US2678188A - Return and counterbalance device for detachable gooseneck trailers - Google Patents

Description

May 11, 1954 ROGERS 2,678,188

RETURN AND COUNTERBALANCE DEVICE FOR DETACHABLE GOOSENECK TRAILERS Filed Oct. 24, 1950 2 Sheets-Sheet l E7 INVENTOR.

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May 11, 1954 H. L. ROGERS 2,678,188

RETURN AND COUNTERBALANCE DEVICE FOR DETACHABLE GOOSENECK TRAILERS Filed Oct. 24, 1950 2 Sheets-Sheet 2 IN V EN TOR.

Patented May 11, 1954 UNITED STATES PATENT OFFICE RETURN AND COUNTERBALANCE DEVICE Fog DETAGHABLE GOOSENECK TRAIL- ER Hugh L. Rogers, Albion, Pa., assignor to Rogers Brothers Corporation, Albion, Pa., a corporation of Pennsylvania Application October 24, 1950, Serial No. 191,884

it toward, startin position after the element has ing characteristics.

been moved by an applied extraneous force out In many structures, especially where the heavy of starting position against the resistance of the e m t s be returned s o y to Starting D de ice. sition, shorter springs are impractical. Since lit- More specifically, the present invention relates tle dynamic inertia can be imparted to the eleto the combination of such a device with a delo ment by the highly stressed spring, the assistance t habl gosseneck of a heavy duty hi h a of any coasting effect of the element in the last trailer, as a result of which a ground engaging -8 f etu is lacking. Consequthtly, the ram, mounted on th o seneck, i lifted nd r spring must retain sufiicient restorative force, stored to starting position above the ground level even when it is almost restored to normal and after the gooseneek, which has been hoisted by the element is almost to fully rn d po i n forcing the ram downward against the ground, to force the element to fully returned position. is coupled to the body of the trailer. a h rt pr a large m un of For the purposes of illustration, the device is the pows q d when the heavy element is described i i t o th detachame moved near to its maximum distance from startgooseneck and lifting ram of a highway trailer, o Overcome e then highly Stressed Spring such as more fully disclosed in the application as Well as ue the movement of the eleof Clyde C. Keesler, Serial No. 134,818, filed Dementcember 23, 1 49, and entitled .Power Manipu- The same gen ra y is true of other resilient lated Detachable Gooseneck for Trailers, (now restoring means.

United States Letters Patent No. 2,590,181, issued A e al l'e ll he present i v t on is to Mar h 25, 1952), in whi h ombinati n it h interconnect such an element and the resilient special applicability and advantages, its applirestorin means by a mechanism such that the cation to other apparatus and other purposes restorative force app y e restoring eans being readily apparent from the illustrative exe eme t Changes more gra y than t ample restorative force of the resilient means itself.

In returning reciprocating or oscillating ele- Another general ObjECt is 3 make p ssi e the ments of a machine or apparatus to startin pouse of a Shhrter Spring by virtue of this more m ili t n h as t i or efficient application of its restorative force and pression springs are commonly used and conby so arranging the mechanism that the amount nected directly (or by a lever) to the element to as f el n a n or c mp i s the case y be moved. However, where the element to be re- 0f e es l ent means is less than the travel turned is relatively heavy or its return is re- 0f the element from St g p sition to maxistricted by relatively high frictional or other mum displaced PO t forces, very strong springs must be used. This is In g the present device itself p s not objectionable if the distance the element is 40 a rotatable a motion translating means to be returned is relatively short but, as the discperativcly connected to the rotatable means and tance is increased, the difficulties of obtaining adapted. to be connected to an element to be osproper spring return action are increased. This cillated or reciprocated so that when the element is due in part to the difficulty of providing a large is moved from a starting p s by a extraneheavy spring capable of producing a sufficiently ous force, the rotatable means is rotated in one uniform pull or push throughout the high degree direction and, when the rotatable means is roof elongation or compression necessitated by the tated in the opposite direction, it returns the elelon return distance. Usually the restorative ment to startin position. A rotatable connectforce of such springs is fairly uniform only lllg means is operatively wnnected to the rothroughout a relatively small increment of its tatable means for rotation in a predetermined total deflection, as a result of which a much fixed relation thereto and is connected to the longer spring is required where fairly uniform resilient means in a relation such that, upon restorative forces are required than would be removement of the element away from starting quired otherwise. position, the resilient means is progressively However, space limitations often preclude the stressed by the rotatable connectin means and 2 use of a spring of sufficient length. Further the cost of such springs is considerable. Accordingly, a compromise is usually made, using a shorter spring despite its less desirable operatthe restorative force of the resilient means resists rotation of the rotatable means by bein applied to the connecting means in spaced relation to the axis of rotation of the connecting means in a plane normal to said axis of the connecting means at a mechanical advantage which decreases progressively as the restorative force of the resilient means itself increases and which increases progressively as said restorative force decreases, whereby the translated force applied by the translating means to the element changes more gradually than the restorative force of the resilient means itself.

