4571 4575.output

* GB784978 (A)

Description: GB784978 (A) ? 1957-10-23

Improvements in and relating to rotary electric switches

Description of GB784978 (A)

PATENT SPECIFICATIGAL- 784,978 Date of Application and filing Complete Specification: March 29, 1956. No 9968/56. /1 j Application made in United States of America on March 30, 1955. Complete Specification Published: Oct 23, 1957. Index at acceptance:-Classes 38 ( 1), E 3 (A 4 D:A 1 OB 3:B 2 C:C 2 C:C 2 E:C 6 C:D 3:E 3 B); and 38 ( 5), Bl(F 3:F 6), B 2 (A 5 B:A 18:B 10:Cll), B 4 C. Inteenational Classification:-H 01 n, H 02 f. COMPLETE SPECIFICATION Improvements in and relating to Rotary Electric Switches We, GENERAL ELECTRIC COMPANY, a Corporation of the State of New York, United States of America, having its office at Schenectady 5, State of New York, United States of America, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to rotary electric switches. Pull-operated switches commonly employ a pull chain to actuate a rachet mechanism for making and breaking the circuit to the switch. According to the present invention a rotary switch comprises a hollow housing having a stud member projecting inwardly from one inner wall of the housing and four inclined surfaces formed on said wall in a ring surrounding the stud and centred thereon, the parts of said surfaces innermost with respect to the housing being connected by steps with the outermost parts of the next surfaces of the ring, fixed contacts disposed on alternate ones of said surfaces in the ring and the other alternate surfaces of the ring being of relatively narrow width and located between adjacent surfaces projecting inwardly of the

housing, and a rotary contact member mounted for rotation on the stud and having contact blades extending parallel or substantially parallel to the axis of the stud, said blades being adapted to complete the circuit through the fixed contacts by engagement of the edges of the blades with said fixed contacts and to slide over the fixed contact surfaces on rotation of said member so as to ride over said steps and toward said second alternate inclined surfaces so as to open the switch, there being only a narrow clearance between said adjacent surfaces whereby to provide for extinguishing an arc formed between said blades and said fixed contacts. The narrow grooves formed between the the fixed contacts prevent an arc from 50 spreading and eventually burning the contacting parts enabling the switch to have a higher electrical rating for a given cost and increasing the useful life of the switch. Conveniently a ratchet mechanism is 55 arranged on the stud member for driving the rotary contact member, biasing means being provided in the housing and being adapted to return the ratchet to the normal position on release of the latter 60 The housing may conveniently comprise a cover member and a base member, the inclined surfaces and the inwardly projecting stud member being formed in the base member with the fixed contacts 65 and other operative parts of the switch assembled thereon and the top cover fastened to the base member By this means all of the separate switch parts maybe assembled in one-half of the hollow 70 switch housing which may then be closed by simply placing the remaining half of the housing in co-operative engagement therewith, and finally in connecting the two housing parts together This is an 75 important production consideration since the housing parts need not be turned over in order to complete the assembly. One embodiment of the invention will now be described by way of example with 80 reference to the accompanying drawing in which:Fig 1 is an elevation of a combined switch and lamp holder having a pullchain operated switch mechanism, Fig 285 is a view of the combined switch and lamp holder of Fig 1 from behind. Fig 3 is a view of the combined switch and lamp holder of Fig 1 with the screw shell and one-half of the insulating hous 90 2 7 j ing removed, Fig 4 is a left end elevational view of the combined switch and lamp holder of Fig 1. Fig 5 is a top plan view of the comlined switch and lamp holder of Fig 2. Fig 6 is a bottom plan view of the combined switch and lamp holder of Fig 2. Fig 7 is an exploded perspective view of the combined switch and lamp holder of Figs 1-6. Referring to the drawing there is shown in Fig 1 a combined switch and

