Dual rate jounce bumper and vehicle incorporating dual rate jounce bumper

Abstract

The invention relates to a dual rate jounce bumper (20) and a vehicle (26) comprising said dual rate jounce bumper.

Description

Technical Field

[0001] The present invention relates to dual-rate jounce bumpers and vehicles incorporating dual-rate jounce bumpers. Background Art

[0002] Jounce bumpers are used in a vehicle's suspension system to limit the transfer of impact forces to the vehicle's frame members. For example, when a vehicle rides over a bump, suspension system components (such as strut assemblies) buckle or collapse to absorb the energy generated by the impact. However, if the suspension system is unable to fully dissipate the energy, the suspension system components may strike the frame assembly, transferring the impact force to the vehicle frame members, which is undesirable.

[0003] Typically, jounce bumpers gradually stiffen the suspension system as it approaches the end of its jounce travel, that is, before suspension system components impact the vehicle frame. Consequently, conventional jounce bumpers serve to decouple suspension system components from the vehicle's frame to prevent the suspension system from directly impacting the frame. For example, a conventional jounce bumper may be coupled to a strut assembly's piston rod and the vehicle's frame. Conventional jounce bumpers decouple the strut assembly's cylinder from the vehicle's frame to prevent the cylinder from directly impacting the frame as the strut assembly approaches the end of its jounce travel.

[0004] US 9,545,829 B2 discloses a dual-rate jounce bumper comprising a bumper and an outer member. The outer member is disposed around the bumper and is capable of limiting radial expansion of the bumper as the bumper is compressed to increase the stiffness of the bumper. The outer member can also expand radially as the bumper is compressed.

[0005] WO 2017 / 202620 A1 describes a smooth stiffness profile when a spring element begins to compress. The support ring described therein increases the stiffness of the spring element as compression increases and serves to ensure highly progressive compression behavior. To this end, the support ring is made of an elastomer with a Shore A hardness of 45 or higher, particularly 75 ± 5.

[0006] Another US patent application, US 2010 / 0213656 A1, describes a jounce bumper assembly for a vehicle suspension system, comprising a jounce bumper coupled to a second bumper and a striker cap having a first end, the first end comprising a first cylindrical inner surface circumferentially coupled to a first cylindrical outer surface and having a second end configured to resiliently engage the jounce bumper. The striker cap is a load management cap designed to deflect and absorb energy, i.e., to increase deformation of the jounce bumper.

[0007] While existing suspension systems, particularly jounce bumpers, offer various alternatives for minimizing noise, vibration, and harshness (NVH) in vehicles, they still have several limitations. One such limitation is minimizing or preventing vehicle body roll, particularly when carrying heavy loads. Existing jounce bumpers are only suitable for vehicles carrying loads up to 70 kN, and can cause suspension overtravel when exceeding this load. Furthermore, improper material selection for jounce bumpers can lead to breakage at higher loads, significantly increasing their weight and overall cost.

[0008] It is therefore an object of the presently claimed invention to provide a dual rate jounce bumper for limiting jounce travel in a vehicle body that is capable of withstanding loads up to 150 kN, minimizes NVH, prevents suspension overtravel, reduces weight and is cost effective. Summary of the Invention

[0009] Surprisingly, it has been found that the above objects are met by providing a dual-rate jounce bumper (20) comprising a bumper (40) and an outer member (50), wherein the outer member (50) is obtained by overmolding stainless steel with thermoplastic polyurethane having a Shore D hardness in the range of 50 Shore D hardness to 80 Shore D hardness as determined according to ASTM D2240-15e1.

[0010] Thus, in one aspect, the presently claimed invention is directed to a dual-rate jounce bumper (20) for limiting jounce travel between a first member (22) and a second member (24) of a vehicle (26), wherein the second member (24) is spaced from the first member (22) and movable toward the first member (22) along a jounce axis, the jounce bumper (20) comprising:

[0011] a bumper (40) having a first end (42) for coupling to a first component (22) and a second end (44) spaced from the first end (42) for contacting a second component (24), wherein the bumper (40) is compressible between the first component (22) and the second component (24) for limiting jolts, wherein the bumper (40) is radially expandable as the bumper (40) is compressed, and

[0012] an outer member (50) disposed about the bumper (40) and capable of limiting radial expansion of the bumper (40) as the bumper (40) is compressed to increase the stiffness of the bumper (40),

[0013] The outer member (50) is obtained by overmolding stainless steel with thermoplastic polyurethane having a Shore D hardness ranging from 50 Shore D hardness to 80 Shore D hardness measured according to ASTM D2240-15e1.

[0014] In another aspect, the presently claimed invention is directed to a vehicle (26) comprising a frame member (30) having a first portion (22), a suspension having a second portion (24), and the dual-rate jounce bumper (20) described above.

[0015] In yet another aspect, the presently claimed invention relates to a ring obtained by overmolding stainless steel with thermoplastic polyurethane having a Shore D hardness within the range of 50 Shore D hardness to 80 Shore D hardness as measured according to ASTM D2240-15e1, the ring comprising an upper surface, a lower surface, a first wall, and a second wall, wherein the upper surface and the lower surface are inclined toward each other, wherein each of the upper surface and the lower surface is an arcuate surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A perspective view of a suspension system (28) of a vehicle (26) including a dual-rate jounce bumper (20) is provided.

[0017] Figure 2 A front view of an embodiment of a dual rate jounce bumper (20) having an outer member (50) positioned on the bumper (40).

[0018] Figure 3 for Figure 2 A cross-sectional view of a portion of a dual-rate jounce bumper (20).

[0019] Figure 4 A front view of another embodiment of a dual-speed jounce bumper (20) having an outer member (50) seated on a bumper (40) having a plurality of protrusions (54).

[0020] Figure 5 for Figure 4 A perspective view of a dual-rate jounce bumper (20).

[0021] Figure 6 It is a perspective view of the outer member (50).

[0022] Figure 6a It is a top view of the outer member (50).

[0023] Figure 6b It is a cross-sectional view of the outer member (50) through the coronal plane (BB). DETAILED DESCRIPTION

[0024] Before describing the present compositions and formulations of the present invention, it should be understood that the invention is not limited to the particular compositions and formulations described, as such compositions and formulations may, of course, vary. It should also be understood that the terminology used herein is not intended to be limiting, as the scope of the present invention will be limited only by the appended claims.

[0025] As used herein, the terms "comprising," "comprises," and "comprised of" are synonymous with "including," "includes," or "containing," and are inclusive or open-ended and do not exclude additional, unrecited members, elements, or method steps. It should be understood that the terms "comprising," "comprises," and "comprised of" as used herein encompass the terms "consisting of," "consists," and "consists of."

[0026] In addition, the terms "first," "second," "third," or "(a)," "(b)," "(c)," "(d)," etc., in the specification and claims are used to distinguish similar elements and not necessarily to describe a sequential or chronological order. It is understood that the terms so used are interchangeable where appropriate, and that the embodiments of the invention described herein are capable of operating in other sequences than those described or illustrated herein. Where the terms "first," "second," "third," or "(A)," "(B)" and "(C)," or "(a)," "(b)," "(c)," "(d)," "i," "ii," etc., refer to steps of a method or use or an assay, there is no continuity in time or time intervals between the steps, i.e., the steps may be performed simultaneously or there may be time intervals of seconds, minutes, hours, days, weeks, months, or even years between such steps, unless otherwise indicated in the application set forth above or below.

[0027] In the following paragraphs, different aspects of the present invention are defined in more detail. Unless clearly indicated to the contrary, each aspect so defined can be combined with any one or more other aspects. In particular, any feature indicated as preferred or advantageous can be combined with any one or more other features indicated as preferred or advantageous.

[0028] References throughout this specification to "one embodiment" or "an embodiment" mean that the particular features, structures, or characteristics described in conjunction with the embodiment are included in at least one embodiment of the present invention. Thus, the phrases "in one embodiment" or "in an embodiment" appearing in various places throughout this specification do not necessarily all refer to the same embodiment, but may refer to the same embodiment. Furthermore, in one or more embodiments, the particular features, structures, or characteristics may be combined in any suitable manner, as will be apparent to those skilled in the art from this disclosure. Furthermore, while some embodiments described herein include some features included in other embodiments but not others, as will be appreciated by those skilled in the art, the combination of features of different embodiments is intended to be within the scope of the present invention and to form different embodiments. For example, in the appended claims, any of the claimed embodiments may be used in any combination.

[0029] Furthermore, ranges defined throughout this specification are also inclusive, i.e., a range of 1 to 10 means that the range includes both 1 and 10. For the avoidance of doubt, applicants are entitled to equivalents under applicable law.

