US2438787A - Paper bag making machinery - Google Patents

Description

March 30, 1948. J. NICHOLAS 2,438,787

PAPER BAG MAKING MACHINERY Filed May 23, 1944 8 Sheets-Sheet 1 jz vvi/v 70/!" Jon/1 M'uloursm" ror wfy.

March 1948. J. NICHOLAS 2,438,787

PAPER BAG MAKING MACHINERY Filedlay 23, 1944 8 Sheets-Sheet 2 March 30, 1948. J. NICHOLAS 2,438,737

PAPER BAG MAKING MACHINERY Filed May 23, 1944 a Sheets-Sheet s 5,, im W March 30, 1948. J. NICHOLAS 2,438,787

PAPER BAG MAKING MACHINERY Filed May 23, 1944 8 Sheets-Sheet 4 HTTO/FIVE J. NICHOLAS PAPER BAG MAKING MACHINERY March '30, 1948.

Filed May 25, 1944 8 Sheets-Sheet 5 m w 1.] m m .N c

j m w Q J HTTO/F/YEY- March 30, 1948. NICHOLAS 2,438,787

PAPER BAG MAKING MACHINERY Filed May 23, 1944 B Sheets-Sheet 6 ZvvmvTo/r- JO/l/V/V/Cf/OLHS.

FTTO/IIVE).

March 30, 1948. J. NICHOLAS 2,438,737

PAPER BAG MAKING MACHINERY Filed May 23, 1944 8 Sheets-Sheet 7 March 30, 1948. J. NICHOLAS 2,438,787

v PAPER BAG MAKING MACHINERY Filed May 23, 1944 8 Sheets-She et 8 mvm'rom JOHN mcuous Patented Mar. 30,194

PAPER BAG MAKING MACHINERY John Nicholas, Bristol, England, assignor to E. S. & A. Robinson, Limited, Bristol, England, a company of Great Britain Application my 23,1944, Serial No. 536,922- In Great Britain July 27, 1943 Claims. 1

which may be a paste box. These difiiculties are due to inequalities in the paper and to indifferent winding. Their effect is to cause the paper to wander laterally on the former plate from time to time, sometimes causing the paste line to leave the web altogether or to appear too far inside the paper tube, depositing paste on the former plate and/or on the inside of the bag. In order'to minimise this trouble it has hitherto been the practice to allow-a liberal amount of paper for an overlap and to depend on the vigilance of the operator. Attempts have been made to control the position of the web of paper in its relationship to the former plate and the seam adhesive device, but owing to the reel being too remote from the tubing point they have failed to reduce the difficulties substantially.

The object of the present invention is to provide means for overcoming the difficulties mentioned.

Paper bag making machinery according to the present invention is characterised in that the seam adhesive device is movable laterally of the direction of travel of the web and its movement in one lateral direction or another is controlled by the lateral movement of the paper web in such manner that the respective movements of the web and the seam adhesive device are substantially simultaneous and in the same direction so that they move together step-by-step.

The accompanying drawings illustrate various forms of the invention, and therein:

Fig. 1 is a front elevation of one form of the invention, and

Fig. 2 is a corresponding end elevation,

Figs. 3 and 4 are, respectively, a front elevation and an end elevation of a modified form of the invention.

Figs. 5 and 6 are, respectively, a front e1evation, and a diagrammatic view of associated mechanism, of another modified form of the invention.

Fig. 7 is an elevation of a further modified form of the invention, part of the mechanism being shown diagrammatically.

Fig. 8 shows, diagrammatically, the mechanism associated with the device shown in Fig. 7.

Figs. 9 and 10 are, respectively, a front elevation and an end elevation of a still further modi- 2 fled form of the invention, part of the mechanism being shown diagrammatically.

Fig. 11 represents a wiring diagram suitable for use with the form of the invention shown in Figs. v1 and 2.

