electromagnet 121 is energized and moves the driving clutch member 116 into engagement with the clutch member 115 which thereby is rotated, one of the two cam arms 81, 82 being brought to actuate the microswitch 84 which delivers a current impulse to an electromagnet 146. The armature 141 of the electromagnet is connected with a wedge shaped latch 142 which, under spring action, engages a recess 143 of a turnable circular disc 144. Said disc has two diametrically opposed recesses 143 and serves as a half-revolution clutch for the shaft 41 carrying the cam 42 in the folding mechanism. The latch 142 is arranged to actuate a switch 145. When the electromagnet 140 is energized the latch 142- is disengaged closing the switch 145 and thereby connecting up an electro magnet 147 into a circuit 146 which is energized with the terminal voltage. The armature of the electromagnet 147 causes a jaw clutch 148 to be engaged so that the shaft 41 and thus the cam 42 are put in driving connection with a shaft 149 which in turn is driven by the chain wheel 40. This driving means may be performed fundamentally in the same manner as the jaw clutch 115, 116 controlled by electromagnet 121.

Because the current impulses from the microswitch 84 6 are short, due to the continuous motion of the cam arms 81 and 82, the armature 141, after a momentary attraction, must be retained in the attracted position by other means. According to the example shown this is obtained by that the recess 143 has such a depth and the wedge shaped latch has such a length that the latch after the disengagement slides on the edge of the circular disc 144 which at this moment has been set in motion by the engaged jaw clutch 148. Thereby the switch 145 is maintained in closed position until the latch 142 engages the next recess 143. The disc 144 in this manner is permitted to run half a revolution in order to set the folding blade into one of its operative positions.

The timing mechanism herein described operates as follows:

When the contact springs 19, shown in FIG. 7, are caused to break the impulse circuit, which occurs when the advancing edge of the sheet engages the springs 19, the switch 126 is closed as marked by dotted lines in FIG. 11. The electromagnet 112 will now be energized so that the electromagnet 121 is put in circuit by means of the microswitch 109. The jaw clutch 115, 116, shown in FIG. 9, is engaged and the shaft 78 is caused to rotate at a speed of one revolution for each A revolution of the driving shaft 124. The rod 110 is by means of the electromagnet 112 maintained in locking engagement with the notch 114 of the latching lever 99 as shown in FIG. 10. Hereby the crank 72 is prevented from rotating in relation to the casing 71. By means of the gear wheels 85, 86, 87 and 90 the shaft 78 drives the cam arm 82 at a speed of of that of the shaft 7 8. By means of the gear wheels 85, 86, 88 and 91 the cam arm 81 is rotated in the same direction as the first named cam arm and at a speed of A of that of the shaft 78. The helical spring 93, connecting the ratchet wheel 92 and the crank 72, is stretched.

In the moment the sheet has passed the contact springs 19 the switch 126 is caused to break the circuit. The electromagnet 112 now is currentless and the rod is, by means of its spring 113, brought out of engagement with the notch 114. The pawl 1114 engages the ratchet wheel 92 so that the helical spring 93 is prevented to turn the crank 72 in the direction marked by the arrow 107 in FIG. 10. Therefore the crank 72, with. its gear wheels mutually blocked, rotates at the speed of the shaft 78, the latch 100 sliding along the cylindrical surface 102.

In the moment in which the cam arm. 82 actuates the microswitch 84 the remaining part of the track for said cam arm corresponds to (A B+%B)=(A-%B) of one complete revolution. The microswitch 34 delivers at this time a current impulse to the electromagnet (FIG. 11) which brings the switch into closed position. The half-revolution disc 144 is started so that the folding blade is brought into its first operative position, shown in FIG. 7. This position corresponds to the blade position shown in FIGS. 3 and 4.

In the moment the latch lever 99 and thus the crank 72 are released by the rod 110 the remaining part of the track for the cam arm 81 corresponds to The cam arm 81 engages momentarily the microswitch 84 and the disc 144 (FIG. 11) is released and rotates the next half-turns causing the folding blade to take its second operative position in which the blade will force the sheet into the bite of the two folding rollers 25 and 26. Said second position of the folding blade is marked in FIG. 7 by dash-dotted lines and corresponds to the position shown in FIG. 5.

When the crank 72 has been turned one complete revolution the latch 100 of the latch lever engages, under the action of the spring 103 (FIG. 10), the rod 108 and the microswitch 109 breaks the circuit. The system is now currentless and the jaw clutch 115, 116 is under the action of the spring 129 disengaged. When the latch lever 7 returns into its starting position the pawl 164 is brought out of engagement with the ratchet Wheel 92. Thus the helical spring 93 is free to return the gear wheels of the crank 71.. into the starting position, i.e. the position deter mined by the joggle 96 of the ratchet Wheel and the pin 97 of crank 72.

The timingunit 71 is now ready to receive impulses from the contact springs 19. Meanwhile the two other timing units 71a and 7L; have been working in turn under control of. the selector device including elements numbered 31? to 134, inclusive. It will be noted that the switch 126 is maintained in closed position during that time the sheet is passing the contact springs 19. When these springs again contact the chest the electrical system is currentless. As soon as the next sheet engages said springs the selector arm 13% is advanced one step coupling up the next timing unit into the circuit shown in FIG. 11, so that one sheet can be measured during the period in which another sheet is passing the folding device.

It is obvious that many modifications may be made in the arrangement of the various parts of the machine and that in particular it is not limited to the production of a double fold sheet. In addition it also should be mentioned that the cam 42 of the folding mechanism may be rotated intermittently by any suitable half revolution mechanism controlled by the electromagnet 140.

What I claim is:

A combination ironing and folding machine comprising means to iron flatwork including at least one ironing roller and at least one chest cooperating with said roller, a horizontal discharge roller adjacent the discharge side of said chest, a pair of folding rollers parallel to and slightly below said discharge roller, said folding rollers being spaced horizontally from said discharge roller .a distance to permit flatwork discharged from said discharge rollcr to hangdown between said discharge roller and said pair of folding rollers, a horizontally movable folding blade movable back and forth across the horizontal space between the discharge roller and the folding rollers from a position immediately below said discharge roller toa position to insert flatwork between said folding rollers, means to move said blade, a timing mechanism including feelers in the path of fiatwork above said chest at the end of said chest remote from said discharge roller so as to engage said chest or engage said flatwork as it passes through the ironer, said timing mechanism being arranged to activate said means to move said blade from the position to insert fiatwork between the folding rollers to its position under the discharge roller when substantially a quarter of the length of a piece of flatwork has passed the level of said folding blade, and to move said blade from its position under said discharge roller to its position to insert flatwork in said folding rollers when an additional half of the length of said fiatwork has passed the level of said folding blade.

References Cited in the file of this patent UNITED STATES PATENTS 1,766,789 Mayer -h June 24, 1930 2,318,252 Myers May 4, 1943 2,330,977 Johnson Oct. 5, 1943 2,374,779 Preston May I, 1945 2,464,823 Malott Mar. 20, 1949 2,643,879 Spreckelmeier June 30, 1953 2,759,726 Sommerhalter Aug. 21, 1956

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