Category Archives: Patents

Ralph E Thompson and the amazing tilting adjustable razor

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Ralph E Thompson was – as we’ve already seen – a rather prolific inventor of safety razors and associated gear, and he seems to have been one of the central characters in Gillette’s search for an improved, adjustable razor in the early 1930’s. As the preamble for the patent puts it:

This invention relates to safety razors, and more particularly to means for so adjusting  the razor and blade as to vary the blade edge exposure thereof. Some beards require a considerable exposure of the blade edge if a satisfactory shave is to be secured while other beards require a much less exposure. The ideas of different people vary to a great extent in this matter and, furthermore, the same person may at one time desire a close shave and. at another time a rather rough shave.

So far so good; people have different ideas of how aggressive a razor should be, and people’s needs vary from day to day. Obvious for us today, who have grown up with adjustable razors, but in the context of the time it was perhaps less so. How Mr Thompson made the razor adjustable was very different than the methods we’re used today, and when adjusted it gave the shaver an aggressive and a mild edge to shave with.. useful, perhaps, in that you could do the first pass with one side and touch ups with the second.

In accordance with my invention, I so mount and preferably pivot a stud I to the cap that movement thereof causes such a relative transverse adjustment between the blade and guard as to. secure the said variations in blade exposure, the handle being adapted to cooperate with the stud to clamp the parts in the adjusted positions.
In the accompanying drawings I have illustrated certain specific embodiments of my invention but it, will be understood that the invention can be otherwise embodied and that the drawings are not to be construed as defining or limiting the scope of the invention.

So by tilting the base plate and cap in relation to the handle, the blade gap and blade exposure could be adjusted – as can be seen in figures 4 and 6 on the drawing. A potential improvement to Mr Thompson’s invention might be to flatten the very top of the cams (labelled as #32 in the drawings) slightly, so that the neutral position could easily be found.

The patents is – naturally – long since expired, and thus available if any daring razor manufacturer wishes to market out a truly unique, infinity variable adjustable razor that gives you a mild and aggressive shave at the same time.

Kindle edition of “70 razor and shaving patents” available for preorder

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Today is a big day for me; today is the day that the kindle edition of my book 70 razor and shaving patents became available for preorder!

You can preorder it at http://getbook.at/70razor_shavingpatents – feel free to share to link to anyone interested. The official release date is March 15th 2020, and it will also be available in paperback.

New and useful Improvements in Safety-Razor-Blade Packages,

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If your freshly invented razor relies on replaceable blades, you better come up with a way to pack the blades. And that goes double if your blades isn’t perfectly flat, such as the blades for the GEM and EverReady razors.
Enter Joseph Kaufman – of the American Safety Razor Corp – and the patent he filed in January 1907 for how to package a single edge razor blade with a spine. In hindsight the invention is obvious, but it was novel enough in 1907 to be granted a patent. In the words of the patent:

The combination with a safety razor blade having longitudinal shoulders, of a paper slip of much greater length than width and open at the top and having closed ends, the blade being inserted into the slip. the shoulders of the blade resting on the upper edges of the slip and the cutting edge of the blade being a short distance inward from the bottom edge of the slip, and an envelop surrounding the blade and slip, and a retaining and sealing band surrounding the envelop, substantially as set forth.

So in short; a paper wrap around the blade – making the blade as wide as the spine and protecting the edge – and a paper envelope around that.

I got some new-old-stock Radio Steel EverReady blades – inherited from a friend of the family as part of a EverReady 1914 kit – and those blades are packet exactly as the patent describes. And when I bought modern GEM blades loose – that is, not in a dispenser – they had the card-stock wrapper around the blade proper.

 Vintage blade in outer envelope.
 Vintage blade partly out of outer envelope – the card stock can be seen through the inner envelope.
A modern blade with the card stock sleeve clearly visible.
Unlike a lot of patents I’ve looked at, part of the useful improvements in safety razor blade packaging Mr Kaufman got a patent for in 1909 is still in use hundred and eleven years later – it has certainly stood the test of time.

March 15th 2020…

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On Kindle and in paperback – preorders will be available soon!
Showcasing a selection of razor and shaving related patents – some of them important in the development of the modern safety razor, others are interesting, inessential, or plain odd – “70 razor and shaving patents” explores some of the roads not taken to get to the daily bathroom routine of making faces hairless we know and enjoy.

Square blade ends

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We might not think about it today, but those of us who uses vintage razors dating to before the mid 1930’s are actually using them with a blade they were not designed for – but the blade we’re using was designed to be compatible with them. And while the blade shown in this advertisement that ran in the June 1930 edition of Scientific American isn’t identical to the blade we know and love, it’s more than halfway there… Gillette just needed a lawsuit and a messy corporate merger with the American Safety Razor Company to get all the way there.

