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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to automatic gain control in a zero intermediate frequency radio device such as a receiver or transceiver. Such a radio device processes down-converted and demodulated received radio frequency signals, and, when a transmit part is also present, transmits modulated and up-converted signals. Such radio devices can be cellular radio, cordless telephony, or, wireless local area network radio devices, satellite radio devices, or any other suitable radio device.
2. Description of the Related Art
From the handbook “RF and Microwave Circuit Design for Wireless Communications”, L. E. Larson, Artech House Publishers, 1996, page 73, a Direct-Conversion zero-IF receiver is known. In such a receiver, a local oscillator comprised in the receiver is tuned to a carrier frequency of the incoming radio frequency signal. When DC-coupling stages in such a direct conversion zero-IF receiver, serious problems are caused by DC-offset such as due to LO-leakage to an input of a low noise radio frequency amplifier that is usually present between an antenna and a mixer of the zero-IF radio device, and further due to DC-offset in various components of the radio device, such as in channel filters, amplifiers, or in other components. To mitigate such DC-offset problems, AC-coupling is provided in the receive branch of the radio device. Such an AC-coupling can be distributed over various stages whereby all stages are designed such that the DC-offset of a stage is much smaller than the dynamic range of that stage.
In the U.S. Pat. No. 5,982,807, an intermediate frequency spread spectrum radio transceiver is disclosed for use in wireless local area network, in the so-called 2.4 GHz ISM band as defined in the IEEE 802.11b standard. In the transceiver, a baseband processor comprises a demodulator for spread spectrum phase shift keying (PSK) demodulating information received from a radio circuit comprised in the transceiver. In addition to a bi-phase or binary PSK mode (BPSK), the transceiver can operate in a quadrature PSK mode (QPSK). The demodulator is connected to an output of an analog-to-digital converter. The analog-to-digital converter is AC-coupled to the radio circuit. For substantially reducing an average DC-component, a particular type of Walsh code is used. As shown in FIG. 1 of U.S. Pat. No. 5,982,807, the wireless transceiver has an antenna, an up/down converter, and a Tx/Rx-switch. The up/down converter is connected to a low noise radio frequency amplifier in a receive branch of the transceiver, and to a radio frequency power amplifier in a transmit branch of the transceiver. The up/down converter is connected to a frequency synthesizer and to an IF modulator/demodulator. The transceiver further comprises various filters, and voltage controlled oscillator. A baseband processor comprise high speed 3-bit analog to digital converters for receiving the quadrature I and Q signals from the modulator/demodulator. Furthermore, the baseband processor includes a received signal strength indicator monitoring function with a 6-bit analog to digital converter.
On page 62 of the DRAFT Supplement, Part 11, to the above IEEE 802.11b standard, operating channels are shown for North American Channel Selection. With a local oscillator in the radio tuned to 2412 MHz, the zero-IF radio device receives radio signals from the shown non-overlapping Channel 1 .
In the U.S. Pat. No. 5,982,235, an automatic gain control circuit (AGC) is disclosed which is used for mobile communication. As shown in FIG. 7 of U.S. Pat. No. 5,982,235, the gain of an amplifier is set. The amplifier that amplifies an input IF signal, has a gain control function. The thus-amplified signal is output to a demodulation circuit. For application of an AGC in mobile communication, as described, a receiving level changes as great as +10 dB or more to −30 dB or less. In order to take care of a significant drop in the receiving level in excess of the range of control of the AGC, such as due to a fading phenomenon, the shown automatic gain control circuit comprises a fading detection circuit at IF (RSSI), an AGC convergence level setting circuit, a signal-to-noise (S/N) detection circuit, and an AGC setting circuit. The S/N detection circuit that is connected to an output of the amplifier provides one input signal to the AGC convergence level setting circuit. The RSSI provides another input signal to the AGC convergence level setting circuit. The AGC circuit further comprises an attenuation setting circuit coupled to an output of the amplifier. The output signal of the AGC circuit occurs at an output of the attenuation setting circuit. The RSSI detects whether the AGC circuit is on the move at high speed. If this is the case, the AGC convergence level setting circuit controls the AGC convergence level so as to increase or decrease, thereby preventing loss of data. If this is not the case, the ratio of an output signal to noise and the output signal level are maintained at constant levels. If a fading occurs, the level of AGC convergence is increased thereby preventing deterioration of the ratio of the output signal to noise. The attenuation circuit is set such that the level of the output signal remains constant.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an automatic gain controller in a zero intermediate frequency radio device with AC-coupled stages, whereby a signal resolving range of a received signal strength indicator is below a high dynamic range exhibited by an incoming radio frequency signal.
It is another object of the invention to provide such an automatic gain controller that stepwise iterates to providing an output signal to be sampled in a linear range of the received signal strength indicator, either by initially starting with a maximum gain or with a minimum gain.
It is still another object of the invention to provide such an automatic gain controller that first kicks off by modifying the gain of the low noise radio frequency amplifier (LNA) where the largest DC-offset problems exist and where the effect of out-of-band jammers can be reduced by decreasing the gain of the LNA.
It is still another object of the invention to reduce the negative effects of AC-coupling after the AGC has settled, by reducing the cut-off frequency of the AC-coupling.
It is still another object of the invention to distribute gain control over components of the receive branch between the antenna and the signal processor for processing the zero-IF signal.
In accordance with the invention, a zero intermediate frequency radio device is provided comprising:
an antenna for receiving a radio frequency signal, said radio frequency signal exhibiting a high dynamic range;
a frequency down converter for down converting said radio frequency signal to a zero intermediate frequency signal, said frequency down converter comprising a mixer, an AC-coupler, and a received signal strength indicator with a signal resolving range that is below said high dynamic range, said AC-coupler being coupled to an output of said mixer;
a signal processor for processing said zero intermediate frequency signal;
at least one amplifier coupled between said antenna and said signal processor; and
an automatic gain controller for at least gain controlling said at least one amplifier,
said automatic gain controller being configured to set a gain of said at least one amplifier by setting said gain to a predetermined gain, by waiting a predetermined time for allowing DC-offset signals in said radio device to decay, by checking whether a reading of said received signal strength indicator is within said signal resolving range, and by setting said gain in accordance with said reading if said reading is within said signal resolving range.
The invention is based upon the insight that in zero intermediate frequency radio device with AC-couplers, the AGC can only be set if no signal saturation at the output of the RSSI occurs, due to DC offsets.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows a block diagram of a zero intermediate frequency radio device according to the invention.
FIG. 2 shows an AGC settling table according to the invention, and a first step of gain setting.
FIG. 3 shows an AGC settling table according to the invention, and a second step of gain setting.
FIG. 4 shows LO-leakage that causes a DC-offset signal at an output of a mixer in the radio device, and an AC-coupler that is coupled to the output of the mixer.
FIG. 5 shows an error signal at an output of the AC-coupler as a function of time.
FIG. 6 shows AC-coupling and channel filtering of a zero intermediate frequency signal in a radio device.
Throughout the figures the same reference numerals are used for the same features.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a block diagram of a transceiver 1 as a zero intermediate frequency radio device according to the invention. The transceiver 1 comprises a receive branch Rx and a transmit branch Tx. In another embodiment in which no transmit branch Tx is present, the radio device is a receiver. The transmit branch Tx comprises a quadrature mixer having filters 2 and 3 , mixers 4 and 5 , and a summing device 6 , and further a transmit power amplifier 7 coupled to the quadrature mixer. At input side, the quadrature mixer is coupled to a baseband circuit with a modulator (not shown in detail). At output side, the transmit power amplifier 7 is coupled to a Tx/Rx-switch 8 . The Tx/Rx-switch 8 is coupled to an antenna 9 . Such a transmit branch is well-known in the art. The receive branch Rx comprises a variable gain low noise radio frequency amplifier (LNA) 10 that is coupled to the Tx/Rx-switch 8 . The LNA 10 amplifies an output signal V sig that corresponds to an incoming radio frequency signal RF that is received by the antenna 9 . The radio frequency signal RF, received in channel 1 of the so-called 2.4 GHz band as defined in said IEEE 802.11b standard, for instance, exhibits a high dynamic range, typically 80 dB, from −90 dBm to −10 dBm. An output 11 of the LNA 10 is coupled to a frequency down converter 12 for down converting the radio frequency signal RF to a zero-IF signal V in . Shown is a quadrature frequency down converter. The frequency down converter 12 comprises mixers 13 and 14 in respective quadrature and in-phase mixer paths that provide filtered and amplified quadrature signals Rx_Q and Rx_I. The frequency down converter 12 further comprises controllable AC-couplers 15 , 16 , 17 , and 18 , controllable channel filters 19 , 20 , 21 , and 22 , and zero-IF amplifiers 23 and 24 . The AC-couplers 15 and 17 are coupled between the mixers 13 and 14 and the zero-IF amplifiers 23 and 24 , respectively. The AC-couplers 16 and 18 are coupled between the channel filters 19 and 20 , and between the channel filters 21 and 22 , respectively. 25 is provided for controlling gains of the amplifiers 10 , 23 and 25 , and for controlling gains and other parameters of the channel filters 19 , 20 , 21 , and 22 . A signal V out is shown at an output of the AC-coupler 15 . Control signals on the control bus 25 are provided by an AGC controller comprised of a signal processor 26 in a baseband circuit 27 , of a state machine 28 , and of an AGC bus controller 29 . The signal or micro processor 26 comprises ROM and RAM (not shown in detail) for storing non-volatile program data, and for storing volatile data for use with the program data. The state machine 28 controls the AGC bus controller 29 , and further provides cut-off frequency control signals to the AC-couplers 15 , 16 , 17 , and 18 . Once the functionality of the state machine has been defined, a person skilled in the art will have no difficulty in implementing the state machine, in the form of a so-called ASIC (Application Specific Integrated Circuit), for instance. In another embodiment in which signal processor has dedicated I/O-ports, the state machine 28 can be dispensed with. In such an embodiment, the programmed signal processor provides all necessary control signals. The baseband circuit 27 further comprises analog to digital converters 30 and 31 for sampling the quadrature signals Rx_I and Rx_Q. The sampled Rx_I and Rx_Q signals are supplied to a demodulator (not shown in detail here). The transceiver 1 further comprises a frequency synthesizer 32 comprising a PLL for generating local oscillator signals for the receive branch Rx and for the transmit branch Tx. As is well-known in the art, the PLL comprises a voltage controlled oscillator (VCO) 33 and a loop filter 34 . A reference oscillator signal (not shown) is supplied to the PLL. In order to generate a 2412 MHz LO signal for ISM channel 1 , the 1.2 GHz VCO signal is multiplied by two. For generating ninety degrees phase shifted LO signals that are fed to the mixers 13 and 14 in the receive branch Rx, and to the mixers 4 and 5 in the transmit branch, a 90 degrees phase shifter 35 is coupled to the multiplied by two VCO signal. The transceiver 1 further comprises a received signal strength indicator (RSSI) comprised of squarers 36 and 37 , a summer 38 , a low pass filter (LPF) 39 , a logarithmic ampifier (LOG) 40 , and an analog to digital converter 41 . The sampled RSSI signal is supplied to the state machine 28 or to the signal processor 26 , depending on the particular embodiment.
