US3673877A

US3673877A - Power or manual drive cable traction apparatus

Info

Publication number: US3673877A
Application number: US99462A
Authority: US
Inventors: Charles Jean Pierre Lebre
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-12-26
Filing date: 1970-12-18
Publication date: 1972-07-04
Anticipated expiration: 1989-07-04
Also published as: GB1270906A; BE760670A; JPS4941779B1; CH521921A; NL7018793A; BG17742A3; AT312866B; DE2061710A1

Abstract

In a cable-pulling device of the type comprising clamps pulling alternately and continuously a cable or rope by means of a mechanism having a driving shaft projecting from the case of the apparatus and provided with a manual control lever, an engine is fitted to the apparatus case and adapted to drive said control lever through a chain carrying a crankpin pivotally connected to an arm releasably coupled to said control lever.

Description

United States Patent Lebre July 4, 1972 1 POWER OR MANUAL DRIVE CABLE References Cited TRACTION APPARATUS UNITED STATES PATENTS [72] inventor: Charles Jean Pierre Lebre, 16 bis bou- 3,237,920 3/1966 Dohmeiel' 5 levard Fleury 91, Viry-Chatillon, France 3,307,415 3/1967 DObbS ..74/37 3,572,635 3/1971 Desplats ..254/l06 221 Filed: Dec. 18,1970 2 99 4 2 Primary Examiner-Robert C. Riordon Assistant Examiner-David R. Melton AttarneyLinton & Linton [30] Foreign Application Priority Data Dec. 26, 1969 France ..6945047 [571 ABSTRACT Jan. l, 1970 France ..7002397 [n a cab|e pu]]ing device of the type comprising clamps pulling alternately and continuously a cable or rope by means of a [52] US. Cl ..74/37, 254/105 mechanism having a driving Shaft projecting from the case of [51] P Cl "Gmm3/02B66f1/00 the apparatus and provided with a manual control lever, an [58] F raid of Search ..254/105-10",7,t/53l engine is fitted to the apparatus case and adapted to drive Said control lever through a chain carrying a crankpin pivotally connected to an arm releasably coupled to said control lever.

12 Claims, 3 Drawing Figures PATENTEBJHL 47972 3.673.877

CHARLES TEA/V PIERRE [um By M WM fl TTOR N EVS PATENTEDJUL "'4 m2 3, 673 877

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2 or 2 .unpnapn-aan INVENT'OR CHARLES TEAN PIERRE LEBRE ATTORNEYS POWER OR MANUAL DRIVE CABLE TRACTION APPARATUS BACKGROUND OF THE INVENTION Traction apparatus acting upon a cable or rope through the medium of a pair of clamps of which the opposed working and return movements are obtained by manually operating a reciprocating control lever are already known. These apparatus are advantageous notably in that they permit of pulling illimited cable lengths without exerting any flexion stress on the cable.

However, the manual actuation of the control lever is attended by serious inconveniences for the operator, especially in the case of heavy loads to be pulled on relatively great distances, due on the one hand to the low rate of feed and on the other hand to the fatigue caused to the operator.

It was therefore proposed to drive these apparatus by means of an engine or motor, notably gas or other engines, but this drive proved rather difficult to achieve due to the relative slowness of the motion to be imparted to the apparatus, to the magnitude of the load (which is constant from the beginning to the end of the stroke of the actuating lever) and to the impossibility of accumulating a force by inertia, for example by means of a flywheel. Moreover, the use of a crankshaft, as a conventional means for transforming a rotary motion into a reciprocating motion to be imparted to the control or drive lever of the apparatus, would give in this case but poor results due on the one hand to the considerable space required for the crankshaft movement and on the other hand to the continuous variation in the applied torque which entails a useless power consumption during one fraction of the stroke.

Other means could also be used for automatically actuating the reciprocating or oscillating control lever, such as hydraulic or pneumatic cylinders or actuators, but these means are rather cumbersome, scarcely convenient and require in addition to the apparatus proper generating sets or other power sources which are not only expensive but limit the autonomy of the apparatus.