lamp holder 10 comprising a metal screw shell 1511 and a hollow split housing 12 of suitable insulating material for enclosing a ratchet-type switch mechanism As shown clearly in Fig 7 of the drawing, the split hollow housing 12 is formed of two recessed moulded pieces 13 and 14 of suitable phenolic insulating material The part 13 will be referred to as a base member since all of the switch parts are assembled therein, while the part 14 serves as a cover member to complete the enclosure of the switch mechanism There is an integral stud member 15 moulded in the base 13 which serves as the focal point of the-fixed and movable contacts of the ratchet mechanism Disposed around the stud 15 and centred thereon are a series of inclined arcuate surfaces -16,16 ' conneeted by steps to form a ring of ratchet steps, which it will be seen serve to provide a snap action for the switch mechanism Of these arcuate surfaces the two opposed surfaces 16 are adapted to receive the fixed contacts 17 and i S and the two opposed surfaces 16 ' space the fixed contacts from one another The ratchet surfaces 16 ' are narrower in width than the surfaces 16, being situated between adjacent surfaces 16 a and 16 b (Fig 7), which extend inwardly of the base and are centred on the stud 15, so that two narrow grooves are formed in the base by the surfaces 16 a and 16 b and the surfaces 16 ' The narrow grooves serve as means for extinguishing an arc as is more fully hereinafter explained. The terminal end 19 of the fixed contact 17 is provided with a tapped opening 20 for receiving a terminal screw 21 and is of such a size and shape that it may be seated in the aperture 22 formed in the base 13 The hook portion 23 of terminal end 19 is arranged to be seated on the ledge 24 of the base 13 near the aperture 22 to assist in supporting the fixed contact within the switching housing. Looking at Fig 7 there is an apertured boss 55 on the cover 14 which is adapted to receive the end of the terminal screw 21 as well as to mate with the terminal end 19 of the fixed contact 17 to insure that it is held firmly in place within the base 13 Thus, it will be seen that it is possible to connect a lead wire (not shown) to the switch mechanism by means of the terminal screw 21 which has its head 70 arranged outwardly of the switch housing. Considering Figs 3 and 7 of the drawing, it will le seen that the fixed contact 18 has at one end a centre contact strip 28 serving as the centre contact for the 75 screw shell socket 11 In Fig 3 of the drawing, fixed contact 18 is shown seated on the ratchet step 16 and opposite the remaining fixed contact 17 A slot 29 i; formed in one edge of the base 13 and a 80 similar slot 29 ' is formed in one edge of the cover 14 so that the strip 30 which connects the fixed contact 18 with the centre contact 28 is fitted within the said grooves 29 and 29 ' to be centrally located 85 in the screw shell 11, as is best seen

in Fig 6. A rotary contact member 35 which serves as the movable contact between the fixed contacts 17 and 18 is provided with 90 a central opening 36 so that it may be fitted over the stud member 15 of the base 13 to rotate with respect thereto. Edgewise blades 37 are formed on opposite sides of the contact member 3 95 to have sliding engagement with the fixed contacts 17 and 18 The lower edge 38 of each blade 37 is inclined in the same manner as the fixed contacts 17 and 18 so that there is a flat edgewise engagement 100 between the movable and fixed contacts. Spaced between the blades 37 are a pair of ratchet teeth 39 which are adapted to co-operate with the insulating ratchet member 40 that is fitted over the stud 15 105 on top of the contactor 35. The ratchet member 40 is of fibre material with a central pivotal opening 41 and a series of four ratchet openings 42 equally spaced around the aperture 41 110 An integral arm 43 extends from one side of the ratchet member 40 and it has an opening 44 containing the link member for making engagement with a pullchain 46 of the usual construction An 115 adjustable torsion spring 50 is also fitted over the stud 15 after the ratchet member is in place The lower end 51 of the spring is shaped to fit into the pinhole 47 of the ratchet member 40 to fix that end 120 of the spring with respect thereto The opposite end 52 of the spring 50 is rounded to fit into one arm of the cross-shaped slot 53 formed in the cover member 14 as is best seen in Fig 1 125 The purpose of the cross-shaped slot 53 in the cover member 14 is to permit the adjustment of the sprin tension of the torsion spring 50 Thus, it is possible to use a special tool (not shown) having a 130 784,978 784,978 bifurcated end to depress the spring 50 until the rounded end 52 is free of the slot 53 and then by turning the spring the necessary amount to obtain the desired spring tension after the switch is assembled in the switch housing When the adjustment is correct, the spring may be released by withdrawing the tool so that the rounded end 52 of the spring is 1 o again seated in one of the arms of the cross-shaped slot 53 BY using such a slot it is possible to obtain the fineness of a quarter turn adjustment. The method of assembling this switch mechanism is quite simple in that the base member 13 may be placed on the operator's work bench and the fixed contacts 17 and 18 are dropped onto their respective ratchet steps 16 in the base 13. Then in quick succession the rotary contact member 35 is fitted over the end of the stud 15, and in turn the ratchet memb)er 40, torsion spring 50, and finally the cover member 14 are assembled to form a completely enclosed switch mechanism. After this it is merely necessary to adjust the spring tension of the

