Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16G—BELTS, CABLES, OR ROPES, PREDOMINANTLY USED FOR DRIVING PURPOSES; CHAINS; FITTINGS PREDOMINANTLY USED THEREFOR
  • F16G13/00—Chains
  • F16G13/02—Driving-chains
  • F16G13/06—Driving-chains with links connected by parallel driving-pins with or without rollers so called open links
  • F16G13/07—Driving-chains with links connected by parallel driving-pins with or without rollers so called open links the links being of identical shape, e.g. cranked
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16G—BELTS, CABLES, OR ROPES, PREDOMINANTLY USED FOR DRIVING PURPOSES; CHAINS; FITTINGS PREDOMINANTLY USED THEREFOR
  • F16G13/00—Chains
  • F16G13/02—Driving-chains
  • F16G13/04—Toothed chains
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H7/00—Gearings for conveying rotary motion by endless flexible members
  • F16H7/06—Gearings for conveying rotary motion by endless flexible members with chains

Definitions

• the invention relates to a chain transmission system comprising several form pieces connected with each other by points of articulation, and a wheel arrange ⁇ ment comprising at least one drive wheel for trans ⁇ mission of the chain of said form pieces.
• the bearing surface of the chain comprises preferably at least one opening formed by a pressure edge, a bottom and a trailing edge and arranged near the point of articula ⁇ tion, across the running direction and eccentrically in relation to the joint division..
• the openings of the chain are in co- operation with contact surfaces, such as sprockets or the like, being part of the drive wheel and arranged according to the openings, transversely to the running direction of the chain, the free contact width of the contact surfaces, such as the length of the sprockets, corresponding preferably to that of the form pieces.
• the width of the forming contact area corresponds preferably to the width of the form piece, after which cooperation, during straightening of the chain, the contact surface escapes from the opening at the trailing-edge side.
• the free inner diameter of each opening in the longitudinal direction is substantially greater than the contact length of the contact surface, such as the diameter of the sprocket.
• a chain structure partly of the above-mentioned type is previously known e.g. from the publication FI-64707 disclosing a form piece comprising an opening that is transverse to the running direction of the chain, has a length corresponding to the width of the form piece, and is advantageously placed near the second articulation point of the form piece.
• an advantageous lever arm is formed, thanks to which the chain force effective on the chain structure presses said openings more firmly towards the sprockets of the drive wheel.
• This solution reduces so-called jumping to a con ⁇ siderable extent.
• the lever arms formed the chain structure is easily released from the drive wheel, thus preventing so-called captivating.
• U.S. Patent 4,123,947 discloses a conventional chain structure manufactured of a non-metallic material.
• transmission from the drive wheel to the chain structure is usually carried out by a drive wheel with a standardized tooth system.
• a chain structure according to the publication FI-64707 has proved to be good in practice.
• plastic or corresponding non-metallic materials for the chain structures have been resorted to for reducing corrosion and the specific weight of the chain.
• said jumping has occurred, whereby the chain on the drive wheel, because of slight elongation or vibration of the chain or for another reason, rises from the sprockets of the drive wheel so that the drive wheel starts to rotate as its sprockets glide freely along the outer surface of the chain.
• the rotation of the drive wheel is stopped and the chain is placed over it again.
• the publication FI-85755 presents a more developed solu ⁇ tion.
• the improvement presented is based on the fact that during contact of the opening and the sprockets of the drive wheel, the free dimen ⁇ sion of the opening in the longitudinal direction of the chain is substantially greater than the correspond ⁇ ing measurement of the respective sprocket. The contact of said parts thus takes place between the sprocket and the pressure edge of the opening in the chain. Further, the greatest distance of the pressure edge from the central line of the form piece substantially exceeds the corresponding distance of the trailing edge.
• the chain transmission system of this invention is to provide a decisive improvement to the above-presented disadvantages and thus to improve the state of prior art substantially.
• the chain transmission system of the invention is primarily characterized in that the free inner diameter of the openings of the chain in the longi ⁇ tudinal direction is arranged to be changeable, wherein the openings of the chain of form pieces being at least in cooperation with the contact surfaces of the drive wheel, the free inner diameter of each opening in the longitudinal direction is at least partly changeable to be equal to the contact length of the corresponding contact surface, such as the diameter of the sprocket.
• the chain transmission system of the invention can be simplified and reliability, whereby all the above-mentioned problems, such as jumping and captivating, can be avoided.
• the chain according to the invention can be used with equal loading in both running directions. Thus no delay will be induced by a change in the running direction of the chain, but the chain will be im ⁇ mediately moved after a change in the direction.
• a form piece according to the invention can also be constructed so that the contact surfaces of the drive wheel are locked in the openings of the chain so that jumping becomes impossible in practice.