FIG. 2 shows an AGC settling table according to the invention, and a first step of gain setting, and FIG. 3 shows the AGC settling table according to the invention, and a second step of gain setting.
After the receiver is switch on, the AGC should settle within 10 μsec. The state machine 28 and the signal processor 26 , that form an AGC controller, are programmed to implement AGC settling in accordance with the invention. In a first embodiment, initially, the gain of the receive path Rx is set to maximum gain MAX_GAIN. In a second embodiment, initially, the gain of the receive path Rx is set to minimum gain MIN_GAIN. In the first embodiment, exhibiting a faster AGC settling time than the second embodiment, small amplitude radio signals are resolved first, at maximum gain. In the second embodiment, large amplitude radio signals are resolved first, at minimum gain. The first embodiment will now be described in detail. Initially, the AGC-code is set to zero. In the given example, the analog to digital converter 41 is a 5-bit converter, so at its output it produces a digital code between 0-31. It is assumed that the RSSI circuit operates linearly over a 32 dB input signal range (safe range) for a range of output digital codes 0-31. Outside such a 0-31 range, it is assumed that a reading of the analog to digital converter 41 is not a reliable representation of the actual received radio frequency signal RF. Therefore, only a part of the RF signal's dynamic range of 80 dB can be sampled. The AGC settling table 50 shows the required AGC attenuation versus RF input signal level, as an example. A reading of the RSSI is indicated with an arrow. Under these assumptions, at maximum gain, all readings corresponding to greater than 31 are rejected, and the AGC is not set. Too high a setting of the gain, at a low radio frequency signal strength, would, at only a small DC-offset in the Rx path, easily saturate signals in the Rx path. To avoid such a saturation, the AC-couplers 15 , 16 , 17 , and 18 are provided. I.e., as indicated in the AGC table 50 , initially, at maximum gain, only radio frequency signals between −90 dBm and −60 dBm can reliably be indicated by the RSSI. In the given example, radio frequency signals in the 80 dB dynamic signal range are coded 0-80. With such a coding, the AGC can be settled with an accuracy of 1 dB. Other mappings of codes to signals, with a different AGC settling accuracy, may be applied, as will be readily understood by a person skilled in the art. With a reading of code=15, for instance, at maximum gain, within a code range of 0-31, no saturation occurs. Then, the AGC can be set by reducing the gain in the Rx path with 15 dB, from maximum gain. When setting the gain in the Rx path to a particular gain value it is essential to wait until all DC-offset in the Rx path has been removed, in all stages thereof before actually using the I&Q output signals. Based on the assumption that the maximum DC-offset of each stage is known, depending on modifying a gain of a particular stage, a waiting time for the DC-offset to cancel is set. The largest DC-offset is to be expected due to LO-leakage from the VCO+frequency doubler to the input of the low noise radio frequency amplifier 11 . Other stages, after the mixers 13 and 14 , typically exhibit a lower DC-offset. A waiting time for DC-offset to at the input of the LNA 11 to cancel, is typically set 2-3 μsec. For other stages, a waiting time is typically set to 1 μsec. With a reading of code=31, at maximum gain, saturation occurs. Then, the AGC cannot be set and a further step is needed, similar to the above described step of gain setting and waiting for DC-offset to cancel. In the further step, from maximum gain, the gain in the Rx path is reduced by 31 dB. This means that in the further step, radio frequency signals can be indicated with a signal strength between −59 dBm and −29 dBm. In this further step, the AGC-code is set to 31. Also in this further step, it essential to wait until DC-offset due to a change in gain setting has been cancelled. With a reading of code=2, for instance, the AGC can still not be set, because, due to still too high a gain of the Rx path, the reading code=2 still saturates the Rx path at the I&Q A/D input. Then, a still further step is needed, similar to the above two steps. In a next step, the gain is reduced by 2 dB. In the given example, the actual input signal is −57 dBm. In the second embodiment, starting off at minimum gain, similar steps are performed, until the RSSI reading falls in a range of codes corresponding to the RSSI reading, and finally setting the RSSI to read zero.
FIG. 4 shows LO-leakage that causes a DC-offset signal at an output of the mixer 13 in the radio device 1 , and the AC-coupler 15 that is coupled to the output of the mixer 13 . Further shown are the frequency spectra of the signals V sig and V in , and decay of the DC-offset V out, DC due to LO-leakage to the input of the LNA 11 as a function of time, at the output of the AC-coupler 15 . In the example given, the gain of the LNA 11 can be set in two steps, to +20 dB or to 0 dB. For a 1 MHz cut-off frequency of the AC-coupler 15 , at a gain change of the LNA 11 of 20 dB, initially a huge DC-offset is present due to a low leakage at the input of the LNA 11 . The waiting time for the DC-offset to cancel is set such that waiting occurs until V out, DC is smaller than V sig /10. At a cut-off frequency of 1 MHz, the waiting time is typically 3 μsec. Due to an initially relatively high cut-off frequency of the AC-coupler 15 , a notch in its frequency spectrum occurs. Such a notch causes the RSSI to indicate an incorrect measurement of the radio frequency signal RF. It is thus advantageous to reduce the cut-off frequency of the AC-coupler 15 , after the AGC has settled. Furthermore, the higher the cut-off frequency of the AC-coupler 15 , the worse the signal-to-noise ratio. So, after AGC has settled, the cut-off frequency of the AC-coupler is reduced by reducing the time constant RC of the AC-coupler 15 , as indicated. The resistor R can be varied continuously, or in steps.
FIG. 5 shows an error signal V error at an output of the AC-coupler 15 as a function of time t. At t=t 0 , the cut-off frequency of the AC-coupler 15 , and also of the AC-coupler 16 is 1 MHz. At t=t 1 , when complete AGC gain has been set, the cut-off frequency is reduced to 100 kHz. Eventually, at t=t 2 , the cut-off frequency is further reduced to 10 kHz, effectively removing AC-coupling to a very large extent. This leads to a gradual reduction of the signal V error to lower than 10% of the signal V in .
FIG. 6 shows a frequency characteristic 60 of AC-coupling and a frequency characteristic 61 of channel filtering of a zero intermediate frequency signal in the radio device 1 , and further a frequency spectrum 62 of the zero-IF signal at an output of the mixer 15 .
After the AGC has set, it is advantageous to reduce the gain to a received signal strength indicator input by 10 dB, in order to detect both an increase or a decrease in signal level later on. Gain to the input of the received signal strength indicator can be reduced through controllable attenuators (not shown in detail here) coupled between the Rx_Q and Rx_I outputs and the squarers 36 and 37 . The nominal set point for the RSSI will then be ten instead of zero, and will indicate signal changes of +10 dB to −22 dB, beyond which it will saturate.
Also, a larger range RSSI can be used for this purpose, e.g. a range of 42 dB. This will give a signal change reading of +10 dB to −32 dB. In this embodiment, readings between 0 and 31 will be used for AGC, whereas readings between −10 and −1 are used for the above purpose.
In the embodiments given, gain reduction, channel filtering, and reduction of cut-off frequencies can be distributed over many stages. When reducing gain of the Rx path, from maximum gain to a lower gain, it is advantageous to first reduce the gain of the LNA 11 . Similarly, when increasing the gain of the Rx path, from minimum gain to a higher gain, it is advantageous to increase the gain of the LNA 11 in a last step. Such a gain setting mitigates the effects of out-of-band jammers or interferers in other channels of the ISM band. Furthermore, at a lower gain setting, the radio front end becomes more linear.
In view of the foregoing it will be evident to a person skilled in the art that various modifications may be made within the spirit and scope of the invention as hereinafter defined by the appended claims and that the invention is thus not limited to the examples provided. The word “comprising” does not exclude the presence of other elements or steps than those listed in a claim. | A zero intermediate frequency radio device has an antenna for receiving a radio frequency signal, and a frequency down converter for down converting the received radio frequency signal to a zero intermediate frequency signal. The radio device further has controllable amplifier stages, controllable AC-coupling stages, controllable filter stages, and a received signal strength indicator. A signal resolving range of the received signal strength indicator is below a high dynamic range of the received radio frequency signal. The radio device further has an automatic gain controller. The automatic gain controller initially sets the gain of the Rx path of the radio device to a maximum of minimum gain, and then waits for DC-offsets in the Rx path to cancel. If, at maximum or minimum gain, a reading of the received signal strength indicator is within a particular range, the automatic gain controller sets the gain to the reading. Then, automatic gain control settles. If this is not the case, the gain of the Rx path is stepwise decreased or increased, while repeating the DC-offset cancellation step of waiting for the DC-offset to cancel, until the reading of the received signal strength indicator falls in the signal resolving range around the then set gain of the Rx path. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application U.S. Ser. No. 61/843,158 filed Jul. 5, 2013, the entire contents of which is herein incorporated by reference.
FIELD
[0002] The present invention relates to probiotic compositions for oral administration. In particular, the present invention relates to probiotic compositions with beneficial effects, such as improved health, especially oral health, and methods of administration of the compositions.