torsion spring so that the switch will be ready for use The switch is operated by moving the rotary contact member 35 into and out of engagement with the fixed contacts 17 and 18. This movement is effected by exerting a pulling force on the pull chain 46 which tends to oscillate the member 40 about the 35stud 15 When the switch is opened the edgewise blades 37 of the rotary contact member 35 move out of engagement with the fixed contacts 17 and 18 over the edges of the steps conhecting surfaces 16 and 16 ' and into the narrow grooves formed by the surfaces 16 a and 16 b with a snap action. BY this arrangement of edgewise blades moving over the edges of the steps into the narrow grooves any arc formed on opening the switch is confined by the narrow grooves so as to be prevented from spreading and so burning the switeh parts, and is extinguished The ratchet teeth 39 of the contactor 35 are seated within tbe ratchet openings 42 of the ratchet member 40 so that any counterclockwise movement of the member 40 likewise moves the contactor 35. When the line of force of the pull chain 46 extends through the pivotal axis of the stud 15, any additional pull on the chain wvill be ineffective in rotating the ratchet member 40 When the chain 46 is released, the torsion spring 50 will take over, since it was tensioned by the counterclockwise movement of the ratchet member 40, and it will tend to return the member 40 to its normal position During this return movement of the ratchet member 40, the contact member 35 remains fixed due to the shape of the ratchet steps 16 and 16 ' in the base 13 Consequently the ratchet openings 42 of the ratchet member 40 will move out of driving engagement with the ratchet teeth 39 of 70 the contact member 35 The raised ratchet teeth 39 also serve as a detent mechanism in co-operation with the ratchet openings 42 of the member 40 so that normally the teeth 39 are disposed within opposite 75 ratchet openings 42 Thus, when a pulling force is applied to the pull chain 46, the contact member 35 will be driven by the movement of the ratchet member 40 to make or break the electrical circuit 80 through the fixed contacts 17 and 18. The screw shell 11 has a partial base 56, as seen in Fig 7, which is nearly all cutaway by the enlarged central opening 57. A pair of lanced tabs 58 are struck out 85 of the base 56 to lie opposite and parallel to each other The tabs 58 of the screw shell 11 are each provided with aligned slots 59 so that when the switch parts are assembled in the base member 13 and the 90 cover member 14 is disposed thereover, the tabs 58 of the screw shell 11 may be arranged to straddle the parts 13 and 14 at a point where there are openings 60 and 61 in the base 13 and cover 14 respec 95 tively Thus, a strip 62 may be fitted through the slots 59 in the tabs 58 as well as through

the openings 60 and 61 in the housing parts Finally, the free end of strip 62 is bent or twisted to complete the 100 assembly and finally hold all of the parts in assembled relation An end 63 of the strip 62 is bent at a right angle and provided with a tapped opening 64 for receiving the terminal screw 65 so that a 105 second lead wire (not shown) may be connected to the switch mechanism for completing the circuit through the switch by way of strip 62 and shell 11. It will be appreciated by one skilled in 110 this art that a simplified design is provided for a ratchet-type switch mechanism having a rotary contact member with edgewise blades for making and breaking contact with the fixed contacts of the 115 switch mechanism Because of the use of these edgewise blades, it is possible to provide narrow grooves between the fixed contacts so that when the blades are seated therein, the clearances between the blade 120 and the side walls of the grooves are so slight as to prevent an electrical arc from spreading and burning the switch parts. It is this feature which has brought about the new and unobvious result of 125 extinguishing the are and extending the life of the switch as well as making it possible to obtain a higher electrical rating for the switch at a minimum cost. A second important feature of this 130 784,978 invention is the unique manner of supporting the fixed contact 17 within the base by utilizing the hook member 23 and ledoe 24 which co-operates with the apertured boss 55 in the cover 14 to hold the terminal end 19 firmly in place in the switch housing Also, the adjustable torsion spring means is another improvement which contributes to the high quality of this device Likewise, the manner in which the simple strip 62 is used to finally assemble this switch mechanism as well as to provide a terminal connection is a uni(que feature of 15this present invention. While the rotary switch of this invention has just been described as combined with a lamp socket it should be appreciated that this ratchet-type switch mechanism has general utility in the switch art It could he used in a feed through switch which may be used to provide a switch external to a piece of portable electrical apparatus by incorporation of the switch in anl electrical flex leading to such apparatus.

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* GB784979 (A)

Description: GB784979 (A) ? 1957-10-23

A transportable desk, office table or the like


PATENT SPECIFICATION Date of Application and filing Complete Specification: April 3, 1956. 784,979 No 10084/56. FIE'S Application made in Germany on April 14, 1955. / Complete Specification Published: Oct 23, 1957. Index at acceptance:-Class 52 ( 3), H( 5 E 1:15:21), O ( 22:25). International Classification:-A 47 b. COMPLETE SPECIFICATION A Transportable Desk, Office Table or the Like We, SIEMAG FEINMECHANISCHE WERKE G.m b H, a Joint Stock Company organised under the Laws of Germany, of Eiserfeld/ Sieg, Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to a desk, office table or the like in particular a book-keeping desk or table for a typewriter and a calculator. Desks are already known which are formed from a closed box in which the side walls of the box may be moved up and down on hinge axes These can be used as desks, but they differ in construction from the usual form of office desk since they do not have two side parts or pedestals connected by means of a writing board, a form which has proved suitable for the location of office materials. According to this invention, there is provided a transportable desk, office table or the like consisting of several separately-transportable components one of which constitutes one side pedestal of the desk and has a hinged side wall which may be raised to provide a writing board extending to and resting on another side pedestal formed by the other components placed one on another, and at least one of said components being adapted to house office machinery

