US2692603A

US2692603A - Watch cleaning machine

Info

Publication number: US2692603A
Application number: US188929A
Authority: US
Inventors: Harold G Foote
Original assignee: George W Borg Corp
Current assignee: George W Borg Corp
Priority date: 1950-10-07
Filing date: 1950-10-07
Publication date: 1954-10-26
Anticipated expiration: 1971-10-26

Description

Oct. 26, 1954 H. G. FOOTE 2,692,603

WATCH CLEANING MACHINE Filed Oct. 7, 1950 2 Sheets-Sheet l IZU f E J7? 5 /a/ 1 y 6 95 422 I33 26 /85 H6 g 5" L36 1 g INVENTOR. HAROLD G, F'OOTE Mia/1W ATTORNEY Oct. 26, 1954 Filed 001;. 7, 1950 .sz /77 60 a4 /2 Wei 0 I; we ms .26 73 INVENTOR.

H. G. FOOTE WATCH CLEANING MACHINE 2 Sheets-Sheet 2 HAROLD c, FOOTE ATTORNEY Patented Oct. 26, 1954 UNITED STATES PATENT OFFICE WATCH CLEANING MACHINE Harold G. Foote, Fontana, Wis., assignor to The George W. Borg Corporation, Chicago, 111., a

corporation of Delaware 28 Claims. 1

The present invention relates in general to cleaning apparatus, and more in particular to apparatus which is adapted for use in cleaning small parts such as the parts of watches and clocks. The general object of the invention may be stated to be the provision of a new and improved watch cleaning machine, adapted primarily for cleaning watch parts but capable of use in cleaning any small mechanical parts of a similar nature.

A feature of the invention is a watch cleaning machine which is substantially completely automatic in operation, the attention of an operator being required only for the purpose of placing the parts in the machine, starting the machine, and removing the parts after they are cleaned and dried.

The foregoing and other features will be described more in detail in the ensuing specification, reference being had to the accompanying drawings, in which- Fig. 1 is a vertical section through a watch cleaning machine embodying the invention, on the line |l, Fig. 2;

Fig. 2 is a horizontal section on the line 22,

Fig. 1;

Fig. 3 is a partial section on the line 33, Fig. 1;

Fig. 4 is a horizontal section on the line 4-4, Fig. 1;

Fig. 5 is a partial section on the line 55, Fig. 1, showing the mechanism for starting and stopping the spinning drive for the parts basket;

Fig. 6 shows part of the link I 16 in the position in which it appears in Fig. 1, the parts in front of the link being cut away on the line 66, Fig. 5;

Figs. '7 to 10, inclusive, are detailed views, partly diagrammatic, which show the raising and lowering mechanism for the parts basket at difierent stages of operation;

Fig. 11 is a view of the lifting cam and associated parts shown in Fig. 8 as seen from above and looking in a direction which is perpendicular to the lifting lever [58.

Fig. 12 is a partial section on line l2i2, Fig. showing details of the lost motion device; and

Fig. 13 is a diagrammatic circuit drawing showing the electrical wiring of the machine.

Referring to Figs. 1 and 4 of the drawings, the machine includes a tank which serves as a container for the jars of cleaning and rinsing fluids and also functions as a frame for supporting various parts of the machine. This tank comprises a bottom or base l0, side walls It and I2,

a rounded front wall l3, and a rear wall M which is spaced inward a short distance from the rear end of the base. There is a downwardly extending flange or rim It, all around the base, as indicated in Fig. 1. This rim has a foot I! in front and two feet such as I8 at the rear which rest on the table or bench where the machine is installed.

A partition 15 extends from the front wall [3 to the rear wall It and forms an enclosure for the jars 20, 2|, and 22, which rest on ribs formed on the base it as shown. These jars may be made of any suitable material, such as stainless steel, for example. Jar contains a washing solution suitable for the purpose, containing soap or a detergent, for example, or any desired cleaning fluid. Jar 2| contains a rinsing fluid such as carbon tetrachloride, for example, while jar 22 contains a second rinsing fluid which may be alcohol, for example.

For the purpose of heating the cleaning and rinsing fluids the enclosure or tank proper in which the jars are located is filled with water up to a couple of inches or so of the top and an electrical heating element 23 is mounted on the base In against the lower surface thereof. This heating element may be of any suitable type and is connected in circuit with a thermostatic switch 24, also mounted on the base It]. The connections are shown in Fig. 13 and will be described at a later point in the specification.

Between the partition l5 and the wall l2 of the tank there is a compartment 28, in which air may be heated by contact with the partition and the adjacent walls. An opening 29 is provided to admit air from beneath the ba e l0. One or more bafiles (not shown) may be provided to divert the flow of air horizontally, if desired.

The front wall 13 and the side walls II and i2 of the tank are provided with an external horizontal rib 30 near the bottom and a flange 3! at the top. This rib and the flange are connected at the rear by external

vertical ribs

32 and 33. The outside casing 34 may be made of sheet metal and is supported on

ribs

30, 32, and 33 and flange 3! in spaced relation to the Walls of the tank, as shown in Figs. 1 and 4.

The rear wall M of the tank has a wide flange 35 at the top which connect the side walls H and I2 and with the flange 3| forms a continuous surface on which the cover plate 36 is supported. The cover plate is secured against displacement by means of the

hinges

31 and 38. The hinge 31 comprises a short piece of rod having a section of reduced diameter which passes through a hole in the cover plate and is secured thereto by a nut 45, and a curved section which extends downward through a hole in the fiange 35. The hinge 38 is the same. These hinges make it possible to raise the cover plate by rotating it about the rear edge 39 as a fulcrum, as can be seen clearly enough from Fig. 1. A nut 41 at the end of the hinge rod 31 and a similar nut on hinge rod 38 limit the extent to which the cover may be rotated to about 90 degrees, which is sufficient to expose the interior of the tank and the jars 2022.

The cover plate 36 is provided with four opening indicated by reference characters 42' to 45, respectively. The first three of these openings are in alignment with the jars 20, 2|, and 22, respectively, and are slightly smaller in diameter. air compartment 28. Each opening is, surrounded by a raised rim such as the rim 46 which surrounds the opening 45, and all four rims are joined by and merge into a circular rim 4?. The rim 4'! is provided with four equally spaced notches which are indicated at 48, 49, B, and 5|, a shown in Fig. 2.