SUMMARY OF THE INVENTION It is the essential object of the present invention to provide a traction apparatus of the type broadly set forth hereinabove, which comprises simple mechanical means designed for actuating its control lever from a gas engine or any other similar power source mounted on the case of the apparatus.

According to this invention, the mechanical means contemplatcdcomprise a sprocket of relatively small diameter, rotatably driven from the engine, preferably through a suitable reduction gearing, said sprocket being in constant driving engagement with a suitable transmission member having one point pivotally connected to an arm operatively connected in turn to the control lever of the apparatus, whereby the continuous meshing engagement between said sprocket and said transmission member causes the reciprocating movements of said pivoted arm and therefore of the lever operatively connected thereto. With this construction, the tractive effort is transmitted through a constant lever arm operating by thrust, the length of said lever arm corresponding to the half of the pitch diameter of said sprocket.

The transmission member associated through said pivoted arm with the control lever of the apparatus may advantageously consist of an endless roller chain passed over said sprocket driven from the engine and over another sprocket mounted for loose rotation in a bearing carried by the case of the apparatus, said chain carrying on its outer side a crankpin having mounted thereon for loose rotation one end of a connecting rod having its opposite end pivoted to said arm operatively connected in turn to the control lever. To facilitate the movement of said chain along an arcuate path, the chain may be guided along a circular are formed by guide members adjustably secured to the case of the apparatus.

According to a modified form of embodiment of this invention, the endless roller chain may be connected to the control lever through a two-section connecting-rod so mounted as to afford a limited relative sliding play between each other, one section of said connecting-rod being pivoted to the crankpin of said endless roller chain and the other section is coupled to the control lever of the apparatus.

In the drawings attached thereto:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic side elevational view of a cable traction apparatus according to this invention;

FIG. 2 is a fragmentary longitudinal section showing a sliding connecting-rod adapted to be fitted as an alternative to the apparatus of this invention, and

FIG. 3 is a vertical section taken along the line III-III of FIG. 2 and showing a detail on a larger scale.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The apparatus illustrated in side-elevational view in FIG. 1 is of the type adapted to pull a cable or rope and its internal mechanism is now well-known per se and therefore will not be described herein. This apparatus is enclosed in a case I and comprises a shaft emerging therefrom, to which is attached a control lever 2 adapted to be fitted with a telescopic extension (not shown) and, when oscillated in the directions shown by the arrows A and B, to cause a cable 3 to move through the apparatus. According to this invention, a complementary lever 5 is fitted to the manual lever 2 by means of a collar-forming device 6 secured to this lever 2 by means of a lock screw 7.

The complementary lever 5 comprises a strap-shaped portion 8 provided with a transverse pivot pin 10 to which one end of an arm 9 is pivoted, this arm 9 consisting for example of a section of square-sectioned tube having its opposite end pivoted through another pivot pin 23 to a connecting-rod 22 pivoted in turn to a crankpin 19 detachably mounted laterally to an endless roller chain 18 and constituting one of the assembling links of chain 18, by means of a pair of

pivot pins

20, 21. The endless chain 18 is passed over a pair of

chain sprockets

16, 17, the pinion 17 being mounted for loose rotation in a bearing carried by the lower portion of case I, pinion 16 being rigid on the one hand with a stub shaft engaged in a bearing secured to the upper portion of case 1 and on the other hand with a toothed wheel 15 of relatively great diameter, in constant meshing engagement with a driving pinion 14 of relatively small diameter, rotatably driven in turn from a gas engine 4 (or any other suitable internal-combustion engine) mounted to the upper portion of the apparatus case I.

The arm 9 is adapted to be easily connected to and disconnected from the strap 8 according as the apparatus is to be driven by the engine 4 or manually; to this end the arm 9 has slidably mounted thereon a notched sleeve 12 engageable by projections 11 formed on the strap 8, a set screw 13 being provided for locking the sleeve 12 in its power-drive position (shown in FIG. 1); releasing the screw 13 will permit of disengaging the arm 9 from strap 8.