and/or office materials for their transport. The hinged side wall may have at its free end a pivotable flap which is insertable in corresponding pockets located on the components forming the other side part of the desk. There are compartments and holders provided in the said components for receiving and transporting the articles necessary for a book-keeping equipment. One embodiment in accordance with the invention will be explained in more detail with reference to the accompanying drawings and in the present case it relates to a bookkeeping machine table on which decentralised book-keeping work is carried out As a book-keeping equipment a known combination of typewriter and calculating machine may be used From all the book-keeping 50 processes, in order to be able to evaluate the results centrally, perforated tapes are employed which are transmitted in known manner to a central office either directly or via teleprinter This type of desk is useful 55 mainly for building sites, army units and service stations whose location frequently changes. Fig 1 shows the separate transportable components capable of being formed into a 60 desk; Fig 2 is a perspective view of the assembled desk; and Fig 3 is a perspective view of the largest component with a hinged side part shown 65 open. As shown, the components 1, 2, and 3 are each provided with a handle 4 for easier handling during transport. A side-wall 5 of the box 1 is capable of being 70 hinged upwards, and has at its free end a hinged flap or strut 6 (Fig 3) which, on the assembly of the three components into a desk is inserted into corresponding pockets 7, 8 (Fig 2) located respectively on the com 75 ponents 2, 3 When the desk is put together as shown in Fig 2, the component 1 serves as the left-hand side part of the desk whilst the right-hand side part is formed by placing the components 2 and 3 one on the other 80 The two side parts are connected together by means of the said upwardly-hinged side wall 5 with the flap 6, by means of which flap the components 2 and 3 are also kept in position relatively to one another The parts 1, 2 and 85 3 are in the form of hollow boxes, the box 1 constituting a cupboard divided into compartments and closed by the flap 5. In working with a combination consisting of typewriter and calculating machine, it has 9 t 784,979 been found advisable to arrange the calculating machine 9 a little lower than thetypewriter 10 as this facilitates the work of the operator The right-hand side part consisting of the components 2 and 3 placed one on the other and on which the calculating machine 9 is located is therefore slightly lower than the left-hand side and the extending flap 5.

Compartments for receiving the typewriter 10, the calculating machine 9, a card box 11, and one or more typewriter carriages 12 are provided during the transport of the desk from place to place whilst in box 2 or 3 a converter for decoding particulars recorded in a punched card or punched tape system are located, and in the box 3 or 2 a tape perforator is located for the production of a punched record of the booked entries The devices are permanently located in their respective housings. The location of the decoder and the tape perforator in two separately transportable boxes appears therefore to be advantageous, since these devices as is known are extremely susceptible to trouble and thus in case of need either device can easily be changed without needing to change the other also. The plug contacts or sockets for the electrical connection of the devices located in the respective compartments are arranged countersunk and are covered over with a protective flap so that in transport they are not disturbed and damaged. It is of course possible to use the desk according to the invention also for other work carried out with other apparatus The location in the components of the appropriate devices for such other work must then be effected correspondingly.


* GB784980 (A)

Description: GB784980 (A) ? 1957-10-23

Continuous filtration apparatus


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BE547544 (A) DE1041924 (B) FR784980 (A) FR1153176 (A) BE547544 (A) DE1041924 (B) FR784980 (A) FR1153176 (A) less Translate this text into Tooltip

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COMPLETE SPECIFICATION Continuous Filtration Apparatus We, AKTIEBOLAGET BOFORS, a Swedish Company, of Bofors, Sweden, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to filtering apparatus for continuous filtering with continuous feed of material to be filtered and continuous removal of filtrate and separated material. The apparatus according to the invention comprises a flat circular horizontal filter plate; spreading means to spread said material and comprising a hollow shaft having its axis substantially perpendicular to the filter plate at the centre thereof being mounted for rotation about said axis and having an outlet adjacent the filter plate to direct material to be filtered generally radially thereover; a scraper knife fixed to the shaft and extending radially therefrom forward of said outlet (referred to the direction of normal rotation); removing means for material not passing the filter comprising a ramp extending from the scraper knife, a horizontal platform above the level of the filter plate to receive the material moved by the scraper knife and passing up the ramp and a pusher arranged to swing on rotation of said shaft whereby to move material on the platform to a discharge point; a vacuum chamber communicating with the underside of the filter plate over the whole area thereof; and a loosening device comprising an arm rotatable coaxially and synchronously with the hollow shaft and providing an air chest mounted in the vacuum chamber and adapted to be connected to a pressure source, a perforated diaphragm on the air chest and a frame on the diaphragm surrounding the holes therein and spaced inward of its secured edges, said frame contacting the underside of the filter plate on supply of pressure air to the chest

