US 3319666 A
Description (OCR text may contain errors)
May 16, 1967 Filed July 22, 1964 O. V. LANGFORD ETAL PACKAGE BANDING TOOLS Sheets-Sheet 1 y 1967 o. v! LANGFORD ETAL 3,319,666
PACKAGE BANDING TOOLS Filed July 22, 1964 I5 Sheets-Sheet 2 y 1957 o. v. LANG-FORD ETAL 3,319,666
PACKAGE BANDING TOOLS Filed July 22, 1964 3 Sheets-Sheet 5 PM W;
(7M n W United States Patent Ofl ice 3,319,666 PACKAGE BANDING TOOLS Oswald Victor Langfor-d and Robert David Sansum, London, England, assignors to Seal-Less Strapping Limited, London, England, a corporation of Great Britain 1 Filed July 22, 1964, Ser. No. 384,471 Claims priority, application Great Britain, Aug. 14, 1963, 32,081/ 63 8 Claims. (Cl. 140-932) This invention relates to tools for binding packages and, in particular, to such a tool of the type essentially comprising means for tensioning a loop of flexible material around the package, and a jointing unit for then interconnecting the overlapping portions of said material.
A tool with these essential features is set forth for example in Patent No. 3,035,814, with a suitable motor for powering the tensioning means, and it is an object of the present invention to power such a tool more extensively.
The present invention therefore enables the power output of the tool motor to be directed alternatively either to the tensioning means or to the jointing unit, under manual control of the operator. A tool in accordance with the invention comprises a motor which provides a reversible drive transmitted through oppositely-acting freewheeling clutches to the tensioning means and the jointing unit and a control for causing operation of said drive alternatively in either direction and thereby actuating said tensioning means or said jointing unit without the other, through its respective clutch. For this purpose the motor may be of any suitable reversibly rotatable type and the control need be merely for starting and stopping said motor in either direction.
The motor, when driving the tensioning means, may be self-stopping in face of the resistance offered by the full tension required, and said means 'is preferably capable of holding any applied tension independently of said motor. A motor which is pneumatic and capable of remaining in operation until it stalls when this tension is attained, simply by keeping it in connection with its source of com ressed air, can conveniently be used for this purpose, and may be of the vane and rotor or fin turbine types.
The jointing unit preferably includes means for severing the flexible material from the part thereof on which the tensioning means is operative and the actuation of said unitmay be such that an operating cycle thereof merely has to be initiated and then left to finish automatically.
It the motor is pneumatic and reversible, its operation can be effected in an especially simple and convenient manner by means of a single valve controlling the air supply to this motor in its respective directions of rota-' tion. Thus, such a control valve needs merely to be held open in one sense to cause such rotation in the direction, and for as long as required, for tensioning, preferably as shown by the consequent stalling of the motor, and then to be'opened in another sense to cause rotation in the reverse direction, for jointing. Said valve is preferably adapted to be opened in such a way as merely to initiate the rotation required for jointing, followed immediately by release of said valve so that it closes, for which purpose it may be associated with a by-pass controlled by an auxili-ary valve which is automatically opened by the jointing unit at the beginning and closed thereby at the end of its operating cycle.
A- typical pneumatically operated tool in accordance with the invention will next be described in fuller detail by way of example, as shown in the accompanying drawings whereof:
3,319,666 Patented May 16, 1967 FIGURE 1 is a sectional elevation from the front i.e. looking at the face of the tool into which the strip is loaded as shown, omitting the front cover plate, the control valve and the manual lever of the anchoring gripper;
FIGURE 2 is a rear elevation of the tool with the control valve lever positioned for tensioning and showing some parts omitted or broken away;
FIGURE 3 is a similar rear elevation with the control valve lever positioned for actuation of the jointing device and with parts omitted or broken away differently;
FIGURES 3A and 3B are end elevations in the direction of the arrows 3A and 3B of FIGURE 3 respectively; and
FIGURES 4A to 4C are similar sections of the control valve in its three operating positions, viz. those respectively for tensioning, for initiating the operation of the jointing unit with the auxiliary by-pass valve opened, and in neutral after this auxiliary valve has closed automatically to terminate the jointing operation.
