US3390462A - Carriage-type drawing apparatus - Google Patents

Description

July 2, 1968 FAUL ET AL 3,390,462

CARRIAGE-TYPE DRAWING APPARATUS Filed April 24, 1967 5 Sheets-Sheet 1 unar/g.

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Inventor:

Thomas L. Paul and Tu an Viuar 3: M44- .HBH'TI' Y I /Hkom July 2, 1968 T. L. FAUL--ET AL 3,390,462

CARRIAGE-TYPE DRAWING APPARATUS Filed April 24, 1967 3 Sheets-Sheet 2 lnvenlor: [mamas L. Tau! and To? an (/iwu July 2, 1968 'r. L. FAUL ETAL CARRIAGE-TYPE DRAWING APPARATUS 3 Sheets-Sheet 5 Filed April 24, 1967 lnvenlar: Thomas L. Fan and Tu'rqw V uu 3Y= Wul- H'ui'um M nu- United States Patent 3,390,462 CARRIAGE-TYPE DRAWING APPARATUS Thomas L. Faul, Skaneateles, N.Y., and .Iurgen Vieser,

Lahr, Black Forest, Germany, assignors to Albert Nestler A.G., Lahr, Black Forest, Germany Filed Apr. 24, 1967, Ser. No. 633,099 Claims priority, application Germany, Apr. 28, 1966, N 28,458, N 28,459, N 28,461 15 Claims. (Cl. 33-79) ABSTRACT ()F THE DISCLOSURE A carriage-type drawing apparatus which is designed so as to permit the carriage of the drawing head to be very easily adjusted to and locked at any point of the guide rail by a very simple device and which is also provided with a simple device for locking the counterweight in a fixed position to prevent it from damaging the apparatus during shipment.

Summary of the invention The present invention relates to a carriage-type drawing apparatus which is provided with a guide rail extending parallel to a drawing board for supporting and guiding a carriage.

It is an object of the invention to provide such an apparatus with a device which permits the drawing head to be very easily adjusted to any position along the length of a guide rail and to be locked in such a position for a drawing operation.

A feature of the invention for attaining this object consists in the provision of a locking device which is connected in such a manner to a bracket which is pivotably mounted on the carriage and carries the drawing head that when the drawing head is lifted off the drawing board, the locking device will be released so that the carriage may then be easily shifted along its guide rail.

Another object of the invention consists in providing such a carriage-type drawing apparatus with suitable means which during a shipment of the apparatus are adapted to prevent a counterweight for the carriage from being thrown back and forth against the inner walls of the hollow rail in which the counterweight is guided, and which thus prevent the counterweight, and especially the rollers of a roller-mounted counterweight, from being damaged during shipment.

Another feature of the invention therefore consists in providing the apparatus with a very simple locking device for securing the counterweight in a fixed position within the hollow guide rail so as to prevent it from moving therein during a shipment of the apparatus. This locking device consists of at least one locking screw in a tapped bore in the counterweight and of a bore in a wall of the guide rail through which a screw driver may be inserted for turning the locking screw so as to clamp the counterweight firmly against an inner wall of the guide rail.

It is another object of the invention to mount the rollers of the counterweight so that the movements of the counterweight will be as silent as possible.

Another feature of the invention for attaining this last object consists in mounting the rollers on the counterweight by resilient, sound-absorbing means so that, when employing, for example, rollers of plastic, the counterweight may be moved along the inside of the guide rail without making any noise.

3,3%,462 Patented July 2, l9fi8 Another feature of the invention consists in rotatably mounting a pair of these rollers on the ends of an axle which is then inserted into a transverse recess in one side of the counterweight and is clamped in this recess by means of at least one resilient element.