whereby air is forced through said plate over a sector thereof forward of the scraper knife. At an appropriate angular distance from the scraper blade there will generally be provided a device for washing the separated material, which rotates at the same angular speed. The vacuum under the filter plate enables quick removal of the filtrate and the washing liquid, so that after rotation of the spreading device by less than 360" the separated material will be so dry that it can continuously be collected and transported away from the filter plate whereby the surface thereof is again ready to receive material to be filtered. One form of apparatus according to the invention will now be described by way of example with reference to the accompanying drawings in which: Fig. I is a diagrammatic vertical section of the apparatus; and Figs. II and HII are diagrammatic sectional views, greatly simplified, taken on the lines A-A of Fig. III and B-B of Fig. I respectively. Referring to the drawings, material to be filtered is supplied to a plane, circular horizontal filter plate 1 by means of a rotating radially directed diffusing nozzle 2 fixed to a scraping knife 8. The material is fed to the opening 2 through a hollow rotatable shaft 3, which is coaxial into the plate 1 and serves to support the knife 8, ramp 9 and a horizontal platform 10. A tube 4 is fixed to the shaft 3 at an appropriate angular distance from the knife 8 and extends radially from the shaft. The tube 4 is closed at its outer end and, over its entire length, it is provided with small holes whereby it forms a washing device for the material remaining on the filter plate 1. The tube 4 opens out into a channel 5 in the shaft 3; washing liquid can be fed through a connection piece 19 into the channel and thence to the washing device. A vacuum chamber 6 is connected to the filter plate to communicate with the entire bottom surface thereof and the filtering speed can be fixed so that after less than 360D angular movement of the diffusing nozzle 2 the material retained on the filter plate 1 is washed and drained off, and ready to be moved away. The vacuum chamber 6 is connected by a tube 7 to a pumping device intended to maintain the vacuum in the chamber and to remove the filtrate collected therein. The knife 8 for scraping retained material from the filter extends radially over the filter immediately in front of the diffusing nozzle 2, and consists of a plate bent at an angle and formed as a scraper which, on the rotation of the shaft 3, moves immediately above the upper surface of the filter plate 1 and moves the material thereon up the ramp 9 to the horizontal platform 10 which is joined to the knife. The platform is circular and extends about 300 from the front edge of the scraper, and from this platform the material is removed through an

opening 11 (see Fig. III) by a pusher blade 12 which is reciprocated over the platform by a cam 13 on the shaft 3. It may sometimes be difficult to loosen retained material from the filter plate and to facilitate loosening a loosening device 14 is provided under the filter plate. This device supplies compressed air through a limited portion of the filter plate and the air pressure beneath the material retained on the plate loosens it therefrom so that the knife can more easily scrape off the material in the way described above. The device 14 comprises a rotatable radially extending arm 15 providing an air chest within the vacuum vessel and carrying a thin membrane 16 provided with fine holes. On the membrane and spaced inwards of its secured edges is mounted a frame 17 surrounding the holes, which bears upwards against the bottom surface of the filter plate. Pressure air is supplied through a channel 18 and causes the membrane 16 to bulge upwardly and thereby press the frame against the bottom of the filter plate, the air passing through the holes going through the filter and loosening the material from the top of the filter. The frame 17 is located in front of the knife 8 and rotates coaxially and synchronously with it as indicated by the chain lines in Fig. I. The filter has the following advantages: The feed of material to be filtered takes place by its dropping freely, and this, together with the fact that the diffusing nozzle 2 rotates enables the material to be applied evenly to the filter surface. The distribution over the filter surface can be improved by fitting the horizontal portion of the knife 8, which controls distribution of the material to be filtered, with guide bars or other guide means. The filter surface is stationary, plane and horizontal, which makes even distribution possible. It also enables the thickness of the material on the filter to be chosen exclusively with consideration to what is appropriate for good filtering, and above all, good washing while using the least possible quantity of washing liquid. Neither of these two advantages can be obtained with a rotating drum filter. The filtrate is removed downwards through fixed connections, which thus do not involve any sealing problems. The feed of washing liquid can take place at any desired angular position in relation to the feed of material to be filtered. What we claim is: 1. Filtering apparatus for continuous filtering with continuous feed of material to be filtered and continous removal of filtrate and separated material, comprising a flat circular horizontal filter plate; spreading means to spread said material and comprising a hollow shaft having its axis substantially perpendicular to the filter plate

at the centre thereof being mounted for rotation about said axis and having an outlet adjacent the filter plate to direct material to be filtered generally radially thereover; a scraper knife fixed to the shaft and extending radially therefrom forward of said outlet (referred to the direction of normal rotation); removing means for material not passing the filter comprising a ramp extending from the scraper knife, a horizontal platform above the level of the filter plate to receive the material moved by the scraper knife and passing up the ramp and a pusher arranged to swing on rotation of said shaft whereby to move material on the platform to a discharge point; a vacuum chamber communicating with the underside of the filter plate over the whole area thereof; and a loosening device comprising an arm rotatable coaxially and synchronously with the hollow shaft and providing an air chest mounted in the vacuum chamber and adapted to be connected to a pressure source, a perforated diaphragm on the air chest and a frame on the diaphragm surrounding the holes therein and spaced inward of its secured edges, said frame contacting the underside of the filter plate on supply of pressure air to the chest whereby air is forced through said plate over a sector thereof forward of the scraper knife. 2. Apparatus as claimed in Claim 1, comprising a washing device including a channel in said rotatable hollow shaft, inlet means to supply washing liquid to the channel, and a perforated tube fixed to the shaft, closed at its outer end and communicating with the channel, the angular position of the tube being adjustable in relation to the member providing said scraper knife. 3. A filtering apparatus substantially as herein described with reference to the accompanying drawings.