The mode of operation of the device will be readily understood from the above description. When it is desired to actuate the apparatus automatically from the engine 4, the arm 9 is locked to the strap 8 as explained hereinabove and the engine 4 is started, its rotational speed being reduced through the step-down

gears

14, 15 and its torque transmitted through the driving sprocket 16, thus causing the chain 18 to move continuously around the

sprockets

16, 17; under these conditions, the crankpin 19 mounted to this chain will carry along and oscillate the arm 9 to actuate the lever 2. In order to obtain a part-circular movement of crankpin l9 and therefore of chain 18,

arcuate guide members

24, 25 slidably engaged by lever 2 and adapted to co-act with one end of a flat connecting-rod 32 having its other end provided with a sleeve-like member 33 having slidably mounted therein a link 34. This link 34 has its outer end mounted for free rotation for example by means of a needle bearing 35 on the aforesaid crankpin 19. The sliding mounting of link 34 in the sleeve-like member 33 of connecting-rod 32 is obtained by means of balls 36 engaging

longitudinal grooves

37 and 38 formed on the one hand in the upper and lower edges of link 34 and on the other hand in the corresponding inner faces of wedge-shaped members 39 interposed between said upper and lower faces of sleeve 33 and the corresponding faces of link 34. Spring means 40 disposed at the ends of each row of balls 36 are provided for mutually centering these balls so that they can move along the

grooves

37, 38 without abuting against the ends of these grooves, as this would produce a wedging effect on link 34. The wedge-members 39 disposed within the sleeve-like member 33 are locked in position after proper adjustment by means of set screws 41 co-acting with elongated apertures (not shown) formed in the connecting-rod 32, these wedgelike members 39 constituting convenient means for adjusting the free sliding movements of link 34, without any undue play.

To permit the easy connection or disconnection of connecting-rod 32 with respect to control lever 2, according as the apparatus is to be power-operated or manually operated, a control lever 42 is pivoted laterally on the strap-shaped member 31, the pivotal movement of lever 42 in one direction causing through eccentric means the meshing engagement of teeth 43 formed in said strap-shaped member with corresponding teeth l 44 carried by the connecting rod 32, in order rigidly to interconnect these

members

31 and 32. Actuating the lever 42 in the opposite direction will disengage the

teeth

43, 44 from one another to disconnect the strap 31 from rod 32.

, The operation is substantially the same as in the case of the apparatus described hereinabove with reference to FIG. 1, the movement of the end of link 34 which is associated with crankpin 19 along the closed-circuit path described by chain 18 causing the lever 2 to be reciprocated for pulling the cable. The pivotal connection between crankpin 19 and arm 9 by means of connecting-rod 22 of H6. 1 is advantageously replaced by the sliding mounting of connecting-rod 34. It will be noted that in the assembly illustrated in FIGS. 2 and 3 the use-of

guide plates

24, 25 is no more necessary due to the sliding mounting of connecting-rod 34. lt is clear that this sliding mounting of connecting-rod 34 may be obtained by using suitable means other than balls 36, for example anti-friction pads or shoes.

It will be readily understood by those conversant with the art that the above description is given by way of illustration, not of limitation, since many modifications and additions may be brought thereto without departing from the basic principles of the invention. Thus, more particularly, the engine 4 used for powering the apparatus may be of any other suitable type and be associated with a torque limiter 45 interposed in the shaft driving the sprocket 16, in order to impart a greater safety of operation thereto; on the other hand, this engine 4 may advantageously operate at suitably selected speed ranges or values. it will also be apparent that although in the specification the crankpin 19 is described as constituting a detachable link interconnecting adjacent links of the roller chain, this .crankpin could also be simply carried by an ordinary chain link without interconnecting other chain links.

Whatl claim is:

1. A traction apparatus operating by successive reciprocating movements, adapted to be controlled at will either manually or automatically through power means, which comprises a control lever adapted to be reciprocated and mounted on a shaft projecting from the case enclosing the cable-traction mechanism of the apparatus, wherein an engine is mounted to the case of the apparatus and adapted to drive in rotation a driving sprocket in continuous meshing engagement with a transmission member pivoted at one point to one end of a connecting arm having its other end coupled to the control lever of the apparatus, whereby the movement imparted to said transmission member as a consequence of its meshing engagement with said sprocket produces a reciprocating movement of said connecting arm and therefore of the control lever of the apparatus which is coupled thereto.