In the form of apparatus illustrated in Figs. 1 and 2 the seam adhesive device l0, hereinafter referred to as the paste box, comprises a box or dish ll provided with bearings i2 on each end in which a spindle I3 is journalled. A pasting wheel i4 is mounted on the spindle l3 and its rim is adapted to depend into paste or other adhesive contained in the box II and on rotation apply said adhesive to paper with which it is adapted to make contact. The paste box I l is provided at one end with a fork l5 adapted to rest on a sleeve l6, and at the other end with two forks 29 also adapted to rest on the sleeve it between which and secured thereto is a .collar I! mounted on the sleeve l8 and adapted to be moved alon said sleeve l8 and-be secured thereto in any desired position by a screw stud l8; thereby the paste box It) is rigidly mounted on the sleeve IS; the position of the paste box ill on the sleeve l6 may be adjusted as desired by sliding the collar l1 along the sleeve IS. The sleeve 46 is internally screwthreaded and is disposed on and adapted to engage an externally screw-threaded horizontal shaft I 9 whereby the sleeve It will move along the shaft l9 when the said shaft is rotated. The shaft I9 is journalled in a frame 20 and is provided on one end with a worm wheel 2| which is engaged by a worm 22 on the shaft 21 of a motor 28; the motor 28 isadapted to rotate in either direction, controlled as hereinafter described, whereby the shaft l9 may be rotated in either direction.

A bracket 30 is also mounted on the'sleeve l6 by means of a collar 3! thereon which is adapted to slide on a key'32 along the sleeve l6 so that it may be disposed in any desired position along the sleeve 16 relative to the paste box III; the collar 3| is secured to the sleeve 16 by stud 33. The bracket 30 comprises a pillar 34 and a guide arm 35 provided with a bearing 36 adapted to engage and slide along a guide rod 31 which is parallel to the shaft IS. The engagement of the bracket 30 with the guide rod 31, through the guide arm 35, and with the sleeve It prevents the sleeve rotating. Two arms 38, 39 are pivotally mounted on the upper end of the pillar .34, the outer ends of each of said arms being provided with rotatable electric'contact members 40, M. The arms 38, 39 areadapted to be drawn towards each other by a spring 42. The contact members 88,

4| are metallic and are in the form of wheels having a comparatively thin tread, for example, a knife-edge; they may be metallic brushes. Each of the contact members 40, 4| is connected by separate electric leads to the starting devicev of the electric motor 28, and they are preferably insulated from the arms 38, 39 on which they are mounted. The two contact members 40, 4| are adapted to make contact with a metallic roller 43, around which the paper web 44 is passed, in adjacent planes laterally of the said roller as shown in Fig. 2, one contact member 4| making contact with the roller 43 at a position slightly nearer to one end of the roller 43 than the position at which the other contact member 40 makes contact with the roller; the axis of the roller 43 is also disposed at right angles to the direction of travel of the paper web 44 andparallel to the axis of the shaft I9. The roller 43 is Journalled in the frame 20. The contact members 40, 4| are pressed into contact with the roller 43 by the spring 42.

When the paper web 44 has been passed around the roller 43 the positions of the paste box I and of the bracket 30 are adjusted on the sleeve I6 so that the pasting wheel I4 makes contact with the web at the desired position, the contact member 40 makes contact with the paper web 44 close to the edge 45 thereof, and the contact'member 4| makes contact with the roller 43 just outside the said edge 45 of the paper web. The paper web 44 will provide electric insulation between the contact members 40, 4| and the metallic roller 43. The electrical connections to the starting mechanism of the motor 28 are such that when both contact members 40, 4| are out of electric contact with the metallic roller 43, the motor 28 will rotate in one direction, when the contact member 4| alone is in contact with the roller 43 the motor will not rotate, and when both contact members are in contact with the roller the motor will rotate in the opposite direction; there will not be any position when the contact member 40 alone is in contact with the roller. Such electrical con..

nections are arranged in any known manner and are not illustrated. It will be seen therefore that a slight lateral movement of the paper web 44 on the roller 43 will cause contact member 4| alone, or both contact members, or neither of the contact members, to be in electric contact with the roller 43.

The initial position is that shown in Fig. 1 where contact member 4| alone is in electrical contact with the roller 43, the motor 28 therefore being stationary. If, as the web 44 is travelling around the roller 43, it Wanders laterally to the right (Fig. 1) so that it moves from under the contact member 40 whereby said contact member makescontact with the roller 43, the motor 28 is started up so as to rotate the shaft I9 and so move the sleeve I6 .in the same direction as that in which the web 44 has wandered; the pasting wheel I4 is thereby moved with the web and the paste line is retained in its correct position on the web; simultaneously the bracket 30 carrying the contact members is also moved in the same direction until the position whereby a only contact member 40 makes contact with the web 44 is restored, and the motor 28 will bestopped. If the web moves laterally in the other direction, that is, to the left (Fig. 1), so that it moves under the contact member 4| to remove the latter from contact with the roller 43, both contact members 40 and 4| will thereby be in contact with the web and the motor 28 will be started up to rotate the shaft I9 and so move the sleeve I6 in the same direction, that is, to the left; thereby, the pasting wheel I4 will travel with the web and the bracket 30 will also move until the contact member 4| is moved from contact with the web 44 so that the initial position of the contact members is restored and the motor 28 is stopped.