* GB784981 (A)

Description: GB784981 (A) ? 1957-10-23

Improvements in or relating to metal working machines


PATENT SPECIFICATION

Date of Application and filing Complete Specification: May 17, 1956. 784,981 No 15452/56. Complete Specification Published: Oct 23, 1957. Index at acceptance:-Class 83 ( 4), E( 1:10 D 1). International Classification:-B 23 k. COMPLETE SPECIFICATION Improvements in or relating to Metal Working Machines We, F J EDWARDS LIMITED, a British Company, of 359-361, Euston Road, London, N.W 1, and GEORGE MICHAEL HAYWARD, a British Subject, of the Company's address, do hereby declare the invention for which we pray that a patent may be granted to us and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to sheet metal working machines, and in particular to presses for the bending or folding of metal sheets to form boxes, pans, or other articles of a similar configuration. Presses of this kind normally comprise a beam which carries a ram die to co-operate with a female die carried by a second beam which is usually part of the pedestal of the press The metal sheet is interposed between the co-operating die members and these are moved together to cause the sheet to be folded to a predetermined angle or bent about a predetermined curve along the line of the dies. The dies are then separated and the folded or bent metal can be removed from the press or moved into position for further formation. Such machines, however, normally suffer from the disadvantage that trunk sections or tubes of rectangular or other cross-sections cannot easily be withdrawn from the machine after forming without distorting them and that deep trays, that is trays having high side walls and open top boxes cannot be formed since the top dies are neither deep enough nor split into sections. It is an object of the present invention to provide a sheet metal press which is not subject to these limitations. According to the present invention a sheet metal working press is provided in which a pair of members carrying co-operating dies are moveable upon guides towards and away from one another to fold and bend sheet metal disposed therebetween, wherein one of said members may be disengaged from one of said lPrice 3/6 l guides and moved relative to the other member to allow work to be removed from the press. Conveniently the moveable member may be pivotally supported upon one of the guides 50 for movement in a plane perpendicular to the direction of the co-operating movement between the members and engageable with the other of said guides to align it with the other of said members 55 By this means a press is provided upon which sheet

metal articles of regular or irregular cross-section, and of trunk form, may be formed and may be removed from the press after formation by disengaging the 60 moveable member from one of the guides and pivoting it about the other of the guides into a suitable position where an article of trunk section may be removed in a direction parallel to the length of the member 65 The moveable member may be either of the co-operating members which carry the dies, but it is generally more convenient to make the upper beam the moveable member since the lower beam of the machine is usually an 70 integral part of the pedestal frame It will be appreciated however that in the cooperating movement which brings the dies together to bend the metal the upper beam may move downwardly or lower beam may 75 move upwardly, or both may move towards each other. In addition the separation between the die carrying beams or members may be increased or decreased to accommodate dies of different 80 sizes without varying the stroke of the machine appreciably. In order that the invention may be clearly understood some embodiments will now be described by way of example with reference 85 to the accompanying diagrammatic drawings in which:Fig 1 is a front view of the machine according to the invention; Fig 2 is a section taken on the line 11-II; 90 X< p 784,981 and Fig 3 is a view from the front of the machine taken in section to show the construction of the working parts thereof. The machine consists of a pedestal base which is totally enclosed, and which contains the frame upon which the machine is supported and the working parts thereof, and from the ends of which there extend upwardly cylindrical guide members I at each end of a lower beam 2 carrying a female die 3, the guides carrying an upper beam 4 upon which are supported dies 5. A driving motor 6 which may be an electric squirrel cage motor is controlled by a suitable motor controller 7 upon the front of the machine pedestal A pulley or pulleys 8 transmit the motor drive by means of Vbelts 9 to a heavy fly-wheel 11 The fly-wheel is mounted upon a shaft 12 carried by double bearings 13 and 14 and connected at the end remote from the fly-wheel to a double-acting clutch and brake 15. The clutch is operated by a system of levers indicated at 16 and connected to an operating treadle bar 17 external of the machine pedestal The treadle bar is biased into its uppermost position and in this position the clutch is disengaged and the brake is engaged so that the upper beam cannot move When the treadle is depressed the brake is disengaged and the clutch engaged to operate the press By operating the treadle bar carefully at an intermediate position both clutch and brake can be maintained lightly in engagement so that the

