US 3605976 A
Description (OCR text may contain errors)
Sept. 20, 1971 ANGLE 3,605,976
PROGRAMMED CHARACTER PRINTING MEANS FOR STAMPING TUBING MATERIAL Filed March 17, 1970 INVENTOR United States Patent Oihce 3,605,976 Patented Sept. 20, 1971 US. Cl. 197-6 21 Claims ABSTRACT OF THE DISCLOSURE A heated stationary character bar cooperates with a program moved carriage having a solenoid actuated hammer, a printing tape supply reel and tubing supply reel carried by a cantilevered arm, a printing tape takeup reel driven by a solenoid actuated mechanism in response to movement of the hammer, and a cylindrical tubing receiving container. The carriage has a depending ball bearing nut guidingly received within an upwardly opening channel on the stationary base. A reversible electric motor selectively drives a lead screw within the channel that is threaded through the nut to selectively align the hammer with a desired character on the bar for thermal embedding a portion of the printing tape corresponding to the character into the tubing, which is preferably plastic.
BACKGROUND OF THE INVENTION These are numerous programmed selective character printing machines in the prior art, but their large number of parts and complicated structure render them quite expensive and susceptible to breakdown when employed on a production line basis. These machines are not satisfactorily adaptable to industrial usage in a factory assembly line, for example for the printing of coded information on plastic tubing, known in the art as spaghetti. After printing, this plastic tubing is cut into incremental lengths and respectively assembled with individual wires for the purpose of identifying the wires in the production of electronic equipment. A considerable volume of this tubing is used in a typical manufacturing facility and known machines have proved to be unreliable under these circumstances.
SUMMAJRY OF THE INVENTION It is an object of the present invention to provide apparatus for the above environment, which will be reliable, simple, inexpensive and thoroughly suited for the specific purpose.
With the present apparatus, a stationary base is provided with a heated character bar, an upwardly opening channel, and a reversible electric motor for selective program driving of a feed screw located in the channel. A moveable carriage slidingly rests upon the stationary base and has a depending nut guidingly received in the channel for threading engagement with the lead screw shaft.
A spool of thermal responsive tape is mounted on the outer end of an arm cantilevered to the carriage, which arm inwardly carries a spool of tubing to be printed upon. A solenoid ratchet mechanism drives a knurled take-up reel for the printing tape and feed mechanism for the plastic tubing, so that the tubing and tape are operatively guided past a solenoid actuated hammer. Retraction of the hammer away from the bar will actuate a switch, which will in turn actuate the ratchet mechanism to advance the printing tape and tubing one increment substantially corresponding to the spacing between characters.
The ratchet drive mechanism is particularly rugged in that it employs only one pivotally mounted locking pawl, a drive pawl pivotally mounted on the end of the corresponding solenoid armature, and a tension spring between the pawls for urging the pawls into operative engagement with a plurality of peripheral teeth on the pickup reel. Thus one take-up reel serves to feed both the tubing material and the printing tape.
BRIEF DESCRIPTION OF THE DRAWING Further objects, features and advantages of the present invention will become more clear from the following detailed description of the drawing, wherein:
FIG. 1 is a top plan view of the apparatus according to the present invention;
FIG. 2 is a cross-sectional view taken along line 22 of FIG. 1;
FIG. 3 is a cross-sectional view of only the movable carriage, taken along line 3-3 of FIG. 1;
FIG. 4 is a front elevation view of the apparatus according to FIG. 1;
FIG. 5 is a front elevation view of the character bar; and
FIG. 6 is an enlarged top plan view of only the movable carriage and character bar.
DETAILED DESCRIPTION OF THE DRAWING As shown in FIG. 1, a stationary base 1 rigidly mounts a reversible DC. motor 2, which through the interposition of a flexible coupling 3 drives a lead screw or threaded shaft 4. Suitable bearings 5 are provided on each end of the base 1 for rotatably mounting the opposite ends of the threaded shaft 4. A nut 6 threadingly receives the threaded shaft 4, and is rigidly carried by a second base or carriage 7. In this manner, rotation of the threaded shaft 4 in one direction by the reversible motor 2 will correspondingly produce a translation of the carriage 7 in a corresponding direction due to the threaded interengagement of the nut 6 and shaft 4.