A preferred and specific embodiment of the device comprises a rotatable winding drum to which, as a motion translating means, one end of a flexible cable, to be connected to an element to be returned to starting position by the device, is connected in fixed position and about which the cable is wound. A connecting means in the form of a spiral winding drum is connected to the first drum for rotation therewith, either directly or through suitable gearing or otherwise, so that the two drums rotate in predetermined fixed relation. A cable is connected by one end to the spiral drum and is wound about its spiral periphery, the other end of the cable being connected to a self-restoring resilient means such as a spring. The two cables thus are connected so that upon stressing the cable on the first drum so that it rotates the first drum and unwinds, the cable of the spiral winding drum is wound on the spiral drum, thus stressing and elongating the spring. The peripheral spiral Wall of the spiral drum is so positioned circumferentially of its axis of rotation that, from the starting position for unwinding the wound up cable on the first drum, the cable of the spiral drum is operating at one of the longer radii of the spiral peripheral surface, and as the first drum continues rotation in the direction of unwinding of its cable, the spiral drum is rotated so that its cable engages the spiral peripheral wall at portions of progressively shorter radius. Thus, when the spring is only slightly stressed, it operates to urge the winding drum in the return direction by applying its restorative force at the end of a long lever arm and as its restorative force increases, due to further rotation of the drums in the same direction, this restorative I force is applied to the spiral drum at a progressively shorter lever arm. Accordingly, the mechanical advantage in the restorative force of the spring as applied to the first drum decreases as the stress of the spring increases and increases as the stress of the spring decreases due to the progressive variation in the lever arm.

In addition to the advantages which are apparent from the foregoing general description, the device has the advantage of connecting the return spring to a part to be returned thereby in such a manner that the amount of elongation, or compression, as the case may be, of the spring can be made much less than the distance of travel of the part to be returned.

By varying the size or degree of spiral of the spiral peripheral wall, the strength of the spring in relation to the element to be returned to starting position, the diameter of the first drum, and gearing therebetween, if used, or any one of these factors, the device can be adapted readily for positively returning an element to, or part way to, starting position, or for merely counterbalancing the element in whole or part, or for obtaining a wide range of relations between the elongation or compression of the spring and travel of the element.

Other objects and advantages will become apparent from the following description, wherein reference is made to the drawings, in which:

Fig. 1 is a fragmentary longitudinal sectional view of a detachable gooseneck trailer with the device of the present invention installed and is taken on line l-l in Fig. 2, part thereof being shown in elevation for clearness in illustration;

Fig. 2 is a cross sectional view taken on the line 2-2 of Fig. 1, part thereof being shown in section for clearness in illustration;

Fig. 3 is an enlarged side elevation of the device of the present invention, showing the relation of the parts thereof when the element to be returned, or counterbalanced, thereby is in starting position;

Fig. 4 is a view similar to Fig. 3 showing the relation of the parts of the device when the element has been moved away from starting position to the end of its path of travel;

Fig. 5 is an end elevation of the device as illustrated in Fig. 3 as viewed from the line 5-5 thereof; and

Fig. 6 is a diagrammatic illustration of a modified form of the invention.

