JPS621865B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The relative capabilities of wheels and tracks as movable supports for motor vehicles have long been debated.
Generally speaking, many high-load vehicles, such as combat vehicles and industrial vehicles, have a wide footprint in contact with the ground, resulting in lower pressure per unit area and less weight distribution. Articulated trajectories have been utilized because they increase overall traction and the ability to support heavy loads. Such vehicles have advantages over wheeled vehicles, especially on off-road or rough terrain. but,
Its inherent disadvantages are that the weight of the track itself and the necessary suspension is relatively large, and the number of moving parts required is relatively large. These factors, of course, increase production costs, reduce reliability and maintenance costs, and lead to breakage in unfortunate cases such as combat situations.

It was proposed some time ago that a solution to some of the above-mentioned problems inherent in tracks was the use of loops made of flexible material and capable of considerable curvature, like a carpenter's folding rule. It was done. Examples of prior art proposals or publications in this regard include: French patent no.
No. 1443364 Levame, UK Patent No. 413729
Kitchen, US Patent No. 2661249 Bonmartini, Austrian Patent No. 97243 Egerton, "Automatic Landing Craft with Elastic Loop Suspension", German Aerospace Research Institute Bulletin June 1975, pp. 289-308.
Written by Wolfgang Trautwein.

To the applicant's knowledge, none of the schemes described in these related patents has proven successful, as improvements in design and materials have not allowed the full potential inherent in this scheme to be put to practical use. The problem was that the various support technologies had not yet been developed to the point where it could become a reality.

It should also be noted that although endless flexible loop tracks have been utilized in snowmobiles in recent years, these are not similar to the present invention for reasons discussed below. Applicant recognizes the inherent benefits of the loop track system, which, as discussed below, eliminates the disadvantages of traditional tracks while retaining its desirable characteristics, and provides a low-cost, high-reliability, military, industrial and We have developed and operated a track that is a versatile structure for use on the road as well as other off-road vehicles, and is compatible with lightweight commercial designs.

Applicant's loop trajectory is as stated here:
It includes at least two flexible and highly elastic "cores," each of which is shaped so that it can be thought of as a "barrel" shape, i.e., with a slightly smaller diameter at the edges than at the center of the core. The cores are circular rather than oval in the absence of loads or other restraints, and the cores are laminated with multiple "stud bands" of flexible, high strength, preferably metal. and the stud band extends laterally between the cores in a sandwich relationship and preferably extends from the edge to form an almost chain-like hole for receiving the gear teeth used to provide drive traction. ing. If desired, the outer surface of the outer core can be provided with a thick rubber or other flexible tread material, and edge protectors are provided for the dual purpose of holding the cores together and protecting them at the same time; A link mechanism is provided between the stud bands.

The new loop track mechanism described above is suspended or resiliently mounted from the vehicle by using at least one "swing arm", which swing arm is normally rotatably mounted on a frame substantially contained within the loop track. It is journalled and has a journalled load roller on the top of the swinging arm, which load roller normally serves to press downwardly against the loop track and thus to keep the loop relatively elongated. The rotatable nature of the swinging arms allows a compensating pressure engagement of the idler sprocket mounted between the swinging arms, which serves to automatically follow slack in the loop and maintain constant engagement with the loop track. give a match. Importantly, a damper can be used to dampen the motion of the swinging arm;
It is possible to damp a full suspension system.

As a subcombination, the core itself also constitutes a novel product, which, in addition to being ideally suited to construct the basic building blocks of the loop orbits mentioned above,
It has applications as a reinforcing element in tires.