BACKGROUND
[0003] An oral cavity, e.g. mouth, shelters numerous and varied microbial flora. When the equilibrium is compromised and when an imbalance appears amongst the indigenous bacteria, pathologies such as dental caries or periodontitis can occur. Probiotics are live microorganisms that may confer a health benefit on the host. The beneficial effects of probiotic therapy are achieved in part through the modulation of existing microbial flora associated with the host, thus attaining a balanced and healthy microbes-host relationship. In relation to the oral cavity, probiotic compositions may help to restore a balanced bacterial population, thereby improving oral health.
[0004] Dental caries is a ubiquitous infectious disease typically transmitted through caregivers in childhood, which persists throughout life or until complete edentulism. Dental caries is predominantly managed through antimicrobial preventative approaches like tooth brushing or flossing which are effective largely because of their antimicrobial action. Recent advances in Cariology have led to a better understanding of the broader microecological context of caries formation, which presents opportunities for new microbial based prophylactic treatment strategies and technologies to be applied in caries management.
[0005] The infection of the initiating pathogenic bacteria involved in caries are mutans streptococci group bacteria, most notably Streptococcus mutans that encapsulates within a biofilm of insoluble exopolysaccharides self-generated from sucrose. This adherent plaque, provides and ecological niche where the pathogenic bacteria thrive and produce various organic acids from carbohydrates that progressively dissolves the tooth minerals. The more contemporary understanding of caries development now includes the context of microbial, ecological, and environmental factors, where an alteration or imbalance in the microfloral ecology predisposes one to caries formation. To this end, probiotic therapies have been suggested as having potential to be an effective means of regulating S. mutans and the oral microflora (Caglar 2005a; Saha 2012; Tagg 2003) and there has been significant clinical research of individual strains' potential use as probiotics (Näse 2001; Taipale 2012; Keller 2011; Stecksén-Blicks 2009; Burton 2013; Caglar 2008; Caglar 2006; Caglar 2005b).
[0006] The ostensible mechanism by which various strains combat dental caries varies case by case. For example some strains have anti- S. mutans activity by aggregating with the S. mutans , while others directly kill or inhibit S. mutans by secreting specific bacteriocins, and others still colonize the plaque and compete with S. mutans for its ecological niche. The potential therefore exists for complementary synergistic effects of combining these mechanisms. For another example, two probiotic strains may secrete different bacteriocins that, because of their varying biochemical target within the S. mutans , may have greater combined S. mutans killing effect than either on their own.
[0007] Probiotic compositions may also be enhanced in certain circumstances through the addition of prebiotics to the composition. A prebiotic “feeds” microbial flora, so as to enhance a beneficial bacterial subpopulation; a probiotic adds beneficial cultures to populations of microbial flora. The term “synbiotic” describes a composition that contains both prebiotics and probiotics, for example, one that contains both fructooligosaccharides (FOS) (a prebiotic) and bifidobacteria (a probiotic). Research in the area is devoted to the synergy between the types of ingredients to obtain a better understanding of how growth and survival of probiotics may be enhanced by the presence of complementary prebiotic ingredients.
[0008] Although a large number of probiotic compositions are known, each composition has unique characteristics and particular health benefits. One example of a probiotic composition with a benefit for oral health is described in commonly-owned U.S. Provisional application U.S. Ser. No. 61/674,390 filed Jul. 22, 2012, which discloses a probiotic combination including Streptococcus salivarius K12® (BLIS K12®) and at least five Lactobacillus bacteria.
[0009] However, there is always a need for improved formulations of probiotic compositions, particularly formulations that result in one or more of improved oral health, improved oral colonization, improved efficacy, improved shelf-life, efficacy for different and specific oral diseases, and additional improvements, as well as methods of administration or uses thereof.
SUMMARY
[0010] In one aspect of the invention there is provided a composition for use in oral hygiene, comprising an oral hygiene effective amount of a probiotic, the probiotic comprising a Lactobacillus helveticus strain.
[0011] In a second aspect of the present invention, there is provided a composition for use in oral hygiene, comprising an oral hygiene effective amount of a probiotic, the probiotic comprising a Lactobacillus helveticus strain and a Lactobacillus plantarum strain.
[0012] In a third aspect of the present invention, there is provided a composition for use in oral hygiene, comprising an oral hygiene effective amount of a probiotic, the probiotic comprising a Lactobacillus helveticus strain and Bifidobacterium longum SD5846.
[0013] In a fourth aspect of the present invention, there is provided a composition for use in treating or preventing dental caries, comprising a dental caries preventing effective amount of a probiotic, the probiotic comprising Lactobacillus plantarum SD5870.
[0014] In a fifth aspect of the present invention, there is provided a composition for use in treating or preventing dental caries, comprising a dental caries preventing effective amount of a probiotic, the probiotic comprising Bifidobacterium longum SD5846.
[0015] In a sixth aspect of the present invention, there are provided uses of the aforementioned probiotics for oral hygiene.
[0016] In a seventh aspect of the present invention, there are provided uses of the aforementioned probiotics for the preparation of a medicament for oral hygiene.
[0017] In an eighth aspect of the present invention, there is provided a method of treating or preventing an oral condition or disease in a subject, comprising orally administering an aforementioned probiotic to the subject.
[0018] In an ninth aspect of the present invention, there is provided a commercial package comprising an aforementioned probiotic and instructions for its use in oral hygiene.
[0019] The probiotic comprises or consists essentially of a Lactobacillus helveticus strain. The probiotic may comprise or consist essentially of a Lactobacillus helveticus strain and one or more other probtiotic bacteria, preferably from the lactobacilli, bifidobacteria and/or streptococci genii, more preferably one or more other lactobacilli, yet more preferably one other lactobacillus . The probiotic may comprise or consist essentially of both a Lactobacillus helveticus strain and a Lactobacillus plantarum strain, especially Lactobacillus plantarum SD5870 (known commercially as Lactobacillus plantarum Lp-2001). The phrase “consists essentially of” indicates that other probiotic bacteria are not present, or are present in inconsequential amounts. The Lactobacillus helveticus strain preferably comprises Lactobacillus helveticus LAFTI L10, Lactobacillus helveticus R0052 or a mixture thereof. The Lactobacillus helveticus strain more preferably comprises Lactobacillus helveticus LAFTI L10.
[0020] For treating or preventing dental caries specifically, the probiotic may alternatively comprise Lactobacillus plantarum SD5870 or Bifidobacterium longum SD5846. The probiotic preferably comprises Lactobacillus plantarum SD5870 in combination with one or both of Streptococcus salivarius M18 and Streptococcus salivarius K12. Preferably, the probiotic consists essentially of Lactobacillus plantarum SD5870, or consists essentially of Lactobacillus plantarum SD5870 and one or both of Streptococcus salivarius M18 and Streptococcus salivarius K12 such that other probiotic bacteria are not present, or are present in inconsequential amounts.
[0021] Oral hygiene comprises the prevention or treatment of conditions or diseases of an oral cavity. Such conditions or diseases include, for example, dental caries (cavities), halitosis, gingivitis, mouth ulcers including aphthous stomatitis (canker sores), candidiasis and periodontal diseases. In one aspect of the invention, Streptococcus mutans population in the oral cavity is suppressed leading to better oral health. In a particularly preferred embodiment, dental caries is prevented. Subjects for which this invention is useful include, for example, mammals. Subjects may include primates, humans or domesticated animals. Some examples of domesticated animals are dogs, cats and horses.
[0022] The composition may comprise from about 0.0001% to about 100% by weight of the probiotic, based on total weight of the composition. Optionally, the probiotic may be from about 0.001% to about 50% by weight, or from about 0.001% to about 10% by weight, or from about 0.001% to about 5% by weight of the composition. Oral hygiene effective amounts of the probiotic in the composition depend to some extent on the age of the subject, the type of probiotic bacteria, dosing frequency, dosage form, administration method and variability in the subjects' commensal oral microflora. For example, dosages of the probiotic in a range of about 10 7 to 10 11 colony forming units (CFU) are generally suitable; particularly for lozenges, dosages of the probiotic in a range of about 10 8 to 10 10 CFU per lozenge are preferred, the optimal amount depending on the strain or strains of probiotic in the composition and the frequency of administration, which can vary from 1 to 4 lozenges per day. Administration of the probiotic may be performed at any convenient time, for example during or after teeth brushing, or during or after meals.
[0023] Compositions comprise the probiotic and may comprise other ingredients generally known in the art, for example one or more remineralization agents, prebiotics, carriers, diluents, excipients and the like. The other ingredients are preferably pharmaceutically acceptable or at least acceptable for use in the oral cavity.
[0024] S. mutans functions in decaying the tooth matrix through the secretion of acids that dissolve minerals calcium and phosphate. After several months of acid secretion, the demineralization will then spread to the enamel and eventually to the dentine. Although reversible at this phase, further progression will lead to cavity formation, and necessitate tooth restoration. Saliva plays an important role not only as a natural buffer to the offending acids, but also as a source of calcium and phosphate for remineralization of the teeth, naturally arresting or even reversing the pathology. Dental caries formation then is a dynamic equilibrium of demineralization by pathogenic bacteria and remineralization. Interventions and prophylactic treatments often focus on tipping the balance towards remineralization by adding agents to this effect. Remineralization agents include, for example, casein phosphate peptide-amorphous calcium phosphate (CPP-ACP), β-tricalcium phosphate, nanoparticles of amorphous calcium phosphate (NACP), hydroxyapitite, calcium glycerophosphate or other variants of calcium and phosphate. The re-mineralization agent can be added in an amount of from 1 to 10 wt % of the composition, preferably from 1 to 4 wt %. Fluoride is also added to many dental products as it is an effective catalyst of remineralization, and incorporates into the crystalline structure resulting in a more resistant tooth surface than the original. Notably casein phosphate peptide-amorphous calcium phosphate (CPP-ACP) (see U.S. Pat. No. 7,491,694, the disclosure of which is herein incorporated by reference) is particularly effective because the bound peptide derived from a milk protein binds and stabilizes the calcium phosphate into a soluble amorphous from that is readily bioavailable. The combination of a probiotic formulation that prevents the demineralization, together with a remineralization agent, especially CPP-ACP, would be expected to have even greater effectiveness in the prophylactic treatment of dental caries.