Referring first to Figs. 1 and 2, the detachable gooseneck structure with which the device is shown combined, this structure, as more fully described in said copending application, comprises a trailer having a load supporting body I, the forward end only of which is shown and the rear end of which is supported on wheels in a well known manner. The body I has a. pair of forwardly protruding longitudinal sills 2 which are spaced apart transversely of the trailer, and by which the body is connected to a detachable gooseneck.

The gooseneck may comprise the usual rigid upright side members 3 which are spaced laterally of the trailer from each other and to the upper ends of which are secured forwardly extending horizontal members d. All of these members may be constructed in whole or part of suitable I-beams, or structural steel elements, or they may be fabricated of suitable plate steel portions welded together. Bridging between and connecting the upright members 3 near the rear thereof are suitable plates 5. The plates 5 preferably are welded at their edges to the edges of the bottom flanges of the members Li and to the rear margins of the upright members 3, thus providing a transversely rigid structure. Suitable reinforcing gussets 6 may be provided between the forward portion of the upright members 3 and the horizontal members 4. The gooseneck thus fabricated is very rigid.

Secured to the lower edges of the upright members 3, respectively, are sockets, indicated generally at 1. Each socket l is open at the rear and at least partially open at the bottom. Each is formed of a top plate 8 and rearwardly diverging side plates 9. which guide the forward ends of the sills 2 into the sockets, respectively. Fixedly secured between the lower portion of the plates 9 is an upward facing coupling member H), the upper or bearing face of which is preferably cylindrical. The forward ends of the sills 2 are provided with a downwardly facing coupling member H which is complementary to and engages the coupling member for rockingly connecting the gooseneck on the forward ends of the sills 2. Pivotally secured to the outboard side walls 9 of the sockets, respectively, by means of hinges I2, are looking plates I3. The plates 5 terminate downwardly above the level of the sills 2 and the locking plates I3 are adapted to be swung about their hinge I2 into position between the lower edge of the plate 5 and the top surfaces of the sills 2, respectively, when the gooseneck is raised above its normal connected position slightly so that when the gooseneck is then lowered to normal connected position, the plates I3 are interposed between the plates 5 and sills 2, thus preventing further downward movement of the rear of the gooseneck relative to the sills and holding the gooseneck and trailer in coupled relation. In this manner the gooseneck is connected to the sills for normal operation.

As fully described in said copending application, but not illustrated herein, the underside of the forward end of the gooseneck is adapted to rest on the upper face of the usual tractor fifth wheel, which is rockable about an axi extending transversely of the tractor, and to be connected thereto by an upward pivot or king pin. Thus, assuring the bed of the trailer is disconnected from the gooseneck and the forward end of the trailer is resting on the ground, the coupling is made by lowering the rear of the gooseneck until the coupling elements III are below the level of the elements I I, whereupon the tractor is backed to position the elements In into place beneath the elements H. The gooseneck is rocked forwardly about the fifth wheel axis so as to lift the elements It and cause them to engage with the elements II. Further forward rocking lifts the elements It and forward end of the trailer sulficiently high so thatthe plates I3 can be interposed between the plate 5 and the sills 2. Thereupon the gooseneck is lowered to normal connected position.

In order to lift and lower the gooseneck, it is provided with suitable vertical slideways, indicated at I d, between which is mounted a vertically reciprocable lifting ram I5 having a ground engaging foot I6 connected thereto by suitable transverse pivots. Mounted for rotation on a shaft I; which is secured in fixed vertical position on the ram I5 are a plurality of independently rotatable sheaves I8. Mounted in suitable supports I9 in fixed position on the gooseneck is a transverse shaft on which a plurality of independently rotatable sheaves 2I are mounted, these sheaves being rotatable about the shaft. A cable 22 is fixedly secured at one end to ends of the supports I9, is passed successively about the sheaves I8 and 2I and thence under a pulley 23 and over a pulley 24, beyond which, at its forward end, it is connected to the usual reversible power operated loading winch, not shown, on the tractor.

Thus, upon winding up of the cable 22 by the winch, the sheaves and shaft I! are forced downwardly toward the shaft 20 and sheaves 2|, thus forcing the ram I5 downwardly and causing its foot to engage the ground and thereby hoist or lift the rear end of the gooseneck.