[0030] One aspect of the present invention, embodiment 1, is directed to a dual-rate jounce bumper (20) for limiting jounce travel between a first member (22) and a second member (24) of a vehicle (26), wherein the second member (24) is spaced from the first member (22) and movable toward the first member (22) along a jounce axis, the jounce bumper (20) comprising:

[0031] a bumper (40) having a first end (42) for coupling to a first component (22) and a second end (44) spaced from the first end (42) for contacting a second component (24), wherein the bumper (40) is compressible between the first component (22) and the second component (24) for limiting jolts, wherein the bumper (40) is radially expandable as the bumper (40) is compressed, and

[0032] an outer member (50) disposed about the bumper (40) and capable of limiting radial expansion of the bumper (40) as the bumper (40) is compressed to increase the stiffness of the bumper (40),

[0033] The outer member (50) is obtained by overmolding stainless steel with thermoplastic polyurethane having a Shore D hardness ranging from 50 Shore D hardness to 80 Shore D hardness measured according to ASTM D2240-15e1.

[0034] Thermoplastic polyurethane (TPU)

[0035] In one embodiment, the Shore hardness of the TPU in Example 1 is in a range from 60 Shore D hardness to 80 Shore D hardness, or from 70 Shore D hardness to 80 Shore D hardness.

[0036] In another embodiment, the TPU in Example 1 is obtained by reacting:

[0037] (a) polyols,

[0038] (b) isocyanate, and

[0039] (c) optionally a chain extender.

[0040] Suitable polyols have an average functionality of between 1.9 and 8.0, or between 1.9 and 6.0, or between 1.9 and 4.0, and a hydroxyl number of between 10 mg KOH / g and 1800 mg KOH / g, or between 10 mg KOH / g and 1500 mg KOH / g, or even between 10 mg KOH / g and 1000 mg KOH / g. The polyol may be present in an amount of between 1 wt% and 99 wt%, based on the total weight of the TPU.

[0041] In one embodiment, the polyol is selected from polyether polyols, polyester polyols, polyether-ester polyols, or mixtures thereof.

[0042] According to the present invention, the polyether polyols have an average functionality of between 1.9 and 8.0, or between 1.9 and 6.0, or between 1.9 and 4.0, or between 1.9 and 3.0, or even between 1.9 and 2.1, and a hydroxyl number of between 10 mg KOH / g and 1800 mg KOH / g, or between 10 mg KOH / g and 1500 mg KOH / g, or between 10 mg KOH / g and 1000 mg KOH / g, or even between 10 mg KOH / g and 500 mg KOH / g.

[0043] In one embodiment, the TPU in Example 1 is obtained by reacting:

[0044] (a) polyols having an average functionality between 1.9 and 2.1 and a hydroxyl number between 10 mg KOH / g and 500 mg KOH / g,

[0045] (b) isocyanate, and

[0046] (c) optionally a chain extender.

[0047] In another embodiment, the TPU in Example 1 is obtained by reacting:

[0048] (a) polyols having an average functionality between 1.9 and 2.1 and a hydroxyl number between 10 mg KOH / g and 500 mg KOH / g,

[0049] (b) isocyanate, and

[0050] (c) optionally a chain extender,

[0051] The polyol is selected from polyether polyols, polyester polyols, polyether-ester polyols and mixtures thereof.

[0052] In yet another embodiment, the TPU in Example 1 is obtained by reacting:

[0053] (a) polyether polyols,

[0054] (b) isocyanate, and

[0055] (c) optionally a chain extender.

[0056] In yet another embodiment, the TPU in Example 1 is obtained by reacting:

[0057] (a) polyether polyols having an average functionality of between 1.9 and 2.1 and a hydroxyl number of between 10 mg KOH / g and 500 mg KOH / g,

[0058] (b) isocyanate, and

[0059] (c) optionally a chain extender.

[0060] Suitable polyether polyols can be obtained from one or more alkylene oxides having 2 to 4 carbon atoms in the alkylene moiety by known methods, for example by anionic polymerization using alkali metal hydroxides, such as sodium hydroxide or potassium hydroxide, or alkali metal alkoxides, such as sodium methoxide, sodium ethoxide, potassium ethoxide or potassium isopropoxide as catalysts and by adding at least one amine-containing starter molecule, or by cationic polymerization using Lewis acids, such as antimony pentachloride, boron trifluoride etherate, etc., or bleaching earth as catalysts.

[0061] The starter molecules are generally selected such that their average functionality is between 2.0 and 8.0 or between 3.0 and 8.0. Optionally, mixtures of suitable starter molecules are used.

[0062] The starting molecules used for the polyether polyols include amine-containing starting molecules and hydroxyl-containing starting molecules. Suitable amine-containing starting molecules include, for example, aliphatic and aromatic diamines, such as ethylenediamine, propylenediamine, butylenediamine, hexamethylenediamine, phenylenediamine, toluenediamine, diaminodiphenylmethane, and isomers thereof.

[0063] Other suitable starter molecules further include alkanolamines, such as ethanolamine, N-methylethanolamine and N-ethylethanolamine, dialkanolamines, such as diethanolamine, N-methyldiethanolamine and N-ethyldiethanolamine, and trialkanolamines, such as triethanolamine and ammonia.

[0064] In one embodiment, the amine-containing starter molecule is selected from ethylenediamine, phenylenediamine, toluenediamine, and isomers thereof. In other embodiments, the amine-containing starter molecule comprises ethylenediamine.

[0065] The hydroxyl-containing starter molecule is selected from sugars, sugar alcohols, such as glucose, mannitol, sucrose, pentaerythritol, sorbitol; polyphenols, resols, such as oligomeric condensation products formed from phenol and formaldehyde, trimethylolpropane, glycerol, glycols, such as ethylene glycol, propylene glycol and condensation products thereof, such as polyethylene glycol and polypropylene glycol, such as diethylene glycol, triethylene glycol, dipropylene glycol, and water or a combination thereof.

[0066] In one embodiment, the hydroxyl-containing starter molecule comprises sugars and sugar alcohols, such as sucrose, sorbitol, glycerol, pentaerythritol, trimethylolpropane, and mixtures thereof. In other embodiments, the hydroxyl-containing starter molecule comprises sucrose, glycerol, pentaerythritol, and trimethylolpropane.

[0067] Suitable alkylene oxides having 2 to 4 carbon atoms are, for example, ethylene oxide, propylene oxide, tetrahydrofuran, 1,2-butylene oxide, 2,3-butylene oxide, and styrene oxide. The alkylene oxides can be used alone, in alternating successive applications, or as a mixture. In one embodiment, the alkylene oxide is propylene oxide and / or ethylene oxide. In other embodiments, the alkylene oxide is a mixture of ethylene oxide and propylene oxide, the mixture containing more than 50% by weight of propylene oxide.

[0068] In one embodiment, suitable polyether polyols are derived from tetrahydrofuran. Tetrahydrofuran is a cyclic ether and is converted to a linear polymer known as poly(tetramethylene ether) glycol (PTMEG) before obtaining TPU. Polyether polyols sold under the trade name Polytetrahydrofuran commercially available from BASF.

[0069] Therefore, in one embodiment, the TPU in Example 1 is obtained by reacting:

[0070] (a) polytetrahydrofuran having a hydroxyl number between 10 mg KOH / g and 500 mg KOH / g,

[0071] (b) isocyanate, and

[0072] (c) optionally a chain extender.

[0073] In one embodiment, the hydroxyl number of the polytetrahydrofuran is between 10 mg KOH / g and 400 mg KOH / g, or between 30 mg KOH / g and 300 mg KOH / g, or between 30 mg KOH / g and 200 mg KOH / g. In another embodiment, it is between 50 mg KOH / g and 200 mg KOH / g, or between 50 mg KOH / g and 150 mg KOH / g, 80 mg KOH / g and 150 mg KOH / g, or between 80 mg KOH / g and 130 mg KOH / g, or between 90 mg KOH / g and 130 mg KOH / g.

[0074] The suitable amount of polyether polyol is between 1 wt% and 99 wt% based on the total weight of TPU.

[0075] Suitable polyester polyols have an average functionality between 1.9 and 6.0, or between 1.9 and 5.0, or between 1.9 and 4.0, and a hydroxyl number between 10 mg KOH / g and 500 mg KOH / g.

[0076] The polyester polyols according to the present invention are based on the reaction products of carboxylic acids or anhydrides with hydroxyl-containing compounds. Suitable carboxylic acids or anhydrides have 2 to 20 carbon atoms or 4 to 18 carbon atoms, for example succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, oleic acid, phthalic anhydride. In particular, phthalic acid, isophthalic acid, terephthalic acid, oleic acid and phthalic anhydride or combinations thereof are included.