[0025] Inclusion of prebiotics in the composition enhances probiotic effectiveness in certain circumstances. A prebiotic mainly functions to feed microbial flora. The term “synbiotic” describes a composition that contains both prebiotics and probiotics. Some examples of prebiotics that may be useful in the present invention include, for example, mono-, di- and oligo-saccharides such as manose fructans, fructooligosaccharides (FOS), xylooligosaccharides (XOS), polydextrose and galactooligosaccharides (GOS), lactulose, tagatose, inulin, maltodextrin, lactitol and mixtures thereof. In general, the amount of prebiotic used is much greater than the amount of probiotic, for example gram amounts of prebiotic may be used for milligram amounts of probiotic.
[0026] Carriers, diluents and excipients for oral compositions are generally known the art and include, for example, absorbents, acidifying agents, alkalizing agents, binders, buffers, coatings, colors, controlled-release agents, controlled-release carriers, diluents, disintegrants, effervescent agents, flavors, glidants, lubricants, plasticizers, solubility enhancers, wetting agents, surfactants, preserving agents, sweetening agents, flavouring agents, etc. Some specific examples include lactose, dextrose, fructose, sucrose, sorbitol, mannitol, starches, gum acacia, calcium phosphate, alginates, tragacant, gelatine, calcium silicate, polyvinylpyrrolidone, cellulose (e.g. microcrystalline cellulose), water syrup, water, water/ethanol, water/glycol, water/polyethylene glycol, propylene glycol, methyl cellulose, methylhydroxybenzoates, propyl hydroxybenzoates, talc, magnesium stearate, mineral oil or fatty substances such as hard fat or suitable mixtures thereof.
[0027] A particularly preferred class of excipients is sugar substitutes, which act as sweeteners with a reduced or negligible effect on blood glucose levels. Preferably, the sugar substitutes are non-cariogenic. Such sugar substitutes include, for example, sugar alcohols (e.g. isomalt), stevia, aspartame, sucralose, neotame, acesulfame potassium and saccharin. Stevia and isomalt are of particular note. Stevia is based on steviol glycosides and comprises an extract of the plant Stevia rebaudiana . Isomalt is an equimolar mixture of two disaccharides, each composed of two sugars glucose and mannitol (α-D-glucopyranosido-1,6-mannitol) and also glucose and sorbitol (α-D-glucopyranosido-1,6-sorbitol). Isomalt in particular improves stability of the compositions of the present invention. Certain sugar substitutes (e.g. isomalt) may also be considered to be prebiotics.
[0028] Compositions of the present invention may be administered to the subject orally in oral or topical dosage forms. Suitable dosage forms include, for example, tablets (e.g. effervescent tablets and/or multi-layered tablets), pills, powders, lozenges (including multi-layered lozenges), sachets, cachets, elixirs, suspensions, emulsions, solutions, syrups, aerosols, capsules, pastes (e.g. toothpaste), food and confectionary (e.g. chewing gum). Formulation of such dosage forms is well known in the art. Compositions of the present invention have good stability maintaining effective CFU count of the probiotic strains over a period of at least 24 months, even over a period of at least 30 months, at room temperature (20-25° C.). Shelf life can be extended beyond 36 months in certain storage conditions (e.g., refrigerated conditions at 2-8° C.) and/or various delivery systems such as sachets/powder sticks.
[0029] The composition may be provided in the market place in the form of a commercial package together with instructions for use of the composition for oral hygiene.
[0030] Commercial packages include, for example, bottles, jars, blister packs, boxes, etc. Instructions may be provided, for example, in visual or audio forms, for example, in writing, in pictures, on sound and/or video recording media, or combinations thereof.
[0031] Further features of the invention will be described or will become apparent in the course of the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] In order that the invention may be more clearly understood, embodiments thereof will now be described in detail by way of example, with reference to the accompanying drawings, in which:
[0033] FIG. 1 depicts a schematic diagram of culture plates showing bacterial swabbing zones and how zones of inhibition (ZOls) are determined.
[0034] FIG. 2 depicts a 1.5% agarose gel of PCR amplicons of a species specific DNA segment of the S. mutans chromosome. Type strain S. mutans 25175 was used as a positive control.
[0035] FIG. 3 depicts a graph showing quantification of deferred antagonism experiments of probiotics individually and in all possible combinations of two against S. mutans 25175. Experiments were repeated at least 4 times using BHI agar pH balanced with 0.1% CaCO 3 .
[0036] FIG. 4 depicts a graph showing quantification of deferred antagonism experiments of probiotics individually and in all possible combinations of two against freshly isolated S. mutans 13. Experiments were repeated at least 4 times using BHI agar pH balanced with 0.1% CaCO 3 .
[0037] FIG. 5 depicts a graph showing quantification of deferred antagonism experiments of probiotics individually and in all possible combinations of two against freshly isolated S. mutans 14. Experiments were repeated at least 4 times using BHI agar pH balanced with 0.1% CaCO 3 .
[0038] FIG. 6 depicts a graph showing quantification of deferred antagonism experiments of probiotics individually and in all possible combinations of two against freshly isolated S. mutans 15. Experiments were repeated at least 4 times using BHI agar pH balanced with 0.1% CaCO 3 .
[0039] FIG. 7 depicts a table showing synergistic antagonism against strains of S. mutans for different combinations of probiotic strains with anti-microbial characteristics. Comparison was made to component strains individually by one-way ANOVA with data from at least four individually repeated experiments.
[0040] FIG. 8 depicts a table showing comparison of the relative production of hydrogen peroxide of probiotic strains. +++ within 24 hours, ++ within 48 hours, + within 72 hours, and—no production.
[0041] FIG. 9 depicts a graph showing adhesion of various probiotic strains, and strains of S. mutans to human bronchial epithelial cell line 16HBE14o-.
[0042] FIG. 10 depicts a graph showing comparison of the aggregation of various probiotic strains with S. mutans 25175. Comparison was made by one-way ANOVA with Bonferroni post hoc test (*p<0.05, **p<0.01, ***p<0.001).
DETAILED DESCRIPTION
[0043] Throughout the specification reference is made to genus/species names and to strain designations. From time to time the classification of organisms changes and any given organism may be assigned a different name and/or strain designation. The probiotic organisms referred to herein have certain genomes that would remain the same whether or not the name and/or strain designation of the organisms changes. From the genome, one skilled in the art can readily determine whether any given organism, whatever name and/or strain designation it carries, is encompassed by the present description.
EXAMPLE 1
S. mutans Isolation and DNA Extraction
[0044] Plaque was collected using sterile probes and spread directly onto mitis salivarius-bacitracin S. mutans selective agar from 4 different subjects, and then incubated for 48 hours at 37° C. in microaerophilic conditions. Individual colonies were then quadrant streaked onto BHYE plates and then incubated again for 48 hours at 37° C. in microaerophilic conditions. Subsequent genotyping was undertaken on the isolated colonies to confirm their species. Bacterial DNA extracted using InstaGene Matrix (BioRad) similar to manufacturer's instructions. Briefly, a single colony was picked and dispersed in 1 mL of sterile H 2 O. This mix was then centrifuged for 1 minute at 10,000 rpm and the supernatant discarded. To the pellet was added 200 μL of IntaGene Matrix, the samples were vortexed quickly and incubated at 55° C. for 20 minutes in a water bath. Samples were then removed and incubated in a boiling water bath for 30 minutes. The samples were then vortexed again and then centrifuged for 3 minutes at 10,000 rpm. Supernatants were collected and stored at −20° C. until used for PCR.
[0045] All PCR reagents were obtained from Invitrogen. Samples of extracted DNA were subjected to PCR in a reaction mixture containing 1× PCR buffer, 15 mM MgCl 2 , 200 mM dNTP mix, 10 μM MUT-F primer, 10 μM MUT-R primer, 5 U of Taq DNA polymerase, 10 μL of DNA template, and ddH 2 O up to a final volume of 50 μL. The primers amplify a 517-bp DNA region coding the gtfB extracellular glucosyltransferase of S. mutans (Oho 2000).
[0000]
(SEQ ID NO: 1)
MUT-F: 5′-ACT ACA CTT TCG GGT GGC TTG G-3′
(SEQ ID NO: 2)
MUT-R: 5′-CAG TAT AAG CGC CAG TTT CAT C-3′
[0046] The thermocycling conditions were an initial denaturation at 95° C. for 1 minute, followed by 30 cycles of denaturation at 95° C. for 30 seconds, annealing at 59° C. for 30 seconds, and extension at 72° C. for 1 minute. A final extension step at 72° C. for 5 minutes was included. PCR products were then mixed with DNA loading buffer and separated with a 1.5% agarose gel with 0.05% EtBr at 100 V for 45 minutes, and imaged under UV light excitation.
EXAMPLE 2
Deferred Antagonism
[0047] To test the antagonism of the probiotics against S. mutans , deferred antagonism was undertaken essentially as previously performed by Tagg and Bannister (Tagg 1979). Liquid cultures were inoculated into MRS for either lactobacilli or bifidobacteria, and BHYE for streptococci, and then incubated overnight at 37° C. in microaerophilic conditions. Referring to FIG. 1 , the overnight suspension was then swabbed onto a BHI or CB plate with 0.1% (w/v) CaCO 3 in a measured 1 cm wide streak using sterile cotton swabs. BHI plates contained 18.5 g brain heart infusion (BHI, Difco), 7.5 g agar (Fisher) and 1 g CaCO 3 (Sigma). CB plates contained 22 g Columbia blood (Difco), 7.5 g agar (Fisher) and 1 g CaCO 3 (Sigma). The plates were then incubated at 37° C. in microaerophilic conditions. After 48 hours the bacterial growth was scraped off with a glass microscope slide, and the plate re-sterilized with chloroform vapors for 20 minutes. Overnight suspensions of the type strain S. mutans ATCC25175 and 4 fresh isolates were then streaked across perpendicularly, and the plates were re-incubated. After 48 hours the zone of inhibition (ZOI) was calculated as the distance between the two areas of bacterial growth, minus 1 cm where the probiotic was directly plated. Statistics was performed using Prism 4 (GraphPad). One-way ANOVAs were used to compare between specific probiotics and probiotic combinations. Synergism was calculated as a synergistic quotient, which is the sum of the individual treatments divided by the combined treatment. A values >1 indicate synergism of the combination (Wang 2012).