The stiff and inherently circular loop track system provides distinct elasticity or flexibility in vehicle support and, by the nature of its construction, can provide significant weight support. Applicants have tested such laminated core loop tracks to support at least 337 Kg (750 lbs). Larger units can support many times this weight. The flexibility of the loop is increased by the fact that the drive sprocket and the idler sprocket are located some distance from the ground or the supporting surface of the vehicle to which it is attached, and therefore by the inherent flexibility of the loop core. Allows the drive sprocket and idler sprocket or other rollers to support the weight of the vehicle without contacting the ground. This eliminates the need for "bogie wheels" that have been needed to maintain a normal trajectory for the track vehicle and provide a more even spread of vehicle weight in contact with the ground. This ground contact is made and maintained in the loop track mechanism of the present invention due to the inherent flexibility of the loop track, thus significantly reducing weight, number of moving parts and cost, and increasing reliability. The load distribution of the vehicle is therefore transferred to the loop track via the two upper idler rollers and is evenly distributed over the large footprint on the opposite side of the loop.

The two curved sections at the front and rear of the loop track act as suspension "springs", providing large vertical deflections when subjected to dynamic loads. The inherent stiffness of the loop trajectory along the ground contact area has the effect of having numerous bogie wheels. The distribution of ground pressure provides excellent traction, especially when climbing hills and in loose ground or in remote areas such as fine sand, mud, etc. In addition to being lightweight, this feature also allows the loop trajectory of the present invention to provide an excellent power plant for extraterrestrial vehicles. This is particularly attractive as loop track suspensions have been calculated to reduce unsprung mass by approximately 40% over current track suspension systems.

Another feature of the loop track is that the above-mentioned flexibility and mounting give it horizontal as well as vertical resilience, and this makes it particularly useful in any type of vehicle where ground contact shocks are transmitted to the driver and passengers with little damping. It will add comfort to those people. It is also expected that the nicks and breaks caused by bullets, ore, rocks, etc., will be less likely to occur before catastrophic failure occurs, compared to normal trajectories with closely interlocking sections. Although it tends to cut a relatively small number of fibers out of many fibers, the inherent tensile strength and flexibility of the remaining fibers constitute a considerable durable strength that resists destruction of the whole. Damage to the loop trajectory can be sustained over a fairly large range. In this regard, JCShuart published an article in the ``Journal of Springs'' magazine.
In an article titled "The Role of Reinforced Plastics in Leaf Springs" in the April 1967 issue, it was shown that glass fiber reinforced epoxy maintained more than twice the strength of hardened and annealed steel. Ta.

Inherently, as a by-product of being lightweight and having fewer moving parts and low running resistance, fuel consumption is low.
Since energy conservation is considered to be an important factor, loop tracks have been adopted for a wide range of vehicles.

Applicants have also discovered that the stud band and attachment mechanism described below provides a sprocket engagement device that eliminates the need for punched holes in the loop track mechanism. It is believed that such pores significantly reduce the strength of the material from which the loop core is made.

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a loop track 1, which includes a generally inner fiber-reinforced composite core 2.
and an outer fiber-reinforced composite core 3. This disclosure contemplates any type of composite fiber or filament core impregnated with resin to maintain shape and provide strength to the fiber support, the choice of the particular material depending on the application. A description of one preferred process by which such a filament-wound core is made is provided below. Applicants have found that the choice of fiber and resin depends on the conditions of the particular application, but it has been found that graphite fibers or glass fibers impregnated with epoxy resin are generally optimal.

The composite core is formed to remain naturally and typically circular. It is important that these cores have a "barrel" shape, concave on one side and convex on the other, and that the inner diameter of the outer edge of the core is slightly smaller than the inner diameter of the central part of the core. It has been found that this shape increases the suspension and flexibility of the core and provides, in addition to the necessary strength, a more even weight distribution per unit area of the core. As will be appreciated, the outer diameter of the inner core and the inner diameter of the outer core must be made so that they mate concentrically with tolerances close enough to provide a proper mating.

The invention specified herein notes that, depending on the thickness of the individual cores and the application in which the particular loop track is installed, a number of such cores may be secured to each other, and at least two Consider a composite core.