[0077] Suitable hydroxyl-containing compounds are selected from the group consisting of ethanol, ethylene glycol, propane-1,2-diol, propane-1,3-diol, butane-1,4-diol, butane-2,3-diol, hexane-1,6-diol, octan-1,8-diol, neopentyl glycol, cyclohexanedimethanol (1,4-bishydroxy-methylcyclohexane), 2-methyl-propane-1,3-diol, glycerol, trimethylolpropane, hexane-1,2,6-triol, butane-1,2,4-triol, trimethylolethane, pentaerythritol, p-cyclohexanediol, mannitol, sorbitol, methyl glycoside, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, polyethylene-propylene glycol, dibutylene glycol and polybutylene glycol. In one embodiment, the hydroxyl group-containing compound is selected from ethylene glycol, propylene-1,2-diol, propylene-1,3-diol, butane-1,4-diol, butane-2,3-diol, hexane-1,6-diol, octan-1,8-diol, neopentyl glycol, cyclohexanedimethanol (1,4-bis-hydroxy-methylcyclohexane), 2-methyl-propane-1,3-diol, glycerol, trimethylolpropane, hexane-1,2,6-triol, butane-1,2,4-triol, trimethylolethane, pentaerythritol, p-cyclohexanol, mannitol, sorbitol, methyl glycoside and diethylene glycol. In some embodiments, the compound containing a hydroxyl group is selected from ethylene glycol, propylene glycol, propylene glycol, butane glycol, butane glycol, hexane glycol, octan-1,8-diol, neopentyl glycol, and diethylene glycol. In other embodiments, the compound containing a hydroxyl group is selected from hexane glycol, neopentyl glycol, and diethylene glycol.

[0078] Suitable polyether-ester polyols have a hydroxyl number between 10 mg KOH / g and 500 mg KOH / g and an average functionality between 1.9 and 5.0.

[0079] Such polyether-ester polyols are obtainable as the reaction product of: i) at least one hydroxyl-containing starter molecule; ii) one or more fatty acids, fatty acid monoesters or mixtures thereof; and iii) one or more alkylene oxides having 2 to 4 carbon atoms.

[0080] The starter molecules of component i) are generally selected such that the average functionality of component i) is between 1.9 and 5.0. Optionally, mixtures of suitable starter molecules can be used.

[0081] In one embodiment, the hydroxyl-containing starter molecule of component i) is selected from sugars, sugar alcohols (glucose, mannitol, sucrose, pentaerythritol, sorbitol), polyphenols, resols, such as oligomeric condensates formed from phenol and formaldehyde, trimethylolpropane, glycerol, glycols such as ethylene glycol, propylene glycol and their condensates such as polyethylene glycols and polypropylene glycols, for example diethylene glycol, triethylene glycol, dipropylene glycol, water and mixtures thereof.

[0082] In other embodiments, the hydroxyl-containing starter molecule of component i) is selected from sugars and sugar alcohols such as sucrose and sorbitol, glycerol, and mixtures of said sugars and / or sugar alcohols with glycerol, water and / or glycols such as diethylene glycol and / or dipropylene glycol.

[0083] Described fatty acid or fatty acid monoester ii) be selected from polyhydroxy fatty acid, ricinoleic acid, hydroxy modified oil, hydroxy modified fatty acid and based on the fatty acid ester of nutmeg, palmitoleic acid, oleic acid, stearic acid, palmitic acid, vaccenic acid, petroselinic acid, gadoleic acid, erucic acid, nervonic acid, linoleic acid, α-and g-linolenic acid, stearidonic acid, arachidonic acid, eicosapentaenoic acid, docosapentaenoic acid, docosahexaenoic acid and composition thereof.Fatty acid can be used as pure fatty acid.In this respect, preferably use fatty acid methyl ester, as biodiesel or methyl oleate.

[0084] Biodiesel is understood to be fatty acid methyl esters within the meaning of the EN 14214 standard of 2010. The main components of biodiesel are usually produced from rapeseed oil, soybean oil or palm oil, which are mainly saturated C 16 to C 18 Methyl esters of fatty acids and mono- or polyunsaturated C 18 Methyl esters of fatty acids such as oleic acid, linoleic acid, and linolenic acid.

[0085] Suitable alkylene oxides iii) having 2 to 4 carbon atoms are, for example, ethylene oxide, propylene oxide, tetrahydrofuran, 1,2-butylene oxide, 2,3-butylene oxide and / or styrene oxide. The alkylene oxides can be used individually, in alternating succession or as a mixture.

[0086] In one embodiment, the alkylene oxide comprises propylene oxide and / or ethylene oxide. In other embodiments, the alkylene oxide is a mixture of ethylene oxide and propylene oxide, the mixture comprising more than 50 wt.% propylene oxide. In another embodiment, the alkylene oxide comprises only propylene oxide.

[0087] In another embodiment, suitable chain extenders are selected from alkanolamines, diols, and / or triols having a molecular weight between 49 g / mol and 499 g / mol. Suitable amounts of these chain extenders are known to those skilled in the art. For example, the chain extender may be present in an amount of up to 99 wt% or up to 20 wt%, based on the total weight of the TPU.

[0088] In one embodiment, suitable chain extenders can be selected from ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-butanediol, 1,5-pentanediol, methylpentanediol, 1,6-hexanediol, neopentyl glycol, trimethylolpropane, glycerol, pentaerythritol, diglycerol, glucose, 1,4:3,6 dianhydrohexitol, hydroquinone bis-2-hydroxyethyl ether and bis-2 (hydroxyethyl) -terephthalate. In another embodiment, it can be selected from triethylene glycol, propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-butanediol, 1,5-pentanediol, methylpentanediol and 1,6-hexanediol. In yet another embodiment, it can be selected from triethylene glycol, propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and 1,4-butanediol.In yet another embodiment, the chain extender comprises 1,4-butanediol.

[0089] Therefore, in one embodiment, the TPU in Example 1 is obtained by reacting:

[0090] (a) polytetrahydrofuran having a hydroxyl number between 10 mg KOH / g and 500 mg KOH / g,

[0091] (b) isocyanate, and

[0092] (c) a chain extender having a molecular weight between 49 g / mol and 499 g / mol.

[0093] In another embodiment, the TPU in Example 1 is obtained by reacting:

[0094] (a) polytetrahydrofuran having a hydroxyl number between 10 mg KOH / g and 500 mg KOH / g,

[0095] (b) isocyanate, and

[0096] (c) 1,4-Butanediol.

[0097] Suitable isocyanates for use in the present invention include aliphatic isocyanates or aromatic isocyanates. It should be understood that isocyanates include aliphatic isocyanates and aromatic isocyanates in monomeric and polymeric forms. The term "polymeric" refers to a polymeric grade of aliphatic and / or aromatic isocyanates that is independent of each other and includes different oligomers and homologues.

[0098] In one embodiment, the aliphatic isocyanate is selected from 1,4-tetramethylene diisocyanate, 1,5-pentamethylene diisocyanate, 1,6-hexamethylene diisocyanate, decamethylenyl diisocyanate, 1,12-dodecane diisocyanate, 2,2,4-trimethyl-hexamethylene diisocyanate, 2,4,4-trimethyl-hexamethylene diisocyanate, 2-methyl-1,5-pentamethylene diisocyanate, cyclobutane-1,3-diisocyanate, 1,2-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate. and 1,4-cyclohexane diisocyanate, 2,4-methylcyclohexane diisocyanate, 2,6-methylcyclohexane diisocyanate, 4,4′-dicyclohexyl diisocyanate, 2,4′-dicyclohexyl diisocyanate, 1,3,5-cyclohexane triisocyanate, isocyanatomethylcyclohexane isocyanate, isocyanatoethylcyclohexane isocyanate, bis(isocyanatomethyl)-cyclohexane diisocyanate, 4,4′-diisocyanatodicyclohexylmethane, 1,5-pentamethylene diisocyanate, isophorone diisocyanate, and mixtures thereof.

[0099] In one embodiment, aromatic isocyanate is used to obtain the TPU in Example 1. Suitable aromatic isocyanates are selected from toluene diisocyanate; polymeric toluene diisocyanate, methylene diphenyl diisocyanate and / or polymeric methylene diphenyl diisocyanate; m-phenylene diisocyanate; 1,5-naphthalene diisocyanate; 4-chloro-1; 3-phenylene diisocyanate; 2,4,6-tolyl triisocyanate, 1,3-diisopropylphenylene-2,4-diisocyanate; 1-methyl-3,5-diethylphenylene-2,4-diisocyanate; 1,3,5-triethylphenylene-2,4-diisocyanate; 1,3,5-triisopropyl-phenylene-2,4-diisocyanate. Isocyanates; 3,3'-diethyl-diphenyl-4,4'-diisocyanate; 3,5,3',5'-tetraethyl-diphenylmethane-4,4'-diisocyanate; 3,5,3',5'-tetraisopropyldiphenylmethane-4,4'-diisocyanate; 1-ethyl-4-ethoxy-phenyl-2,5-diisocyanate; 1,3,5-triethylbenzene-2,4,6-triisocyanate; 1-ethyl-3,5-diisopropylbenzene-2,4,6-triisocyanate, toluidine diisocyanate, and 1,3,5-triisopropylbenzene-2,4,6-triisocyanate.