In this embodiment the tool is adapted for operating with metal strip as the flexible material and its arrangement is generally similar to that according to our prior Patent No. 3,035,814 already mentioned.
However instead of the dies of the jointing unit for sealing and severing the strip being actuated in the required sequence by means of a pair of oppositely swinging manual levers, they are here operated from a single drive shaft 10, which shaft may, as shown, conveniently be that of the eccentric 11 for lowering the first die 12 to be operated, and geared to the shaft 13 of the eccentric 14 of the second die 15 carrying the severing blade 16 on its tensioning side. The unit is thus adapted for unidirecional rotatable actuation for the purpose of the present invention, through a fin al gear 17 of a drive from the motor 18, which gear can again conveniently :be on the same shaft 10.
The tensioning means of Patent No. 3,035,814 is here also adapted for similar actuation by replacement of its reciprocable gripper by a unidirectionally rotatable serrated wheel 19 capable of being manually raised from an associated anvil 21? on the base 21 of the tool for insertion of the strip part S1 to be tensioned and also, if necessary, for its subsequent removal. The tensioning means is in other respects essentially unaltered and as before includes a gripper 22 for holding the applied tension between said wheel and the jointing unit, which holding gripper is here sufiiciently released to permit the aforementioned removal of the strip by the sudden relaxation of tension in the latter when it is severed. The required raising and lowering of the tensioning wheel 19 can be effected by mounting it together with an associated final gear 23 on an upwardly swinging arm 24, the pivot 25 of which arm (see FIG. 1) is coaxial with or, as shown, sufliciently near the axis of the next gear 26 (see FIG. 2), through which the drive from the motor is transmitted, to ensure that these gears always remain wholly or sufiiciently in mesh. Said arm can thus be swung upwardly by an appropriate manual lever 27 against a spring 28 strong enough to urge said wheel into operative engagement with the strip.
The unidirectional motor of Patent No. 3,035,814 is here replaced by a reversible one whose output is connected through a driving gear train to the aforementioned final gears 17 and 23' of the jointing unit and the tensioning wheel respectively, which train can conveniently be common to both, up to the aforementioned gear 26. For the purpose of ensuring that the rotation of the motor is then transmitted only to the jointing unit in one direction and only to the tensioning wheel in the other direction, each of said final gears includes an appropriately acting free-wheeling clutch 17a and 23a which can con veniently be of ratchet type.
The required control of the motor for causing rotation thereof in opposite directions consists of a valve generally denoted by reference 29 which can conveniently be mounted on the side of the motor above the aforementioned drive shaft of the jointing unit. This valve may consist of a rotatable core 30 fitted with a manual lever 31 and capable of taking up any of three positions. In the first of these positions (see FIGS. 2 and 4A) the valve connects one port 32 to the motor with a supply of compressed air through inlet 33 and another port 34 with exhaust 35: and in the second position (see FIGS. 3 and 4B) connects said other port 34 to said air supply inlet and said first port 32 with said exhaust; both ports being closed in the third intermediate neutral position (see FIG. 40). It should be noted that the actual connecting pipes between these ports and the motor are omitted from the drawings.
The actuation of the valve 29 between this neutral position and its first position, i.e. that for causing rotation of the motor in the direction to turn the tensioning wheel 19, is preferably fully positive so as to permit feeling by the operator of the stalling of the rnotor consequent on completion of tensioning, the limit of which can be set by an adjustable relief valve 36 in the passage from the rotatable core 30 to the first port 32.
The valve-29" is however preferably biassed by suitable spring means 37 from its second position, i.e. that for causing rotation of the motor in the direction to actuate the jointing device, back into said neutral position, to permit mere momentary opening of the valve in this sense, followed by release thereof for return to neutral, thereby enabling said actuation of the jointing device to be just initiated by the operator and then to be completed automatically. An auxiliary spring-loaded valve 38 for this purpose controls a by-pass passage 39 in the valve casing, between the air supply inlet 33 and the port 34, and is actuated by a cam 40', against preferably on the aforementioned drive shaft 10 of the jointing unit, so as to open said bypass passage when said unit starts to operate (see FIG. 4B) and to remain open under the influence of said cam until the latter permits it to close and thereby terminate the operating cycle of the unit.