The material to be printed upon is preferably a flexible walled plastic tubing, that is supplied wound on a reel 8. The tubing is drawn from the reel 8 by means of a tubing drive capstan 9 or takeup reel. The take-up reel 9 is advanced by means of a tubing drive ratchet solenoid 10 and held in its advanced position by means of a holding one-way pawl 11, which is spring biased by means of a ratchet tension spring 12, as will be described in more detail hereinafter.
From the take-up reel 9, the tubing passes into a cylindrical tubing receiver container 13 where it is held in storage until needed.
For printing characters, the carriage also carries an imprint solenoid 14 for driving a hammer, with retraction of the hammer actuating a limit switch 15, which will in turn energize the ratchet solenoid 10. Suitable guides 16 are arranged to guide the tubing in front of the imprint solenoid 14 as the tubing is being fed by the take-up reel 9. A standard supply of thermal responsive printing tape is carried by the tape supply spool 17, to be fed by the take-up reel 9 along the opposite side of the tubing from the imprint solenoid 14.
Suitable programmed controls, which may be of the type used in United States Patent No. 3,331,317, whose disclosure is incorporated herein, will control the relative movement between the carriage 7 and base 1. To accurately determine the relative position between the carriage 7 and base 1, the carriage 7 is provided with 2. depending pin type locator 18 and the base 1 is provided with an upwardly opening locator base channel 19 receiving therein the pin type locator 18. The locator 18 3 and channel 19 have cooperating Vernier scales for visual reference.
Rigidly mounted on the base 1 in opposition to the imprint solenoid 14, there is a character bar 20, which, as shown in FIG. 5, has a plurality of printing characters on its front face. A thermocouple 21 is used to determine the temperature of the character bar, so that the temperature may be adjusted by means of the heating element 22, which includes a resistive coil extending within and along the entire length of the bar 20, so that the temperature of the bar may be maintained at the proper degree for thermally embedding portions of the printing tape into the tubing with each blow of the hammer upon a selected character.
Accurate guiding during the relative rectilinear movement between the base 1 and the carriage 7 is obtained by means of an upwardly opening channel 23 extending for substantially the full length of the stationary base 1, which channel 23 receives therein the ball bearing guided nut 6. A planar way 24 extends on each side of the channel 23, with the two ways being in a common horizontal plane as seen in FIG. 2. The carriage 7 correspondingly has two planar ways 25 on each side of the nut 6, for sliding bearing support with the ways 24. Each of the bearings substantially closes a respective end of the channel 23, with the uppermost portion of each bearing 5 being substantially flush with the common plane of the ways 24, 25.
The inertia of the moveable carriage 7 is held to a minimum by means of the rigidly cantilevered arm 26, which extends away from the imprint solenoid 14 and towards the character bar at an acute angle with respect to the rectilinear movement between the bases 1 and 7. The tape supply spool 17 is held at the terminal end of the arm 26 and the tubing supply spool 8 is carried between the spool 17 and the imprint solenoid 14.
For striking the character bar 20, a hammer 27 is provided as the magnetizable armature of the imprint solenoid 14. The solenoid 14 includes the conventional type of internal spring mechanism (not shown), which will bias the hammer 27 away from the character bar 20, with solenoid energization driving the hammer 27 into engagement with the character bar 20, with the tubing material and printing tape interposed. After the character bar 20 has been struck by the hammer 27, the abovementioned spring mechanism will withdraw the hammer 27 to its rearward position where it will actuate the switch 15.
To feed additional printing tape and the tubing material, actuation of the switch 15 will energize the tubing drive ratchet solenoid 10, which will move its armature 28 toward the character bar 20. At one end of the armature 28, there is pivotally mounted a one-way pawl 29, which may pivot into and out of engagement with a plurality of ratchet teeth 30 rigidly secured around the periphery of the tubing drive capstan 9'. It is thus seen that when the solenoid 10 is energized to move the armature 28 toward the character bar 20, the pawl 29 will correspondingly cause the reel 9 to rotate in the clockwise direction, as shown in FIG. 6, which will advance the tubing and printing tape an increment substantially equal to the arcuate distance between adjacent teeth 31 When the solenoid 14 is again energized by the program to move its armature 27 toward the character bar 20, the switch 15 will be deactuated to deenergize the solenoid 10, so that the internal spring mechanism (not shown) of the solenoid 10 will retract its armature 28 away from the character bar 20. Upon retraction of the armature 28, the pawl 29 will pivot away from the reel 9 and ratchet counterclockwise over the adjacent tooth 30, in the known manner of a one-way pawl. During this ratchetting, the one-way pawl 11 will hold the reel 9 in its position. Positive feeding of the printing tape 31 and tubing 32 is obtained by means of scoring or knurling 33 on the tube engaging periphery of the reel 9, particularly with the cooperation of the adjacent arcuate portion of the guide 16 that will cause the normally circular crosssectioned resilient tubing 32 to be pressed tightly down against the knurling 33 in assuming the shape shown in FIG. 3. The tape 31 will be carried along by the tubing 32 as it passes between the tubing 32 and the adjacent guide structure 16 directly radially outward of the tubing 31 on the reel 9 or the tape 31 may be axially diverted separately and collected on the reel 9.