[0100] In another embodiment, the aromatic isocyanate is selected from toluene diisocyanate; polymerized toluene diisocyanate, methylene diphenyl diisocyanate and / or polymerized methylene diphenyl diisocyanate; m-phenylene diisocyanate; 1,5-naphthalene diisocyanate; 4-chloro-1,3-phenylene diisocyanate; 2,4,6-tolyl triisocyanate, 1,3-diisopropylphenylene-2,4-diisocyanate; 1-methyl-3,5-diethylphenylene-2,4-diisocyanate. In yet another embodiment, the aromatic isocyanate comprises toluene diisocyanate; polymerized toluene diisocyanate, methylene diphenyl diisocyanate and / or polymerized methylene diphenyl diisocyanate; m-phenylene diisocyanate; 1,5-naphthalene diisocyanate; 4-chloro-1,3-phenylene diisocyanate. In yet other embodiments, the aromatic isocyanate is selected from toluene diisocyanate; polymeric toluene diisocyanate, methylene diphenyl diisocyanate and / or polymeric methylene diphenyl diisocyanate; m-phenylene diisocyanate. In further embodiments, the isocyanate comprises methylene diphenyl diisocyanate and / or polymeric methylene diphenyl diisocyanate.

[0101] Methylene diphenyl diisocyanate is available in three different isomeric forms: 2,2'-methylene diphenyl diisocyanate (2,2'-MDI), 2,4'-methylene diphenyl diisocyanate (2,4'-MDI), and 4,4'-methylene diphenyl diisocyanate (4,4'-MDI). Methylene diphenyl diisocyanate can be classified as monomeric methylene diphenyl diisocyanate and polymeric methylene diphenyl diisocyanate, known as industrial methylene diphenyl diisocyanate. Polymeric methylene diphenyl diisocyanate includes oligomeric species and methylene diphenyl diisocyanate isomers. Thus, polymeric methylene diphenyl diisocyanate can contain a single methylene diphenyl diisocyanate isomer or an isomeric mixture of two or three methylene diphenyl diisocyanate isomers, with the remainder being oligomeric species. Polymeric methylene diphenyl diisocyanate often has an isocyanate functionality greater than 2.0. In these products, the isomer ratios and the amount of oligomeric species can vary widely. For example, polymeric methylene diphenyl diisocyanate can typically contain 30 to 80 wt.% of methylene diphenyl diisocyanate isomers, with the remainder being the oligomeric species. Methylene diphenyl diisocyanate isomers are typically a mixture of 4,4'-methylene diphenyl diisocyanate, 2,4'-methylene diphenyl diisocyanate, and very low levels of 2,2'-methylene diphenyl diisocyanate.

[0102] In another embodiment, reaction products of isocyanates with polyols and mixtures of such reaction products with other diisocyanates and polyisocyanates may also be used.

[0103] In yet another embodiment, the isocyanate comprises polymeric methylene diphenyl diisocyanate as described above. Available from BASF as, but not limited to, Isocyanates commercially available under the trade name CYANOX® can also be used for the purposes of the present invention.

[0104] Suitable amounts of isocyanate provide an isocyanate index between 70 and 350, or between 80 and 300. In one embodiment, the isocyanate index is between 80 and 200, or between 80 and 150, or between 90 and 140. In another embodiment, the isocyanate index is between 90 and 130, or between 90 and 120, or between 90 and 110. The isocyanate index describes the molar ratio of NCO groups to isocyanate-reactive groups (polyol and chain extender). An index of 100 refers to a ratio of 1:1.

[0105] Therefore, in one embodiment, the TPU in Example 1 is obtained by reacting:

[0106] (a) polytetrahydrofuran having a hydroxyl number between 10 mg KOH / g and 500 mg KOH / g,

[0107] (b) aromatic isocyanates, and

[0108] (c) a chain extender having a molecular weight between 49 g / mol and 499 g / mol.

[0109] In another embodiment, the TPU in Example 1 is obtained by reacting:

[0110] (a) polytetrahydrofuran having a hydroxyl number between 10 mg KOH / g and 500 mg KOH / g,

[0111] (b) methylene diphenyl diisocyanate and / or polymeric methylene diphenyl diisocyanate, and

[0112] (c) a chain extender having a molecular weight between 49 g / mol and 499 g / mol.

[0113] In yet another embodiment, the TPU in Example 1 is obtained by reacting:

[0114] (a) polytetrahydrofuran having a hydroxyl number between 10 mg KOH / g and 500 mg KOH / g,

[0115] (b) methylene diphenyl diisocyanate and / or polymeric methylene diphenyl diisocyanate, and

[0116] (c) 1,4-Butanediol.

[0117] In one embodiment, the TPU further comprises a reinforcing agent. For the purposes of the present invention, the reinforcing agent is selected from the group consisting of metal fibers, metalized inorganic fibers, metalized synthetic fibers, glass fibers, polyester fibers, polyamide fibers, polyvinyl alcohol fibers, aramid fibers, graphite fibers, carbon fibers, ceramic fibers, mineral fibers, basalt fibers, inorganic fibers, aramid fibers, kenaf fibers, jute fibers, flax fibers, hemp fibers, cellulose fibers, sisal fibers, and coconut shell fibers.

[0118] In one embodiment, the reinforcing agent can be obtained in any shape and size. In another embodiment, the reinforcing agent is subjected to a surface treatment agent. The surface treatment agent is also called a sizing agent. The reinforcing agent further improves the mechanical properties of the TPU when subjected to the surface treatment agent. Generally, the sizing agent provides adhesion between the reinforcing agent and the TPU.

[0119] In one embodiment, the surface treatment agent is a coupling agent, and is selected from the group consisting of a silane coupling agent, a titanium coupling agent, and an aluminate coupling agent.

[0120] In one embodiment, the coupling agent comprises a silane coupling agent. Suitable silane coupling agents are selected from aminosilane, epoxysilane, methyltrimethoxysilane, methyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltriacetoxysilane and vinyltrimethoxysilane.

[0121] Suitable amounts of reinforcing agent in TPU are well known to those skilled in the art. In one embodiment, as described herein, the amount of reinforcing agent is such that the weight ratio between reinforcing agent and TPU is between 0.01:1.0 and 1.0:1.0.

[0122] In yet another embodiment, TPU can be obtained in the presence of a catalyst and / or additive. Suitable catalysts are well known to those skilled in the art. For example, tertiary amines and phosphine compounds, metal catalysts such as various metal chelates, acidic metal salts of strong acids, strong bases, alcoholates and phenates of various metals, salts of organic acids with various metals, organometallic derivatives of tetravalent tin, trivalent and pentavalent arsenic, sibium, and bismuth, and metal carbonyl compounds of iron and cobalt, and mixtures thereof, can be used as catalysts.

[0123] In one embodiment, tertiary amines include, but are not limited to, triethylamine, tributylamine, N-methylmorpholine, N-ethylmorpholine, N,N,N',N'-tetramethylethylenediamine, pentamethyl-diethylenetriamine and higher homologues (as described, for example, in DE-A 2,624,527 and 2,624,528), 1,4-diazabicyclo(2.2.2)octane, N-methyl-N'-dimethyl-aminoethylpiperazine, bis-(dimethylaminoalkyl)piperazine, Tris(dimethylaminopropyl)hexahydro-1,3,5-triazine, N,N-dimethylbenzylamine, N,N-dimethylcyclohexylamine, N,N-diethyl-benzylamine, bis-(N,N-diethylaminoethyl)adipic acid, N,N,N',N'-tetramethyl-1,3-butanediamine, N,N-dimethyl-p-phenylethylamine, 1,2-dimethylimidazole, 2-methylimidazole, monocyclic and bicyclic amines, and bis-(dialkylamino)alkyl ethers, such as 2,2-bis-(dimethylaminoethyl) ether. Triazine compounds such as, but not limited to, tris(dimethylaminopropyl)hexahydro-1,3,5-triazine may also be used.

[0124] In other embodiments, the metal catalyst comprises, for example, but not limited to, metal salts and organometallic compounds including tin, titanium, zirconium, hafnium, bismuth, zinc, aluminum, and iron compounds, such as tin organic compounds, preferably alkyl tins, such as dimethyl tin or diethyl tin, or tin organic compounds based on aliphatic carboxylic acids, preferably tin diacetate, tin dilaurate, dibutyltin diacetate, dibutyltin dilaurate, bismuth compounds, such as alkyl bismuths or related compounds, or iron compounds, preferably iron (II) acetylacetonate, or metal salts of carboxylic acids, such as tin-II isooctanoate, tin dioctoate, titanates, or bismuth-(III) neodecanoate, or combinations thereof.