A wiring diagram, suitable for use with the form of the invention illustrated in Figs. 1 and 2, is illustrated in Fig. 11. Two indirectly heated triode valves IOI and I02 are provided and are fed from rectifier I05; I03 and I04 are grid leaks for valves IOI and I02 respectively. The grid of the valve IOI is directly connected to the contact member 40, while the grid of valve I 02 is directly connected to contact member 4|. The earth connection I03 is on the roller 43.

Loading resistances III, H2 and solenoids I01, I08 are inserted in the circuits of valves IM and I02, respectively, the solenoids I01, I08 being energised when current is flowing through the respective valves. The solenoid I 01 is adapted to actuate a switch I 09, the said switch normally being closed when the solenoid I01 is not energised. The solenoid I08 is adapted to actuate a switch IIO, the said switch normally being open when the solenoid I08 is not energised. Two three-way solenoid operated switching devices are provided in the circuit of the motor 28. One of said switching devices comprises a solenoid 3 which is adapted to simultaneously actuate three switches H4, H5 and "-6, the switch II4 normally being closed and the switches H5 and H8 normally being open when the solenoid I I 3 is not energised; the other switching device comprises a solenoid III which is adapted to actuate three switches H8, H9 and I20, the switch II8 normally being closed and the switches H9 and I20 normally being open when the solenoid H1 is not energised. The switches I09 and H4 are in the circuit of the solenoid III so that said solenoid is energised when said switches are closed; similarly the switches H0 and H8 are in the circuit of the solenoid II3 so that said solenoid is energised when the said switches are closed. The

three phase wires I2I, I22 and I23 and the three terminals I24, I25 and I23 of the motor are concontact with the said roller. In these conditionsthe grid of valve I02 is at the same potential as the roller 43 and this prevents current flowing through valve I02. Sufficient current will flow in the valve IOI to energise the solenoid I01, the switch I09 thereby being opened. Neither of the solenoids H3 and 1 will be energised and the switches H4 and H8 will remain closed and the switches II5, II6, II 9 and I20 will remain open, and no current will flow to the motor, which will remai stationary.

When the paper web wanders to the left, Fig. 1, so that it insulates both contact members 40 and 4| from the roller 43 both valves IOI and I02 allow suificient current to flow to energise both solenoids I01 and I08, the switch I09 thereby being opened and the switch I I0 closed. The circult to solenoid I I 3 is thereby completed, through closed switches H0 and H8, whereupon the switch H4 is opened andthe switches I I5 and II 6 closed. The phase wires I2I, I22 and I23 are thereby connected to terminals I24, I25 and I26, respectiveiy, of the motor, and the motor is caused to rotate in a direction to return the paper web to the right and restore its normal correct runnin position.

When the paper web wanders to the right, Fig. 1, so that both contact members 48 and M are in contact with the roller 48, neither of the valves I8] and I82 passes current. and neitherioi' the solenoids I81 and I88 are energised; the switches I88 and H0 remain in their normal closed and open positions, respectively. The circuit to solenoid III will be completed, through closed switches I88 and H4, and switch II8 will be opened while switches H8 and I28 will be closed. Thereupon the phase wires I2I, I22 and I28 will be connected to motor terminals I24, I28 and- I28, respectively, and the motor will be caused to rotate in the opposite direction to return the paper web to the left and restore its normal correct running position.

In a modified form of the apparatus shown in adapted to slide axially in said bearings.