It is a further feature of the invention to provide the axle for each pair of rollers at the center of its length with a flange which accomplishes two purposes, namely, to serve as a stop to prevent the axle from shifting in its axial direction by fitting into a corresponding recess in the counterweight, and to serve as a means for connecting the cable or cables to the counterweight which connect the latter to the carriage carrying the drawing head. For the last-mentioned purpose, the flange on the roller axle is provided with recesses in which the ends of the cables are secured. In connection with the feature of the invention of mounting the axle in the counterweight by means of a resilient connecting element, the additional advantage is attained by connecting the cables to the axle flange that, due to the resilient element, the cables may be given a resilient tension which is important for a proper operation of the counterweight.

The above-mentioned as well as numerous other features and advantages of the present invention will become more clearly apparent from the following detailed description thereof which is to be read with reference to the accompanying drawings, in which:

FIGURE 1 shows an elevation of a drawing board with the carriage-type drawing apparatus according to the invention;

FIGURE 2 shows an enlarged rear view of the carriage carrying a drawing head;

FIGURE 3 shows a cross section which is taken along the line IIIIII of FIGURE 2;

FIGURE 4 shows an enlarged elevation of the counterweight according to the invention, wherein one of the roller axles is removed and shown separately from the counterweight;

FIGURE 5 shows a side view of the counterweight according to FIGURE 4;

FIGURE 6 shows a cross section which is taken along the line VIVI of FIGURE 5;

FIGURE 7 shows, partly broken away and in section an enlarged view of the central part of one of the axles carrying the rollers of the counterweight;

FIGURE 8 shows a cross section which is taken along the line VIII-VIII of FIGURE 1 of the second rail support;

FIGURE 9 shows a cross section which is taken along the line IX-IX of FIGURE 8; while FIGURE 10 shows a cross section which is taken along the line XX of FIGURE 9.

The carriage-type drawing apparatus according to the invention as illustrated in the drawings comprises a first guide rail 3 which is connected to a drawing board 1 and provided with rail tracks on which the rollers of a first carriage 7 are movable. Carriage 7 carries a second guide rail 9 with a pair of opposite rail tracks 23 for the rollers 5 of a second carriage 11. By means of a connecting bracket 15 which is pivotable about a pair of pivot pins 13 extending parallel to the second rail 9, the second carriage 11 is connected to a drawing head 17 which is either rigidly connected to the bracket 15 or so as to be pivotable about an axis extending parallel to the axis of the pivot pins 13. Both rails 3 and 9 form sections of a suitable length of the same hollow rail stock of a cross-sectional shape as shown in FIGURE 8.

As shown particularly in FIGURES 2 and 3, the second carriage 11 is provided with a locking device which consists of a lever 12 which is pivotable about the axis of a pivot 12' which extends at right angles to the plane of the drawing board 1. This lever 12 carries a brake shoe 14 which is adapted to be applied against the second guide rail 9 and is acted upon by a compression spring 16 which tends to lift the brake shoe 14 off the second rail 9 so as to release the locking device.

The connecting bracket is provided with a control device for operating the brake lever 12 of the locking device in the second carriage 11. This control device has a control lever 83 which is pivotable on a pivot 18 from a releasing position to two different locking positions and carries a cam plate 20 which is opcratively associated with the brake shoe 14- when the drawing head 17 in its operative position rests on the drawing board. The control lever 38 is acted upon by a tension spring 22 which tends to return the lever to its releasing position. The peripheral surface of cum plate 2-3 is designed so that, when lever 38 is in its first locking position and cam plate 20 engages upon the brake shoe 14, there will be no self-locking action so that, if the draftsman takes his finger off the control lever 88, this lever will be returned by the return spring 22 to its releasing position. If, however, the control lever 88 is pivoted to the second locking position, the friction between cam plate 20 and brake shoe 14 will produce a self-locking action which prevents the control lever 88 from returning automatically to its releasing position. In the particular embodiment as illustrated, the control lever 88 and the cam plate 24} consists of a single piece of material and are pivotably mounted in such a manner on the connecting bracket 15 that, when the drawing head is lifted off the drawing board by pivoting the bracket 15 about the pivot pins 13, the cam plate 2!) will also be lifted off the brake shoe 14 so that the latter will then be lifted off the guide rail 9 by the compression spring 16 and the locking action will thereby be discontinued. The control lever 88 will then at the same time be pivoted back to its releasing position by the return spring 22 so that, when the drawing head 17 is thereafter layed back upon the drawing board, the carriage 17 will not be locked.

