Two way shock proof and absorbing towing coupling

Abstract: Two way shock proof and absorbing towing coupling, comprising two opposite planar chain holders (1), each holder having at least two equally spaced lugs; at least four pairs chain means, each pair comprising two chain sections, each chain section having a plate link and a joint connected by pin (4), two ends of each pair of said chain means being connected with the opposite lugs on said opposite planar chain holders by pins respectively; two towing frames (7) for connecting with two neighboring vehicles, each frame having at least two arms (9), each of said arms being connected pivotely with another end of each chain section in each pair of chain means, at least one shock proof bearing spring (8) provided between two planar chain holders and said spring being coaxial with the two towing frames (7), the two ends of said spring abutting against inner surface of said planar chain holders respectively, and a piston sleeve means (5, 6).

Description: This invention relates to coupling means provided between towing combination vehicles in water and land transportation, more particularly, to a two way shock proof and absorbing towing coupling according to the preamble of claim 1 (US-A 2,023,527). BACKGROUND OF THE INVENTION During the motion of transportation facilities, shock-vibration is the most detrimental to cause a mechanical structure to be loose, to have a short service life and even to be damaged. However, the problem of alternative two way shock-vibration along an axis of towing combination vehicles has not been solved simply and reliably until this invention is presented. One way buffer, therefore, cannot but to be used in the towing means of train, nine-haul truck, common truck, etc. Such one way buffer only provides time lag for starting, which is necessary in the starting process of towing combination vehicles, but it can not eliminate the great inverse shock caused by braking, especially emergency braking, and moving down along a slope, which affects seriously the service life and safety of transportation facilies. It is well known that because only one way shockproof buffer, which is effective when starting, is provided between railway carriages, great inverse shock will be caused by slight braking during motion, and summerization of great shocks between railway carriages caused by emergency braking or bumping of trains and in other situations will result in turning carriages over and in injuries and deaths of passangers. Such serious accidents have been repeatedly met with in the transportation in the world. The application of the two way shock proof and absorbing towing coupling enables the carriages not to be turned over when bumping, even in serious accidents, so as to decrease injuries and deaths, and reduce the lose, and may eliminate shock-vibration resulted from braking and running, so as to ensure smooth and steady motion, and increase service life of trains. Combination vehicles for highway transportation is an ideal way of transportation However, if one way buffer is still used as the towing coupling of said combination vehicles, such combination vehicles can't work normally because of the inverse shock of the towed vehicles on the leading vehicle and the bumping between the towed vehicles. Therefore, the key problem of that there have not been combination vheicles used as a real transportation tools for highway transportation so far is the technique of two way shock proof and absorbing towing coupling has not been provided. Rope connection has long been used in towing of ship. Some factors, such as wind-wave and variation of ship speed, result in speed difference and great and frequent two way shock between towboats. The shock stress is very great although some shockproof means, such as palm fibre packages, used tyres, and the like, are provided on ends of towboats. In order to decrease or buffer the bumping, distance between towboats should be enlarged. Thus, towing efficiency is decreased, and the energy is wasted. Therefore, two way shockproof is also a key problem to be solved pressingly in water towing transportation. While the boat anchors, a general method is to tie it to piles by ropes. For a big ship, complex facilities, such as the winch and steel cable, and heavy labour operations are necessary. Because of the great inertia, long and large ship body, and shake of the ship, the ship bumps the wharf violently. Although shockproof means, such as hanging pads made of bundles of rubber belts are used, the great bumping stress still results in the deformation of the ship body on its both sides. Therefore, one of difficult technical problems which need to be solved urgently for anchoring of ships and boats is how to solve thoroughly the two way shock which may cause disconnection and how to simplify the facilities for anchoring. To sum up, once two way shock proof and absorbing for towing transportation of various combination vehicles is solved, efficiency