The reference character 52 indicates a disc, preferably of metal, which rests on the rim 41, also the rims such as 45, and effectually closes all the openings in the cover plate 35 except one. The disc 52 has an opening 53, shown in Fig. 2 as being in alignment with the opening 52, whereby this opening and the jar beneath it are exposed and rendered accessible. The disc 52 is rotatable to expose the other openings in the cover plate 36 successively, as will be described later Mounted on the cover plate 36 there is a rotatable frame which is indicated generally by the reference character 55 in Fig. 1. This frame may be an aluminum casting and comprises the top 55, the depending sides 5'! and 58, and the web 58 which connects the sides at the right. The frame is tapered at the left, as can be seen in Fig. 2, and the sides 5'5 and 58 are merged to form a rounded end 65. The top 56 slopes upward to the right, but at the rounded end of the frame it is horizontal and is provided with an integrally formed cylindrical bearing member 8|. This bearing member is fitted with bushings by means of which it is rotatably supported on the post 62, extending upward from cover plate at the center of the circular rim ll. The post 62 is secured to the cover plate in an suitable manner, as by means of a screw 63. From the foregoing it will be understood that the frame 55 is rotatable in a horizontal plane about the post 62 as an axis.

The stud 64 maybe formed integrally with the top 56 of the frame 55 and extends downward through a hole in the disc 52. A central opening in the disc provides room for the bearing member 6! and the helical spring 65 which surrounds it. One end of this spring is hooked around the stud 64, while the other end is secured to the cover plate 36 by means of the screw 61. The spring 65 tends to rotate the frame 55 in a clockwise direction as seen in Fig. 2. The frame is locked in the position in which it is shown by means engaging the notch 28 in rim 4?, as will shortly be described.

A short stud 86 extends downward from the rounded end 68 of the frame and through a slot in the disc 52. The studs 65 and E i serve to keep the disc 52 in position on rim 4'1 and also serve to The fourth opening is above the warm rotate the disc whenever the frame 55 is rotated. That is, the disc rotates with the frame.

Near the ri ht hand end of the frame 55 there are two upwardly extending members 6'! and 68 which constitute inwardly offset extensions of the side members 5'? and 58, respectively. The member 65 is seen in Fig. l and both members are shown in Fig; 3. These frame members support the shafts H and T2. The frame member 5'! is square on top, while frame member 68 is provided with an upwardly extending, projection 18 the purpose of which will be explained presently.

The reference character 73 indicates a motor which may be of any suitable type adapted to run on commercial alternating current. Preferably, however, a so-called universal motor is used, adapted to operate on either alternating or direct current. The motor is enclosed in a housing which comprises the two sides It and 15, the rear end Ti connecting the two sides, and the top 15.. The side M is seen in elevation in Fig. 1, the lower outline being shown by a dotted line where it is obscured by other parts. Side 15, which is cut away in Fig. 1, is identical with side Hi. The two sides 14 and "F5 are outside the

frame members

51 and 58 and extend parallel to each other to a point to the left of motor '13 where they converge as indicated in Fig. 2 and again extend parallel to each other to the end of the housing. The top 16 of the housing has a large opening therein to give access to the motor and associated parts. To the left of this opening the top, curves downwardly, forming a nose having a rounded upper surface, as indicated in Fig. 1.

The opening in the top 16 of the motor housing is closed by a cover is, which is held in place by a screw 19 and two similar screws (not shown) which pass through the cover and are threaded into, tapped holes in the top 16 on opposite sides of the opening.

The motor housing is pivotally mounted on the

frame members

61 and 68 by means of the shaft l2 which has bearings in the sides i and '.'5 of the housing and also in the frame members. This shaft is rotated by motor 73 as will presently be described and also functions as a pivotal support for the motor housing.

The motor 73 is supported in the housing by means of a bracket of rather complicated construotion which will now be described. The bracket comprises a flat ring 84 which is secured to the end of the motor frame by two screws as shown in Fig. 3, two forwardly extending

bearing members

82 and 83 which support the horizontal shaft 84, two

members

85 and 86 which extend to the right from the base of the bearing member 83 and support the vertical shaft 81, and the flange 88 which connects the

members

85 and 86. The flange 88 rests against the side M of the motor housing to which it is secured by means of screws as shown. These parts are all shown clearly in Fig. 3 and some of them also in Fig. 1.

The motor shaft is indicated at and carries the worm 85, which is in mesh with the worm wheel 55 on shaft 84. The motor therefore drives the shaft 84 by means of worm 89 and worm wheel 95; Shaft 64 drives the shaft 31 by means of the worm 9 l' and the worm wheel 92, the former being carried on shaft 84 and the latter on shaft 81. The shaft 87 is rotatably supported by bearings in members 85 and 8B and carries the worm 93 which is in mesh with the worm wheel 94 on shaft 12, whereby the latter shaft is driven from shaft 81. The shaft 84 rotates at a speed of about 230 R. P. M., while shaft 12 rotates at a speed of about 1 rotation in five minutes. These speedsv are not at all critical, but have been found to be satisfactory.

Mounted at the left hand end of the motor housing there is a supporting bracket 99 for the washing basket I08. The bracket 99 is preferably a metal casting and comprises the vertical side members IOI, I02, and I03 and the lower end member I00. A shaft I04 extends through the sides I4 and I5 of the motor housing and through bearings in the side members I02 and I03 of the bracket 99, whereby the latter is pivotally supported on the motor housing.

The cylindrical bearing member I05 extends downward from the end member I of bracket 90 and is fitted with bushings as shown for rotatably supporting the shaft II2. The hub I06 of the short cylindrical flanged member I0! is secured to the lower end of shaft II2 by means of a set screw I I0. The hub I06 has an upwardly extending skirt III to protect the lower bearing of shaft I I2 against the entrance of cleaning or rinsing fluid when the machine is in operation. The washing basket I00 may be of any suitable type. As indicated in Fig. 1 it comprises an upper ring I I3 which is removably secured to the flanged member I 0! by bayonet joints such as I09, and a depending skeleton frame H5 which supports the parts containers such as II4 made of wire screen cloth. There may be three of these containers stacked one above the other as indicated.

The basket I03 is lowered into and raised out of the jars such as 20 by rotation of the motor housing on the shaft I2. The basket is shown in its lowered position in Fig. 1, where it is wholly immersed in the fluid in jar 20. is determined by the engagement of roller I40 with the projection I0 on frame member 68, which limits the rotation of the motor housing in a counterclockwise direction. The roller I40 is mounted on shaft I4I which is an extension of shaft 84, Fig. 3. The shaft I4! is slightly eccentric or off center with respect to shaft 84 so that rotation of the latter shaft produces an oscillatory movement of the motor housing about shaft I2. While the eccentricity of shaft MI is small, it is sufficient to produce a substantial oscillatory motion at the left hand end of the motor housing, where the bracket 99 and basket I03 are supported. The motion of the basket may be about inch, for example.