From the above description it is therefore evident that the brake shoe 14 and the cam plate 20 form coupling elements for connecting the control device comprising the lever 88 and the cam plate 29 to the locking device comprising the brake shoe 14.

As illustrated in FIGURES 4 to 8, the inside 59 of the second guide rail 9 contains the counterweight 61 which is provided near both ends with opposite lateral recesses 2 in which two pairs of rollers 76 are located. Each pair of these rollers 76 is rotatably mounted on the ends of an axle 176 which is inserted into a transverse recess 158 in the lower side of the counterweight 61 and is clamped in a fixed position therein by a pair of resilient rings 16% of rubber or plastic which are fitted upon the axle 176.

Each axle 176 is further provided with a central flange 162 which has a width in accordance with the width of a cutout 164 in each end of the counterweight. When the two axles 176 are inserted into the transverse recesses 158 of the counterweight and are clamped therein by the resilient rings 160, the flanges 162 fit tightly into the cutouts 164 and act as stops for preventing the axles from shifting in their axial directions.

Flange 162 on each axle 176 is provided with two adjacent slots 166 which extend at right angles to the axis of the axle from one side of the peripheral surface of the flange approximately to a diametrical plane of the flange. Each flange 162 is further provided with a pair of socket bores 168 which extend to the bottom end of the slots 166 and are adapted to receive thickened end portions 179 on the ends of a pair of cables 63 when these cable ends are inserted into the slots 166. The thickened end portions 170 of the cables in the socket bores 168 then secure the cables in the slots 166. The other ends of the two cables 63 are secured in the same manner to the flange 162; of the other axle 176 so that the counterweight 61 connects the opposite ends of each of the two cables 63 to each. other. These two cables then extend over a pailof guide pulleys, not shown, which are mounted on the ends of the second guide rail 9, and the strands of cables 63 which extend along the rear outer side of the second guide rail 9 are connected in a conventional manner to the second carriage 11.

The manner of mounting the axles 176 in the recesses 158 in the counterweight 61 by means of resilient rings 166 permits a very simple construction of the counterweight, especially if each of these axles is provided with a central flange 162. These resilient rings also insure a practically noiseless run of the counterweight 61 and permit the cables 63 to be given a resilient tension. When the drawing board is obliquely inclined or in a horizontal position, the guide rollers 76 of the counterweight 61 rest upon the rear wall 4 of guide rail 9, as shown in FIGURE 8, which then serves as a runway for these rollers.

As shown particularly in FIGURES 9 and 10, the counterweight 61 is further provided with a pair of tapped bores 6 into which locking screws 3 are screwed each of which has a head 16 with a slot 24 for the insertion of a screw driver. The ends 26 of the tapped bores 6 facing the runway 4 for the rollers 76 are recessed to permit the screw heads 10 to be inserted therein. The recessed end 26 of each of these bores has such a depth that, when the respective screw 8 is screwed into the bore 6 until the head 11) engages upon the bottom 26' of the recess 26, the free end of the shank 8 of the screw and the head 10 will be flush with the opposite sides of the counterweight or project only so slightly therefrom that they cannot engage with the adjacent walls of guide rail 9. Screws 3 are in this position, as shown at the lower part of FIGURE 10 when the drawing apparatus including the counterweight 61 is in operation.