moving parts of the machine may be very gently inched. The shaft 18 carrying the drive from the combined press and brake enters a worm reduction unit 19 from which extends a shaft 21 carrying a pinion 22 This engages a pinion 23 upon a cross drive shaft 24 journalled in bearings 25 The drive shaft 24 carries eccentrics 26 by means of which the top beam may be vertically reciprocated. The guides which serve to keep the top beam accurately aligned comprise sleeves 27 rigidly mounted in the pedestal frame, in. which tubular members 28 are vertically reciprocable, the members 28 being prevented from rotating relative to the sleeves 27 by a key 29 sliding in a key-way 31 in the sleeves. The tubular members 28 are screw threadably connected to concentric shafts 32 which extend downwardly from the lower end from the members 28 to be rigidly longitudinally engaged within a seating 33 which however will allow the shafts 32 to rotate about their central axis The seatings 33 are connected to the eccentrics 26 carried by the shafts 24 by means of a cylindrical sleeve 34 engaging about the eccentrics 26 carried upon the shaft 24, and rigidly connected to the seating. An external handle or knob 35 is provided to rotate a control shaft 36 carrying a worm 37 appropriate to each of the vertical guides, which worms engage pinions 38 keyed to the shafts 32 to rotate these By rotating the shaft the effective length of the shaft 32 and the tubular members 28 may be changed to 70 vary the height of the beam to allow for the insertion of different sized dies In practise the dies are fitted in the upper and lower beams with the guides extended to such an extent that the dies cannot be brought right 75 into contact The machine is then inched until the upper beam is in its lowermost position, that is at the bottom of its operating stroke, at which point the adjusting handle is manipulated to lower the top beam until the 80 separation between the aperture faces of the dies is exactly the thickness of the metal sheet with which the machine is to be used. The upper beam is carried by the upper ends of the tubular members 28 At one end 85 the mounting is in the form of double-thrust bearings 39 which allow the beam to be pivoted about the tubular member in a horizontal plane The bearings may be held in place by capping nuts 41 and 42 on top of 90 which are fastened a sealing plate 43 The other end of the beam is provided with a disengageable coupling This may be in the form of a half-cylindrical member 44 to engage about the tubular members 28 and to be 95 held in place by the latch The upper face 45 of the half-cylindrical member abuts the lower face 46 of a thrust cap 47 screw threadably engaged in the upper end of the tubular member 28 so that the driving force 100 applied to the top beam is not transmitted by the latch which maintains the halfcylindrical member in

position about the tubular member The latch may comprise a spring-urged plunger 48 to engage with in an 103 aperture 49 provided therefor in the tubular member 28 and having a knob 51 or lever by means of which the latch may be disengaged against the tension of the spring 52 to allow the half-cylindrical member to be moved away 110 from the tubular member to facilitate the removal of a work piece from the machine. The top beam 4 which may be machined from steel plate, is provided with suitable means, which may be of conventional form, 115 by which the upper dies 5 may be secured thereto The upper dies will normally be in the form of a number of sections each a fraction of the total length of the top beam so that short internal folds or bends may be 120 made within a partly formed box or other section. The female die 3 which will normally be made in one piece is mounted, again by conventional means upon the second beam or 125 bed of the machine Both dies or sets of dies may readily be interchanged to provide for the folding of metal sheet through different angles or the bending of sheet about different radii 130 784,981 In use, where the machine is to be used for making shallow trays or for bending sheet metal through a predetermined angle or curve along one or two pre-determined lines, it may be used in a purely conventional manner In other words the sheet is located in the correct position relative to the dies, firmly supported in this position, when by clepressing the treadle bar the press is operated to bend the sheet The sheet is then withdrawn by sliding it between the opened dies. Where deep trays, open-topped boxes or trunk sections are required, however, these are formed in exactly the same fashion, and if after formation they are of a shape or size which does not allow them to be removed from the press by sliding between the opened dies without distorting the pressing, the top beam is unlatched and swung horizontally about its pivot into a position where the pressing may be removed without difficulty and without distortion The beam is then returned to its normal position in which it is retained by the latch.


* GB784982 (A)

Description: GB784982 (A) ? 1957-10-23

Improvements relating to coal winning apparatus


PATENT SPECIFICATION Date of Application and filing Complete Specification: June 1, 195 Application made in Germany on June 7, 1955. Complete Specification Published: Oct 23, 195 784,982 No 17016156. 6. 7. Index at acceptance:-Class 68 ( 1), F( 2:4 B). International Classification:-E 21 c. COMPLETE SPECIFICATION Improvements relating to Coal Winning Apparatus We, DEMAG AKTIENGESELLSCHAFT, a German Company, of Wolfgang-Reuter-Platz, Duisburg, Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: With soft and medium coal, scraper boxes have been found to be quite effective When scraper boxes are, however, applied to hard coal, the cutters of the boxes fail to penetrate the coal, only splintering off fine particles of coal without any appreciable winning efficiency being achieved. Attempts have been made to increase the force exerted on the cutters, but this renders it necessary to provide the thrust devices acting on guide rails or the like to force the scraper boxes against the working face of a stronger construction Even this is insufficient, for it would then also be necessary for the scraper boxes to be of a much stronger construction Apart from the high expenditure in material and costs, there is also the danger of the boxes, being considerably heavier, digging themselves into the floor which would make it necessary to take special preventive measures. Other attempts have been made to force the cutters to penetrate hard coal by subjecting the cutters to impacts, pulsations, vibrations or the like Apart from the substantially increased expenditure involved, means of this kind fail to attain the object and a practicable