Since the bracket 90 and the basket I08 are suspended from shaft I04, they tend to remain in a vertical position when the basket is raised or lowered by rotation of the motor housing on shaft I2. However, it is desirable to positively maintain the vertical alignment in order to insure safe passage of the basket through the openings such as 42 and to this end a link I I3 is provided. This link extends lengthwise of the motor housing as indicated in Fig. 1 and at its right hand end it is connected to the shaft H by means of a hub I I0 and set screw as shown in Fig. 3. The left hand end of the link I I6 is provided with a bearing hub II8 which is rotatable on the shaft ill. This shaft extends through the sides I02 and I03 of the bracket :99 and through the link II6 and its bearing hub H8 and is similar to shaft I04 immediately above it. The shafts i2 and 'II and shafts I04 and H1 define a parallelogram. The shafts I2 and H are fixed in vertical alignment. It follows that when the motor housing is rotated about shaft I2 to raise or lower the basket I00 the shafts I04 and II! remain in vertical alignment also. I

This position In order to partly balance the weight of the motor housing and the parts supported thereon a spring 21 is provided and is tensioned between a pin fixed to the link II6, Fig. 1, and a pin projecting upward from the top of frame member 61, Fig. 3. This spring reduces the load on roller I40 during oscillation of the basket I08 and also reduces the load on the mechanism forraising and lowering the basket when this mechanism is in operation, as will subsequently be described.

The mechanism for driving shaft I I2 from motor 13 to spin the basket I08 will now be described. This mechanism includes parts mounted on the plate I20, Figs. 1 and 5, which is attached to the motor by means of the through bolts which hold the two halves of the motor frame together, somewhat longer bolts being substituted for the bolts which come with the motor. The plate I20 has a central opening through which the motor shaft and a part of its bearing extend.

The reference character I3I indicates a short shaft which has a bearing in the block I29 fixed to plate I20. The pulley I2I is secured to shaft I3! by means of a set screw (concealed by the belt) and the shaft is connected with the shaft I I2 by means of a section of flexible shafting I32. The flexible shaft is of the proper length to maintain the pulley IZI in light engagement with the end of block I29. The pulley I22 is mounted on the motor shaft 95. The pulleys I23 and I24 are mounted on the lever I25 which is pivoted on the block I30 by means of a shoulder screw I26. Block I30 is fixed to plate I20. The belt I28 is looped around the pulleys as shown in Fig. 5 and normally is loose, so that the rotation of pulley I22 will not drive pulley I2I.

The belt I20 is tightened at the proper time by an arrangement which includes a helical spring I21, the roller I33, and the cam I34. The roller I33 is mounted at the end of lever I25 on a portion thereof which is bent to the rear at right angles as indicated by the dotted line. The cam I34 is adjustably mounted on the link III; as shown in Figs. 5 and 6, by means of a screw I36. The spring I2I tends to rotate lever I25 in a counterclockwise direction about its pivot I26, but when the apparatus is in the position in which it is shown in Fig. 1 such rotation is prevented by the engagement of a portion of cam I34 by the roller I33. When the motor housing is rotated on its pivot I2 to raise the basket I08, there is a relative movement between cam I34 and the roller I33 which brings the latter into aligmnent with the cut-out I35 in the cam. This occurs when the basket I00 leaves the fluid in the jar and with the motor housing approximately in a horizontal position and enables the spring I2! to rotate lever I25 and tighten belt I28, roller I33 descending into cut-out I35 as far as necessary for this purpose. The belt I20 being tight, the pulley I2I is driven by pulley I22 to spin the basket I08, assuming that the motor I3 is runing. As the motor housing continues its rotation on shaft I2 to raise the basket I08 above the cover plate 30 the roller I33 rides up on another portion of cam I34 to loosen the belt and again disconnect the drive.

It will be convenient now to describe the mechanism for rotating the motor housing on shaft I2 to raise and lower the basket I08. This mechanism is partly shown in Figs. 1 and 3 but can best be explained with reference to Figs. 7 to 11, inclusive.

The disc I45 is rigidly mounted on the shaft I2 by means of the hub I46. The disc has three projecting cams I41, I48, and I49. The stud II has a section I52 of reduced diameter which extends through a hole in the side 15 of the motor housing. The section I52 is threaded to receive the nut I54 by means of which the stud is rigidly secured to the housing. The stud I5I has another section I53 of reduced diameter on which the arm I50 is pivotally mounted as shown. Arm I50 has a downwardly extending part which is bent as shown in Fig. 11 to provide a laterally offset part I55 on which the roller I58 is mounted as shown. At the right hand end of arm I50 there is a short cylindrical member I51, which has a section of reduced diameter extending through a bearing hole in arm I50. The end of this section may be riveted outside a washer which is provided, whereby member I51 is rotatably mounted on arm I50. The member I60 is rotatable on shaft II. The screw I58 extends through a hole in member I51 and is threaded into a tapped hole in member I60. The helical spring I59 surrounds the screw I58 and is compressed between member I51 and member I60. The member I51 can slide on screw I58 by further compressing spring I59 but the spring is quite stiff and in the normal operation of the machine such movement does not take place.

In Fig. 7 the parts of the raising and lowering mechanism are shown in the position which they have in Fig. 1, where basket I08 is immersed in the fluid in jar 20. The dotted line I55 represents the axis of the shaft of motor 13 which along with the motor housing is rotatable on shaft 12. The stud I53 is fixed to the motor housing, this fixed relation being indicated by the dotted line I06. The roller I56 on arm I50 is adjacent the periphery of the disc I45 but not in contact therewith.

Assuming that the motor 13 is running, the disc I45 is rotating slowly in the direction of the arrow thereon and eventually the cam I41 reaches and engages the roller I56. The continued rotation of the disc and cam now exerts a downward pressure on the shaft I I, said pressure being applied through the roller I 56, arm I50 and its pivot at I53, member I51, spring I59, and member I00 on shaft I1I. The spring I59 cushions the engagement between cam I41 and roller I55 but does not yield appreciably thereafter, and since shaft H is fixed against downward movement, the pressure thereon exerted by the cam I41 through arm I50 causes the entire motor housing assembly to rotate in a clockwise direction on shaft 12.