and benefit of transportation and service life and safety of transportation facilities will be increased greatly. US-A-2023527 discloses a two way shock proof and absorbing towing coupling comprising casing assembly and compression spring, the opposed members of the casing assembly being slidable relative to each other. However, such a coupling is easy to be damaged since a plurality of slide fittings are used in the apparatus. SUMMARY OF THE INVENTION The objective of the present invention is to solve simply and reliably the problem existing in prior art to provide a towing coupling for combination vehicles so as to increase transportation ability and save energy. In order to realize the above mentioned objective, the present invention provides a two way shock proof and absorbing towing coupling, comprising the features of claim 1. Preferably, said two planar chain holders are connected by four pairs of chain means. The axes of the lug holes of said planar chain holders may be parallel or perpendicular to the radial of said planar chain holders. Preferably, said arm of a towing frame is spaced with correspondent arm of another frame by an angle of 90°. The invention will now be described by way of example only and with reference to the accompanying drawings, wherein: Fig. 1 is a partially sectional plan view of coupling according to one form of the present invention; and Fig. 2 is a perspective view of the coupling of the present invention as shown in Fig. 1. The towing coupling of this invention comprises two planar chain holders 1; at least four pairs of chain means, each of which comprises of two chain sections, each chain section having a plate link 3 and a joint 2 connected by pin 4; a piston sleeve means 5, 6; two towing frames 7 for connecting with two vehciles; at least one shock proof bearing spring 8, etc. It can be seen from attached drawings, Figures 1 and 2. One end of piston 5 is inserted into sleeve 6, and shoulders at their other ends are respectively fitted in the center holes of the two planar chain holders 1, shock proof bearing spring 8 spirally surrounds the piston-sleeve means 5, 6, two ends of the spring 8 are in touch with the inner surface of the two planar chain holders 1 respectively, the other end 2a of each joint 2 of the chain means is connected with the hole of a respectively lug protruded from the planar chain holder 1, the other ends 3a of plate links 3 of the chain means are respectively connected with towing frames 7 by respective pins 4 each fixed in both holes in one plate link 3 and in one arm 9 of the towing frame 7. This forms the two way shockproof and absorbing coupling of the present invention, wherein toggle-action may be made by the chain means, and lugs 10 of the planar chain holders 1 and by chain means and towing frames 7. While the towing frames 7 are pulled in opposite directions by taking two shaft holes 7a on the two towing frames 7 as bearing points for load, chains means outside of arms 9 of towing frames 7 is forced, and two planar chain holders 1 connected respectively with said chain means are pressed towards the center. Thus, shockproof bearing spring 8 between the two planar chain holders 1 is pressed and is still in working condition, and chains means inside of the arms 9 of the two towing frames 7 bend for there is no force acting on them. While the pull force acting on the bearing points of towing frames 7 is instantaneously changed to a push one (or shock) towards center, chain sections inside of arms 9 of towing frames 7, from the unforced state to a forced one, pull respectively the connected planar chain holders 1 to move towards the center, the pressed condition of shockproof bearing spring 8 is change to an unforced condition, and then to the pressed condition again. The forced condition of chain means outside of arms 9 of towing frames 7 is then changed to the unforced bending condition. Therefore, while the condition of the towing couplings 7 is changed instantaneously from the pulled condition to the pressed condition, the shockproof bearing springs 8 still work in the pressed condition. During the change of the force, there is no shock causing disconnection, and the combination vehicles can bear the load safely and reliably, and absorb vibration caused by shock. Each pair of chain means bears no shock causing disconnection and can work safely and reliably during the change process of force. An embodiment of the two way shock proof and absorbing coupling of the present invention is one used in truck combination vehicles (A,B) for highway transportation, in which a truck of model Dong-Feng 140 made in China is used as the leading vehicle and connects two towed vehicles by the couplings of the present invention. After experiments of transporting coal have been made with the above-mentioned combination vehicles on highway, good results have been obtained as follows: 1. The total loading of the combination vehicles is about 22 ± 1 tons and it is increased by one thirds. 