[0048] To determine strains with probiotic potential in dental caries, an S. mutans antagonism screening was undertaken for many commercialized strains of probiotics. Firstly, as described in Example 1, fresh isolates of the pathogen were obtained by plating plaque samples from 4 individuals onto S. mutans selective mitis salivarius-bacitracin agar plates. Colonies were genotyped for the presence of an S. mutans specific marker sequence, which was compared against the type strain S. mutans ATCC 25175 ( FIG. 2 ). Four isolates were selected (1 per subject).
[0049] Deferred antagonism assays against these 4 isolates and S. mutans 25175 was undertaken on two media types to rapidly screen probiotic strains with any antagonism. Table 1 indicates the presence or absence of a zone of inhibition (ZOI) for any replicate, and for any of the 5 strains assayed in these experiments. Strains Streptococcus salivarius K 12, Streptococcus salivarius M18, Lactobacillus plantarum SD5870, L. helveticus R0052, and Bifidobacteria longum SD5846 (known commercially as Bifidobacteria longum Bl-05) were observed to have antagonism on both agar types, while for Lactobacillus helveticus LAFTI L10 antagonism was only apparent on BHI agar. BHI agar was therefore used in subsequent quantitative deferred antagonism experiments. To quantify the antagonism, the experiment was repeated for each probiotic bacteria in at least four and as many as eight separate experiments, and the zone of inhibition was specifically measured. Equal mixtures of all probiotic bacterial strains in all possible combinations of 2 were assessed to test for potential synergistic effects. The ZOI of five pathogenic strains was measured and averaged across four experiments. The results are indicated in FIG. 3 to FIG. 6 .
[0050] In general, the culture collection strain of S. mutans proved to be much more resistant to antagonistic factors secreted by the probiotics compared to fresh isolates ( FIG. 3 ). For example in single probiotic experiments, no antagonism was observed at all for the S. mutans 25175, while for S. mutans 13, all 6 probiotics except B. longum SD5846 were antagonistic. As a single strain L. helveticus LAFTI L10 and L. helveticus R0052 were able to antagonize all four freshly isolated S. mutans , while S. salivarius K12, and L. plantarum SD5870 antagonized three of four. S. salivarius M18 antagonized two of the four pathogenic isolates, and B. longum SD5846 only one, and the average ZOI for these were, in all cases, comparatively weaker than other probiotic strains.
[0000]
TABLE 1
Presence or absence of a ZOI based on qualitative
observations of deferred antagonism assays against
five S. mutans strains.
Strain
CB
BHI
S. salivarius K12
+
+
S. salivarius M18
+
+
S. thermophilus R0083
−
−
S. thermophilus St-21
−
−
L. rhamnosus GG
−
−
L. plantarum SD5870
+
+
L. paracasei Lp-37
−
−
L. salivarius Ls-33
−
−
L. acididophilus La-14
−
−
L. reuteri Lru-1038
−
−
L. plantarum Lp-115
−
−
L. rhamnosus Lr-32
−
−
AAP-2
−
−
L. helveticus R0052
+
+
L. helveticus LAFTI L10
−
+
L. casei Lc-11
−
−
B. lactis BI-04
−
−
B. breve BI-03
−
−
B. bifidum R0071
−
−
B. longum R00175
−
−
B. longum SD5846
+
+
[0051] The average ZOI were in many cases greater when two strains were combined together in equal amounts and certain bacteria appeared to combine better than others. For isolate S. mutans 15 for example ( FIG. 6 ), of the 15 possible combinations of 2 strains, 7 were greater than the ZOI of L. helveticus R0052, the greatest inhibiting individual probiotic. Of these 7 combinations, six contained either a L. helveticus LAFTI L10 or a L. plantarum SD5870. This proved true across all pathogenic strains; in each instance of inhibiting S. mutans isolates 13, 14, 15, and 17, or even S. mutans 25175, the 4 largest ZOI were always combinations containing either a L. helveticus LAFTI L10 or a L. plantarum SD5870.
[0052] FIG. 7 indicates the average zone of inhibition (ZOI) together with the calculated synergism of the antagonism. Significant difference of the ZOI as calculated by 1-way Anova for combinations compared to its component strains individually is indicated. The synergistic quotient (SQ) indicates the relative synergism by dividing the ZOI for combinations of probiotics by the sum of their component ZOI measured individually. Combinations with greater than 50% synergism (SQ >1.5) are indicated in bold. NA indicates no antagonism, while US indicates undetermined synergism, as antagonism was only ever observed in combination. The combination of L. helveticus LAFTI L10 with B. longum SD5846 and the combination of L. plantarum SD5870 with L. helveticus R0052 were both significantly more antagonistic against strains of S. mutans than their individual components. The combination of L. helveticus LAFTI L10 with B. longum SD5846 was very synergistic with US, 1.8, 3.7, 2.4, and 2.2 when tested against S. mutans strains 25175, 13, 14, 15, and 17, respectively. L. plantarum SD5870 with L. helveticus R0052 was also synergistic, exhibiting an SQ of NA, 3.3, 1.5, 1.8, and 1.6, respectively.
[0053] Interestingly, however, component bacteria from each of these two synergistic combinations ( L. helveticus LAFTI L10 and L. plantarum SD5870) resulted in particularly strong activity, and synergism when combined together. The ZOI for these 2 strains combined was the highest antagonism by a significant margin for all five strains of S. mutans . The ZOI for L. helveticus LAFTI L10 and L. plantarum SD5870 was in fact higher than the ZOI for the two strains individually added together for all strains of S. mutans , which proved highly significant by 1-way ANOVA. For S. mutans 25175 there was no inhibition at all by either probiotic strain individually, but very significant inhibition (about 20 mm) when the two strains were combined together. This is strongly suggestive of synergistic activity between the probiotics, and in fact the synergistic quotients were US, 3.4, 3.9, 4.2 and 4.2 for strains of S. mutans 25175, 13, 14, 15, and 17, respectively.
EXAMPLE 3
Hydrogen Peroxide Production
[0054] To test hydrogen peroxide production, a commonly used methodology was employed that is very similar to that recently used by Kang et al (Kang 2011). Essentially, standard agar growth media (MRS for either lactobacilli or bifidobacteria, and BHYE for streptococci) was modified by the addition of 0.25 mg/mL 3,3′,5,5′-tetramethylbenzidine
[0055] (TMB) and 0.1 ng/mL peroxidase. Briefly, 0.125 g of TMB and 5 mg of peroxidase was dissolved in 1 mL of dimethyl sulfoxide (DMSO) and water respectively. These solutions were sterilized using 0.2 μm syringe filters and added to 0.5 L of liquid agar media immediately following post autoclave cooling to <50° C. Plates were then poured. Individual colonies of probiotic were picked from a stock plate, and streaked directly onto TMB/peroxidase agar and standard agar control plates using an inoculation loop. Plates were then left at 37° C. in microaerophilic conditions for 72 hours. The colonies and surrounding agar were assessed for any change in color to either blue or red every 24 hours by comparing to a normal MRS or BHYE streaked control plate. The experiment was repeated three times.
[0056] Since many lactobacilli produce hydrogen peroxide as an antagonistic agent against surrounding bacteria, the hydrogen peroxide production of the strains was assayed. It was confirmed that 10 of the 11 lactobacillus strains tested produced some hydrogen peroxide. S. salivarius did not while the two S. thermophilus and all 5 of the bifidobacteria produced varying degrees of H 2 O 2 ( FIG. 8 ). All strains that were observed to have S. mutans antagonism were all among the fastest to produce H 2 O 2 , having been observed to do so within 24 hours of plating, with the exception of S. thermophilus.
EXAMPLE 4
Cell Surface Adhesion
[0057] Cell culture reagents were obtained from GIBCO unless otherwise stated. The immortalized human bronchial epithelial cell line 16HBE14o- was grown in MEM media supplemented with 10% FBS and 2 mM L-glutamine, and maintained using standard cell culture procedures at 37° C. and 5% CO 2 . Cells were seeded in wells of a tissue-culture treated 24-well plate at a concentration of 1×10 5 cells/well and allowed to grow to confluency (about 48 hours, approximately 5×10 5 cells/well). Cell media was then aspirated and replaced with 500 μL of fresh media containing 100-fold dilutions of the various stationary phase bacterial cell suspensions, which were grown overnight in MRS (lactobacilli and bifidobacteria) or BHYE (streptococci). Plates were then incubated at 37° C. and 5% CO 2 . After 5 hours, the culture media was aspirated and the monolayers washed thoroughly three times with PBS to remove non-loosely adherent bacteria. Eukaryotic cells were then disrupted by adding Triton™ X - 100 to a final concentration of 0.1%. Enumeration of the remaining adherent CFUs contained in the lysis suspension was then undertaken by drop plate method. Serial dilutions up to 10 −6 were made in a 96 well plate in 10-fold steps, with 10 μL of the various dilutions then spotted in triplicate onto appropriate agar (MRS for lactobacilli and bifidobacteria, and BHYE for streptococci). The agar plates were incubated at 37° C. in microaerophilic conditions for 24 hours, after which
[0058] CFUs were enumerated. Adhesion was reported as total CFUs divided by the number of bronchial cells in the well as determined by cell counts of a bacteria-free control well of 16HBE14o- cells.
[0059] To deliver its effects, the bacteria would have to co-localize with the S. mutans within the oral cavity. To test the potential of the probiotic bacteria to stay within the oral cavity, binding affinity assays were performed ( FIG. 9 ). The assay tested adherence of the bacteria to a monolayer of 16HBE14o- human bronchial epithelial cells, which share a cell linage with oral epithelial cells and resemble them in phenotype. Bacteria were seeded into MEM media and allowed to grow for 5 hours before the free bacteria were washed away, and CFU counts made of the remaining disrupted eukaryotic and bacterial cell mixture. It was found that in general, the S. mutans pathogens did not adhere well to the cells, and nor did the lactobacilli tested ( FIG. 9 ). The S. salivarius , which were originally isolated from the human throat, however adhered very tightly by comparison.