The direction of rotation is indicated by the arrow associated with stud I53 in Fig. 8, this stud being used as a convenient reference point. In Fig. 8, the stud and motor housing are rotating in the direction of the arrow about shaft 12 as an axis and the housing and motor have reached a substantially horizontal position, as indicated by the position of the dotted line I85. The roller I55 has moved away from the disc I45 somewhat, but is still engaged by the cam I41.

As the rotation of stud I53 and the motor housing continues beyond the Fig. 8 position, the subassembly which includes member I51, screw I58, and member I00 begins to rotate in a counterclockwise direction on shaft II, with the result that the roller I56 moves farther away from disc I45. As the parts are shown in Fig. 9, the roller I56 has moved far enough so that cam I41 is able to pass the roller and no longer exerts any downward pressure on it. The motor housing has now reached the limit of its rotation on shaft 8 12 and is in its highest position, as indicated by the position of the dotted line I65. The motor housing remains stationary in this position momentarily while the cam I41 is passing dead center.

As the rotation of disc I45 and cam I 41 continues, the roller I55 rides down the sloping rear face of the cam, permitting the stud I53 and motor housing to rotate rapidly in a counterclockwise direction. This movement is depicted in Fig. 10, where the parts are approaching their lowermost position, as indicated by the position of the dotted line I65. As the downward movement continues, the roller I40 on shaft I4I engages the projection 10, Fig. 1, and the movement is arrested, the parts having resumed the position in which they are shown in Fig. 7, except that cam 41 has passed beyond roller I56. The time interval for the complete cycle is about 15 seconds.

As previously mentioned the horizontally rotatable frame 55 is urged to rotate in a clockwise direction, Fig. 2, by the spring 65, but is restrained against rotation by means engaging the notch 40 in rim 41. This means comprises the downwardly extending pin or stud I10 mounted on the lever I12. The lever I12 is pivoted at I14 on the extension I10 of the bracket I1I which extends across the frame 55 and is secured 'to the lower edges of the

sides

51 and 50 thereof by means of screws, as shown in Figs. 2 and 3. As seen in Fig. 2, the lever I12 is slotted where the pivot I14 passes through it and is urged to move along the pivot by the spring I15 which is tensioned between the adjacent end of the lever and a pin fixed to the bracket I1I. Spring I15 is a rather light spring, however, and the more powerful spring 55 maintains the parts in the position in which they are shown, the pivot I14 engaging the end of the slot in lever I12 and the pin I10 on the lever engaging the wall of the notch 48 in the rim 41.

The lever I12 is operated to release frame 55 by means of a lost motion device on shaft 1 I which will now be described. This device comprises a metal strip bent to the shape of an inverted U and having holes in the sides I11 and I18 through which the shaft I1I extends, a short cylindrical member I8I adjustably fixed on the shaft by means of a set screw, and a pin I19 which extends through member IOI near the outer circumference thereof and parallel to shaft 1I. These parts are shown in Fig. 3 and on an enlarged scale in Fig. 12. The side member I18 has an extension arm I the lower end of which is disposed adjacent the end of lever I12, as shown in Figs. 2 and 3.

When the motor housing is rotated on shaft I2 in the manner described the link I I6 is rotated also, due to the connection between the motor housing and the link at I04, 09, and II!. The link II6 rotates about the axis of shaft H but since the link is fixed to the shaft, the latter is rotated in a clockwise direction as seen in Fig. 12 and rotates member I8I carrying the pin I19. This rotation is ineffective during the greater part of the movement of the motor housing but shortly before the parts have reached their Fig. 9 position the pin I13 on member I8I engages the side members I11 and I10 and thereby causes the extension arm I80 to rotate the lever I12 on its pivot I14. The rotation of lever I12 releases the frame 55 by moving the pin I10 out of notch 48, whereupon the spring 65 starts to rotate the frame in a clockwise direction about 9 the post 92. The parts are adjusted so that the release of the frame takes place after the basket I98 has been raised out of jar 29 and above the cover plate 36 but before the upward movement has been entirely completed.

When the frame 55 is released as described, the spring IE moves the lever I72 longitudinally along the pivot I'M as far as the slot in the lever will permit, which is far enough to enable the end of the lever to clear the arm I89 and permit the arm to go by as the upward movement of the basket I98 continues. The spring I15 also tends to rotate the lever I12 on its pivot I74, with the result that when the frame 55 has rotated 90 degrees the pin I'ZII falls into notch 49 and the rotation of the frame is arrested at that point. The engagement of pin I'IEI with the side of notch 49 moves lever I12 along its pivot I14 against the tension of spring I'I5 until the end of the lever engages the side of arm I8B. Short- 1y after this takes place the parts reach their Fig. 9 position and then begin to descend, the link IIS rotating shaft II in a counterclockwise direction as seen in Fig. 12. As the parts arrive approximately at their Fig. position the pin I79 on member ISI engages the side members Ill and H9 above center and the continued rotation of shaft lI restores arm I80 to the position in which it is shown in Fig. 2. The lever H2 then completes its longitudinal movement along the pivot I74 so that the end of the lever is again operatively related to arm I89 as shown. This final movement of lever I12 permits a slight further rotation of the frame 55, but such further movement is insufficient to appreciably affect the positional relation between the basket I98 and the jar 2! in which it is now located.

It will be noted that the spring I75 is effective to substantially reduce the shock which results when the rotation of frame 55 is arrested by engagement of the pin I19 in notch 49, and thereby prevents any damage to the parts con cerned. The shock may be further reduced by making the arm I89 somewhat. flexible, which will also eliminate most or all of the slight further rotation of the frame referred to in the preceding paragraph.

The lever Il2 projects outside the frame 55 through a slot in the side wall 58, so that it can be operated by hand whenever necessary or desirable.

The electrical wiring will now be described with reference to Figs. 1, 4, and 13.

The plug I89 and socket I89 are mounted on the base I9 behind the Wall I4 of the tank as shown in Fig. 4. Current is supplied to the plug I38 by means of a socket E85 and the two conductor cord I84, the latter terminating in a plug (not shown) which can be inserted in any convenient socket wired for 115 volt comrnerical current. The switch 25, heater 23, and thermostatic switch 24 are connected to the terminals of the plug I88 in series. Switch 25 also supplies current to socket I89. This switch may conveniently be mounted on the rim I6 at the front of the machine.