8| is rigidly secured at one end to the rod 48 Figs. 1 and 2, the sleeve I8 may carry only one contact making device which is normally adapted to make contact with the roller 48, the electric connections to the starting device of the motor 28 being such that the motor normally rotates so as to move the sleeve I8 continuously in one lateral direction, for example, to the right, Fig. l; the transverse movement of the sleeve and the contact making device will move the contact making device towards one edge of the paper web: when thecontact making device moves on to the web the contact between the said member and the roller 48 will be broken and'the motor will be operated to reverse the direction of movement of the sleeve I6 and so restore the normal position with contact-making member in contact with the roller 43. If the web wanders to the right the contact making device will follow it up until the web ceases to wander and the device moves on to the web; if the web wanders to the left it will at once move under the contact making device; in both cases the direction of travel of the contact making device and of the paste box will be reversed until the contact making device again makes contact with the roller 43. Alternatively, the contact making roller may normally be in contact with the web, the reverse movement of the sleeve being affected when the said member moves oil the web on to the roller.

It will be obvious that instead of the pastebox I0 being moved with the sleeve I8 the apparatus maybe modified so that only the pasting wheel I4 in the box may .be moved with the sleeve. It is also obvious that the paste-box may be connected to the sleeve in any suitable manner so as to travel therewith; for example, the paste-box may be mounted on a rod or shaft parallel to the shaft I9 and be connected to the sleeve I8 by suitable link or other devices.

It will also be obvious that the invention may be applied to seam adhesive devices other than paste-boxes, for example, devices applying a paste line by means of a gravity feed or pump; the said devices may be moved laterally of the web in manners similar to those described with reference to a paste-box.

The electric contact making device may be associated with a roller other than that directly associated with the seam adhesive device.

In the modified form shown in Figs. 3 and 4 two photoelectric cells 48, 41 are mounted on and fixed to a rod 48 disposed parallel to the shaft I9. The positions of thecells 48, 41v on the rod 6 may be adjusted by any suitable means so that thelight beam to the scanning head of the cell 48 is normally interrupted by one edge of the paper web 44. and the light beam to the scanning head of the cell 41 is normally interrupted by the other edge of the web 44. The rod 48 is supported in bearings inthe frame 28 and is A link and at the other end to the sleeve I8 so that the rod 48 and sleeve I8 will move simultaneously transversely of the frame 28. When the light beams to both photoelectric cells '46, 41 are interrupted the motor is stationary. When the light beam of the cell 48 is allowed to pass to its scanning head an electric circuit is com-. pleted to cause the motor 28 to rotate in such a direction that the sleeve I8 together with the paste-box I8 and the rod 48 are moved to the right, Fig. 3, and when the beam of cell 41 passes to its scanning head the motor is rotated to cause the sleeve I8, paste-box I0 and rod 48 to move to the left, Fig. 3. It will therefore be seen that when the paper web 44 wanders to the right, Fig. 3, it will move out of the path of the light beam to the scanning head of photo-electric cell 48 and the motor will operate to move the paste-box to the right with the web 44, and the rod 48 will also be moved to the right until the position is restored with both light beams interrupted. Similarly, if the web wanders to the left, the cell 41 will operate the motor to move the paste-box I8 and the rod 48 to the left.