When the gooseneck has been lifted and coupled to the trailer sills, the ram must be returned to starting position. Since such trailers are very heavy, the ram, of necessity, must be very rugged and therefore is itself extremely heavy. Yet it is desirable that it be returned by suitable spring means. Since the travel of the ram is considerable, it is difficult to obtain a spring which, by direct action, can lift the great weight of the ram tothe amount desired, particularly when opposed by the large force necessary to return the cable over the large number of sheaves. This is complicated further by the fact that the spring must not impose too great a force on the cable 22 as the ram is moved downwardly and approaches its maximum lowered position. For example, such rams frequently weigh as much as 1500 to 2000 pounds and must have a travel of about two feet or more. Further, in the present instance, it is desirable that not merely the ram be partially or fully counterbalanced, but that the return means he sufliciently strong to positively return the ram to its fully raised position against the force of gravity and the frictional drag occasioned by the cable passing around the sheaves. Likewise, it must retain the ram in raised position even when the trailer is travelling over rough terrain.

In order to accomplish this result with the resilient return means, such as a spring, the device now to be described is provided, it being understood that, in the case of the detachable gooseneck, two identical devices are provided, one at each side of the ram, though one only of the devices is described in detail.

Mounted on the gooseneck in fixed vertical position is a horizontal shaft 25 on which is rotatably mounted a rotatable means such as a winding drum 26. Connected at one end to the drum 25 by means of a suitable clamp 21 is a cable 23 which is wound about the periphery of the drum and at its free end, indicated at 29, is connected to the lower part of the ram I5, preferably by means of the pivots which connect the foot It to the ram. The cable 28 thus provides a motion translating means for translating the rotary motion of the drum 26 into lineal motion of the lower end of the cable. If desired, the drum may be connected to the ram by other means, such as by a pinion gear rotatable with the drum 26 and drivingly engaging a rack movable with the ram I5, but the cable connection is particularly advantageous where space requirements are controlling.

Operatively connected to the drum 25 for rotation in predetermined fixed relation thereto is a connecting means in the form of a winding drum 30 having a spiral peripheral winding face. In the form illustrated, the drums 26 and 30 are directly connected for rotation together about a common axis of the shaft 25. However, they may be connected for rotation in fixed relation by suitable reduction gears or other means, if desired. Connected by one end to the drum 35! by means of a clamp 3| is a cable 32 which is wound about the drum 30 and passed about a suitable pulley 33 and, at its opposite end is connected'to a suitable resilient self-restoring means, such as a tension spring 34. Thus the drum 3? and cable 32 act as a connecting means between the winding drum 26 and the spring 34 so as to stress the spring upon rotation of the drum 25 in the direction for lowering the end 29 of the cable occasioned by moving the ram downwardly from its starting position. The cable 32, provides a translating means for translating the motion of the drum 26 into lineal motion. The spiral peripheral wall of the winding drum 3D is so pcsitioned circumferentially of its axis. of rotation that when the spring 34 is substantially unstressed, as indicated in Fig. 3, the force applied thereby through the cable 32 is operating at the end of the longer lever arms or radius of the spiral peripheral wall. As the ram I5 is moved downwardly, however, by extraneous force, as described, the cable 32. operates at the end of a progressively decreasing arm or radius of the peripheral wall until it is acting on relatively short radius of the spiral drum, a illustrated in Fig. 5. Thus, as the translating means or cable 28 is moved by the ram away from starting position, the spring is increasingly stressed but as it is increasingly stressed, its restorative force is applied for urging or rotating the drum 26 in the opposite direction at a progressively decreasing mechanical advantage due to the shortening of the radius of the drum 30. Accordingly, when the spring 34 is fully stressed and its restorative force is applied at the end of a short lever arm, nevertheless it imposes a heavy turning moment on the drum 26. As the spring continues to approach its normal restored condition, its restorative force is much less but is applied at the end of a longer lever arm, thus still imposing a relatively heavy turning moment to the drum 26. Accordingly, therefore, though the restorative force of the spring increases, or drops oil, very rapidly, the turning moment imposed thereby varies much less radically due to an offsetting change in the mechanical advantage at which it is applied. Furthermore, the length of the periphery of the spiral drum 30 between the starting and stopping position of the cable 32 may be considerably less than the length of the periphery of the drum 2% between the starting and stopping positions of cable 28. Accordingly, therefore, the length of cable 28 is unwound much more than the elongation of the spring. For example, in one size of trailer such as illustrated, the elongation of the spring is somewhat less than eighteen inches whereas the travel of the ram 55 is more than two feet.