The two conductor cord I85 terminates in the plug I81 which is normally inserted in socket I89. In Fig. 4 both plug I81 and socket I86 have been removed to expose the socket I89 and plug I88 with which they cooperate, respectively. The cord I85 extends upward through a slot in the flange 35, through the short piece of conduit I99 which is fixed in a hole in cover plate 36, and thence in a loop to the grommet I9I through which it passes to the interior of the motor housing. In Fig. l the cord I is shown as being broken off just inside the housing, to avoid concealing other parts. However, it extends to the right beneath the cover '18, past the flange 88, around inside the end TI of the housing, where it may be secured by suitable clips (not shown), and thence through an opening in the end 59 of frame 55 to terminals on the switch 25. The other terminals of the switch are connected to the motor I3 by conductors extending beneath the shaft 7 I.

The switch 25 is the main switch and is operated by hand to turn the machine on and off. The switch 25 controls the circuit of motor I3 and is actuated automatically by means of the upwardly projecting lugs I92 and I93 on the cover plate 38 responsive to rotation of the frame 55. The lug I92 opens the switch, while lug I93 closes it. In order to prevent any danger of damage to the switch 29 when the frame 55 is rotated in a counterclockwise direction a stop is provided, comprising a rubber block I94 mounted on a bracket I95 which is secured to the cover plate 36 by a screw I96. A similar stop may be provided to limit rotation of the frame 55 in the other direction. However, it is preferable to provide a small curved metal member I9l which is secured to the rim 4! by means of a screw and makes the notch 5! deep enough so that the frame cannot be released from this position by accidental operation of lever I12.

The machine and parts thereof having been described, the operation of the machine in cleaning the parts of a watch movement, for example, will now be explained.

It may be assumed that the

jars

20, 2I, and 22 have been filled about half full with the desired cleaning and rinsing fluids and that the tank I3--I4, has been partly filled with water, as mentioned in the previous description. At this time the frame 55, and the motor housing stand in a position in which they are rotated 270 degrees in a clockwise direction from the position in which the frame is shown in Fig. 2, the frame being held against further rotation by notch 5I. This is the starting position, also the drying position. The switch 26 has been opened by engagement of its actuating member with the projecting lug I92. The motor housing is in its extreme elevated position, indicated in Fig. 9, being supported in this position by cooperation of cam I49 with roller I56. The cam disc I45 is rotated 180 degrees from the position in which it is shown in Fig. 9. The basket IE8 is above the opening 45 in the cover plate 36. The opening 53 in disc 52 is aligned with opening 45 and the

other openings

42, 43, and 44 in the cover plate are closed by said disc. This feature prevents accidental contamination of the fluids in the jars when the machine is idle and also tends to prevent loss of fluid by evaporation.

The operator may now close the switch 25 to start the machine, which energizes the heater 23 to heat the tank and the water contained therein. The water circulates around and under the jars and heats the jars and fluids contained therein to the desired temperature, which is maintained at a substantially constant value by the thermostatic switch 24. A temperature of degrees F. has been found to give very satisfactory results. The thermostatic switch is adjustable and may be set for different temperatures over a considerable range.

When the machine has warmed up sufificiently,

the operator may remove the basket I80 and place the watch parts therein, after which the basket is replaced. The operator then rotates the motor housing and frame 55 in a counterclockwise direction by means of handle 86 on cover I8 until the frame engages the stop Ie4, whereupon the pin I70 drops into notch 43 and locks the frame in this position. Disc 52 rotates with frame 55 and uncovers the opening 42 above jar 20. The rotation of the frame tensions the spring 65, and also closes the switch 26 by engagement of its actuating member with the projecting lug I93. The operator may now leave the machine and attend to other duties.

The closure of switch 26 starts the motor 13, which rotates the

shafts

84 and 12 as previously explained. The rotation of shaft I2 advances the cam disc I45 with the result that cam I49 moves past roller I56 and the basket is quickly lowered through the opening 42 in the cover plate and into the jar 20. The roller I46 is now in engagement with the projection :8 on frame member 68, and since shaft 84 is rotating, the basket I08 is oscillated up and down in the cleaning fluid contained in jar 20.

The machine is now in the position in which it is shown in Fig. 1, which may be referred to as the cleaning position. It remains in this position for an interval which is determined by the spacing of cams I49 and M1 and the rate at which the cam disc I45 is rotated. In the machine described this interval is about 2 minutes, or a little more.

The cleaning operation is terminated when cam I41 engages the roller I55 to rotate the motor housing on shaft I2 as previously described in connection with Fig. 8. When the rotation starts the roller I40 moves away from projection 10 and the oscillatory motion of the basket I08 ceases. The rotation of the motor housing on shaft I2 raises the basket I08 and when the basket arrives at a position in which it is above the cleaning fluid but is still in the jar the roller I33 on lever I reaches the cutout I in cam I34, thereby permitting lever I25 to tighten the belt I28 and start spinning the basket I08. During this operation the basket is rotated at high speed to throw off the cleaning fluid from the basket and the parts contained therein by centrifugal force, and since the operation starts while the basket is still well within the jar no substantial amount of fluid is lost. The spinning operation stops when the basket begins to emerge through the opening 42, or shortly thereafter, due to the movement of roller I33 out of the cut out I35, but by this time substantially all the cleaning fluid will have been thrown off to drain back into the jar.

Shortly before the motor housing reaches its Fig. 9 position, and when the basket I08 has been raised entirely above the cover plate 36, the arm ISII operates the lever I12 to release the frame 55, whereupon the spring 65 rotates the frame 90 degrees and it again becomes locked by the engagement of pin I'I0 with the notch 49. The disc 52 rotates with the frame, covering the opening 42 in the cover plate 36 and exposing the opening 43 above the jar 2|. The cam I4? on cam disc I45 then passes the roller I56 and the basket I08 is quickly lowered into the jar 2I. This jar contains a rinsing fluid and the position now occupied by the basket 38 may be referred to as the first rinsing position. It will be noted that when the basket I08 is lowered into the jar the spinning drive will again be connected momentarily but this does no harm.

The roller I40 is now in engagement with the projection I0 and the basket I08 is oscillated up and down in the rinsing fluid in jar 2!. This rinsing operation continues for about one minute, or until the cam I48 on disc I45 engages the roller I56, whereupon the basket I88 is raised out of jar 2| in the same way that it was previously raised out of jar 20. During the upward movement of the basket the spinning drive is again connected to throw off the surplus rinsing fluid.