EXAMPLE 5
Co-Aggregation with S. mutans
[0060] The various probiotic bacteria or S. mutans were inoculated into 1 mL of liquid MRS for either lactobacilli or bifidobacteria, or BHYE for streptococci, and then incubated overnight at 37° C. in microaerophilic conditions. The tubes were then centrifuged at 2000 rpm for 5 min and the supernatant aspirated, and then re-suspended in 1 mL PBS. This step was repeated 3 times. The suspended cells were then serially diluted in 100 μL PBS up to 128-fold in 2-fold serial dilution steps in a 96 well plate. The absorbance was read from the plate at 600 nm using an EON microplate reader (BioTek). From the resultant data absorbance versus dilution curves were created, and the dilution for an absorbance of 0.3 was extrapolated for each bacterium tested. Triplicate wells containing 200 μL of suspended bacteria were diluted directly in a 96 well plate according to the extrapolation. For each bacterium 100 μL of the same dilution was also added together with 100 μL of diluted S. mutans . The mixtures were uniformly dispersed by pipetting the wells up and down with a multichannel pipette. The plate was then sealed with a sterile clear plastic film, and then immediately incubated in the microplate reader at 37° C. along with a PBS blank. The wells were read at 600 nm after 6 hours.
[0061] The potential of the strains to adhere and interact directly with the S. mutans through an aggregation assay was also assessed ( FIG. 10 ). Individual strains, and also equal part mixtures with S. mutans were assayed for absorbance changes at 600 nm when incubated at 37° C. An elevated absorbance indicates faster settling as a result of aggregation, when compared to either strain individually. The experiment shows that S. mutans does not auto-aggregate without a biofilm. However the addition of either strain of L. helveticus (LAFTI L10 or R0052) led to a significantly increased absorbance compared to either bacterium alone.
EXAMPLE 6
Discussion of In Vitro Effects
[0062] It has been here demonstrated that unique properties of particular strains of bacteria have the potential to modify the oral micro-floral environment for the amelioration of oral health and the reduction in dental caries causing S. mutans . This conclusion is underpinned by the specific finding that strains of the species L. helveticus (LAFTI L10 and R0052) inhibit pathogens S. mutans better than all strains tested including S. salivarius M18 and L. rhamnosus GG, which are well established strains in the treatment of dental caries.
[0063] Secondly, there is substantial and significant synergism between the strains L. plantarum SD5870 and L. helveticus LAFTI L10 in their combined ability to inhibit five strains of freshly isolated S. mutans as well as a S. mutans strain that is very pathogenic. The co-aggregation of and L. helveticus LAFTI L10 with S. mutans in vitro further underscores its strong potential to localize and deliver its effects in the oral cavity. Finally, the probiotic combination was shown to have synergistic S. mutans -reducing potential when combined together in an in vitro model of dental caries. This finding is unexpected since we had previously observed that the combination of two or more different probiotics normally resulted in poorer inhibition than any one of the probiotics alone. Combinations may generally lead to poorer inhibition because the different probiotics in the combination may compete with each other as well as inhibit each other. Even maintaining inhibition at the same level as compared to a single probiotic is unexpected, let alone finding synergy between combinations of probiotics.
[0064] Several bacterial strains have reliably been demonstrated to affect dental caries pathogens through various mechanisms. Notably, S. salivarius M18 was shown both in in vitro and in clinical studies to have an anti- S. mutans activity. There was also considerable clinical research interest demonstrating the probiotic Lactobacillus rhamnosus GG to have anti-dental caries effects in short term and long term studies. In the present invention it was demonstrated that several strains of probiotic bacteria exceeded these probiotics in their S. mutans antagonism. While no antagonism of the S. mutans strains was observed using L. rhamnosus GG, considerable antagonism was observed using S. salivarius M18. It is notable however that several strains of probiotic tested including L. plantarum SD5870, and B. longum SD5846, and the related strain S. salivarius K12, were all observed to have greater antagonism than S. salivarius M18 for at least one strain of S. mutans , while the two L. helveticus strains studied (LAFTI L10 and R0052) had in fact greater or equal antagonism for all strains tested.
[0065] Of greatest interest is that when the strain L. helveticus LAFTI L10 was combined with L. plantarum SD5870, strong anti- S. mutans synergism was observed for all five pathogens tested. The observed antagonism was stronger for this combination than for any other individual probiotic strain or combination tested, and was at least three times more effective at antagonizing than the two individual probiotics added together, for all five of the S. mutans strains.
[0066] Although it is unknown what metabolic mechanisms underlay the synergism, it is known that some strains of L. helveticus secrete bacteriocins like helveticin J, and helveticin V-1829, and likewise strains of L. plantarum have a variety of bacteriocins and other antimicrobial substances coded at the pln locus, whose secretion is regulated through a quorum mechanism. Though it is unknown whether L. plantarum SD5870 expresses any antimicrobial factors, their expression though variable is thought to be relatively common among L. plantarum strains. Antimicrobial peptides that antagonize S. mutans may be particularly effective in combinations of complementary lethality when secreted by the two probiotics.
[0067] It is interesting that the 4 non-streptococci strains that had S. mutans antagonism were all among the strongest H 2 O 2 producers. While S. salivarius K12 and M18 may exert anti- S. mutans activity through secretion of specific bacteriocins, it appears likely that L. plantarum SD5870 and Lactobacillus helveticus LAFTI L10 do so at least partially through the secretion of H 2 O 2 . S. mutans is reported as being able to both produce and degrade hydrogen peroxide, but is nevertheless also readily susceptible to it, presumably at threshold concentrations. Levels of hydrogen peroxide localized around S. mutans in vivo, may be further increased by the direct aggregation that was observed of L. helveticus LAFTI L10 with S. mutans , and thereby act as an additional factor by which a high degree of antagonism is achieved.
[0068] The findings here support the conclusion that L. helveticus has significant antagonism against S. mutans , and further that the specific combination of L. helveticus LAFTI L10 and L. plantarum SD5870 act synergistically to antagonize and inhibit the growth of S. mutans in an in vitro model of oral health. These findings have significant implications for microbiological-based treatment strategies of dental caries.
EXAMPLE 7
In-Vivo Effects
[0069] In-vivo effects may be determined as follows. A randomized, double blinded, placebo controlled clinical trial is conducted with 30-40 subjects per group. Subjects are treated with equal doses of a minimum of 1 billion CFU L. helveticus LAFTI 110 and L. plantarum SD5870 twice daily in a probiotic lozenge following brushing for a period of 28-30 days. A decrease in the detection of precarious demineralised surface area of >20% may be expected as determined using highly sensitive frequency-domain infrared photothermal radiometry and modulated luminescence. A decrease in S. mutans and plaque levels is also expected.
[0070] It is anticipated that the addition of casein phosphate peptide-amorphous calcium phosphate (CPP-ACP) or other remineralization agent will demonstrate significant in vivo effects as follows. A randomized, double blinded, placebo controlled clinical trial is conducted with 30-40 subjects per group. The study would comprise 4 arms as follows: a first treatment group where subjects are treated with equal doses of a minimum of 1 billion CFU L. helveticus LAFTI 110 and L plantarum SD5870; a second treatment group where subjects are treated with a combination of 1 billion CFU L. helveticus LAFTI I10 and L plantarum SD5870 and an effective dose of CPP-ACP or other remineralization agent; a third treatment group where subjects are treated with an effective dose of CPP-ACP or other remineralization agent; and a fourth treatment group where subjects are treated with a placebo control. The study would continue with twice daily doses in probiotic lozenges following brushing for a period of 28-30 days. A decrease in the detection of precarious demineralised surface area of >20% may be expected as determined using highly sensitive frequency-domain infrared photothermal radiometry and modulated luminescence. A decrease in S. mutans and plaque levels is also expected.
EXAMPLE 8
Lozenge Formulation and Stability
[0071] 7/16-inch round lozenges are formulated in accordance with Table 2.
[0000]
TABLE 2
Amount per
Ingredient
Lozenge (mg)
Lactobacillus helveticus LAFTI L10
45
Lactobacillus plantarum Lp-2001 (SD-5870)
25
S. salivarius M18 (BAA-2593)
6
Recaldent ™ (CPP-ACP)
20
Isomalt
160
Fructose
100
Microcrystalline Cellulose
70
Dextrose
50
Stearic Acid
15
Dicalcium Phosphate
10
Citric Acid
6
Cherry Pomegranate Flavor (natural)
3
Total
510
[0072] Sealed packages of the lozenges are stored at room temperature (20-25° C.) at an ambient humidity of 60-65%. Bacteria are cultured from the lozenges at defined time points according to an industry standard selective spread plate method. Thus, lozenges are dissolved in phosphate buffered saline (PBS), serially diluted, and plated onto selective agar for S. salivarius (CABK12) and Lactobacilli (Rogosa) agar plates in triplicate. CFU counts are made following 48 hour incubation at 37° C. in microaerophilic conditions. Even after 27 months, there are still substantial live probiotic strains with at least about 4×10 8 CFU/lozenge. There are substantial and adequate numbers of live bacteria to deliver probiotics health benefits.
EXAMPLE 9
Deferred Antagonism in Prior Art Products
[0073] Commercially available probiotic products were tested with the deferred antagonism assay described above. Table 3 provides the probiotic bacterial composition for each product.