The rear wall 4 of guide rail 9 which forms the runway for the rollers 76 is provided within its central longitudinal axis with a pair of bores 28 which are spaced at the same distance from each other as the bores 8 in the counterweight 61 so that when the latter is shifted to the proper position, the bores 33 and 28 may be placed in accurate alignment with each other. These bores 28 are conically enlarged toward the inside of the guide rail and made of a diameter so as to form conical seats, for the conically reduced free ends 32 of the screw heads 19, as shown at the upper part of FIGURE 10.

The side of the counterweight 61 opposite to the wall 4 of guide rail 9 is provided with four projections 34 which project further from this side than the rollers 76.

If the drawing apparatus as previously described is to be packed for shipment, the second carriage 11 which is connected to the counterweight 61 by the cables 63, is shifted along the guide rail 9 to a position in which the screw heads 10 coincide with the bores 28. A screw driver is then inserted through the bores 28 into the slots 24 in the screw heads 10 and screws 3 are then turned until their ends 32 engage into the bores 28 and shift the counterweight 61 toward the wall of guide rail 9 opposite to the Wall 4 until the projections 34 press against this Wall so that the heavy counterweight 61 will then be securely locked in a fixed position and therefore cannot damage the drawing apparatus during shipment. Screws 8 and the projections 34 then also serve as spacing means for preventing the rollers 76 of the counterweight from engaging with the opposite walls of guide rail 9. When the drawing apparatus arrives at its destination and is to be used for making drawings, it is only necessary to screw the screws 8 so far into the bores that the screw heads 10 engage upon the bottoms 26 of the recesses 26.

Although our invention has been illustrated and described with reference to the preferred embodiment thereof, we wish to have it understood that it is in no way limited to the details of such embodiment but is capable of numerous modifications within the scope of the appended claims.

We claim:

1. A carriage-type drawing apparatus, comprising a guide rail adapted to be connected to a drawing board so as to extend parallel thereto, a carriage movable along and guided by said guide =rail, a drawing head, a connecting bracket connected at one end to said drawing head and pivotably connected at its other end to said carriage and adapted to be pivoted from a first lower position in which said drawing head substantially engages with said drawing board to a second higher position in which said drawing head is spaced from said drawing board, locking means associated with said bracket and adapted in said first position of said bracket to be in locking engagement with said guide rail for thereby locking said carriage in a fixed position at any point along said guide rail to which said carriage has been moved, said locking means being released from said guide rail when said bracket is pivoted to said second position so as to permit said carriage then to be moved along said guide rail, said locking means is movably mounted on said carriage, said apparatus further comprising resilient means acting upon said locking means and tending to move the same to a released position from said guide rail, and actuating means for said locking means connected to and movable with said bracket for acting upon said locking means against the action of said resilient means when said bracket is in said first position and being disengaged from said locking means when said bracket is in said second position.

2. A drawing apparatus as defined in claim 1, wherein said actuating means comprise a control lever pivotably mounted on said bracket, and a transmitting member connected to said control lever and adapted in said first position of said bracket to be moved by said lever from a released position out of engagement with said locking means to at least one operative position in engagement with said locking means to press the latter against said guide rail.

3. A drawing apparatus .as defined in claim 2, wherein said transmitting member consists of a cam plate integral with said control lever.

4. A drawing apparatus as defined in claim 2, further comprising spring means acting upon said lever and tending to move the same together with said transmitting member to the release position of said member.

5. A drawing apparatus as defined in claim 4, wherein said transmit-ting member is adapted to be moved by said control lever to two different operative positions, said transmitting member in a first of said operative positions remaining by self-locking action in said position as long as the operator of said apparatus does not pivot said lever to the releasing position of said member, said transmitting member remaining in the second operative position only as long as the operator holds said lever in said position and being returned by said spring means to its released position when the operator takes his hand olf said lever.

6. A drawing apparatus as defined in claim 1, wherein said locking means comprise a brake shoe pivotably mounted on said carriage and having a brake surface at one side thereof adapted to engage upon said guide rail, said actuating means being adapted in said first position of said bracket to press against the other side of said brake shoe.