When the basket I08 has been raised above the cover plate 36, the arm I again actuates the lever I'I'2 to release frame 55, which rotates another 90 degrees and becomes locked by engagement of the pin I10 with the notch 50. The disc 52 rotates with the frame, covering the opening 43 and uncovering the opening 44 above which the basket I08 is now positioned. The cam I48 now passes the roller I58 and the basket is lowered into the jar 22. This is the second rinsing position.

The roller I4I] cooperating with projection It? now oscillates the basket I08 up and down in the rinsing fluid in jar 22, the operation continuing for about one minute. The operation is terminated when the cam I49 engages the roller I56 to raise the basket I63 from the jar 22. During the upward movement of the basket the spinning drive is connected as before to throw oif the rinsing fluid from the basket and parts contained therein.

When the basket has been raised above the cover plate, the arm I80 actuates lever I72 as before to release the frame 55, which thereupon rotates 90 degrees further and becomes locked by the engagement of pin I19 in notch 5|. Disc 52 rotates with the frame to cover opening 44 and uncover opening 45. The rotation of the frame causes the actuating member of the switch 26 to engage the projecting lug I92 on the cover plate, which opens the switch and stops the motor 73. At this time the motor housing and basket are in their uppermost or Fig. 9 position, and the cam I49 is on dead center with respect to roller I56. The cam I49 is preferably a few degrees wider than the other cams and has a fiat end which allows for some coasting of the motor before it completely stops.

The machine is now in drying position. The watch parts in the basket have been substantially freed of rinsing fluid by the spinning of the basket as it was raised in the second rinsing position, and the parts having been thoroughly warmed by their progress through the machine, the remaining fluid is quickly evaporated. The drying of the parts is facilitated by a current of warm air which now pours up through the opening 45 in the cover plate from the chamber 28. This opening has been closed throughout the preceding operation of the machine, so that the air in chamber 28 has become heated to the temperature of the tank.

After allowing sufficient time for the parts to become dry, the operator will take the basket ofi and remove the parts. The drying position is also the starting position and if more parts are to be cleaned they are put in the basket, the basket is replaced, and the machine is started again by rotating the motor housing and frame 55 to their Fig. 2 position, whereupon the described 0D- erations of cleaning, rinsing and drying are repeated. Otherwise the machine is shut off by opening the switch 25.

While a certain concrete embodiment of the invention has been described, this has been done to facilitate the understanding thereof and it will be understood that modifications may be made without departing from the principles of the invention. I do not, therefore, wish to be limited to the precise form of the invention shown and described herein, but desire to include and have protected by Letters Patent all forms and modifications of the invention which come within the scope of the appended claims.

I claim:

1. In a machine for cleaning watch parts and the like, a main container, a plurality of jars in said container disposed on a circle, a cover plate for said container and jars, said plate having openings in alignment with said jars, a closure member in the form of a thin plate resting on said cover plate and closing all said openings except one, said member having an opening therein aligned with one of said openings in the cover plate, a frame rotatably supported at the center of said circle, cleaning mechanism mounted onsaid frame, means for intermittently rotating said frame to position said cleaning mechanism above said jars successively, and an operative connection between said frame and closure member to rotate the latter each time the frame is rotated, whereby the opening in the closure member is successively aligned with openings in said cover plate and said jars are rendered successively accessible to said cleaning mechanism.

2. In a machine for cleaning watch parts and the like, a plurality of individual containers for cleaning and rinsing fluids, a tank in which said containers are disposed and adapted to contain water or other fluid to transmit heat to said containers, an electrical heating element mounted on said tank to heat the same and the water contained therein, a themostatic switch in circuit with said heating element to maintain the tank and water temperature at a desired constant value, means normally covering said containers to prevent a loss of heated fluid by evaporation, washing mechanism including a basket for parts, means for operating said mechanism to cause said basket to enter said containers successively, said covering means including a device for uncovering said containers one at a time, and means for operating said device in timed relation to the operation of said washing mechanism to uncover each container prior to the entrance of said basket therein.

3. In a machine for cleaning watch parts and the like, a tank, a partition dividing said tank into two compartments, one compartment adapted to contain water and the other constituting a chamber for heating air, a plurality of jars in said water compartment arranged in the arc of a circle, means for heating said tank, a cover for said tank having openings therein aligned with said jars, said cover also having an opening above said air chamber, a closure member supported on said cover and spanning said openings, said member having an opening therein located at the same radial distance from the center of said circle as the openings in said cover, and means for rotating said member about the center of said circle to align the opening therein with the openings in said cover successively.

4. In a machine for cleaning watch parts and the like, a plurality of fluid containers disposed on the arc of a circle, a frame above said containers, means supporting said frame for rotation about a vertical axis at the center of said circle, a second frame, means supporting said second 14 frame on said first frame for rotation about a horizontal axis, a motor mounted on said second frame, a parts basket supported on said second frame and depending therefrom in radial alignment with said containers, mechanism driven by said motor for rotating said second frame on its axis to lower said basket into a first one of said containers and to subsequently raise the basket therefrom, control mechanism for repeating the lowering and raising operations, mechanism driven by said motor when said basket is in lowered position to oscillate said second frame on its axis, and mechanism controlled by said motor responsive to each raising operation to rotate the said first frame to position said basket above the next container, whereby said basket is lowered into and raised from said containers successively.

5, In a machine for cleaning watch parts and the like, a plurality of fluid containers disposed on the arc of a circle, a frame, a support at the center of said circle on which said frame is rotatable in a horizontal plane, a second frame pivotally mounted on said first frame, a parts basket mounted on said second frame in radial alignment with said containers, a motor mounted on said second frame, mechanism driven by said motor for rotating said second frame on its pivot to lower said basket into one of said containers and to raise the basket therefrom, means tending to rotate said first frame, latching means for holding said first frame against rotation, and means actuated by said mechanism when said basket is raised for releasing said latching means to permit rotation of said first frame to thereby advance said basket to the next container.

6. In a machine for cleaning watch parts and the like, a plurality of fluid containers disposed on the arc of a circle, a support at the center of said circle, a frame mounted on said support for rotation in a horizontal plane, a parts basket mounted on said frame in radial alignment with said containers, means for rotating said frame to position said basket above the first of said containers, a spring tensioned by such rotation, latching mechanism for holding said frame in said position, there being a fixed stop cooperating with said mechanism, a motor mounted on said frame, means driven by said motor to periodically release said latching mechanism, and a plurality of additional stops arranged concentric with said circle and at angular distances equal to the distances between containers, whereby upon successive releases of said mechanism the resulting rotation of said frame and basket is arrested by cooperation of said mechanism and successive stops to position said basket above the remaining containers successively.