As an aside, this blade is probably the one covered by US patent US1850902A, filed in 1929. I might go into details on that at some point.

Comitting a book

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When I asked a few months back on my favourite shave forum if I should “comitt” a book, the responce was positive… but there was also suggestions for not just making an annotated and commented version of the book I had in mind, but also to publish a collection of my posts discussing and snarking on old patents – solutions in search of a problems, blind roads on the road to the modern shave, but also good idea that simply failed to gain traction for one reason or another.

This is taking shape as a semi-curated selection of important, interesting, inessential, and plain odd shaving related patents – a somewhat serious, somewhat humorous little rump through the patent history of razor and other shaving related accoutrement, and lavishly illustrated with the original drawings from the patent applications and a handful of other pictures used to highlight points being discussed.

The proof copies of “70 razor and shaving patents” have now reached me. This means that if I don’t spot any typos, printing errors or other flaws, it’ll probably be released for sale before Easter.

It will be availabe for Kindle and as a print-on-demand paperback from Amazon. Prices are yet to be finalized… in part because I’m not sure what a good price would be for a 220 page, lavishly illustrated book.

Shaving stick with cocoa butter core

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Believe that a shaving stick is just a shaving stick? Think again; because in 1919 Mr Joseph Kaufman of the American Safety Razor Corp – the result of the 1906 merger between the GEM and Ever-Ready companies – filed a patent for a shaving stick with new and useful improvements:

The invention relates to a novel stick of shaving soap embodying several features of advantage. The soap contained in the stick I do not modify, except to supply a first class soap therein, but I combine therewith several features of novelty, one being a central vertical core of cocoa butter or equivalent oleaginous substance, another being an elastic casing which normally incloses the stick and which may be rolled downwardly from the outer end thereof as the stick is consumed, another being a rigid base secured to the lower end of the elastic casing upon which the stick may stand vertically, and another residing, in the preferred construction, in a substantially rectangular outline in cross-section of the stick, the corners of the rectangle being rounded.

And that was just the introduction to the patent text… lets break it down, shall we?
The core of cocoa butter or other oleaginous substance1 was intended to combine with the soap to produce a efficient lather for softening the beard and protect the skin – much like many modern soaps sometimes contain cocoa butter, lotions and other skin softening ingredients. Having it as a core instead of mixed into the soap itself would mean that the fat in the cocoa butter wouldn’t react with the alkaline2 when making the soap.
The use of an elastic casing – Mr Kaufman preferred rubber, but listed pyroxylin3 as an alternative – was meant as an alternative to the then common use of tin foil on shaving sticks. The tin foil – according to the patent text – had a tendency to both fall off in patches and to scratch the face of shavers. Another benefit of the elastic casing was that you could roll it back up, protecting the stick and aiding in preserving the original character of the soap and cocoa butter.4
The rigid base – made from metal, fibre or any suitable material – would be cemented to the elastic casing and both aid the stick in standing up and prevent damage to the lower corners of the soap. Mr Kaufaman regarded – according to the patent text – the base an important but not essential part of his invention.
The reasons to have a square-ish – as opposed to round – cross section of the shave stick was quite simple; it would ensure that you had as much exposed soap despite the addition of the core.5 The fact that the shape also meant less wasted space in each box when you packed the shaving stick for shipment isn’t mentioned in the text, but it was one of the first things that stuck me.

While I would love to be able to buy a shave stick like this today, the evolution of shaving soaps have passed it by… today we have skin improving ingredients in the soap itself, the shave sticks are paper covered instead of foil, sticks tends to stand up by themselves or have plastic bases… but they are still round. A square stick would still have benefits, especially when it came to shipping.

1) Oleaginous; rich in, covered with, or producing oil; oily
2) I.e.: lye
3) pyroxylin is nitrocellulose that is less nitrated than, say, gun cotton.
4) I.e.: stop it from going rancid or drying out
5) “…the space occupied by the core of cocoa butter is recompensed for by the additional quantity of soap contained in the rectangular formation”, as the patent text states it

The invention of the modern GEM blade, with two interesting variations

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The old vintage Ever-Ready and GEM razors from American Safety Razor Corp used a single edged blade different from the GEM blade we can buy today, as can be seen in the photos of one of my old unused – practically NOS –  Ever-Ready blades and a fresh GEM blade from my stockpile.