[0125] As described above, the catalyst may be present in an amount up to 20 wt %, based on the total weight of the TPU.

[0126] In another embodiment, the additive is selected from alkylene carbonate, carbonamide, pyrrolidone, filler, flame retardant, dye, pigment, IR absorbing material, UV stabilizer, plasticizer, antistatic agent, fungicide, hydrolysis control agent, antioxidant, cell regulator and its mixture. Further details about additives can be found in, for example, Szycher's "Handbook of Polyurethanes", 2nd edition, 2013. Suitable amounts of these additives are well known to those skilled in the art. However, for example, the additive can be present in an amount of up to 20 wt% based on the total weight of the TPU.

[0127] Jounce Bumpers (20)

[0128] like Figure 1As shown, a dual-rate jounce bumper (20) limits jounce travel between a first component (22) and a second component (24) of a vehicle (26), wherein the second component (24) is spaced apart from the first component (22) and is movable toward the first component (22) along a jounce axis. For example, the dual-rate jounce bumper (20) can be used with a suspension system (28) of a vehicle (26) to limit movement of the suspension system (28) toward a frame member (30) of the vehicle (26). In such examples, limiting jounce between the suspension system (28) of the vehicle (26) and the frame member (30) limits and / or prevents impact forces experienced by the suspension system (28), such as when the vehicle (26) rides over a bump, from being transferred to the frame member (30). In other words, the dual-rate jounce bumper (20) provides cushioning between the suspension system (28) and the frame member (30) of the vehicle (26) by gradually stiffening the suspension system (28) as the suspension system (28) approaches the end of its maximum jounce travel, i.e., before elements of the suspension system (28) contact the frame member (30) of the vehicle (26).

[0129] In one embodiment, the dual-rate jounce bumper (20) of Example 1 is aligned with the jounce axis JA to ensure that as the second component (24) moves toward the first component (22), the second component (24) contacts the dual-rate jounce bumper (20) to limit jounce. When the second component (24) is a suspension system (28) of a vehicle (26), the dual-rate jounce bumper (20) is positioned between components of the suspension system (28), such as a strut assembly (32), and a frame member (30) of the vehicle (26), thereby decoupling the components of the suspension system (28) from the frame member (30). By decoupling the components of the suspension system (28) and the frame member (30), the dual-rate jounce bumper (20) prevents components of the suspension system (28) from directly impacting the frame member (30) as the suspension system (28) absorbs energy generated by an impact force.

[0130] In one embodiment, the second component (24) of Example 1 is a strut assembly (32) comprising a cylinder (34) and a piston rod (36) movable relative to the cylinder (34) along a jounce axis JA. The distal end (38) of the piston rod (36) is coupled to the first component (22), in this case a frame member (30), for coupling the suspension system (28) to the frame member (30) of the vehicle (26). It should be understood that the dual-rate jounce bumper (20) can be positioned between any elements of the vehicle (26).

[0131] In another embodiment, the bumper (40) of Example 1 has a cylindrical configuration. However, it should be understood that the bumper (40) can have any suitable configuration. The diameter D of the bumper (40) can vary along the length L of the bumper (40).

[0132] In another embodiment, the buffer (40) of embodiment 1 has a first end (42) and a second end (44) spaced apart from the first end (42). This is shown in Figure 3 In one embodiment, the first end (42) of the bumper (40) is coupled to the first component (22), wherein the second end (44) contacts the second component (24) as the second component (24) moves along the pitch axis JA toward the first component (22). However, it should be understood that the first end (42) of the bumper (40) can be coupled to the second component (24) such that the bumper (40) moves along the pitch axis JA with the second component (24). In such embodiments, the second end (44) of the bumper (40) will contact the first component (22).

[0133] In another embodiment, due to a force applied to the second component (24), the second component (24) moves toward the first component (22). A buffer (40) is disposed between the first component (22) and the second component (24) to limit the pitching of the second component (24) along the pitch axis JA due to the force applied to the second component (24). In other words, the buffer (40) prevents direct contact between the first component (22) and the second component (24).

[0134] In yet another embodiment, the buffer (40) in embodiment 1 may be made of a material having elasticity. Such elastic materials can bounce back to their original shape after being compressed. Suitable examples of such materials include, but are not limited to, microporous polyurethane, rubber, and mixtures thereof.

[0135] In another embodiment, as the bumper (40) of embodiment 1 is compressed, movement of the second component (24) along the pitch axis JA is prevented, which limits pitch. In addition, the compression of the bumper (40) absorbs some, if not all, of the energy applied to the second component (24), thereby preventing the second component (24) from contacting the first component (22). The bumper (40) attenuates the force acting on the second component (24) until the bumper (40) reaches maximum compression. Once the bumper (40) reaches maximum compression, the remaining force is transferred to the first component (22).

[0136] In yet another embodiment, the bumper (40) of embodiment 1 has at least one groove (46) for controlling the movement of the bumper (40) as the bumper (40) is compressed. This is shown in Figure 2The groove (46) can reduce the stiffness of the bumper (40) at the location of the groove (46) to control the compression of the bumper (40). In addition, the groove (46) allows the bumper (40) to be compressed along the pitch axis JA. In one embodiment, the groove (46) allows the bumper (40) of Example 1 to be compressed uniformly along the pitch axis JA. In another embodiment, the groove (46) minimizes lateral expansion of the bumper (40) when the bumper (40) is compressed.

[0137] In another embodiment, the buffer (40) in embodiment 1 has a plurality of protrusions (54). This is shown in Figure 4 and 5 In one embodiment, a plurality of protrusions (54) are present at equal intervals around the circumference of the buffer (40). The protrusions (54) may be carved at appropriate locations around the circumference of the buffer (40), for example, just below the first end (42) of the buffer (40). These protrusions (54) provide a mechanism for air to escape when the buffer (40) is compressed. Even if the piston rod (36) articulates and the size of the buffer (40) changes, the protrusions (54) on the outside of the buffer (40) provide continuous contact with the buffer cup (not shown).

[0138] While the present invention describes the presence of at least one groove (46) or a plurality of protrusions (54) on the bumper (40), it should be understood that other surface modifications are possible as contemplated by those skilled in the art.

[0139] In another embodiment, the first component (22) is a frame member (30) of a vehicle (26), and the second component (24) is a suspension system (28) of the vehicle (26) of Example 1. In such an embodiment, the dual-rate jounce bumper (20) is coupled to the frame member (30) such that the dual-rate jounce bumper (20) remains stationary and the cylinder (34) moves into contact with the dual-rate jounce bumper (20).

[0140] In another embodiment, the dual-rate jounce bumper (20) of embodiment 1 is coupled to a cylinder (34) of a strut assembly (32) such that the dual-rate jounce bumper (20) moves with the cylinder (34).

[0141] In one embodiment, the force generated on the second component (24) is an impact force generated in the suspension system (28) as the vehicle (26) passes over a bump. If the impact force is greater than the damping of the suspension system (28), then a component of the suspension system (28), such as the strut assembly (32), contacts and compresses the bumper (40). In such an embodiment, the bumper (40) may define a clearance hole (48) for receiving a piston rod (36) of the strut assembly (32), such that the piston rod (36) is positioned through the bumper (40) to position the bumper (40) between the cylinder (34) of the strut assembly (32) and the frame member (30) of the vehicle (26). Therefore, as the piston rod (36) retracts into the cylinder (34), the cylinder (34) of the strut assembly (32) will contact the bumper (40), thereby reducing the force acting on the strut assembly (32).

[0142] In one embodiment, an outer member (50) is positioned around the bumper (40) and is capable of limiting radial expansion of the bumper (40) as the bumper (40) is compressed to increase the stiffness of the bumper (40). The outer member (50) is obtained by overmolding stainless steel with TPU having a Shore D hardness ranging from 50 Shore D hardness to 80 Shore D hardness as measured according to ASTM D2240-15e1. It should be understood that the term "capable of limiting radial expansion" includes the ability of the outer member (50) to prevent radial expansion of the bumper (40). In other words, the outer member (50) of the bumper (40) does not expand radially at all.

[0143] In another embodiment, the outer member (50) of Example 1 has a hollow interior so that the bumper (40) is placed in the hollow interior. The outer member (50) can have any suitable configuration that can be placed around the bumper (40) so as to fit the bumper (40) completely or loosely. In another embodiment, the outer member (50) of Example 1 is fixed to the bumper (40) due to its configuration and has minimal movement in the axial direction. In other words, the outer member (50) has minimal movement or virtually no movement along the bump axis JA. In such embodiments, no additional means are required to fix the outer member (50) to the bumper (40).

[0144] Suitable configurations for the outer member (50) are known to those skilled in the art. However, in one embodiment, the outer member (50) of Example 1 has an annular configuration defining a hollow interior. The buffer (40) is disposed within the hollow interior of the outer member (50). It should be understood that the buffer (40) can be retained within the outer member (50) by any suitable means known to those skilled in the art.