While in the illustrative embodiment of the invention a tension spring has been shown as the self-restoring resilient means, obviously other self-restoring resilient means, for example, a compression spring, may be used for some purposes. In the case of a compression spring, it would be arranged as illustrated diagrammatically in Fig. 6.

As there shown, the ram 35 carries a rack 36 which is engaged by a pinion segment 3'1. The segment 3! is rotatable with a spiral cam. 38. The cam 38 is engaged by a cam roller or follower 39 which is carried by a rod M. The rod 40 is "iidable in guideways 4i and is urged toward'the cam by a compression spring 62. In the illustration, the ram 35 is lowered and the spring 42 fully compressed. Thus, upon release of the ram, the spring forces the rod downwardly so as to apply the roller 39 to the cam 38, causing the cam to rotate clockwise. This rotation of the cam 38 causes the pinion to lift the rack 36, thus lifting the ram. Due to the progressively greater radius of the part of the spiral cam to which the roller is applied as the rod moves downwardly, the mechanical advantage of the applied restoring force increases as the stress of the spring decreases with advantages heretofore described.

While I have described an embodiment of the invention and shown the combination thereof with the hoisting ram of a detachable gooseneck of a trailer, it is apparent that it has many other applications. As one example, it may be used in many types of machinery in which a heavy reciprocating, or oscillating, element is moved by power to one position and is to be returned by spring action and the like to starting position, particularly wherein the distance the moving part must travel is comparatively long in relation to the spring. Furthermore, it may be used in such an instance where the element is to be returned by power means and merely assisted by a return spring.

As another example, it may be combined with heavy doors, such as overhead doors commonly used in factories, service stations and the like, particularly when the distance of travel of the door is relatively great in relation to the elongation that can be obtained with a spring of economical size and cost. In such cases, it may be arranged to lift and fully return the door, or merely to counterbalance the weight of the door fully or partially.

In fact it has advantages in all installations where it is desired that a moving force to be exerted by self-restoring resilient means be more nearly uniform than that obtainable by direct application of the restoring force to the element a to be moved.

Having thus described my invention, I claim:

1. In a trailer structure of the character described, a gooseneck adapted to be connected to a trailer when the gooseneck is elevated to a predetermined level, generally upright guideways on the gooseneck, a ram for elevating and lowering the gooseneok and. reciprocable in the guideways, a transverse shaft carried by the upper portion of the ram, a set of independently rotatable, coaxial sheaves thereon, a shaft mounted on the gooseneck below and parallel to the first shaft, a second set of independently rotatable coaxial sheaves thereon, a cable connected to the gooseneck at one end extending about the sheaves, successively, whereby, upon pulling the cable the ram is operated for elevating the gooseneck and when the cable is released, the ram can be returned to starting position but is resisted by the drag of the cables and sheaves, a hoisting cable connected by one end to the ram, a rotatable winding drum on the gooseneck about which the hoisting cable is wound, a rotatable connecting drum having a spiral peripheral wall and mounted on the gooseneck and connected to the winding drum for rotation in predetermined fixed relation thereto, a return tension spring connected by one end to the gooseneck, a connecting cable connected at one end to the other end of the spring and at the other end to the connecting drum and wound about the spiral wall thereof, and said spiral wall being normally in a rotated position such that the connecting cable is operable to elongate the spring at a progressively decreasing rate upon downward movement of the ram at a constant rate.