The free end S2 of the strip is anchored, as in accordance with Patent No. 3,035,814, by means of a holding gripper 41 on the base 21 of the tool, on the same side of the jointing unit as the tensioning means, which gripper is closed by means of a manual lever 42 but may be thrown open automatically by means of another cam 43 on the drive shaft 10, which thrusts on said lever through a plunger 44 during the final part of the operation of said unit.
1. A tool for binding packages, of the type set forth, comprising a reversible rotating power-driven element, tensioning means, jointing means, a pair of oppositely-acting free-wheeling clutches, one of which operatively connects said tensioning means to said power-driven element and the other of which operatively connects said jointing means to said power-driven element, and control means for causing rotation of said power-driven element alternatively and selectively in either direction, whereby said tensioning means will be actuated independently of said ment and reversible to effect reversing of said element.
3. A tool in accordance with claim 2 wherein said motor is self-stopping in face of the resistance oiferedby the full tension required and said tensioning means is adapted to hold an applied tension independently of said motor.
4. A tool in accordance with claim 2 wherein said motor is pneumatic and said control means includes a single valve controlling the air supply to said motor in jointing means when said control means causes said powerdriven element to rotate in one direction, and said jointing means will be actuated independently of said tensioning means when said control means causes said power driven element to rotate in the opposite direction.
2. A tool in accordance with claim 1 and including a motor operatively connected to said power-driven eleits respective directions of operation, whereby said control valve may be operated in one position to cause said motor to operate in one direction for tensioning, and said control valve may be operated in another position to cause the motor to operate in the reverse direction for jointing.
5. A tool in accordance with claim 2, wherein the motor is pneumatic and capable of remaining in operation until it stalls when the required tension is attained, by keeping it in connection with its source of compressed air.
6. In a tool for binding packages of the type set forth, said tool having tensioning means and jointing means, an improvement comprising a reversible pneumatic motor, a pair of oppositely-acting free-wheeling clutches driven by said motor and operatively connecting said motor to the tensioning means and the jointing means, respectively, a single control valve controlling the air supply to said motor in its respectivedirections of operation, means urging said control valve toward a closed position, said control valve being adapted to be opened to initiate an operating cycle of said jointing means, and means associated with said valve for permitting said operating cycle to proceed to completion automatically after it has been initiated.
7. A tool in accordance with claim 6 wherein the means associated with said control valve comprises a bypass air conduit to said motor, an auxiliary valve in said conduit, and means associated with said jointing means for opening said auxiliary valve at the beginning of the operating cycle and for closing said auxiliary valve at the end of the operating cycle.
8. In a tool for binding packages of the type set forth, said tool having tensioning means and jointing means, an improvement comprising a reversible pneumatic motor, a pair of oppositely-acting free-wheeling clutches driven by said motor and operatively connecting said motor to the tensioning means and the jointing means, respectively, a single control valve controlling the air supply to said motor in its respective directions of operation, whereby said control valve may be operated in one position to cause said motor to operate in one direction for tensioning, and said control valve may be operated in another position to cause the initial operation of said motor in the reverse direction for jointing, and means responsive to the operation of the jointing means for continuing the air supply to said motor until the jointing cycle has been completed.
References Cited by the Examiner UNITED STATES PATENTS 1,900,238 3/ 1933 Harvey .--93.2 2,257,090 9/1941 Childress 81-9.1 2,933,958 4/1960 Kochler et al. 819.1 3,035,814 5/1962 Mosey et al. 254-511 3,198,218 8/1965 Ericson et al. 819.1 X 3,232,217 2/1966 Harmon et al. 81-9.1 X
WILLIAM J. STEPHENSON, Primary Examiner.