[0145] As the bumper (40) is compressed, the bumper (40) expands radially. Eventually, the bumper (40) reaches maximum compression and therefore maximum radial expansion. The increased stiffness of the bumper (40) allows the dual-rate jounce bumper (20) to absorb more energy than a bumper with a lower stiffness.

[0146] In one embodiment, the bumper (40) of Example 1 is radially non-expandable relative to the bumper (40), thereby limiting or preventing radial expansion of the bumper (40). In another embodiment, the outer member (50) is radially expandable relative to the bumper (40) while still limiting radial expansion of the bumper (40). In this manner, the outer member (50) has a stiffness that is different from the stiffness of the bumper (40).

[0147] In one embodiment, the stiffness of the outer member (50) in Example 1 is greater than the stiffness of the buffer (40). Adjusting the stiffness of the outer member (50) controls the compression of the buffer (40). For example, the stiffness of the outer member (50) can be adjusted so that the buffer (40) can be compressed to a predetermined value by the second component (24) before the outer member (50) begins to expand radially. In other words, the radial expansion of the buffer (40) and the outer member (50) can be two-stage, so that the buffer (40) is first compressed and expanded, and then the outer member (50) expands. For example, as the buffer (40) is compressed, the buffer (40) radially expands into the outer member (50). The outer member (50) initially resists the radial expansion, which prevents the buffer (40) from expanding further. Then, as the force continues to act on the buffer (40), the outer member (50) begins to expand radially, and the buffer (40) continues to expand radially. The radial expansion of the outer member (50) allows the dual-stage, dual-rate jounce bumper (20) to absorb more energy.

[0148] In another embodiment, the outer member (50) in Example 1 comprises an upper surface (501), a lower surface (502), a first wall (503) and a second wall (504). This is shown in Figure 6 The upper surface (501), the lower surface (502), the first wall (503) and the second wall (504) are independent of each other and can be uniform or non-uniform. "Uniform surface" refers to a smooth surface, such as, but not limited to, a curved or flat surface. "Non-uniform" refers to a rough surface. In other words, a non-uniform surface is not a smooth surface and can have a variety of surface characteristics, such as, but not limited to, serrations, ridges, teeth, saw edges, teeth, Z-shaped, notched, and notched.

[0149] In another embodiment, each of the upper surface (501) and the lower surface (502) is a uniform surface. Specifically, the upper surface (501) and the lower surface (502) are arcuate surfaces. The arcuate surface controls the radial expansion of the outer member (50), thereby limiting the radial expansion of the buffer (40). "Arcuate surface" refers to a curved surface, such as a concave surface or a convex surface. In one embodiment, each of the upper surface (501) and the lower surface (502) is a concave surface, that is, the surface is curved inward. In another embodiment, the upper surface (501) is a concave surface, and the lower surface (502) is a flat surface.

[0150] In one embodiment, the upper surface (501) and the lower surface (502) are inclined toward each other. In another embodiment, when viewed along the coronal plane (BB), the upper surface (501), the first wall (503), the lower surface (502), and the second wall (504) are all connected to form a triangular cross-section. In such embodiments, the triangular cross-section is defined by a first side (505), a second side (506), and a third side (507). In one embodiment, the first side (505) is formed by the upper surface (501), specifically, a concave surface in the upper surface (501), as described herein. Similarly, the second side (506) is formed by the lower surface (502), specifically, a concave surface in the lower surface (502).

[0151] In one embodiment, the angle θ between the first side (505) and the second side (506) of the triangular cross section is subtended. This is shown in Figure 6b In another embodiment, the angle θ is between 30° and 90°. In yet another embodiment, it is between 40° and 90°, or 45° and 90°, or 50° and 90°. In another embodiment, it is between 55° and 90°, or 60° and 90°, or 65° and 90°. In another embodiment, it is between 70° and 90°, or 75° and 90°, or 75° and 85°. In yet another embodiment, the angle θ is 80°.

[0152] In another embodiment, the outer member (50) has a thickness defined by the relative positioning of the first wall (503) and the second wall (504). In other words, the thickness of the outer member (50) is defined by the spacing between the first wall (503) and the second wall (504). The thickness of the outer member (50) is determined based on several parameters, such as, but not limited to, the vehicle (26) category (e.g., truck, car, van, etc.), the load-bearing capacity, the thickness of the stainless steel, and the amount of TPU used for overmolding. A person skilled in the art can select a suitable thickness for the outer member (50), however, in one embodiment, the thickness of the outer member (50) in Example 1 is in the range of 1.0 to 10.0 mm. In another embodiment, it is between 2.0 mm and 10.0 mm, or 2.0 mm and 9.0 mm, or 3.0 mm and 9.0 mm. In yet another embodiment, it is between 3.0 mm and 9.5 mm, or 4.0 mm and 9.5 mm, or 5.0 mm and 9.5 mm.

[0153] In one embodiment, the stainless steel in Example 1 is a stainless steel ring (52). For example, the stainless steel ring (52) can be a vertical ring or a horizontal ring. A "vertical ring" refers to a stainless steel ring (52) whose height is greater than its thickness. A "horizontal ring" refers to a stainless steel ring (52) whose thickness is greater than its height. In one embodiment, the stainless steel in Example 1 is a vertical stainless steel ring (52). In another embodiment, the stainless steel in Example 1 is a horizontal stainless steel ring (52). The horizontal stainless steel ring is shown in FIG. Figure 3 and Figure 6b middle.

[0154] In another embodiment, the stainless steel ring (52) is not preferably of a circular cross-section, particularly for use in the outer member (50) of Example 1, because for a similarly sized triangular cross-section, this would result in an increased weight of the stainless steel ring (52), as described herein. This would be counterproductive to achieving the objectives of the present invention and, therefore, reduce the performance of the jounce bumper (20).

[0155] In one embodiment, the thickness of the stainless steel ring (52) in the outer member (50) in Example 1 ranges from 1.0 mm to 3.0 mm. In another embodiment, it ranges from 1.5 mm to 3.0 mm.

[0156] In another embodiment, the outer member (50) of Example 1 can be obtained by overmolding stainless steel with a plastic material other than TPU. Suitable plastic materials are known to those skilled in the art. However, in one embodiment, the plastic material can be selected from thermoplastic polymers such as, but not limited to, polypropylene, polyamide, polyphthalamide, polybutylene terephthalate, polyethylene, or mixtures thereof. In addition, these plastic materials can be reinforced with suitable reinforcing agents, as described herein.

[0157] In one embodiment, the overmolding in Example 1 is performed at a temperature in a range between 200°C and 240°C.

[0158] In another embodiment, the overmolding in Example 1 is injection overmolding. Suitable overmolding techniques for use with the present invention are well known to those skilled in the art. For example, overmolding can be performed by arranging a heated injection barrel with a screw that is arranged inside the barrel and connected to a hopper containing TPU pellets. The TPU is then fed into the injection barrel where it is heated and, by the action of the screw, injected through a nozzle in a molten state. In a further embodiment, a plastic material can be blended with the TPU and the pellets injected through a nozzle in a molten state. In one embodiment, the temperature of the injection barrel is between 210°C and 230°C, while the nozzle temperature is between 220°C and 240°C.

[0159] In another embodiment, the dual-rate jounce bumper (20) of Example 1 is connected to a strut assembly (32), and more specifically, to a cylinder (34) of the strut assembly (32) for connecting the dual-rate jounce bumper (20) to the strut assembly (32). Because the strut assembly (32) is coupled to the frame member (30), connecting the dual-rate jounce bumper (20) to the cylinder (34) of the strut assembly (32) also connects the dual-rate jounce bumper (20) to the vehicle (26). However, it should be understood that the dual-rate jounce bumper (20) can be connected to the frame member (30) for connecting the dual-rate jounce bumper (20) to the vehicle (26).

[0160] As described herein, the dual-rate jounce bumper (20) of Example 1 limits jounce travel of a vehicle (26) body, can carry loads up to 150 kN, minimizes NVH, prevents suspension overtravel, reduces weight, and is cost-effective. Specifically, these advantages are attributed to an outer member (50) disposed around the bumper (40) that is obtained by overmolding stainless steel with TPU having a Shore D hardness ranging from 50 Shore D hardness to 80 Shore D hardness.

[0161] Another aspect of the present invention is embodiment 2, which relates to a vehicle (26), wherein the vehicle (26) comprises:

[0162] a frame member (30) having a first portion (22),

[0163] a suspension having a second member (24), and

[0164] The dual-rate jounce buffer (20) of embodiment 1.

[0165] Yet another aspect of the present invention is Example 3, which relates to a ring obtained by overmolding stainless steel with TPU having a Shore D hardness ranging from 50 Shore D hardness to 80 Shore D hardness measured according to ASTM D2240-15e1, the ring comprising an upper surface, a lower surface, a first wall, and a second wall, wherein the upper surface and the lower surface are inclined toward each other, wherein each of the upper surface and the lower surface is an arcuate surface. This is shown in Figure 6 middle.