In the form of apparatus shown in Figs. 5 and 6 the sleeve I8 is adapted to be moved intermittently laterally of the machine by a ratchet device, the coacting pawl being continuously operated by a motor. As will be seen in Fig. 6, a motor II drives a vacuum pump 82 through gearing 83, the said drive being continuous. The pump 52 is connected by a pipe 54 to a nozzle 55, Fig. 5, and to a cylinder 58. The nozzle 55 .is supported by a bracket 81 rigidly mounted on the sleeve I8 so as to move therewith, and the nozzle is so disposed that the paper web 44 is in contact with the outer surface thereof and so that a hole 88 in the nozzle is normally Just uncovered by the edge of the web 44. When the hole 88 isuncovered, air is drawn therethrough and through the pipe 54 by the pump 52. Two ratchet wheels 58, 88 are rigidly mounted on the spindle I8, or on another spindle coupled thereto by coupling 4| the teeth of the wheel 88 being directed in the opposite direction to the teeth on wheel 68. A lever 82 is rotatably mounted on the spindle I9, between the ratchet wheels 89 and 88, and carries at its upper end two pawls 88 and 84 directed in opposite directions, the pawl 83 being adapted to coact with ratchet wheel 58, and the pawl 84 being adapted to coact with ratchet wheel 80. The lowerend of the lever 82 is connected by a connecting rod 85 to a crank pin 88 eccentrically disposed on a toothed gear wheel 61 which is in mesh with one of the wheels of gearing 53. The two pawls 83, 84 are rigidly mounted on a short spindle 88 rotatably mounted in the upper end of the lever 82, the pawls 64 being connected by rod 88 to a plunger 18 in the cylinder 58. It will be seen that the motor II in addition to driving the pump -52,'causes the lever 62 to oscillate and, according to which pawl 63, 84 is in engagement with its ratchet wheel 59, 88, to rotate the spindle IS in one direction or the other. When the hole 58 in the nozzle 55 is uncovered by the web 44 air will be drawn therethrough by pump 52, and the plunger III will descend gravitationally in the cylinder 58 and allow the pawl 84 to engage the teeth of the ratchet wheel 60; thereby the spindle I9 is rotated intermittently so as to move the sleeve I6, paste-box I8, and nozzle 55 to the left, Fig. As soon as the hole 58 moves under the web 44, and is covered thereby, air will cease to be drawn through said hole, and the pump 52 will draw the plunger up the cylinder 56. The pawl 64 will be drawn out of engagement with the ratchet wheel 80, and the pawl 68 will be moved into engagement with the ratchet wheel 59 whereby the spindle I9 is rotated in the opposite direction and the paste box I0 and nozzle '55 are moved to the right, Fig. 5. The hole 58 will be again uncovered by the web 44 and the cycle of operations will be repeated. If the web 44 should wander to the Fight the hole 58 will be covered, the rotation of the spindle l9 reversed and the paste-box I 0 will also move to the right. If the web 44 should wander to the left the paste box l0 and nozzle 55 will follow it until the hole 58 is covered again by the web. It will be seen that the paste box is continuously moving, its direction of movement being determined by whether the hole 58- in the nozzle is covered or not. Part of the pipe line 54 may be flexible to allow of movement of the nozzle 55.

In the form shown in Figs. 7 and 8 the vacuum pump 52 is connected as before by pipe 54 to nozzle 55 which is provided with a hole 58 adapted to be covered or uncovered by the web 44. The nozzle 'is secured by bracket 51 to the sleeve I8. When the hole 58 is covered, the pump 52 will draw the plunger I0 down the cylinder 56 against the action of a spring 12. Two electric switches 13 and I4 are mounted on a base I5 and are so connected in the circuit of the motor 28 that when the switch I3 is closed the motor 28 is rotated so as to move the sleeve I6 to the right, and when the switch I4 is closed the sleeve I6 is moved to the left. A lever I6 is pivotally mounted on the base I5, and one end thereof is connected by the tension spring I2 to the base the lever I6 is also connected by rod 65 to the plunger I0. When the lever I6 is drawn down by the plunger I8 against the action of spring I2 it makes contact with the switch I4 and closes said switch; when it is raised by the spring it engages and closes the switch I3. It will be seen that if the nozzle 55, when the hole 58 is uncovered, moves to the right, or the Web 44 moves to the left, so that the hole 58 becomes-covered by the web, the plunger ID will be drawn down by the pump 52, the lever I6 will be drawn down to break the switch I3 and close the switch I4, and the motor 28 will operate to move the sleeve I8 and nozzle 55 to theleft. Similarly, when the nozzle moves to the left, or the web to the right, to uncover the hole 58, air will be drawn through the said hole, the plunger I8 will be released and the spring I2 will draw the lever I6 to break the switch l4 I8 to engage one edge of the paper web 44, and the end face of the other bush 88 to enga e the other edge of the web. Two electric switches I8 and I4 are mounted on brackets 88 84, adjustably mounted-on a carrier 8| which is rigidly mounted on an arm 82 in turn rigidly mounted on the sleeve I8 so that the two switches may move to left or right simultaneously with the sleeve, The switches I8, I4 are spaced slightly further apart than the bushes I8, 80, and so positioned that the bushes may move into contact with and close said switches. When bush 80 is in contact with and closes switch 14 the bush I9 is out of contact with switch I8 and said switch I8 is open, and vice-versa. Normally, when the web 44 is running true, both bushes 18, 80 are out of contact with the switches I8, I4 and both of said switches are open. It the web 44 wanders to the left it will push the bush I8 to the left, together with the roller 11 and bush 88, and the bush I8 will engage the switch I8, closing said switch. When switch 13 is closed a circuit of the motor 28 is'closed whereby said motor rotates in such a direction as tocause the sleeve I8 together with paste box III, arm '82, carrier 8|, and switches I8, I4, to move to the left substantially synchronously with the web and close the switch 13, the motor 28 thereby 44. When the web ceases to wander, the carrier 8| will continue to move to the left until the switch I8 is out of contact with bush I9 whereupon the said switch will open and the motor will stop. Similarly, the switch I4 will be closed when the web wanders to the right, and the motor 28 will rotate to cause the sleeve IE to move to the right.