7. A carriage-type drawing apparatus comprising a guide rail adapted to be connected to a drawing board so as to extend parallel thereto between two opposite substantially horizontal sides thereof, said guide rail having a hollow part and rail tracks secured to the outside of said hollow part, a carriage movable along and guided by said rail tracks, a counterweight for said carriage within and movable along said hollow part when said carriage is moved, means for connecting said counterweight to said carriage for their common movement, and means for locking said counterweight in a fixed position in said hollow part so as to prevent it from moving during shipment of the apparatus, said locking means comprising at least one locking screw in a tapped bore in said counterweight, said guide rail having at least one aperture therein through which a screwdriver may be inserted for turning said locking screw so as to press said counter-weight against an inner wall of said hollow part.

8. A drawing apparatus as defined in claim 7, wherein said counterweight is provided with rollers adapted to roll along a first inner wall of said hollow part containing said aperture when said locking screw is screwed tightly into said tapped bore, said locking screw having a head tapered toward said first wall so that, when said screw is screwed outwardly of said tapped bore in said counterweight, said tapered head will engage into and press against the wall of said aperture and thereby press said counterweight against the opposite second wall of said hollow part and disengage said rollers from said first wall.

9. A drawing apparatus as defined in claim 8, wherein one side of said counterweight facing said second wall of said hollow part is provided with means projecting be yond the peripheral surface of said rollers and pressing against said second wall when the head of said locking screw engages upon the wall of said aperture in said first wall so that said rollers are then spaced from said first and second walls of said hollow part.

10. A carriage-type drawing apparatus comprising a guide rail adapted to be connected to a drawing board so as to extend parallel thereto between two opposite substantially horizontal sides thereof, said guide rail having a hollow part and rail tracks secured to the outside of said hollow part, a carriage movable along and guided by said rail tracks, a counterweight for said carriage within and movable along said hollow part when said carriage is moved, means for connecting said counterweight to said carriage for their common movement, said counterweight having a pair of transverse recesses in one side thereof near its opposite ends, an axle loosely in serted into each of said recesses, a pair of rollers rotatably mounted on the opposite ends of each of said axles, and resilient means in said recesses interposed between each of said axles and the walls of said recesses for holding said axles within said recesses.

11. A drawing apparatus as defined in claim 10, wherein said resilient means comprise at least one tubular member of a rubberlike material fitted on said axle and pressed with said axle into said recess.

12. A drawing apparatus as defined in claim 10, further comprising guide pulleys on the opposite ends of said guide rail, and at least one cablelike member extending over said guide pulleys and connected at its opposite ends to said axles and at a part intermediate said ends to said carriage, said cablelike member having a resilient tension due to said resilient means on said axles.

13. A drawing apparatus as defined in claim 10, wherein said counterweight is provided with a cutout near each end thereof and substantially centrally of each of said recesses, each of said axles having a flange which has a width substantially equal to the width of said cutout so as to prevent said axle from shifting in its axial direction, said resilient means comprising at least two rings of a rubber-like material on each of said axles at both sides of said flange.

14. A drawing apparatus as defined in claim 13, wherein said flange has at least one slot therein extending at right angles to the axis of said axle, and further comprising guide pulleys on the opposite ends of said guide rail, and at least one cablelike member extending over said guide pulleys and its opposite ends being inserted into said slots in said axles and secured to said flange, and a part of said member inserted into said socket bores so as to secure said cablelike member intermediate its ends being secured to member to said flanges. said carriage.

15. A drawing apparatus as defined in claim 14, wherein References Cit d said slot extends from the eri heral surface of said flange substantially to a diametric al line of said flange, said flange 6 FOREIGN PATENTS further having a Socket bore in the opposite side to said 1,347,619 2/1963 France.

slot, the bottom of said socket bore being connected to said slot, and thickened end portions on said cablelike HARRY N,HAROIAN,P i/7mry Examiner.

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