[0166] In this context, the TPU referred to herein is the same as the TPU described in Example 1 or 2. In one embodiment, the outer member (50) in Example 1 or 2 is the ring of Example 3.

[0167] In another embodiment, each of the upper and lower surfaces is a curved surface, as described herein. In one embodiment, each of the upper and lower surfaces of Example 3 is a concave surface, i.e., the surfaces are curved inwardly. In another embodiment, the upper surface is a concave surface, and the lower surface is a flat surface as in Example 3.

[0168] In another embodiment, when viewed along the coronal plane (BB), the upper surface, the first wall, the lower surface, and the second wall in Example 3 are all connected to form a triangular cross-section, such as Figure 6a and Figure 6b In such embodiments, the triangular cross-section is defined by a first side, a second side, and a third side. In one embodiment, the first side is formed by the upper surface, particularly a concave surface in the upper surface, as described herein. Similarly, the second side is formed by the lower surface, particularly a concave surface in the lower surface.

[0169] In another embodiment, the angle θ between the first side and the second side of the triangular cross-section is θ. In another embodiment, the angle θ is between 30° and 90°. In yet another embodiment, it is between 40° and 90°, or 45° and 90°, or 50° and 90°. In another embodiment, it is between 55° and 90°, or 60° and 90°, or 65° and 90°. In another embodiment, it is between 70° and 90°, or 75° and 90°, or 75° and 85°. In yet another embodiment, the angle θ is 80°.

[0170] In another embodiment, the ring has a thickness defined by the relative positioning of the first wall and the second wall. In other words, the thickness of the ring is defined by the spacing between the first wall and the second wall. A person skilled in the art can select an appropriate thickness based on the desired application of the ring; however, in one embodiment, the ring has a thickness ranging from 1.0 to 10.0 mm. In another embodiment, it is between 2.0 mm and 10.0 mm, or 2.0 mm and 9.0 mm, or 3.0 mm and 9.0 mm. In yet another embodiment, it is between 3.0 mm and 9.5 mm, or 4.0 mm and 9.5 mm, or 5.0 mm and 9.5 mm.

[0171] In one embodiment, the stainless steel in Example 3 is a stainless steel ring (52). For example, the stainless steel ring (52) can be a vertical ring or a horizontal ring. A "vertical ring" refers to a stainless steel ring (52) whose height is greater than its thickness. A "horizontal ring" refers to a stainless steel ring (52) whose thickness is greater than its height. In one embodiment, the stainless steel in Example 1 is a vertical stainless steel ring (52). In another embodiment, the stainless steel in Example 1 is a horizontal stainless steel ring (52).

[0172] In one embodiment, the thickness of the stainless steel ring (52) in the ring of Example 3 is in the range of 1.0 mm to 3.0 mm. In another embodiment, it is in the range of 1.5 mm to 3.0 mm.

[0173] In another embodiment, the ring of Example 3 may be obtained by overmolding stainless steel with a plastic material other than TPU, as described herein.

[0174] In one embodiment, the overmolding in Example 1 is performed at a temperature in a range between 200°C and 240°C.

[0175] In another embodiment, the overmolding in Example 3 is injection overmolding. Suitable overmolding techniques for use with the present invention are well known to those skilled in the art. For example, overmolding can be performed by arranging a heated injection barrel with a screw that is arranged inside the barrel and connected to a hopper containing TPU pellets. The TPU is then fed into the injection barrel where it is heated and, by the action of the screw, injected through a nozzle in a molten state. In a further embodiment, a plastic material can be blended with the TPU and the pellets injected through the nozzle in a molten state. In one embodiment, the temperature of the injection barrel is between 210°C and 230°C, while the nozzle temperature is between 220°C and 240°C.

[0176] Reference Signs List

[0177] 20 jounce bumpers 22 First component 24 Second component 26 vehicle 28 Suspension system 30 Frame components 32 Pillar assembly 34 Cylinder 36 piston rod 38 End 40 buffer 42 First end 44 The second end 46 groove 48 Clearance holes 50 External components 52 stainless steel ring 54 bulge 501 upper surface 502 lower surface 503 First wall 504 Second wall 505 First side 506 Second side 507 Third side

[0178] The invention is explained in more detail by the following embodiments and combinations of the embodiments resulting from the corresponding dependent references and connections:

[0179] I. A dual-rate jounce bumper (20) for limiting jounce travel between a first member (22) and a second member (24) of a vehicle (26), wherein the second member (24) is spaced from the first member (22) and movable toward the first member (22) along a jounce axis, the jounce bumper (20) comprising:

[0180] a bumper (40) having a first end (42) for coupling to the first component (22) and a second end (44) spaced from the first end (42) for contacting the second component (24), wherein the bumper (40) is compressible between the first component (22) and the second component (24) for limiting jolts, wherein the bumper (40) is radially expandable as the bumper (40) is compressed, and

[0181] an outer member (50) disposed about the bumper (40) and capable of limiting radial expansion of the bumper (40) as the bumper (40) is compressed to increase the stiffness of the bumper (40),

[0182] The outer member (50) is obtained by overmolding stainless steel with thermoplastic polyurethane having a Shore D hardness ranging from 50 Shore D hardness to 80 Shore D hardness measured according to ASTM D2240-15e1.

[0183] II. The dual-rate jounce bumper (20) of embodiment I, wherein the outer member (50) has a hollow interior such that the bumper (40) is seated within the hollow interior.

[0184] III. The dual-rate jounce bumper (20) of embodiment I or II, wherein the outer member (50) comprises an upper surface, a lower surface, a first wall, and a second wall.

[0185] IV. The dual-rate jounce bumper (20) of embodiment III, wherein the upper surface and the lower surface are inclined toward each other.

[0186] V. The dual-rate jounce bumper (20) of embodiment III or IV, wherein each of the upper surface and the lower surface is a curved surface.

[0187] VI. The dual-rate jounce bumper (20) of one or more of embodiments I to V, wherein the upper surface, the first wall, the lower surface, and the second wall are all connected to form a triangular cross-section when viewed along the frontal plane (BB).

[0188] VII. The dual rate jounce bumper (20) of embodiment VI, wherein the triangular cross-section is defined by a first side, a second side, and a third side, the first side and the second side forming an angle θ therebetween.

[0189] VIII. The dual-rate jounce bumper (20) of embodiment VII, wherein the angle θ is between 30° and 90°.

[0190] IX. The dual-rate jounce bumper (20) of embodiment VI or VII, wherein the angle θ is 80°.

[0191] X. The dual-rate jounce bumper (20) of one or more of embodiments III to IX, wherein the outer member (50) has a thickness defined by the relative positioning of the first wall and the second wall.

[0192] XI. The dual-rate jounce bumper (20) of embodiment X, wherein the outer member (50) has a thickness in the range of 1.0 mm to 10.0 mm.

[0193] XII. The dual-rate jounce bumper (20) of one or more of embodiments I to XI, wherein the stainless steel is a stainless steel ring (52).

[0194] XIII. The dual-rate jounce bumper (20) of embodiment XII, wherein the stainless steel ring (52) has a thickness in the range of 1.0 mm to 3.0 mm.

[0195] XIV. The dual-rate jounce bumper (20) of one or more of Examples I to XIII, wherein the thermoplastic polyurethane has a Shore D hardness in the range of 60 Shore D hardness to 80 Shore D hardness as determined according to ASTM D2240-15e1.

[0196] XV. The dual-rate jounce bumper (20) according to one or more of embodiments I to XIV, wherein the thermoplastic polyurethane is obtained by reacting:

[0197] (a) polyols,

[0198] (b) isocyanate, and

[0199] (c) optionally a chain extender.

[0200] XVI. The dual-rate jounce bumper (20) of embodiment XV, wherein the polyol is selected from the group consisting of polyether polyols, polyester polyols, polyether-ester polyols, and mixtures thereof.

[0201] XVII. The dual-rate jounce bumper (20) of embodiment XV or XVI, wherein the polyol comprises a polyether polyol.

[0202] XVIII. The dual-rate jounce bumper (20) of embodiment XVII, wherein the polyether polyol has an average functionality between 1.9 and 2.1 and a hydroxyl number between 10 mg KOH / g and 500 mg KOH / g.

[0203] XIX. The dual-rate jounce bumper (20) of one or more of embodiments XV to XVIII, wherein the isocyanate comprises an aliphatic isocyanate or an aromatic isocyanate.

[0204] XX. The dual-rate jounce bumper (20) of one or more of embodiments XV to XIX, wherein the isocyanate comprises an aromatic isocyanate.