solution of the winning of hard coal by scraper boxes has hitherto not been found. It is among the objects of the invention to provide an apparatus by which hard coal cah be won by means of scraper boxes. In accordance with the invention, a precutting tool, the cutter or cutters of which is or are subjected to a considerably higher pressure than are the cutters of a scraper box lPrice 31 P-ce 4 S 6 ( 4 or boxes, is provided in front of each of the scraper boxes at a distance sufficient to ensure that the total thrust acting on the precutting tool and the adjacent scraper box is effected by different thrust devices for facing 50 the scraper box and cutting tool against the coal face The distance between the precutting tool and the adjacent scraper box is not less than the distance between two adjacent thrust devices 55 While the cutters of the adjacent scraper box extends practically rip the entire height of the scraper box, the cutter or cutters of the pre-cutting tool extends only over a small portion of this height so that the pressure on 60 the cutter or cutters of the pre-cutting tool is several times higher than the pressure exerted on the cutters of the adjacent scraper box for the same pressure being exerted on the tool and the scraper box Thus the cut 65 ter of the pre-cutting tool penetrates into the coal, cutting into it a cleft and thereby loosening the seam or vein so that the succeeding cutters of the adjacent scraper box, though exerting a lower pressure on the face 70 than the cutter of the pre-cutting tool, can get the coal under the improved conditions then prevailing. It is of advantage to use stepped cutters of the pre-cutting tool which, in addition to 75 displaying a greater sturdiness, also affords the advantage of penetrating to various depths depending upon the resistance encountered in the direction of thrust, so that the depth of penetration is, as it were, auto 80 matically controlled. The pre-cutting tool may also be constructed as a scraper box It is then advantageous to divide up the work, for example, by allowing the preliminary cutting tool to 85 transport the coarser lumps of coal only, while the main box picks up the fine coal. This may, for example, be effected by providing the hinged rear wall to terminate at a determined distance above the floor rather 90 784,982 than allow it to extend down to the floor so that any lumps below the level of this rear wall are left behind. The pre-cutting tool may be provided in the cable at either side of a scraper box, that is to say, in front or to the rear thereof, so that work in either direction is facilitated. According to the invention, therefore, hard coal can be won by means of scraper boxes without the disadvantage of having to use separate strong thrust devices and without having to provide scraper boxes of

heavy construction The work can be carried out with conventional scraper box apparatus, it being merely necessary to add the pre-cutting tools It is an advantage that such apparatus so adapted for the winning of hard coal can, when changing over to softer coal, be used without pre-cutting tool or tools. Thus by means of the invention, the thrust devices are put to better use than has hitherto been the case, as the number of effective thrust devices may be twice or even three times that hitherto used with scraper boxes. One construction of a coal winning apparatus is illustrated in the accompanying drawings, in which: Fig 1 shows a partial plan of the apparatus; and Fig 2 is a section on the line II-II of Fig 1. The cylinders of hydraulic or pneumatically-actuated thrust device 3 are disposed between and abut against guide rails 4 and prop 2 provided in the working 1 Scraper boxes 5 are pulled to and fro by cables 6 and 7, the boxes being guided by the rails 4, which are independent of each other. The boxes 5 are provided with cutters 8 and 9 by means of which they strip off coal from a seam 10 during the forward and return strokes while being forced by the thrust devices 3 by means of the rails 4 against the face 10 The coal obtained is fed in known manner by the scraper boxes 5 provided with movable rear flaps, to the discharge end of the apparatus To this extent the apparatus is known. In accordance with the invention, a precutting tool 12 which is provided with a cutter 13 is inserted in the cable 6 at such a distance from the adjacent scraper box that the total thrust on the box and the total thrust on the tool is effected by different thrust devices 3 The cutter 13 is rotatably mounted about a vertical shaft 15 on the body of the tool 12, movement about said shaft being limited by a stop 14 on said body of the tool 12 during movement of the tool 12 in one direction. As shown in Fig 2, the cutter 13 cuts a cleft 16 into the seam 10, thus loosening the coal to be won so that the scraper box which follows the pre-cutting tool 12 can get the coal with its cutters 8 and during the return stroke the cutters 9 can penetrate the coal at the entire depth of the cut cleft, the cutter 13 being lifted by frictional resistance, or by spring means or the like, from the abutment 14, and thus being prevented from becoming 7 ( O prematurely blunt by being dragged over the coal. Instead of a single cutter, several cutters each of correspondingly smaller vertical extent than the single cutter of the pre-cutting 75 tool may be provided which engage the coal at various positions or, if occasion arises, at various levels.

It will be understood that it is desirable that the pressure exerted on the cutter or 80 cutters 13 is substantially higher than that exerted on the main cutters 8, in order to ensure that the pre-cutting blade or blades can be forced into extremely hard coal The distance between the pre-cutting tool and the 85 scraper box should be not less than the distance between adjacent thrust devices 3.