2. The combination with a trailer member, a hoisting ram member mounted thereon for moving from a retracted position in which its lower end is spaced above the ground to an extended position in which its lower end engages the ground and lifts the trailer member, means for moving the ram member to extended position, of a rotatable drum on the trailer member, a cable wound thereabout and connected to the ram member so that when the ram member is moved from a retracted position the rotatable drum is rotated in one direction by the cable, and, when the rotatable drum is rotated in the opposite direction, it winds up the cable and thereby returns the ram member to retracted position, a tension spring connected at one end to the trailer member, a second drum on the trailer member and having a spiral peripheral wall and connected to the first rotatable drum for rotation in a predetermined fixed relation thereto, a second cable wound about said spiral wall and operatively connected at its free end to the other end of the spring whereby, upon movement of the ram member away from retracted position, the spring is progressively stressed, and the spiral wall being so arranged circumferentially of its axis of rotation that in the retracted position of the ram member the second cable engages the spiral wall at a portion of relatively long radius and as the ram member moves from retracted position engages the spiral wall at portions of progressively shorter radius, whereby a mechanical advantage is obtained which decreases progressively as the restorative force of the spring increases and which increases progressively as said restorative force decreases and the translating force applied to the first cable thereby changes more gradually than the restorative force of the spring itself.

3. The combination according to claim 2 characterized in that the radii and predetermined rotative relation of the drums are such that the lineal travel of the cable of the first drum is greater than the lineal travel of the cable of the second drum when the drums are rotated at said predetermined rotative relation.

4. The combination with a trailer member, a hoisting ram member mounted thereon for moving from a retracted position in which its lower end is spaced above the ground to an extended position in which its lower end engages the ground and lifts the trailer member, means for moving the ram member to extended position, of a pair of coaxial winding drums connected to one member for rotation together about a common fixed axis, cables wound on the drums, respectively, for winding and unwinding from their respective drums in inverse relation to each other, at least one of said drums having a generally spiral peripheral wall, resilient self-restoring tension means anchored at one end to said one member and operatively connected at the other end to the cable on one of said drums so as to be elongated thereby as the last mentioned cable is wound onto its drum by rotation of the drums, the cable on the other of said drums being connected to the other of said members for unreeling from its drum as the ram member is extended and for reeling onto its drum for retracting the ram member, and said drums being positioned in a rotated position relative to each other so that the retracting force effective on the ram member from the resilient tension means operates at a mechanical advantage which increases progressively as the restorative force of the resilient tension means decreases.

5. The combination according to claim 4 characterized in that the cable connected to the tension means is wound on a portion of said spiral ,wall and said portion of the spiral wall is positioned circumferentially of the drums so as to engage its associated cable at a portion of predetermined radius when the tension means is in normal low stressed condition and engages its cable at portions of progressively less radius when rotated in the direction for increasing the stress of the tension means.

6. The combination according to claim 5 characterized in that said spiral wall is of less radius throughout the major portion of its peripheral extent than the radius of the wall of the other drum.

7. The combination with a trailer member, a hoisting ram member mounted thereon for moving from a retracted position in which its lower end is spaced above the ground to an extended position in which its lower end engages the ground and lifts the trailer member, means for moving the ram member to extended position, and resilient self-restoring means for returning the ram member to retracted position, rotatable means on one of the members and having parts rotatable in fixed relation to each other, a force translating means operatively connecting one of said parts to the other of said members so that, when the ram member is moved from a retracted position, said one of the parts is rotated in one direction and when said one of the parts is rotated in the opposite direction it returns the ram member to retracted position, another force translating means connecting the self-restoring resilient means to the other of said parts so that upon movement of the ram member from retracted position the self -restoring resilient means is stressed by rotation of said other part in one direction and urges said other part to rotate in the opposite direction, at least one of said parts having a spiral peripherally exposed surface and being connected operatively to its force translating means for applying the force of its force translating means at progressively changing portions of said peripheral surface so as to multiply the eifective force exerted by the self-restoring resilient means on the ram member.

8. A combination according to claim 7 characterized in that said parts of the rotatable means are coaxial and are connected for rotation together.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 146,675 Howell Jan. 20, 1874 268,545 Salisbury Dec. 5, 1882 902,768 Shockley Nov. 3, 1908 1,662,417 Cook et al. Mar. 13, 1928 2,590,181 Keesler Mar. 25, 1952 2,590,210 Rogers Mar. 25, 1952 FOREIGN PATENTS Number Country Date 72,025 Switzerland Mar. 16, 1916

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