[0205] XXI. A dual-rate jounce bumper (20) according to embodiment XIX or XX, wherein the aromatic isocyanate is selected from the group consisting of toluene diisocyanate; polymeric toluene diisocyanate, methylene diphenyl diisocyanate and / or polymeric methylene diphenyl diisocyanate; m-phenylene diisocyanate; 1,5-naphthalene diisocyanate; 4-chloro-1; 3-phenylene diisocyanate; 2,4,6-tolyl triisocyanate, 1,3-diisopropylphenylene-2,4-diisocyanate; 1-methyl-3,5-diethylphenylene-2,4-diisocyanate; 1,3,5-triethylphenylene-2,4-diisocyanate; 1,3, 5-Triisopropyl-phenylene-2,4-diisocyanate; 3,3'-diethyl-diphenyl-4,4'-diisocyanate; 3,5,3',5'-tetraethyl-diphenylmethane-4,4'-diisocyanate; 3,5,3',5'-tetraisopropyl-diphenylmethane-4,4'-diisocyanate; 1-ethyl-4-ethoxy-phenyl-2,5-diisocyanate; 1,3,5-triethylbenzene-2,4,6-triisocyanate; 1-ethyl-3,5-diisopropylbenzene-2,4,6-triisocyanate, tolidine diisocyanate, and 1,3,5-triisopropylbenzene-2,4,6-triisocyanate.

[0206] XXII. The dual-rate jounce bumper (20) of embodiment XX or XXI, wherein the aromatic isocyanate comprises methylene diphenyl diisocyanate and / or polymeric methylene diphenyl diisocyanate.

[0207] XXIII. The dual-rate jounce bumper (20) of one or more of embodiments XV to XXII, wherein the chain extender has a molecular weight of ≥49 g / mol to ≤499 g / mol.

[0208] XXIV. The dual-rate jounce bumper (20) of one or more of embodiments XV to XXIII, wherein the chain extender is selected from the group consisting of ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-butanediol, 1,5-pentanediol, methylpentanediol, 1,6-hexanediol, neopentyl glycol, trimethylolpropane, glycerol, pentaerythritol, diglycerol, glucose, 1,4:3,6 dianhydrohexitol, hydroquinone bis-2-hydroxyethyl ether, and bis-2(hydroxyethyl)-terephthalate.

[0209] XXV. The dual-rate jounce bumper (20) of one or more of embodiments XV to XXIV, wherein the chain extender comprises 1,4-butanediol.

[0210] XXVI. The dual-rate jounce bumper (20) of one or more of embodiments I to XXV, wherein the dual-rate jounce bumper (20) is capable of carrying a load of at most 150 kN.

[0211] XXVII. A vehicle (26) comprising:

[0212] a frame member (30) having a first portion (22),

[0213] a suspension having a second member (24), and

[0214] A dual rate jounce bumper (20) according to one or more of embodiments I to XXVI.

[0215] XXVIII. A ring obtained by overmolding stainless steel with thermoplastic polyurethane having a Shore D hardness in the range of 50 Shore D hardness to 80 Shore D hardness as measured according to ASTM D2240-15e1, the ring comprising an upper surface, a lower surface, a first wall, and a second wall, wherein the upper surface and the lower surface are inclined toward each other, wherein each of the upper surface and the lower surface is an arcuate surface.

[0216] XXIX. The ring of embodiment XXVIII, wherein the upper surface, the first wall, the lower surface, and the second wall are all connected to form a triangular cross-section when viewed along the coronal plane (BB).

[0217] XXX. The ring of embodiment XXIX, wherein the triangular cross-section is defined by a first side, a second side, and a third side, the first side and the second side forming an angle θ therebetween.

[0218] XXXI. The ring of embodiment XXX, wherein the angle θ is between 30° and 90°.

[0219] XXXII. The ring of embodiment XXX or XXXI, wherein the angle θ is 80°.

[0220] XXXIII. The ring of one or more of embodiments XVIII to XXXII, wherein the thickness is defined by the relative positioning of the first wall and the second wall.

[0221] XXXIV. The ring of one or more of embodiments XVIII to XXXIII, wherein the stainless steel is a stainless steel ring (52).

[0222] XXXV. The ring of embodiment XXXIV, wherein the stainless steel ring (52) has a thickness in the range of 1.0 mm to 3.0 mm.

[0223] XXXVI. The ring of one or more of embodiments XVIII to XXV, wherein the thermoplastic polyurethane has a Shore D hardness in the range of 60 Shore D hardness to 80 Shore D hardness as determined according to ASTM D2240-15e1.

Claims

1. A dual-rate jounce bumper (20) for limiting jounce travel between a first member (22) and a second member (24) of a vehicle (26), wherein the second member (24) is spaced from the first member (22) and is movable toward the first member (22) along a jounce axis, the jounce bumper (20) comprising: A buffer (40) having a first end (42) for coupling to the first component (22) and a second end (44) spaced from the first end (42) for contacting the second component (24), wherein the buffer (40) compressible between the first member (22) and the second member (24) for limiting jolts, wherein the bumper (40) is radially expandable as the bumper (40) is compressed, and an outer member (50) disposed about the bumper (40) and capable of limiting radial expansion of the bumper (40) as the bumper (40) is compressed to increase the stiffness of the bumper (40), wherein the outer member (50) is obtained by overmolding stainless steel with thermoplastic polyurethane having a Shore D hardness ranging from 60 Shore D hardness to 80 Shore D hardness as determined according to ASTM D2240-15e1, The thermoplastic polyurethane is obtained by reacting: polyol, isocyanate, and optionally a chain extender, wherein the polyol comprises a polyether polyol, wherein the average functionality of the polyether polyol is between 1.9 and 2.1, and the hydroxyl number thereof is between 10 mg KOH / g and 500 mg KOH / g, wherein the isocyanate comprises an aliphatic isocyanate or an aromatic isocyanate, The aromatic isocyanate comprises methylene diphenyl diisocyanate and / or polymeric methylene diphenyl diisocyanate.

2. The dual rate jounce bumper (20) of claim 1, wherein the outer member (50) has a hollow interior such that the bumper (40) is seated within the hollow interior.

3. The dual rate jounce bumper (20) of claim 1 or 2, wherein the outer member (50) comprises an upper surface, a lower surface, a first wall, and a second wall.

4. The dual rate jounce bumper (20) of claim 3, wherein the upper surface and the lower surface are inclined toward each other.

5. The dual-rate jounce bumper (20) of claim 3, wherein each of the upper surface and the lower surface is a curved surface.

6. The dual rate jounce bumper (20) of claim 3, wherein the upper surface, the first wall, the lower surface, and the second wall are all connected to form a triangular cross-section when viewed along a frontal plane (BB).

7. The dual rate jounce bumper (20) of claim 6, wherein the triangular cross-section is defined by a first side, a second side, and a third side, the first side and the second side forming an angle θ therebetween.

8. The dual rate jounce bumper (20) of claim 7, wherein the angle θ is between 30° and 90°.

9. The dual rate jounce bumper (20) of claim 1 or 2, wherein the stainless steel is a stainless steel ring (52).

10. The dual-rate jounce bumper (20) of claim 1, wherein the chain extender comprises 1,4-butanediol.

11. The dual-rate jounce bumper (20) according to claim 1 or 2, wherein the dual-rate jounce bumper (20) is capable of carrying a load of at most 150 kN.

12. A vehicle (26) comprising: a frame member (30) having a first portion (22), a suspension having a second member (24), and A dual rate jounce bumper (20) as claimed in any one of claims 1 to 11.

13. A ring obtained by overmolding stainless steel with thermoplastic polyurethane having a Shore D hardness ranging from 60 Shore D hardness to 80 Shore D hardness as measured according to ASTM D2240-15e1, the ring comprising an upper surface, a lower surface, a first wall, and a second wall, wherein the upper surface and the lower surface are inclined toward each other, wherein each of the upper surface and the lower surface is an arcuate surface, wherein the thermoplastic polyurethane is obtained by reacting: polyol, isocyanate, and optionally a chain extender, wherein the polyol comprises a polyether polyol, wherein the average functionality of the polyether polyol is between 1.9 and 2.1, and the hydroxyl number thereof is between 10 mg KOH / g and 500 mg KOH / g, wherein the isocyanate comprises an aliphatic isocyanate or an aromatic isocyanate, The aromatic isocyanate comprises methylene diphenyl diisocyanate and / or polymeric methylene diphenyl diisocyanate.

14. The ring of claim 13, wherein the upper surface, the first wall, the lower surface, and the second wall are all connected to form a triangular cross-section when viewed along the coronal plane (BB).

15. The ring of claim 14, wherein the triangular cross-section is defined by a first side, a second side, and a third side, the first side and the second side forming an angle θ therebetween. The ring of claim 15 , wherein the angle θ is between 30° and 90°.

17. The ring according to any one of claims 13 to 16, wherein the stainless steel is a stainless steel ring (52).

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