[0000]
TABLE 3
Tested
CFU/
Product
Probiotic bacteria
lozenge
A
S. salivarius K12 and M18
3.97 × 10 5
B
Lactobacillus rhamnosus , L. plantarum , L. reuteri ,
9.72 × 10 8
L. paracasei , L. salivarius , S. salivarius
K12
C
Streptococcus uberis KJ2, S. oralis KJ3, S. rattus
2.2 × 10 9
JH145
D
L. reuteri DSM 17938 ( L reuteri Protectis ™)
9.17 × 10 6
E
L. reuteri DSM 17938, L. reuteri PTA 5289
3.67 × 10 7
[0074] In brief, one lozenge of each product was dissolved in 5 mL of 1× PBS by shaking for 2 h at 37° C. in sterile conditions. Then, with the help of a cotton swab, the dissolution was spread within a 1 cm wide streak across the diameter of BHI and BHI supplemented with CaCO 3 agar plates. These plates were incubated for 48 h at 37° C. in microaerophilic conditions, then the grown bacteria were removed and the agar was sterilized. After, 5 different strains of S. mutans (ATCC strain and Integra's isolates 13, 14, 15 and 17) were swabbed across the plates, perpendicularly to the probiotic streak and left to grow for another 48 h. This procedure was repeated twice, each of them using triplicates for each condition. Unlike compositions of the present invention, no growth inhibition was observed for any of the six replicates of each condition for any of the commercially available probiotic products tested.
[0075] It should also be noted that the probiotic bacterial count of about 4×10 8 CFU/lozenge after 27 months of storage of a lozenge of the present invention as described in Example 8 compares very favorably with the prior art products that were tested, and is considerably better than over half of the prior art products tested.
REFERENCES
[0076] The contents of the entirety of each of which are incorporated by this reference.
Burton J P, et al. (2013) The influence of the probiotic Streptococcus salivarius M18 on indices of dental health in children: a randomised double-blind placebo-controlled trial. Journal of medical microbiology . doi:10.1099/jmm.0.056663-0. Caglar E, Kargul B, Tanboga I. (2005a) Bacteriotherapy and probiotics' role on oral health. Oral diseases. 11, 131-7. Caglar E, et al. (2005b) Effect of yogurt with Bifidobacterium DN-173 010 on salivary mutans streptococci and lactobacilli in young adults. Acta odontologica Scandinavica. 63, 317-20. Caglar E, Cildir S K, Ergeneli S, Sandalli N, Twetman S. (2006) Salivary mutans streptococci and lactobacilli levels after ingestion of the probiotic bacterium Lactobacillus reuteri ATCC 55730 by straws or tablets. Acta odontologica Scandinavica. 64, 314-8. Caglar E, et al. (2008) Short-term effect of ice-cream containing Bifidobacterium lactis Bb-12 on the number of salivary mutans streptococci and lactobacilli. Acta odontologica Scandinavica. 66, 154-8. Kang M-S, et al. (2011) Inhibitory effect of Lactobacillus reuteri on periodontopathic and cariogenic bacteria. Journal of microbiology (Seoul, Korea). 49, 193-9. Keller M K, Hasslöf P, Stecksén-Blicks C, Twetman S. (2011) Co-aggregation and growth inhibition of probiotic lactobacilli and clinical isolates of mutans streptococci: an in vitro study. Acta odontologica Scandinavica. 69, 263-8. Näse L. et al. (2001) Effect of long-term consumption of a probiotic bacterium, Lactobacillus rhamnosus GG, in milk on dental caries and caries risk in children. Caries research. 35, 412-20. Oho T, Yamashita Y, Shimazak, Y, Kushiyama M, Koga T. (2000) Simple and rapid detection of Streptococcus mutans and Streptococcus sobrinus in human saliva by polymerase chain reaction. Oral microbiology and immunology. 15, 258-62. Saha S, Tomaro-Duchesneau C, Tabrizian M, Prakash S. (2012) Probiotics as oral health biotherapeutics. Expert opinion on biological therapy. 12, 1207-20. Stecksén-Blicks C, Sjöstrom I, Twetman S. (2009) Effect of long-term consumption of milk supplemented with probiotic lactobacilli and fluoride on dental caries and general health in preschool children: a cluster-randomized study. Caries research. 43, 374-81. Tagg J R, Bannister L V. (1979) “Fingerprinting” beta-haemolytic streptococci by their production of and sensitivity to bacteriocine-like inhibitors. Journal of medical microbiology. 12, 397-411. Tagg J R, Dierksen K P. (2003) Bacterial replacement therapy: adapting “germ warfare” to infection prevention. Trends in biotechnology. 21, 217-23. Taipale T, Pienihäkkinen K, Salminen S, Jokela J, Söderling E. (2012) Bifidobacterium animalis subsp. lactis BB-12 administration in early childhood: a randomized clinical trial of effects on oral colonization by mutans streptococci and the probiotic. Caries research. 46, 69-77. Wang J. et al. (2012) Synergistic effects of nanosecond pulsed electric fields combined with low concentration of gemcitabine on human oral squamous cell carcinoma in vitro. PloS one. 7, e43213.
[0092] The novel features of the present invention will become apparent to those of skill in the art upon examination of the detailed description of the invention. It should be understood, however, that the scope of the claims should not be limited by the preferred embodiments set forth in the examples, but should be given the broadest interpretation consistent with the specification as a whole. | Compositions for use in oral hygiene contain a Lactobacillus helveticus strain. Compositions further containing a Lactobacillus plantarum strain, especially Lactobacillus plantarum SD5870, are particularly effective. The combination of Lactobacillus helveticus LAFTI L10 and Lactobacillus plantarum SD5870 synergistically improves oral hygiene. The compositions are particularly useful against dental caries. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention:
This invention relates to frieze vents for buildings.
2. Description of the Prior Art:
It has long been the practice that in order to seal the space between the roofing material and outside walls of a building, bounded on the end by rafters, a so-called frieze board would be constructed by carefully measuring the spaces between the rafters, cutting notches in a long board to fit around the rafters and nailing the boards in place. Vent holes are sometimes provided, which holes may be covered with screen wire. This method of construction and installation of a frieze board has been an arduous and time consuming task.
Various devices have been used in the prior art to avoid the use of the above described method of construction and installation. Typical examples in the prior art are U.S. Pat. No. 1,651,071, issued Nov. 29, 1927 to J. C. Scheppers; U.S. Pat. No. 2,969,726, issued Jan. 31, 1961 to T. J. Bottom; U.S. Pat. No. 3,125,942, issued Mar. 24, 1964 to L. L. Smith; U.S. Pat. No. 3,256,654, issued June 21, 1966 to E. D. Pinckney, Jr.; U.S. Pat. No. 2,991,709, issued July 11, 1961 to D. D. Haddix; U.S. Pat. No. 3,051,071, issued Aug. 28, 1962 to R. L. Leigh; and U.S. Pat. No. 3,777,649, issued Dec. 11, 1973 to W. A. Luckey.
The Smith, Pinckney, Haddix and Leigh devices all disclose ventilator modules used in installations wherein the vents are parallel with the ground. Additionally, they do not disclose devices for convenient fittings about rafters.
The Scheppers and Bottom devices disclose the expedient of ventilators installed between adjacent rafters and outside walls in a full or partially vertical position but fail to disclose means for enclosing the space under the rafters securely nor do they disclose a method of solidly locking the screening material with the rafter connectors in a convenient slide and snap connection manner after the rafter connectors have been installed.
The Luckey device discloses the expedient of a prefabricated apparatus for occupying the space between the roofing material and the outer walls of a building bounded by two adjacent rafters but does not use a vent system terminating evenly with the building wall nor a rafter connector equipped to enclose a rafter and engage adjacent vents on either side of the rafter. The unit is also expensive to construct.
The problems of having a prefabricated, easily installed structure capable of compensating for variable distance rafter spacings and warpage is solved by the rafter vent of this invention. The vent can be prefabricated because it is adjustable to variations in the normal size of the space between the rafters and the warpage of the rafters, as well as providing a rafter connection unit for two adjacent vent screens.
SUMMARY OF THE INVENTION
The present invention is a prefabricated sheet of metal, plastic or other material which is used to occupy the space between the roofing material and the finished material on the outside walls of a building in combination with a rafter connector. This space is caused by the vertical dimension of the rafters which raised the roofing material above the outside walls.
Preferably, the rafter vent is fabricated in a number of sizes designed to conform to various dimensions and spacing of the rafters, and it is provided with means for adjusting its dimensions to accommodate variations in the normal sizes of the openings and warpage of the rafters. It is perforated, if desired, to a degree to allow ventilation of the attic space enclosed but at the same time to exclude the entry of birds and large insects. The invention is provided with a rafter bracket per rafter, preferably including ears and a tongue in order that the rafter vent may be easily installed by connection to the rafters.
BRIEF DESCRIPTION OF THE DRAWINGS
For a further understanding of the nature and objects of the present invention, reference should be had to the following detailed description, taken in conjunction with the accompanying drawings in which like parts are given like reference numerals and wherein:
FIG. 1 is a perspective view of a building using the preferred embodiment of the rafter vent device of the present invention showing two vents installed.
FIG. 2 is a back perspective view of the rafter bracket of the preferred embodiment of the rafter vent device of the present invention.
FIG. 3 is a back perspective view partially in hidden line of the vent of the preferred embodiment of the rafter vent device of the present invention.
FIG. 4 is a partially exploded, partially assembled front perspective view of two rafter brackets with a vent therebetween of the preferred embodiment of the rafter vent device of the present invention.
FIG. 5 is a top, cross sectional view of the vent of the preferred embodiment of the rafter vent, taken along section lines 5--5 of FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a building structure having rafters 1 supporting roofing materials 2. Because of the vertical dimensions of the rafters, openings 3 are formed between the roofing material 2 and the outer walls 4 of the building. The rafter vent 5 of this invention is used to cover that opening and is held in place by attaching ears 6 (See FIG. 2) to rafters 1.
The assembled rafter bracket 5 is usually assembled (See FIG. 4) as a combination of three parts, two rafter brackets 10 (See FIG. 2) and one vent 7 (See FIG. 3).