By the use of the invention a marked reduction in production costs is obtained, it being unnecessary to provide a large overlap on the paper forming the tube to allow for wandering of the paste line.

The device may be used in conjunction with an automatic reel control as used on slitting machines.

The invention may be applied to machines wherein waxed or other papers are caused to adhere to each other by the application of heat, where Cellophane or other papers or papers provided with a dry adhesive are caused to adhere to each other by the application of pressure. In such cases the heat or pressure sealing device is caused to follow the wandering paper in the manner hereinbefore described with reference to the paste box. v

What I claim and desire to secure by Letters Patent is:

1. In a paper bag making machine, a rotatable roller supporting a paper web for traveling movement, an externally threaded shaft mounted for rotation in parallel relation to said roller and disposed laterally of the direction of travel of the paper web, an internally threaded sleeve in threaded engagement with said shaft whereby rotation of said shaft will cause said sleeve to move laterally of the direction of travel of the paper web, a seam adhesive device supported on said sleeve. and movable therewith laterally oi. the paper web; said seam adhesive device having an adhesive-applying rotary disc member normally in contact with said paper web adjacent one edge thereof for applying a narrow layer of adhesive to the paper web, a bi-directional rotary device connected to said shaft for rotating it in either direction, and means responsive to lateral move, ment of the paper web on said roller for determining the direction of rotation of said rotary assays-7 device, whereby the seam adhesive device is moved in the same direction as and substantially said sleeve and movable therewith laterally of the paper web; said seam adhesive device having an adhesive-applying member normally in contact with said paper web adjacent one edge thereof, a bi-directlonal electric motor geared to said shaft for rotating it in either direction, and switching means in the circuit of said motor and having a pair of contacts one normally in contact with said roller and the other resting on said paper web and thereby insulated from said roller, the organization being. such that lateral movement of the paper web on its roller in one direction will permit both contacts to contact with the roller thereby closing the circuit and causing the motor to rotate in one direction and lateral movement of the paper web in the opposite direction will insulate both contacts from said roller and cause the motor to rotate inthe opposite direction.

3. In a paper bag making machine as set forth in claim 2, said contacts being mounted on a bracket secured to said sleeve and disposed at diametrically opposite sides of the roller.

4. Paper bag making machinery according to claim 1, wherein an air suction pump is provided and is adapted to be continuously operated, the said pump is connected by a pipe line to a nozzle mounted on the said sleeve so as to travel therewith, an air inlet orifice in said nozzle is adapted 10 a to be disposed adjacent to one edge of the paper web so as to be covered or uncovered by said web when the web wanders laterally, a cylinder is also connected by a pipe lines to said air pump, a plunger in said cylinder is connected to a lever adapted to operate either, of two electric switches according to the position of the plunger in the cylinder, the said switches are disposed in circuits of a bi-directional electric motor in such manner that the motor is caused to rotate in either direction according to which switch is closed, the plunger is adapted to be moved in one direction in the cylinder by the air pump when the air inlet orifice in the nozzle is covered, and a spring is provided to move the plunger in the opposite direction in the cylinder when the said nozzle is uncovered.

5. Paper bag making machinery according to claim 1, wherein a freely rotatable and axially movable roller is disposed on an axis laterally of the direction of travel of the paper web, two bushes are mounted on said roller and positioned so that they engage the edges of said web and are caused to move laterally by the web when the web wanders, two electric switches are mounted on the said sleeve so as to move therewith and are positioned in relation to said bushes whereby either of said switches is operated by said bushes when the said roller moves axially, the said electric switches being disposed in circuits of a bidirectional electric motor in such manner that.

the motor is caused to rotate in either direction according to which of the said switches is closed.

JOHN NICHOLAS.

REFERENCES CITED UNITED STATES PATENTS Number Name Date 170,383 Wood Feb. 1, 1916 2,049,514

Potdevin Aug. 4, 1936

Images