2. The behaviours of said truck combination vehicles during starting and turning are similar to those of single vehicle; there is no vibration caused by time lag while starting and driving back, and the minimum turning radius is about 6 meters. 3. Driver and passengers have no feeling of inverse shock while the truck's brake is applied suddenly or driving down along slope, and the safety distance needed for bracking of said truck combination vehicles in an emergency substantially equals that needed for braking of single vehicle. The safety and stability of transportation are improved. 4. The adaptability of said truck combination vehicles to the slope variations, curvature and layer of mud of highway, and bearing strength of bridges are similar to those of single vehicle. Besides, the truck combination vehicles may not affect the normal traffic and transportation on the highway. 5. The said truck combination vehicles can be driven over road with a maximum slope of about 25°, which is in conformity with the general demand on the vehicle driving on slope. It has been calculated that about 20-25% energy can be saved through using the coupling of the present invention, and that an increment of about 45% income can be made by using the truck combination vehicles connected with the couplings of the present invention. Using truck combination vehicles is an effective way to save energy, to increase the transportation ability and to solve the problem of heavy and busy transportation. More economic benefits may be brought about as it is widely used. ADVANTAGE OF THE INVENTION The advantage of the invention lies in that: it is easy to design and make various models and series of two way shockproof and absorbing towing coupling of the present invention according to the demands of different towing combination vehicles for land, water or air transportation, and for military or civilian transportation. Since the towing frame, planar chain holder, spring and chain means are common and simple mechanical parts, their processings are well known. The towing coupling of the present invention can be produced in batches, and forms complete sets with various transportation and towing means. For any kinds of towing combination vehicles in transportation, the two way shock proof and absorbing towing coupling of the present invention can assure time lag necessary for smooth starting, and absorb shock-vibration between combination vehicles during starting, and absorb effectively vibration caused by tossing or series connection during the motion, and absorb inverse shock caused by the rear vehicle bumping the front one during speeding down, braking, and moving down along a slope. The present invention enables the truck towing vehicles to be real transportation tool, the energy source to be saved and transportation efficiency to be increased, and the cost of truck transportation to be reduced to correspond to the cost of railway transportation, thus enabling the advantages of truck transportation (great flexibility, wide adaptability) to be well exerted.

Claims: A two-way shock proof and absorbing towing coupling comprising two towing frames (7) for connecting with two adjacent vehicles (A, B), at least one compression spring (8) and a casing accomodating said spring (8), characterized in that each of said towing frames (7) includes at least two arms (9), and said casing comprises two mutually opposed chain holders (1), each chain holder (1) having at least four spaced lugs (10); at least four pairs of chain means (2, 3, 3, 2), each pair of chain means (2, 3, 3, 2) including two chain sections (2, 3), each chain section (2, 3) having a plate link (3) and a joint (2) connected by a pivot pin (4), first ends (2a) of each of said chain sections (2, 3) being connected to opposite lugs (10) on opposite chain holders (1) by pivot pins (4), respectively, second ends (3a) of each of chain sections (2, 3) being pivotaly connected with each of said arm (9), and said spring (8) being provided between said chain holders (1) and being coaxial with said two towing frames (7), opposing ends of said spring (8) abutting against and between inner surfaces of said chain holders (1), respectively. The two-way shock proof and absorbing towing coupling according to claim 1, wherein said two chain holders (1) are connected by four pairs of chain means (2, 3, 3, 2). The two-way shock proof and absorbing towing coupling according to claim 1, wherein said at least two arms (9) of one of the towing frames (7) are spaced from arms (7) of another towing frame (7) by an angle of 90°. The two-way shock proof and absorbing towing coupling according to claim 1, further including a piston-sleeve assembly comprising a piston (5) and a sleeve (6) and extending between said holders, wherein said spring (8) substantially surrounds said piston-sleeve assembly.

Inventors: ZHAO ZHENDONG, ZHAO, ZHENDONG
Applicants: ZHAO ZHENDONG, ZHAO, ZHENDONG
Application year: 1989
Main classification: B60D1
IPC codes: B60D1, B61G9