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Starley & Grout patents
Mark McMaster wrote in message ...
For well designed and constructed wheels, the spoke breakage rate should be minimal. The expectation should be that a wheel should be able to have several worn out rims replaced without a spoke breakage (several of the wheels I have built are on their second rims with all the original spokes). I tend to agree with this posting, but know your methods differ to mine. You do not mention wheel or rim stability, is it of no concern to you? James Starley illustrates his high wheeler with 40 spokes paired together at the rim. A safety bikes wheel is half this size so 20 spokes should be sufficient for a 27" rim. Due to non pairing I think 30% less ie 14 spokes may be sufficient. Extract from 3959 Starley patent of 1874 "...increase their stability & improve their speed. " He mentions strength, lightness and beauty of appearance. "The spokes are screwed up until the heads of the spokes bear lightly against the rim. This arrangement I follow for the spokes of both flanges, and I thus produce a crossing of the spokes which will posses an elegant appearance, while at the same time I secure great stiffness with the use of a light wire." Why should stability not be an issue 130 years later? The point was a light wheel could be constructed that was stable. His 'crossing of the spokes' was directed at the flange which was pierced with a drill'd and threaded pin into which a spoke came from opposing points of the wheel and not the interleave as used today. Grout's patent of 1876 introduces rolling bearings and places an adjusting nut at the rim. If someone could give other names and dates for relevant patents on wheels I could examine originals and report my findings. Trevor |
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Trevor wrote:
Mark McMaster wrote in message ... For well designed and constructed wheels, the spoke breakage rate should be minimal. The expectation should be that a wheel should be able to have several worn out rims replaced without a spoke breakage (several of the wheels I have built are on their second rims with all the original spokes). I tend to agree with this posting, but know your methods differ to mine. You do not mention wheel or rim stability, is it of no concern to you? James Starley illustrates his high wheeler with 40 spokes paired together at the rim. A safety bikes wheel is half this size so 20 spokes should be sufficient for a 27" rim. Due to non pairing I think 30% less ie 14 spokes may be sufficient. I think you are making a number of assumptions. Firstly, Starley's wire spoked wheels were an innovation to make an improvement on wooden compression spoked wheels, which are by their nature very heavy. In addition, since the single row of spokes in wooden compression spoke wheels have no bracing angle, the spokes must be very broad (and heavy) to achieve the desired lateral stiffness. Starley's spokes were at a fairly wide bracing angle, even for today's smaller wheels, so they were likely able to achieve the same (or greater) lateral stiffness at less weight. We also don't know the weight and stiffness of his rim, which are also important in achieve wheel strength and stiffness. There are a number of modern 700c wheels which have a reduced number of spokes - 20, 16, 14 or even 12 spokes. However, for these wheels to to adequately stiff and strong, they need a stiff and strong rim. Using a larger number of spokes allows one to use a much lighter rim, with the resulting wheel being both lighter overall (despite their greater number of spokes), and more reliable, for the same strength and stiffness. Extract from 3959 Starley patent of 1874 "...increase their stability & improve their speed. " He mentions strength, lightness and beauty of appearance. "The spokes are screwed up until the heads of the spokes bear lightly against the rim. This arrangement I follow for the spokes of both flanges, and I thus produce a crossing of the spokes which will posses an elegant appearance, while at the same time I secure great stiffness with the use of a light wire." Why should stability not be an issue 130 years later? The point was a light wheel could be constructed that was stable. His 'crossing of the spokes' was directed at the flange which was pierced with a drill'd and threaded pin into which a spoke came from opposing points of the wheel and not the interleave as used today. Here you are making your largest assumption - how do we know a patented idea really has all the benefits that are claimed? Patent examiners don't make quantitative analyses of claims, they simply verify the inventions are non-obviousness, unique and might have some utility. You should probably know that only a small fraction of inventions that are patented actually make it to market, most often because they are either impractical, or do not offer enough of an improvement over existing designs (if they offer any improvement at all). Not to mention the fact that patent examiners are not always as thorough as they could be, and patents are frequently discovered to be invalid in later investigation. For example, Rolf Deitrich managed to get issued a patent on pairing spokes in bicycle wheels, despite the fact that some of the first wire spoked wheels over 135 years ago had paired spokes! Another major assumption is that Starley had optimized his wheels on the first go-around 130 years ago. Since the actual mechanics of how loads are distributed (and how the stiffness of each component effects the load distribution) in tension spokes wheels were still not known until many years later, it is likely that Starley's wheels were not yet optimized, and were heavier than they needed to be to achieve the required strength and stiffness. Just how stiff and light were Starley's wheels? While some versions might have been as stiff as today's wheels, they were probably much, much heavier. If you are building your wheels based on a 125 year old patent, it is highly likely that your wheels are also far from optimized. Mark McMaster |
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Trevor wrote:
Mark McMaster wrote in message ... For well designed and constructed wheels, the spoke breakage rate should be minimal. The expectation should be that a wheel should be able to have several worn out rims replaced without a spoke breakage (several of the wheels I have built are on their second rims with all the original spokes). I tend to agree with this posting, but know your methods differ to mine. You do not mention wheel or rim stability, is it of no concern to you? James Starley illustrates his high wheeler with 40 spokes paired together at the rim. A safety bikes wheel is half this size so 20 spokes should be sufficient for a 27" rim. Due to non pairing I think 30% less ie 14 spokes may be sufficient. I think you are making a number of assumptions. Firstly, Starley's wire spoked wheels were an innovation to make an improvement on wooden compression spoked wheels, which are by their nature very heavy. In addition, since the single row of spokes in wooden compression spoke wheels have no bracing angle, the spokes must be very broad (and heavy) to achieve the desired lateral stiffness. Starley's spokes were at a fairly wide bracing angle, even for today's smaller wheels, so they were likely able to