A plurality of laterally extending stud bands 4 are sandwiched between the composite or filament cores 2 and 3. The stud band 4 is a generally flat elongated member with a screw 5 at each end.
It ends with It should be noted that the part of the stud band between the flat intermediate part and the screw 5 is formed into a thick annular shoulder 6. Applicant combines stud band 4 with composite cores 2 and 3.
It has been found that it is desirable to provide a thin elastic spacing layer 7 between the stud band and the composite core 2 and between the stud band and the composite core 3 as a fixing device. This strain barrier layer may be any suitable elastic material that will suitably adhere to the studband and composite core. Such a protective layer may also be provided on the inner surface of the inner core 2. The outer surface of the outer core 3 can optionally be provided with treads 8 of rubber or other desirable material to increase traction, reduce mechanical shock to the assembly,
Quieter operation and improved useful life are also possible. The tread surface 8 may be of any desired pattern or shape, including essentially smooth or unpatterned surfaces. However, a tread having a greater thickness at the outer edge of the fiberglass core than at the center will give an overall flatter footprint and more even distribution of ground pressure, whereas a concave inner surface and a convex outer cross section of the core will result in a more uniform ground pressure distribution. Help hold. As shown in FIG. 2, if desired, the tread 8 may be provided with reinforcements 9 to provide additional strength not only to the tread but also to the entire loop track assembly.
Such reinforcement helps prevent expansion of the tread 8 and improves the bonding and connectivity of other elements of the loop track.

A key element of the invention is the end cap 10, which may be a forging or a section of aluminum extrusion or other desired material. The end cap 10 includes a protective cover flange 11 adapted to extend over the linkage described below. On the other side of the central wall 12 are a lower leg 13 and an intermediate leg 1.
There is an upper channel and a lower channel formed by 4 and the upper leg 15. central wall 12
is provided with a pair of holes approximately in the center of the lower channel formed between the middle leg 14 and the lower leg 13, which holes are adapted to receive the screw 5 of the stud band 4 and the thick annular shoulder 6. It's getting old. The channel formed between the middle leg 14 and the lower leg 13, in addition to accommodating the stud band 4, also accommodates the composite cores 2 and 3 and the strain that can be provided between them. “Sandwich” formed by isolation layer 7
The dimensions are such that they allow for tight engagement.

The other channel formed between the intermediate leg 14 and the upper leg 15 of the end cap 10 is adapted to receive an outwardly extending shoulder 16 which is preferably integrally formed with the tread surface 8. Thus, in addition to being joined to the outer core 3, the tread 8 is attached to the assembly by the aforementioned engagement of the outwardly extending shoulder 16 in the aforementioned upper channel.

As you can see from the above, stud band 4
are mounted in isolated pairs by mutual engagement with end caps 10. This serves to maintain the studbands at a relatively constant circumferential spacing as far as the individual pairs are concerned. To provide perfectly equal spacing between all stud bands, inner chain links 17 are provided which are generally flat link members with holes near their ends. The holes are spaced apart by the same distance as the holes in the central wall 12, and when placed over the screws 5 of one of the two stud bands held together by each end cap, the stud bands 4 It becomes a link that can rotate and engage with everything. Preferably, stress washers 18 are utilized in making the above connections.

Each screw 5 of the stud band 4 has a protective cap 2 provided with an internal thread that engages the screw 5.
0 is set. Cap 20 has holding shoulders 2
1, on which an outer link 22 is installed. The outer links are arranged alternately in the stud band 4 and together with the inner links 17 form a complementary link arrangement for the function of the central wall 12. Preferably, a stress washer 23 is used at the attachment point of the outer link 22.

Between the inner link 17 and the outer link 22 a rotatable bearing roller 24 is journalled, thereby providing sprocket teeth 2 to be engaged.
It has been found desirable to provide a more flexible engagement surface for 5.

Preferably, the drive sprocket 26, which is journalled on the drive shaft 27, is provided with an annular shoulder 28 which extends below the end cap 10 to provide additional support to the studband and core coupling assembly. It is adapted to engage with the legs 13 of the.

The above mechanism is equipped with a protective cover for the link mechanism,
And, in particular, the ease of manufacture and assembly of the parts provides a means of further increasing the structural integrity between the inner and outer cores 2 and 3 and the stud bands 4. The inner links 17 provide a means of absorbing stress and keeping the stud bands 4 in circumferentially equidistant relation.