Proper feeding of the tape 31 and tube 32 is obtained through a cooperation of the abovementioned reel structure and a suitable tension placed upon the spools 8 and 17. Shafts 34 and 35 are rigidly connected at one end to the arm 26, as shown in FIG. 6. The opposite end of each of the shafts 34, 35 is threaded to receive a tension adjusting wing nut 36, 37, respectively. It is thus seen that through tightening or loosening the wing nuts 36, 37, the tension upon the tubing 32 and tape 31, respectively, may be correspondingly increased or decreased.
After the printing has been placed upon the tubing and it has passed arcuately around the pick-up reel 9, the printed tubing will pass through a receiving slot 38 in the cylindrical tubing receiver 13. In the case where the tape 31 is radially outward of the tubing 32 when they pass around the reel 9, the spent tape will also pass into the receiver 13. However, as mentioned above, if the tape 31 is axially displaced with respect to the tubing 32 by the guides 16 on the periphery of the reel 9, the tape 31 may be separately taken up by the reel 9 or otherwise discarded separately from the receiver 13.
While a preferred embodiment has been specifically described and shown in the drawing, with various modifications mentioned, it is contemplated that according to the broader aspects of the present invention there may be further variations, modifications and embodiments.
OPERATION The present printing apparatus will be used with a numerical positioning control or computer with a control tape fed into it, which will then send a signal to the printing apparatus drive motor. The motor will then be actuated to rotate the threaded shaft in the required direction to move the carriage relative to the base and obtain a proper alignment between the hammer and a selected character on the bar, as determined by the pin type locator and locator base channel that have electronic means (not specifically shown) for electrically feeding back the precise relative position between the base and carriage. When the carriage reaches the predetermined called for position, a signal will be sent by the program control to the imprint solenoid for driving the hammer against the tubing and tape backed up by the character bar in a rapid blow.
When the hammer is retracted and strikes the limit switch, a signal will be sent to the ratchet solenoid for movement of the pawls to rotate the reel and advance the tubing and printing tape. During this process, the guides will assure a proper alignment between the hammer, tubing, printing tape and character bar. During ratchetting of the take-up reel, the carriage will be moved by the program control into the position of the next character to be printed.
The present apparatus is an improvement over the prior devices for printing characters on tubing for the purpose of numbering wires using numerical positioning control type equipment. It has less moving parts, thereby causing less maintenance problems.
What is claimed:
1. Apparatus for printing characters on an indefinite length material fed from a roll supply, according to a predetermined program, comprising:
a first base;
a second base mounted for rectilinear movement relative to said first base between two terminal positions; first power means for rectilinearly moving said first and second bases relative to each other selectively to a plurality of predetermined relative positions between said two terminal positions as determined by the predetermined program;
a bar rigidly mounted on said first base and having a plurality of raised printing characters serially ar ranged parallel to the rectilinear movement between said two bases;
a hammer carried by said second base and mounted for movement toward and away from said bar;
second power means for driving said hammer against a selected one of said raised printing characters in each of said plurality of predetermined relative positions, as determined by the predetermined program;
tape means carried by said second base for supplying printing tape and for feeding the printing tape between said hammer and said bar in increments correlated to the driving of said hammer against said bar; and material means carried by said second base for supplying the material and for feeding the material between said hammer and said bar in increments correlated to the driving of said hammer against said bar and in operative relationship with the printing tape for character printing with each hammer driving.
2. The apparatus of claim 1, including means for heating said bar to deposit with thermal bonding a portion of the printing tape with each driving of the hammer.
3. The apparatus of claim 1, wherein said first base is stationarily mounted.
4. The apparatus of claim 1, wherein said first power means includes a threaded nut rigidly carried by one of said bases, a threaded shaft rotatably mounted on the other of said bases and threaded through said nut, and a reversible motor drivingly connected to said threaded shaft.