7. In a machine for cleaning watch parts and the like, a plurality of fluid containers disposed on the arc of a circle, a frame above said containers, means supporting said frame for rotation about a vertical aXis at the center of said circle, a second frame, means supporting said second frame on said first frame for rotation about a horizontal axis, a parts basket supported on said second frame at the same radial distance from the center of said circle as said containers, means for rotating said first frame to position said basket above said containers one after the other, including means for holding said first frame in each position, and means effective in each position for rotating said second frame on its axis to lower said basket into the associated container and raise it therefrom.

8. A machine as claimed in claim 7., including a motor mounted on said second frame and supplying power to rotate the second frame on its axis, and mechanism driven by said motor to control rotation of said first frame.

9. A machine as claimed in claim 8, wherein said first frame is rotated by hand in one direction to position the parts basket above the first container and is rotated in the opposite direction to positions above and beyond the other containers under control of said motor driven mechanism, said machine including a switch for controlling the circuit of said motor, and means responsive to rotation of said first frame in said two directions, respectively, to close and open said switch.

10. In a machine for cleaning watch parts and the like, a frame, a motor mounted on said frame, means pivotally supporting said frame for rotation by gravity about a horizontal axis, a parts basket supported on said frame and depending therefrom, a fluid container supported beneath said parts basket, mechanism driven by said motor to control said rotation of said frame to lower said basket into said container, a shaft rotatably mounted on said frame and driven by said motor, means effective to arrest the lowering movement of said basket when the same becomes immersed in the fluid in said container, and mechanism responsive to rotation of said shaft to oscillate said frame on its axis to thereby produce an oscillatory movement of said basket in said fluid.

11. In a machine for cleaning watch parts and the like, a frame, a motor mounted on said frame, means pivotally supporting said frame at one end thereof for rotation about a horizontal axis, a parts basket supported on said frame at the other end and depending therefrom, a fluid container supported beneath said parts basket, mechanism driven by said motor for rotating said frame on its axis to lower said basket into said container, a shaft rotatably mounted on said frame, a roller eccentrically mounted on said shaft, a fixed stop engaged by said roller to arrest the downward movement of said frame and basket when the same is lowered into said container, and a driving connection through which said motor rotates said shaft to oscillate said frame on its axis and move said basket up and down in the fluid in said container.

12. In a machine for cleaning watch parts and the like, a frame, a motor mounted on said frame,

means pivotally supporting said frame at one end thereof for rotation about a horizontal axis, a parts basket supported on said frame at the other end for rotation about a vertical axis, a fluid container supported beneath said parts basket, mechanism driven by said motor for rotating said frame on its axis to lower said basket into said container, said mechanism being effective after a predetermined time to rotate said frame in the opposite direction to raise said basket from said container, a driving connection between said motor and said parts basket, said connection including a clutch, and mechanism effective in an intermediate position of said basket to operate said clutch to thereby cause said motor to spin said basket.

13. In a machine for cleaning watch parts and the like, a frame, a motor mounted on said frame, means pivotally supporting said frame at one end thereof for rotation about a horizontal axis, a bracket pivotally supported on said frame at the other end thereof, a parts basket rotatably supported on said bracket and depending therefrom, a fluid container supported beneath said parts basket, mechanism driven by said motor for rotating said frame on its axis in two directions to lower said basket into said container and raise it therefrom, means for maintaining said basket in a vertical position during the lowering and raising thereof, said means comprising a link pivotally connected at one end to said bracket and having a fixed pivot at the other end adjacent the pivot for said frame, the pivots at opposite ends of said frame and the pivots at opposite ends of said link defining a parallelogram, means including a clutch for transmitting power from said motor to said basket to rotate the same, and mechanism actuated in response to relative motion between said frame and link during the raising of said basket from said container to engage said clutch.

14. In a machine for cleaning watch parts and the like, a frame, a second frame rotatably mounted on said first frame, a shaft rotatably mounted on one of said frames, said shaft and said second frame having the same axis of rotation, a parts basket supported on said second frame, a motor mounted on said second frame, a coupling through which said motor drives said shaft, an element connected to the first frame, and mechanism responsive to rotation of said shaft to cause said second frame to exert a downward pressure on said element to thereby rotate itself on said axis to raise said parts basket.

15. In a machine for cleaning watch parts and the like, a frame, a second frame pivotally mounted on said first frame by means of a horizontal shaft having bearings in both frames, a motor mounted on said second frame, a parts basket supported on said second frame and depending therefrom, a fluid container supported beneath said basket, a connection through which said motor drives said shaft, and mechanism actuated by rotation of said shaft to rotate said second. frame thereon in two directions to thereby lower said basket into said container and raise the basket therefrom.

16. In a machine for cleaning watch parts and the like, a frame, a second frame pivotally mounted on said first frame by means of a horizontal shaft having hearings in both frames, :1 motor mounted on said second frame, a parts basket supported on said second frame and depending therefrom, a fluid container supported beneath said basket, a connection through which said motor drives said shaft, a cam mounted on said shaft, means including said cam normally supporting said second frame and basket in an elevated position, said means being effective upon starting of said motor to rotate said second frame and thereby lower said basket into said container, and means including an additional cam on said shaft operative to rotate said second frame in the opposite direction to thereby raise said basket from said container.

17. In a machine for cleaning watch parts and the like, a frame, a shaft rotatably mounted in said frame, a second frame pivotally mounted for rotation about the axis of said shaft, 9. motor mounted on said second frame, a shaft coupled to said motor and driven thereby, a parts basket supported on said second frame and adapted to be lowered and raised by rotation of the motor driven shaft, lowering and raising mechanism for said basket operatively connected to said second frame, cam means on said motor driven shaft 157 for operating "said mechanism; and 9:3 fluid container mounted onssai'd first-frame into :and @1113 of which sai'd "basket isslowered and raised y operation of said mechanism: 1.; $7.,

18. In a machine for cleaning watch parts and the like,- a'-= frame, a shaft rotatably mounted in said frame,-

secondpframe pivotally mounted on said first frame for rotationa out the axisofisaid shaftjja' motor mounted on said second f a;couplingthroughwhichsaid otor dri essaid shaft, a parts 'basketsupport dpn sa frame anda'daptedtobe lo rotation thereof acam' said s thereby, a jointed link com pivotallyfconnected' to the v V frames, respectivelyya rollerijonthe seco member the path 'of'said camwhen saf V basket is in lowered positionand" from by relative movement whenithebasket israisedfa'ffr I t facej I I cam cooperating with said roller to raise'said basket, and a sloping rear face on said cam cooperating with said roller to lower said basket.