A preferred method of manufacturing the inner and outer filament wound cores will now be described with reference to FIGS. 5, 6, 7 and 8. 5, the shaft 30 of the winding machine includes a segmented male mandrel 32.
Adjustable spokes 31 are provided to aid in the mounting of the mandrel, and the mandrel is provided with an annular shaped overhang ring 33 providing a mounting surface on which the cross plies of fabric material 34 are placed. The cross plies 34 are related to the longitudinal axis of the wrapping machine shaft 30;
It may be mounted parallel to the shaft or at a selected bias angle as desired to meet the requirements of a given application. Preferably, at least a portion of the outer peripheral surface of the overhang ring 33 is provided with a plastic liner 35.
is provided.

After placing the cross ply 34 on the mandrel, the wrapper shaft is rotated to successively receive the surrounding fibers 36. Various winding machines known in the art or within the skill of those skilled in the art may be utilized to impart rotational motion of the mandrel as well as axial movement, thereby causing the surrounding fibers to 36 is wound on the mandrel like a fishing line wound on a reel on average. The binder or impregnant may be applied at the same time the surrounding fibers 36 are placed on the mandrel, or such materials may be added later by methods known in the art. Once sufficient circumferential fibers 36 have been placed on the mandrel to achieve the desired thickness, the layers of cross plies 34 are folded around what will become the longitudinal plies or "inner" core of the fibers, as shown in FIG. or rolled up and secured thereto in any suitable manner using adhesives, clamps, or the inherent properties of the binder/impregnant, if used.

Applicants have determined that a preferred method of fixation includes providing an additional surrounding fiber layer or layers to constitute an outer layer 37 of such fibers, such layers being susceptible to subsequent processing. It has been found that there is a dual benefit of including cross-ply layers for the composite and increasing the strength of the composite.

Another way to wind the core is to use the inner cross plies 34.
is wound to the correct width of the loop core without overhangs, with rapid axial movements as the winding machine rotates, as is known in the prior art of wound bias plies. Once the desired number of inner core plies have been wound, the winder is configured to wind the surrounding fibers 36 onto the mandrel. The outer cross ply 34 is then wound in the same manner as the inner cross ply described above.

Other winding methods reduce manufacturing costs and are more suitable for mass production.

FIG. 8 shows the core member removed from the male mandrel 32 and placed within the female mandrel 38, the core member being secured to the female mandrel by a plastic liner 35, the liner being e.g. attached to the female mandrel by. The liner thus remains in the desired shape during the cycle in which the impregnating agent is cured according to the nature and properties of that particular impregnating agent.

Once the two or more cores constructed by the above process are completed, they can be assembled into stud bands and other hardware to have an essentially constant concave inner, convex outer cross-section. and usually forms a circular loop trajectory.

Core assembly begins by assembling the next largest core into the largest core. This is accomplished by using a fitting that transforms the smaller core into a shape similar to a heart shape. This allows the smaller core to be easily inserted into the larger core. The smaller core is then allowed to assume its normal shape and mate properly inside the larger core. This process allows for the subsequent insertion of additional smaller cores, if needed, to create a loop trajectory of the desired strength of the desired number of cores.

The composite core configured as described above can run on conventional automobile tires with a flat tire, so-called “run”.
-flat” performance. When an inflatable tire goes flat, the core provides supporting strength. This, of course, minimizes damage from sudden tire depressurization and allows the vehicle to be repaired or safe. Allows you to advance to a certain point.

FIG. 9 shows a loop trajectory constructed according to the above-mentioned matters, and mainly includes a basic frame 40 that can become a part of the chassis of a vehicle.

The drive wheel 41 is rotatably journalled within a loop track between the side walls of the base frame 40. The drive wheel 41 is provided with gear teeth forming a pair of drive sprockets 42 which engage the loop track mechanism in the manner described above. The actuators for driving drive wheel 41 and drive sprocket 42 are not shown but are considered to be within the skill of the art. Obviously, such devices are internal combustion engines, electric motors, etc. connected to the drive wheels via a power train in the state of the art.