As can clearly be seen the original Ever-Ready/GEM blade was thicker, with a much thicker spine, and had no cutouts. While you can use a modern blade in the original Ever-Ready and GEM razors – such as the 1912 and 19141 – you can’t use the original blade in a slightly more modern GEM, such as the various Micromatics. This is because the more modern razors uses the cutout to align the blade, and a blade without a cutout would stop the razor from closing properly.2
So logic dictates that the change in blade came about the same time as the GEM Micromatic was designed… Say hello to Marcus B Behrman’s patent filed and granted in 1929, describing not only what is in effect the modern GEM blade, but also the double edged single edged GEM blade I wrote about last week and a razor designed to utilise the new blade.

The invention aims primarily to provide a razor blade having special features of construction by the use of which the above mentioned adjustment of the blade with reference to the stops may be carried out with greater effectiveness and certainty, certain additional features of construction being preferably employed in the blade to insure that during assembly it will be preliminarily positioned within the proper range of action of the mechanism employed to press it against the stops.
The invention also includes a novel blade holder adapted to cooperate with a blade of the nature above referred to, to press the blade against the stops as aforesaid.

The function of, and the rationale behind, the cutouts in the blade – which was a radical departure from the original GEM blade – was quite well described in the patent:

To enable the blade to be effectively pressed against stops of the nature above referred to, I will provide it with cut-away portions and 26, located adjacent its opposite side or end edges and rearwardly of its shaving edge, these cut-away portions thereby presenting abutment shoulders 23 and 24 between t e cutaway portions and the shaving edge 20, which may be engaged by properly cooperating movable parts on a blade holder, to press the blade cutting edge against the stops on the holder as aforesaid.

The specific claims for the single and double edged variations of the blades were summarised as:

A safety razor blade having a shaving edge provided with stop engageable corner portions and cutaway portions in the central zone of the blade and in the opposite sides thereof, said cutaway portions presenting abutment shoulders therebetween and said shaving edge, said blade also having an opening between said cut-away portions with elongated linear side walls running transverse to said shaving edge to guide said stop engageable corner portions to their final predetermined stopping position.
A double edged safety razor blade having substantially parallel front and rear shaving edges provided with stop engageable corner portion, and cut-away portions adjacent opposite side edges which present abutment shoulders respectively spaced substantially equally from said front and rear edges, said blade also having an opening disposed substantially centrally between said cut-away portions, said opening being elongated in a direction transverse to said first mentioned edges and having end walls spaced substantially equally from the respective adjacent front and rear edges.

The form and function of the razor is also discussed at great length in the patent, but it’s mostly a variation on the previous GEM razors… the twist to open Micromatics must have been developed somewhat later.

As an interesting aside, a US patent filed for in 19303 also came to the surface as I was searching.
Filed by Stephen J Duritza, the preamble makes no secrets of which razor the new blade was meant for:

My present invention relates generally to razor blades and more particularly to the type of razor in which the shaving edge of the blade is to be received against front aligning stops to give such edge its predetermined position or relationship. Example of such type of razors are those known today as the “Gem” and the “Ever- Ready”.

Interestingly, the reason given for coming up with the new blade design wasn’t to simplify production, improve alignment, or give better shaves.. but to stop the corners from bending:

Where razors of this character are dropped on the floor or brought suddenly against a hard surface, it is generally the corners either of the blade seat or of the clamping cover where such clamping cover is employed, which receives the force of the impact, and may result in the bending of such corners. Where such bent corners engage the blade either at or adjacent to the shaving edge there may be the tendency in such a case for the shaving edge to be distorted from its true straight alignment for its most efficient shaving.
It is one of the objects of my invention to so arrange, treat or construct sections of the blade that this tendency to distortion under these conditions will be minimized or wholly eliminated.

Off course, not dropping your razor in the first place would been preferable – but if you do, it’s nice if you don’t have to replace the blade. What Mr Duritza did to avoid transmitting the shock of impact from the blade stops was to mechanically decouple the edge from the corners with a couple of slits. In the words of the patent:

If this fall results in a deformation of one of the aforementioned parts, this deformation would tend ordinarily to distort the non-functioning section of the shaving edge opposite thereto and this distortion would be transmitted to the active shaving edge. By providing the cuts 17 and 18 as hereinabove explained, the distortion will be taken up by the blade sections 20 or 21 as the case may be and will not be transmitted to the active shaving edge 16.

While the patent that gave rise to the modern GEM blade resulted in production that goes on to this day, Mr Duritza’s patent seems to have gone no where… perhaps the bending of the blade edge from dropping the razor was less of an issue than the inventor believed it to be? The Double Edged GEM blades also seems to have gone the way of the dinosaurs, sadly, but in the days before stainless blades I’m not too surprised about that – by the time you got to flip the blade over, the humidity and soap residue might have done a number on the second edge.