5. The apparatus of claim 4, wherein said reversible motor is rigidly mounted on said first base, and including bearings mounted on said first base respectively rotatably carrying;each terminal end of said threaded shaft.
6. The apparatus of claim 4, wherein said first base has an upwardly opening channel slidingly receiving therein said nut to form guide means for the relative movement between said bases.
7. The apparatus of claim 6, wherein said reversible motor is rigidly mounted on said first base, and including bearings mounted on said first base respectively rotatably carrying each terminal end of said threaded shaft; said bearings effectively closing the opposite ends of said channel; said first base having a planar Way on each side of and extending for the entire length of said channel, and each planar way lying in a plane substantially flush with the uppermost portion of each bearing; said second base having a planar way on each side of said nut and being in sliding engagement with a corresponding one of said first base planar ways.
8. The apparatus of claim 1, including means for determining the relative position of said bases, including a locator channel carried by one of said bases to extend in the direction of relative movement between the bases, and a locator pin received in said locator channel and carried by the other of said bases.
9. The apparatus of claim 8, wherein said locator channel and said locator pin have cooperating Vernier scales for a visual determination of the relative position between the bases.
10. The apparatus of claim 1, wherein said hammer is mounted on said second base for rectilinear movement toward and away from said bar, said second power means including a solenoid drivingly connected to said hammer.
11. The apparatus of claim 10, wherein said solenoid includes a selectively electrically energized magnetic coil and said hammer extending through said coil to constitute an armature; and said hammer being magnetizable.
'12. The apparatus of claim 1 wherein said tape means includes a shaft extending perpendicular to the rectilinear movement and rigidly secured at one end to said second base, said shaft having a thread and nut on its other end for securing a spool of printing tape on the shaft with an unwinding tension adjusted by means of said nut.
13. The apparatus of claim 1, wherein said tape means includes a take-up reel for the printing tape, a shaft rotatably mounting said reel about an axis perpendicular to the path of rectilinear movement, ratchet teeth peripherally arranged with respect to and drivingly carried by said reel, a one-way locking pawl pivotally mounted on said second base for movement into and out of engagement with said ratchet teeth, a solenoid having a reciprocating armature, a one-way pawl pivotally mounted on one end of said armature for pivotal movement into and out of engagement with said ratchet teeth, and a tension spring mounted between said pawls for biasing each of said pawls into engagement with said ratchet teeth.
14. The apparatus of claim 13, including guide means for holding the material against said reel to constitute said reel feed means for the material.
15. The apparatus of claim 13, including switch means mounted on said second base for actuation by movement by said hammer away from said bar to control the energization of said solenoid.
16. The apparatus of claim 1, said tape means including solenoid means energizable to advance the printing tape one increment; and switch means actuated by movement of said hammer away from said bar to energize said solenoid means.
17. The apparatus of claim 1, wherein said material means includes a shaft extending perpendicular to the rectilinear movement and rigidly secured at one end to said second base, said shaft having a thread and nut on its other end for securing a spool supply of material on the said nut.
18. The apparatus of claim 17, wherein said first base is stationarily mounted and said second base includes a shaft with an unwinding tension adjusted by means of rigid cantilevered arm extending toward said bar and away from said hammer at an acute angle with respect to the rectilinear movement; said arm carrying said shaft; said tape means including a tape shaft extending perpendicular to the rectilinear movement and having one end rigidly carried by said arm between said material shaft and the terminal end of said arm, said tape shaft having a thread and nut on its other end for securing a spool of printing tape on said tape shaft with an unwinding tension adjusted by means of said nut.
19. The apparatus of claim 1, including a cylindrical container having an axis perpendicular to the rectilinear movement and being rigidly carried by said second base; said container having an opening on its periphery for receiving the printed material.
20. The apparatus of claim 1, said tape means includ ing solenoid means energizable to advance the printing tape one increment; and switch means actuated by movement of said hammer away from said bar to energize said solenoid means; said material means including a material shaft extending perpendicular to the rectilinear movement and rigidly carried by said arm between said hammer and said tape shaft.
21. The apparatus of claim 1, including a single driven reel feed for both the tape and material.
References Cited UNITED STATES PATENTS 1,823,110 9/1931 Luedtke et al. 10l-21 2,596,721 5/1952 Pentecost et al. 10118 3,408,930 11/1968 Chammess et a1. 10l93C 3,429,414 2/1969 Bradbury 10193C WILLIAM B. PENN, Primary Examiner US. (:1. X.R.