A passive load roller 43 is journalled at a predetermined position between the side walls of the base frame 40 to bear the weight of the vehicle's chassis.

At the opposite end of the base frame 40 is a swing arm 45 journalled between its side walls. The swinging arm 45 preferably includes a rotation damper 46
The base frame 40 is journalled between the side walls 44 of the base frame 40 via the base frame 40. The swinging arm 45 mainly comprises a pair of end walls 47, with a portion of each end wall extending outward and upwardly around the loop track 1, and arranged to have a journalled active load roller 48 therebetween. be done.

Load rollers 43 and 48 may be identical in construction and have inner axial surfaces capable of rolling over the outer circumference of end cap 10B. The rollers are provided with a roller flange 49 at each end which prevents movement along the edge of the loop track and thus complements the engagement of the sprocket loop track in the transmission of side loads; It thereby plays an important role in significantly increasing stability.

The end wall 47 of the swing arm is generally triangular;
The remaining apex areas of the end walls are adapted to journally support an idler sprocket 50 therebetween;
Note that the idler sprocket is constructed similarly to drive sprocket 42 and similarly includes teeth that engage the linkage described above.

FIG. 9 shows a normally circular loop trajectory 1,
It is generally oval in the installed condition, but when compressed by suitable equipment it assumes the desired shape and is held in that shape by load rollers 43, 48, drive sprocket 42 and idler sprocket 50. Such compression of the loop trajectory provides a more uniform distribution of weight per unit area over the portion of the loop trajectory that contacts the ground than if the shape remained relatively circular.

Sprockets 42 and 50 are each located near the center of the end of the ellipse formed by the looped track and inherently allow the track to deflect vertically when subjected to obstructions or pressure. Additionally, the curvature of the loop track and the mounting of the sprocket above the ground provides a degree of longitudinal flexibility inherent in such loop track mounting systems.
This flexibility is enhanced by the swing arm 45 automatically adjusting to accommodate the expansion and contraction of the loop trajectory as it is actuated. Therefore, when relatively large ground loads (G-loads) are transferred from the vehicle to the loop track via the base frame 40, the swinging arm 45 is first moved by the lever pivoting about the axis of the active load roller 48. The load rollers simultaneously exert a relatively large compressive force on the loop track 1. The action of this lever causes the swinging arm 45 to generally carry or push the idler sprocket 50 outward to accommodate the change in the ellipse of the loop trajectory, maintaining a constant engagement of the two sprockets with the loop trajectory, thus making the comparison Maintains constant tension and prevents the raceway from coming off the sprocket. When the pressure or G-force is released, the opposite will of course occur and the loop trajectory will take on a nearly circular shape.

Therefore, the installation of the track via the foundation frame 40, which takes advantage of the inherent flexibility of the loop track 1 and the swinging arms 45, is of high strength, light weight, relatively low cost,
Provides a durable mechanism that can be used at high and low speeds on smooth as well as rough ground, exerts low ground pressure per unit area, and provides the rider with an often critical and significant Provides comfort and makes the device low impact.

Although specific and preferred embodiments of the invention have been described herein, it is to be understood that the scope of the invention is to be defined by the breadth of the claims appended hereto.

[Brief explanation of the drawing]

1 is a perspective view of a loop track mechanism constructed in accordance with the teachings of the present invention; FIG. 2 is a cross-sectional view of a portion of the loop track showing how the sprocket assembly is engaged; and FIG. 3 is a cross-sectional view of a portion of the loop track. Figure 4 is a top view of the loop track mechanism; Figure 5 is a diagram showing the mandrel and its first stage in the fiber-reinforced composite winding process; Figure 6 shows that the intersecting plies are connected to the surrounding plies. FIG. 7 shows the second stage of the winding process being wrapped around the inner core of the core, FIG. FIG. 8 shows the final manufacturing step in which the core is heat cured to the desired "barrel" shape, and FIG. FIG. 3 is a side view of a loop track attached to a support mechanism inside the loop. In the figure, 1... Loop track, 2, 3... Composite core, 4... Stud band, 10... Engagement device (end cap), 11... Protective device, 36...
Fiber, 5...Screw, 6...Shoulder, 7...Strain isolation adhesive layer, 8...Tread surface, 12...Central wall, 1
3, 14, 15...legs, 17...inner links,
20...protective cap, 22...outer link,
24...Bearing roller, 25...Sprocket teeth, 32...Male mandrel, 34...Cross ply layer, 37...Additional fibers, 40...Foundation frame, 42...Drive sprocket, 43...
Load roller, 45... Swing arm, 46... Cushioning material, 47... End wall, 48... Load roller, 50...
...play sprocket.