achieve the same (or greater) lateral stiffness at less weight. We also don't know the weight and stiffness of his rim, which are also important in achieve wheel strength and stiffness. There are a number of modern 700c wheels which have a reduced number of spokes - 20, 16, 14 or even 12 spokes. However, for these wheels to to adequately stiff and strong, they need a stiff and strong rim. Using a larger number of spokes allows one to use a much lighter rim, with the resulting wheel being both lighter overall (despite their greater number of spokes), and more reliable, for the same strength and stiffness. Extract from 3959 Starley patent of 1874 "...increase their stability & improve their speed. " He mentions strength, lightness and beauty of appearance. "The spokes are screwed up until the heads of the spokes bear lightly against the rim. This arrangement I follow for the spokes of both flanges, and I thus produce a crossing of the spokes which will posses an elegant appearance, while at the same time I secure great stiffness with the use of a light wire." Why should stability not be an issue 130 years later? The point was a light wheel could be constructed that was stable. His 'crossing of the spokes' was directed at the flange which was pierced with a drill'd and threaded pin into which a spoke came from opposing points of the wheel and not the interleave as used today. Here you are making your largest assumption - how do we know a patented idea really has all the benefits that are claimed? Patent examiners don't make quantitative analyses of claims, they simply verify the inventions are non-obviousness, unique and might have some utility. You should probably know that only a small fraction of inventions that are patented actually make it to market, most often because they are either impractical, or do not offer enough of an improvement over existing designs (if they offer any improvement at all). Not to mention the fact that patent examiners are not always as thorough as they could be, and patents are frequently discovered to be invalid in later investigation. For example, Rolf Deitrich managed to get issued a patent on pairing spokes in bicycle wheels, despite the fact that some of the first wire spoked wheels over 135 years ago had paired spokes! Another major assumption is that Starley had optimized his wheels on the first go-around 130 years ago. Since the actual mechanics of how loads are distributed (and how the stiffness of each component effects the load distribution) in tension spokes wheels were still not known until many years later, it is likely that Starley's wheels were not yet optimized, and were heavier than they needed to be to achieve the required strength and stiffness. Just how stiff and light were Starley's wheels? While some versions might have been as stiff as today's wheels, they were probably much, much heavier. If you are building your wheels based on a 125 year old patent, it is highly likely that your wheels are also far from optimized. Mark McMaster |
#4
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Trevor wrote:
Mark McMaster wrote in message ... For well designed and constructed wheels, the spoke breakage rate should be minimal. The expectation should be that a wheel should be able to have several worn out rims replaced without a spoke breakage (several of the wheels I have built are on their second rims with all the original spokes). I tend to agree with this posting, but know your methods differ to mine. You do not mention wheel or rim stability, is it of no concern to you? James Starley illustrates his high wheeler with 40 spokes paired together at the rim. A safety bikes wheel is half this size so 20 spokes should be sufficient for a 27" rim. Due to non pairing I think 30% less ie 14 spokes may be sufficient. I think you are making a number of assumptions. Firstly, Starley's wire spoked wheels were an innovation to make an improvement on wooden compression spoked wheels, which are by their nature very heavy. In addition, since the single row of spokes in wooden compression spoke wheels have no bracing angle, the spokes must be very broad (and heavy) to achieve the desired lateral stiffness. Starley's spokes were at a fairly wide bracing angle, even for today's smaller wheels, so they were likely able to achieve the same (or greater) lateral stiffness at less weight. We also don't know the weight and stiffness of his rim, which are also important in achieve wheel strength and stiffness. There are a number of modern 700c wheels which have a reduced number of spokes - 20, 16, 14 or even 12 spokes. However, for these wheels to to adequately stiff and strong, they need a stiff and strong rim. Using a larger number of spokes allows one to use a much lighter rim, with the resulting wheel being both lighter overall (despite their greater number of spokes), and more reliable, for the same strength and stiffness. Extract from 3959 Starley patent of 1874 "...increase their stability & improve their speed. " He mentions strength, lightness and beauty of appearance. "The spokes are screwed up until the heads of the spokes bear lightly against the rim. This arrangement I follow for the spokes of both flanges, and I thus produce a crossing of the spokes which will posses an elegant appearance, while at the same time I secure great stiffness with the use of a light wire." Why should stability not be an issue 130 years later? The point was a light wheel could be constructed that was stable. His 'crossing of the spokes' was directed at the flange which was pierced with a drill'd and threaded pin into which a spoke came from opposing points of the wheel and not the interleave as used today. Here you are making your largest assumption - how do we know a patented idea really has all the benefits that are claimed? Patent examiners don't make quantitative analyses of claims, they simply verify the inventions are non-obviousness, unique and might have some utility. You should probably know that only a small fraction of inventions that are patented actually make it to market, most often because they are either impractical, or do not offer enough of an improvement over existing designs (if they offer any improvement at all). Not to mention the fact that patent examiners are not always as thorough as they could be, and patents are frequently discovered to be invalid in later investigation. For example, Rolf Deitrich managed to get issued a patent on pairing spokes in bicycle wheels, despite the fact that some of the first wire spoked wheels over 135 years ago had paired spokes! Another major assumption is that Starley had optimized his wheels on the first go-around 130 years ago. Since the actual mechanics of how loads are distributed (and how the stiffness of each component effects the load distribution) in tension spokes wheels were still not known until many years later, it is likely that Starley's wheels were not yet optimized, and were heavier than they needed to be to achieve the required strength and stiffness. Just how stiff and light were Starley's wheels? While some versions might have been as stiff as today's wheels, they were probably much, much heavier. If you are building your wheels based on a 125 year old patent, it is highly likely that your wheels are also far from optimized. Mark McMaster |
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