• Fig. 1 shows the operating principle of an advantageous transmission system according to the invention in side view
• Figs. 2a and 2b show an advantageous form piece according to the invention in side view and in front view.
• the chain transmission system comprises several form pieces 1 connected with each other at articulation points and a wheel arrangement which comprises further at least one drive wheel 7 for transferring the chain of said form pieces 1.
• the bearing surface lb of the chain comprises at least one opening 2 formed by a pressure edge X, a bottom Y and a trailing edge Z and arranged near the point of articulation, across the running direction and eccentrically in relation to the joint division.
• the open ⁇ ings 2 of the chain are in cooperation with contact surfaces 9, such as sprockets 9a, being part of the drive wheel 7 and arranged according to the open- ings 2, transversely to the running direction of the chain.
• the free contact width of the contact sur ⁇ faces 9, i.e. the length of the sprockets 9a, cor ⁇ responds preferably to the width 1 of the form pieces.
• the width of the forming contact area corresponds preferably to the width 1 of the form piece.
• the contact surface 9 escapes from the trailing-edge Z side of the opening 2.
• the free inner diameter e of each opening 2 in the longitudinal direction is substantially greater than the contact length of the contact surface 9, i.e. in the presented embodiment the diameter of the sprocket 9a.
• the free inner diameter e of the openings 2 in the chain in the longitudinal direction is arranged to be changeable, whereby the openings 2 of the chain formed by form pieces 1 being at least in cooperation with the contact surfaces 9 of the drive wheel 7, the free inner diameter e 1 of each opening 2 in the longitudinal direction is at least partly changeable to be equal to the contact length of the corresponding contact surface 9, i.e. the diameter of the sprocket 9a.
• each form piece 1 has two points of articulation 4, 5, of which the first one is ar ⁇ ranged as a solid projection 4 substantially narrower than the width 1 of the form piece and the second one as a fork 5.
• each point of articulation 4, 5 is advantageously provided with a hole 6 with equal size, whereby for formation of the chain, each point of articulation can be formed by placing said projec ⁇ tion 4 of the previous form piece between the fork 5 of the next form piece and by placing a joint pin or the like in said holes 6.
• the inner diameter e of the openings 2 in the longitudinal direction of the chain formed by form pieces 1 is arranged to be changeable upon revolution of successive form pieces 1 in relation to each other at joints 4, 5 to be at least partly smaller e" than the contact length of the contact surfaces 9, at least when the chain is fully bent over the drive wheel 7.
• the pressure edge X of each opening 2 is arranged in the first form piece and the trailing edge Z in the second form piece as seen in the running direction of the chain, whereby the bottom Y of the opening 2 is arranged at least partly in the area of the joint 4, 5.
• the form piece 1 comprises, as shown e.g. in Fig. 2a, a pressure edge X at its second point of articulation 5 and a trailing edge Z at its first point of articulation 4, respectively.
• the form piece 1 shown in Fig. 2a is formed symmetrical in relation to its central point K, whereby the pressure edge X and trailing edge Z arranged in the points of articula ⁇ tion 4, 5 of the form piece 1 are substantially identical in form.
• the bottoms Y of the opening 2 at the points of ar- ticulation 4, 5 of the form piece 1 are connected to the pressure edge X and trailing edge Z in the form piece by a radius corresponding substantially to the form of the contact surfaces 9, such as the curvature of the sprocket 9a.
• the bottoms Y of the opening 2 in the form piece 1 are further arranged parallel to the central line s connecting the holes 6 of the form piece 1.
• the pressure edge X and trailing edge Z at the points of articula ⁇ tion 4, 5 in the form piece 1 are arranged to be partly straight, whereby as gliding a contact as possible is achieved between the sprockets 9a of the drive wheel and said pressure and trailing edges X, Z.
• the bearing surface lb of each form piece 1 is arranged to be at least partly hollow, such as in a form corresponding to the radius r3 of curvature of the drive wheel 7.
• the pressure edge X and trailing edge Z at the first and second point of articulation 4, 5 are arranged to join the bearing surface lb of the form piece 1 in a rounded v way.
• a form piece with a curved form in all parts as seen in side view as well as a chain is obtained, whereby point ⁇ like loads on the wheel arrangement are eliminated.
• the chain will not tend to carry e.g. material or impurities coming into contact with it in an unintended way.
• the parts of the chain transmission system of the invention can naturally be manufactured of a variety of materials, such as plastics, metals, composite materials, ceramic mate ⁇ rials and/or the like, by using a variety of methods.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Gears, Cams (AREA)
• Transmission Devices (AREA)
• Transmissions By Endless Flexible Members (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=8538140

Family Applications (1)

Country Status (4)

Families Citing this family (4)

Family Cites Families (2)

• 1993
  • 1993-06-16 FI FI932755A patent/FI91798C/fi active
• 1994
  • 1994-06-09 WO PCT/FI1994/000247 patent/WO1994029613A1/en not_active Application Discontinuation
  • 1994-06-09 EP EP94917014A patent/EP0704031A1/en not_active Ceased
  • 1994-06-09 AU AU68473/94A patent/AU6847394A/en not_active Abandoned

Non-Patent Citations (1)

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