Claims (1)

Claims: 1. A loop track forming a movable support for a vehicle, comprising at least two concentric composite cores,
Each said core is formed from fibers bound together by a binder and further includes a stud band extending laterally between said cores and an engagement member attached to each end of said stud band for receiving sprocket teeth. A loop track comprising a device and a protection device connected to the end of the stud band and covering and forming part of the engagement device. 2. A loop track according to claim 1, wherein the track is normally circular when unstressed and has a generally concave cross section on one side and convex on the other side. 3. The loop track according to claim 2, further comprising an elastic strain isolation adhesive layer between the stud band and the core. 4. A loop track forming a movable support for a vehicle and its drive mechanism, comprising at least two concentric composite cores, each said core being formed from fibers bound together by a binder; a stud band extending laterally between the stud bands; an engagement device attached to each end of the stud band for receiving sprocket teeth; and a cover for the engagement device connected to the ends of the stud band. a protection device which is a part of the engagement device; a base frame provided at least partially within the periphery of the core; a drive sprocket that engages the device; a first load roller that is journalled in the frame and applies compressive pressure to the outer peripheral surface of the core; and a first load roller that is journalled in the core and rotatably supported on the base frame and that a swinging arm having an end wall extending beyond the circumference of the core; a second load roller journalled between the end walls and applying pressure against the outer periphery of the core; an idler sprocket journalled within a periphery and meshed with the engagement device, thereby absorbing the compressive pressure applied to the core by the load roller and the internal force of the core by the drive sprocket and the idler sprocket. A loop track and its drive mechanism, wherein the tension applied to the periphery is adapted to accommodate said core of flexible generally elongated working shape. 5. The loop track according to claim 4, wherein the swing arm is journalled by the base frame via a rotatable shock absorber, and its drive mechanism. 6. A loop track forming a movable support for a vehicle, comprising at least two concentric composite cores and a plurality of stud bands extending laterally between the cores, each said core having a circumferential comprising multiple layers of wound continuous fibers, and at least one layer of intersecting fibers disposed at a bias angle to and substantially surrounding said surrounding fibers, and extending around the outer periphery of said intersecting fibers; at least one layer of fibers wound around the circumference, the inner diameter of the edge of each said core being smaller than the inner diameter of the center of said core to give said core a barrel shape, and each said stud band an end cap terminating in a thread and having a thick annular shoulder between said thread and a generally flat portion extending between said thread and said core, and further including a central wall with two holes; a protective cover flange extending outwardly from a central wall beyond the threaded end of the stud band; and at least two legs extending inwardly from the central wall to define a channel; A portion of said core and adjacent pairs of stud bands are respectively inserted and included within said channel of each of said end caps, and an annular shoulder of an adjacent stud band is inserted into a hole in a central wall of said cap. , and a flexible tread fixed to the outer circumferential surface of the outer core, and an inner link inserted beyond said tread and located adjacent to the annular shoulder and between the stud bands of adjacent end caps. end retaining shoulders comprising members which, in alternating combination with said central wall, constitute the inner links of the chain to provide spacing between said stud bands, and further threadably engage the ends of said stud bands; and a generally planar outer link journalled in the protective cap and connecting between adjacent pairs of stud bands near the outer ends;
loop trajectory. 7. The loop trajectory according to claim 6, wherein the core is normally circular in an unstressed state and journalled by the protective cap between the inner and outer links. Loop track containing bearing rollers.