1) It will rattle a little until you close the razor, and a bit of care has to be taken – at least with my 1914 – to make sure it’s aligned properly.
2) This backward compatibility is similar to how you can use a modern slotted double edge blade in an original Gillette Old, but you can’t use a three holed blade in a Gillette Super Speed.
3) not granted until almost five years later though; the wheels of bureaucracy turns slowly at times.

Gillette’s thin, rigid razor blade

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Razor blades – by which I mean the traditional double edged blade – is flexible. This is because it’s made out of thin steel, even thinner now than when King Gillette first though them up.1 But flexible blades needs a rigid holder – better known as a safety razor – and as we all know a razor costs money up front. Imagine how many more blades you could sell if the holder – the razor – was significantly cheaper?
This seems to have been the logic behind the patent that Alfred W Proctor filed on behalf of the Gillette Safety Razor Company in 1912. In the words of the patent text:

This invention relates to razor blades of a type now widely used and made of thin sheet steel, as distinguished from forged blades. The facility with which such blades can be manufactured because they do not require forging in order to bring them to shape and because many of the grinding processes incident to the production of a forged razor are unnecessary, has brought them into wide use. Blades made from such thin sheet steel, however, have an inherent flexibility which requires, or at least, makes it desirable to employ With them a holder which embodies a backing, this holder operating to support the blade and impart a certain degree of rigidity to the cutting edge. Such holders are however expensive to make and are undesirable for various reasons.

The holder that supports the blade and imparts a certain degree of rigidity to the blade that Mr Proctor refers to is – as all of you probably realises – the actual razor itself. Personally I cannot see the razor being undesirable for any reason, but it’s certainly true that the double edged blade requires both a bottom plate and a top cap to hold the blade securely and to prevent the blade from vibrating and chatter.
So how did Mr Proctor plan to make the Gillette safety razor – which had been on the market for less than a decade when this patent was filed – obsolete? By making the blade stiff enough to do without the rigidity of the holder – ie.: the razor – much like a straight edge razor. Not by making the blade out of thicker materials, but making it thicker by putting ribs or ridges in it.

In order to impart the necessary or desirable rigidity referred to the blades will be given a configuration which affords such rigidity so that the blades because of their configuration are stiffened.

For the exact same reason that an I-beam is stiffer than a plate, a blade with ridges is stiffer than a blade without.2 And if the blade is stiff and rigid, you can do without the complex holder – that is; the razor. And thus we end up with the invention shown in the patent drawing: A blade with ribs arranged to make it stiff both along it’s length and breath, and a razor that was little more than some bent wire.

The blade may be used in a wire frame such as C which operates merely as a holder and does not impart any appreciable degree of support to the blade.

I think that when all is said and done we ought to be happy Gillette didn’t go down this road, since we would have missed out on so many fun and wonderful razors in the last century.

1) For more details, see my previous blog post on how old razors shaved back when new. The quick summary is that modern blades are half as stiff – or twice as flexible – as the original blades.
2) For the technical details, read up on Euler–Bernoulli beam theory, also known as engineer’s beam theory or classical beam theory. The quick, oversimplified summary is that the taller the web (or the ridges, in the case of this patent) the stiffer the beam (in this case; blade).

Combined comb and hair cutter

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Long time readers of my blog will – perhaps – recall I posted a quick little post about a home made hair trimmer made with a comb, a razor blade and some painters tape a few years ago. To no one’s surprise this wasn’t a new idea – you can buy a dozen variations in all sort of shapes from Chine – but I found an early patent that seems to be inspired by the top cap of a Gillette razor.
Applied for by Mr Domenico Marrazzo in the fall of 1935, the device was claimed to be for the head as well as other parts of the body.

… a combined comb and hair cutter, wherein the blade is so guarded as to prevent accidental i6 cutting of the fingers and to permit the hair cutting portion to be used as a handle when the comb portion is used as a comb.

So hold one end of the device, and it’s a comb. Hold the other end, and it’s a hair cutter. Hope that you remember which end is which when you brush your hair before going on your big date.

It’s a simple enough idea in hindsight – like most good inventions are – and Mr Marrazzo took care to point out that you could make it from almost anything, ad that it would be usefull for anyone regardless of hair length:

The comb may be made of any suitable material such as hard rubber, bakelite or metal such as aluminum or the like.

Said arcuate portion is somewhat greater in length than the length of the blade 14 and has a convex outer surface 11 and a concave inner surface 13 as shown in Figs. 2 and 3. In order that the device may be operative in cutting long hair as well as short hair, the row of teeth 20 on one side of the comb are preferably longer and if desired, coarser than the opposed row 21 on the other side.

All told it sounds like a useful combination tool for those who like to trim their own hair – as highlighted by the fact that variations on this theme is still for sale.