2. Apparatus as set forth in claim 1, wherein said transmission member consists of an endless roller chain passing over said driving sprocket and over a return sprocket mounted for loose rotation in a bearing carried by the case of the apparatus, said endless roller chain carrying on its outer side face a crankpin on which one end of a connecting-rod is mounted for free rotation, the other end of said connecting-rod being pivoted to said connecting ann coupled to said control lever of the apparatus.

3. Apparatus as set forth in claim 2, wherein said crankpin constitutes a detachable link for assembling said endless roller chain.

4. Apparatus as set forth in claim 2, wherein said connecting arm is secured to said control lever of the apparatus through a quick-release coupling device.

5. Apparatus as set forth in claim 4, wherein said quickrelease apparatus consists of a strap having a collar-shaped end disposed around said control lever, the end of the connecting arm being pivoted to a transverse pivot pin carried by said strap, and being further adapted to be locked thereto by the engagement of studs or like projections carried by said strap into notches formed in a sleeve member adapted to slide on said connecting arm and to be set in any desired and suitable position therealong by means of set screws.

6. Apparatus as set forth in claim 1, wherein said transmission member consists of an endless roller chain following a rectilinear or arcuate path between said driving sprocket and said return sprocket mounted for loose rotation in a bearing carried by the case of the apparatus, said chain carrying a crankpin on its outer side, said crankpin having mounted for free rotation thereon the end of a link slidably mounted in a hollow portion of a connecting-rod having its end coupled to the control lever of the apparatus, the sliding stroke of said link being determined by the arcuate or rectilinear movement of said chain.

7. Apparatus as set forth in claim 6, wherein the sliding movement of said link in the hollow portion of said connecting-rod is guided by balls engaging grooves formed in the upper and lower faces of said connecting-rod and in the corresponding faces of tapered wedging member fitted in the hollow portion of said connecting-rod.

8. Apparatus as set forth in claim 6, wherein the end of said hollow connecting-rod is connected to the control lever of the apparatus through a quick-release coupling device.

9. Apparatus as set forth in claim 8, wherein said quickrelease coupling device consists of a strap rigid with the control lever of the apparatus and adapted to co-act with the end of said hollow connecting-rod, said strap carrying an eccentric the operation of which causes the engagement of teeth carried by said strap with corresponding teeth carried by said hollow connecting-rod.

10. Apparatus as set forth in claim 2, wherein arcuate guide plates adapted to cause said endless chain to follow a substantially curvilinear path between said driving sprocket and said return sprocket, are adjustably secured to the case of the apparatus.

11. Apparatus as set forth in claim 1, wherein said driving sprocket is rigid with the hub of a relatively large toothed wheel, possibly incorporating a torque limiter between it and said sprocket, said toothed wheel meshing with a pinion driven from said engine, in order to drive said sprocket at a speed considerably lower than that of said engine.

12. Apparatus as set forth in claim 11, wherein means are disposed between said engine and said chain driving sprocket for driving said chain and therefore the apparatus according to a suitable speed range.

* 4: a: i I

Claims

2. Apparatus as set forth in claim 1, wherein said transmission member consists of an endless roller chain passing over said driving sprocket and over a return sprocket mounted for loose rotation in a bearing carried by the case of the apparatus, said endless roller chain carrying on its outer side face a crankpin on which one end of a connecting-rod is mounted for free rotation, the other end of said connecting-rod being pivoted to said connecting arm coupled to said control lever of the apparatus.

5. Apparatus as set forth in claim 4, wherein said quick-release apparatus consists of a strap having a collar-shaped end disposed around said control lever, the end of the connecting arm being pivoted to a transverse pivot pin carried by said strap, and being further adapted to be locked thereto by the engagement of studs or like projections carried by said strap into notches formed in a sleeve member adapted to slide on said connecting arm and to be set in any desired and suitable position therealong by means of set screws.

9. ApparAtus as set forth in claim 8, wherein said quick-release coupling device consists of a strap rigid with the control lever of the apparatus and adapted to co-act with the end of said hollow connecting-rod, said strap carrying an eccentric the operation of which causes the engagement of teeth carried by said strap with corresponding teeth carried by said hollow connecting-rod.