19. In a machine for cleaning watch parts and the like, a frame, a shaft rotatably mounted in said frame, a second frame pivotally mounted on said first frame for rotation about the axis of said shaft, a motor mounted on said second frame, a parts basket supported on said second frame to be raised and lowered by rotation thereof, a coupling through which said motor rotates said shaft in the direction in which second frame is rotated to lower said basket, a cam on said shaft having front and rear working faces, mechanism operatively connected to said frames and operated by the front face of said cam to create a mutually repulsive force between said frames effective to rotate the second frame in the direction to raise said basket, and means included in said mechanism and responsive to said last mentioned rotation to shift the said mechanism relative to said cam, thereby rendering the rear face of said cam effective to cooperate with said mechanism tocontrol rotation of said second frame in the direction to lower said basket.

20. In a machine for cleaning watch parts and the like, a frame supported for rotation about a vertical axis, a second frame pivotally supported on said first frame for rotation about a horizontal a plurality of fluid containers disposed in the arc of a circle having its center on said vertical axis, a parts basket supported on said second frame above said containers and at the same radial distance from said, vertical axis, a motor mounted on said second frame, a shaft rotatably supported on said first frame and driven by said motor, a timing member mounted on said shaft and carrying a plurality of cams, mechanism controlled by said cams to rotate said first frame at intervals to position said basket above said containers successively, and mechanism operated by said cams to lower said basket into each container as the basket arrives thereat' and to raise the basket from each container after a predetremined time.

21. In a machine for cleaning watch parts and the like, a tank adapted to contain water or other liquid, an electrical heating element for heating said tank and liquid, a thermostatic switch in circuit with said heating element to maintain the tank and liquid temperature at a desired constant value, a plurality of upright jars disposed in said tank to be heated by immersion in the liquid in said tank, said jars being arranged in a an; andir g two me bers circle; finCOVGI'EifOI'i said tank cooperating with zthe wal-ls thereof and: the zwallswofxsaid jars to form a::substantlallylclosed :space aboveit thealiquidsin saidkitank; saidiacever having? openings I Ltherein alignediwvitlr'saidnjars; ia closure member resting on isaid coveriandvadaptedato: close saidropenings, said member vhaving 'an: miening thercinulocate'd atzithesam "radial distance fromrtlie centerrof saidwcircler s ithfi openingsnin gsaidq cover, Band means: for e-intermittently :rotating said member about said; centeritoiposition;thecopeniirgftherirr above her-openings inisaidicover asuccessively. .2216111 machine forecleaning..: watch parts and their ike --a frame,-.ia'partsi basketisupported onsaidframe affluid containeridisposed beneath said" basket", gm'echanismneiop'erative 2:170 eimpa'rt movements to. saicl-'vfr ame iopposite: directions torlower salidabasket intoi'sa'id container a'ndraise it'ztherefrom mechanism i op'erative to'l impartk a vibrator movement to ."saidi frame while "the basket inside ssaidicontainer; ta motori'lmounted'aron -saidsframel and'qiantaking in z'rsaid'i movements, and mechanical connections through which said motor drives both said mechanisms. 23. In a machine for cleaning Watch parts and the like, a fluid container, a frame, a parts basket, means including a shaft supporting said basket on said frame above said container, means supporting said frame for rotation about a horizontal axis, mechanism on said frame operative to rotate the frame on said axis in two directions to thereby lower said basket into said container and raise it therefrom after a predetermined time interval, a motor mounted on said frame and having a driving connection to said mechanism, and a driving connection between said motor and shaft completed by the rotation of said frame in the direction which raises said basket.

24. In a machine for cleaning watch parts and the like, a fluid container, a frame, a parts basket, means including a shaft supporting said basket on said frame above said container, a support for said frame, mechanism comprising parts on said frame and support operative to move said frame relative to said support to thereby lower said basket into said container and raise it therefrom, a motor mounted on said frame and movable therewith, a driving connection between said motor and said mechanism, a driving connection between said motor and said shaft, a clutch included in said last connection, and means actuated responsive to the said movement of said frame to connect and disconnect said clutch.

25. In a machine for cleaning watch parts and the like, a horizontally disposed base member, a plurality of fluid containers arranged on said member in the arc of a circle, a support mounted for rotation about a vertical axis passing through the center of said circle, a spring for rotating said support, means for latching said support in a plurality of positions corresponding to said containers, respectively, a parts basket mounted on said support, mechanism operative to impart downward and upward movements to said parts basket adapted to lower the same into and raise the same out of one of said containers, and means responsive to upward movement of said basket to unlatch said sup port to effect movement thereof to its next position by said spring, whereby the continued operation of said mechanism causes said basket to be lowered into and raised from said containers successively.

26. A machine having means for immersion cleansing Of parts in a succession of baths, said means including a mechanism having a motor and mounted centrally of the baths, said mechanism being provided with a support upon which the mechanism is mounted for oscillation on a horizontal axis and rotation on a vertical axis, an arm extending laterally of the mechanism and having a parts basket mounted rotatably thereto, and connections between the motor and the mechanism for sequential actuation of the oscillatory and rotatable motion of the mechanism and arm to sweep the arm and. basket in a succession of immersions of the basket, the sequence being controlled by control devices positioned to be actuated according to the oscillatory position of the mechanism.

27. The machine of claim 26 wherein the connections for sequential motion include means for a succession of modified oscillatory movements when the arm is in basket immersing position.

28. The machine of claim 26 wherein the connections for sequential motion include means powered by the motor for rotating the basket when the arm is in position to hold the basket immediately above a bath.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 169,029 Naven Oct. 19, 1875 1,848,034 Titus Mar. 1, 1932 2,167,185 Preston July 25, 1939 2,184,020 Repasy Dec. 19, 1939 2,236,224 Raschkind Mar. 25, 1941 2,461,113 Friedman Feb. 8, 1949 2,464,730 Sutherland Mar. 15, 1949 2,469,034 Garris May 3, 1949 2,470,409 Nassivera May 17, 1949 2,485,673 State Oct. 25, 1949 2,510,912 Schurenberg June 6, 1950 2,559,921 Aiello July 10, 1951