Referring now to FIG. 2, a back perspective view of the rafter bracket 10 of the rafter vent 5 shows ears 6 used to attach rafter vent 5 to rafters 1, as by means of nails, for which holes 6a may be provided. Additionally, holes 6a may be provided with burrs 11 for driving into rafter 1 as a temporary means to hold the rafter bracket 6 in place until it can be nailed or otherwise secured. Burrs 11 are not necessary if, for example, an air driven staple gun or similar securing mechanism is used. Tongue 12 is connected at 14 to sides 16 of ears 6. The lower edge 18 of tongue 12 is connected to base 20. Tongue 12 and base 20 may be a single piece of metal, or alternately connections 14 and the connection at lower edge 18 may be by welding, soldering or other suitable connection process. The upper portion 22 of tongue 12 is free above connection 14 for resilient bending, and is arcuately curved back over the base 20. Ears 6 are also connected to shoulder supports 24 by creases 26 either as a continuous piece of metal or by welding or other suitable connection process. The top 28 of each of shoulder supports 24 of rafter bracket 10 is curved over the base 20 and is free above the termination 30 (See FIG. 4) of crease 26 to bend resiliently. The bottom space 32 between base 20 and the bottom edge of shoulder supports 24 provides additional resiliency. Space 32 may also be eliminated and shoulder support 24 and base 20 connected by welding or other suitable connection process. Base 20 forms the bottom closure insert to bottom channel 40, for vent 7. (See FIG. 3). Base 20, as previously noted, may be connected to the rest of rafter bracket 10 by being a part of a continuous piece of stamped metal, welding, or other suitable connection process.
FIG. 3 illustrates the details of the mid-section of the rafter vent 5. This section consists of vent slits 34 spaced in the front section 36 (See FIG. 4) of vent 7. The lower portion 38 of the front 36 is folded behind front section 36 to form channel 40 having base 42 and turned edge 44 at the rear of vent 7. Channel 40 is of a suitable width to permit close fit of base 20 between front face 36 and edge 44 over base 42. Rolled top 46 of front face 36 forms a half cylindrical surface folded behind front section 36 to the back of vent 7 with approximately the same radius of curvature as rolled shoulders 28. This permits rolled top 46 to snap onto and fit snugly over rolled shoulders 28 of adjacent rafter brackets 10. Slits 34 are formed (See FIG. 5) by pressing protrusions 33 forward from back 37 to form a vented irregular front surface 36. Slits 34 are sized to prevent entry of birds and larger insects into the attic space.
Referring now to FIG. 4, the front partially exploded and partially assembled version of the rafter brackets 10 and vent section 7 illustrates the method of assembly of the pieces to form a rafter vent 5. Normally the procedure for installing rafter vents is to install adjacent rafter brackets 10 to rafters 1 by means of burrs 11 connected with holes 6a. The brackets 10 are located so that the lower edge of the brackets fit against the upper portion of the wall covering material, e.g., bricks 50. Thus the wall covering material may be terminated slightly below the bottom of the rafters, and the brackets and vents will cover any gap which may be left, such as between the top course of bricks 50 and the bottom of the rafters 1. This is an aid to brick masons, since it provides a tolerance so the final course does not have to terminate at the bottom of the rafter 1.
A hammer is used against ears 6 to force burrs 11 into rafters 1. Rafters 1 come down between the two ears 6 and lay on the top 22 of tongue 12 which has enough resiliency to bend down to adjust to any pitch of the roof. Additionally, because of the short length of crease 14 of tongue 12 with ears 6, problems of warpage or other distortion of rafters 1 may be avoided. Rafter brackets 10 are then secured in place to rafters 1 by nails (not shown) driven through holes 6a. Rafter brackets 10 therefore form a connection for the vent 7 with rafters 1 as well as cooperating with vent 7 to make a continuous straight surface behind which the exterior surfacing material of side 4 may be neatly terminated.
After adjacent rafter brackets 10 have been secured, vent section 7 is installed by sliding base 20 into channel 40 on each side of vent 7. Usually vent 7 is tilted out of the vertical plane so that channel 40 can engage the bases 20 on each adjacent rafter bracket 10. Then vent 7 is pushed toward the vertical plane so that rolled top 46 can snap over and engage adjacent rolled shoulders 28 on rafter bracket 10 thereby completing installation.
Standard widths and heights may be provided for both vent 7 and rafter bracket 10. Examples of these standards would be widths for 16 and 24 inch rafter spacings and heights standard for rafters 2× 4 through 2× 12 inches. Because of the ability of vent 7 to fit anywhere along rolled shoulder 28, variations of rafter spacing for standard widths and heights, either wider or narrower may be accommodated without trimming vent 7, as well as closing of openings between rafters that are out of plumb (due to warpage) without trimming vent 7.
It is also, of course, obvious that individual vents 7 may not include vent slots 34 but may in fact be solid just to close opening 3.
The components 7 and 10 of rafter vent 5 of this invention may have its parts readily stamped from a single flat sheet of aluminum or other metal sheet material and cut and bent into the shapes described for components 7 and 10, or it may be molded from various materials.
Although the device as described in detail supra has been found to be most satisfactory and preferred, different applications and many variations in its elements and the structure of its elements are, of course, possible. For example, non-standard sizes of the vent bracket 10 and vent 7 may be made using a hack saw and tin snips or otherwise stamping out the non-standard sizes. Also rafter vent brackets for inside and outside corners as needed for hip roofs, valleys and other variations may be easily formed by modifying rafter bracket 10. Moreover plastic, metal or other suitable material may be used in construction.
The above are, of course, merely exemplary of the possible changes or variations.
Because many varying and different embodiments may be made within the scope of the inventive concept herein taught, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptive requirements of the law, it should be understood that the details herein are to be interpreted as illustrative and not in a limiting sense. | An improved prefabricated apparatus used for occupying the space between the rafters, and bounded by the roofing material and the finish material on the outer walls of a building, the size of such space being dependent upon the vertical dimension of the rafter supporting the roofing material and the horizontal distance between rafters. The apparatus is provided with telescoping flexible snap-fit shoulders so that it may be adjusted for variations in the nominal (standard) spacing of rafters and rafter warpage. The apparatus is also provided with a tongue so that it may be adjusted to various rafter pitches and/or variations from the nominal (standard) rafter depth. | 5 |
TECHNICAL FIELD
This invention relates to self steering railway trucks of a type wherein the axles are allowed limited freedom to seek substantially radial positions in a curve. In preferred embodiments the invention relates to powered railway trucks for locomotives and the like, especially of the type wherein individual traction motors are supported between the frame and individual axles driven thereby.
BACKGROUND
Various types of steering railway trucks have been proposed wherein the angular position of the axles and their associated wheels are allowed or forced to adjust during curve negotiation to maintain more or less radial positions with respect to the curve. The purpose of such arrangements is, generally, to reduce friction and wear of wheels and rails by minimizing lateral creep forces. While most applications have been proposed for non-powered railway car, trucks, some locomotive applications have also been proposed.
Prior steering railway trucks have included some having soft primary suspensions which allow relatively free longitudinal and/or lateral motion of the wheel and axle assemblies within established limits. Some arrangements include inter-axle connections that require related motions among axles of the same truck. Some of the arrangements are such that lateral wheel and axle motion gives rise to forced yaw or steering, whereas other arrangements substantially isolate these functions. Both powered and unpowered axles have been arranged for steering; however, forced steering of powered axle vehicles relative to truck turning motion in relation to the carbody is common.
SUMMARY OF THE INVENTION
The present invention provides an improved arrangement for self steering railway trucks, and particularly for powered railway trucks such as in locomotives, in which equalized self steering of the axles is provided through a linkage including connected steering beams and traction rods. The mechanism is so arranged as to separate the effects of steering and lateral motions of the axles and is particularly adapted for powered truck applications where it extends around the sides and one end of the axle and frame supported traction motors.
While particularly adapted to the requirements of two axle motor powered road locomotive type railway trucks, the invention is also capable of use in unpowered trucks and in railway trucks having three or more axles where the extreme and axles are interconnected by linkage according to the invention.
In railway trucks according to the invention, traction or connecting rods extend longitudinally from journal boxes at the ends of each axle to a steering beam extending transversely and pivotally mounted at its center to the truck frame. The steering beams of the opposite end axles are preferably interconnected by a link or linkage to require equal and opposite oscillating motions of the steering beams during like steering motions of the axles. The steering beams and traction rods are preferably mounted near axle height to minimize the effect of traction forces on weight distribution.
The invention is applicable to various forms of railway trucks including powered and unpowered, having dual or other multiple axles, and with or without bolsters. However, for a further understanding of the features of the invention, reference will be had to an application of the invention in a two axle bolster type powered railway locomotive truck as illustrated in the following description and drawings in which:
BRIEF DRAWING DESCRIPTION
FIG. 1 is a side view of a two axle railway locomotive truck in accordance with the invention as installed under a locomotive carbody.
FIG. 2 is a top view of the truck from the plan indicated by line 2--2 of FIG. 1.
FIG. 3 is a longitudinal cross-sectional view through the central frame, linkage and bolster portions from the plane indicated by the line 3--3 of FIG. 2.
FIG. 4 is a transverse cross-sectional view from the plane indicated by the line 4--4 of FIG. 2.
FIG. 5 is a diagrammatic view of the interconnected axles and steering linkage showing their operating positions on tangent track, and
FIG. 6 is a diagrammatic view of the interconnected axles and steering linkage showing their operating positions on curved track.
DETAILED DESCRIPTION
In the drawings, numeral 10 generally indicates a powered self steering railway truck of the road locomotive type supporting one end of a locomotive carbody 11 shown in FIGS. 1, 3 and 4 by phantom lines. The truck 10 includes a unitary frame 12 which may be fabricated, cast or otherwise manufactured. The frame 12 includes a pair of generally parallel, laterally spaced, longitudinally extending side frames 14, 15 interconnected by a pair of transoms 16, 17, longitudinally spaced equidistant from a central transverse vertical plane 18. A central longitudinal vertical plane 19, located equidistant from the side frames 14, 15 intersects the transverse plane 18 in a central vertical axis 20.
Adjacent their ends, the truck side frames 14, 15 include downwardly extending pedestals 22 for receiving journal boxes 23 rotatably supported on the ends of axles 24 carried by rail engaging wheels 26. The wheels 26 are arranged in laterally spaced pairs connected by a single axle 24 to form longitudinally spaced wheel and axle assemblies. The journal boxes 23 are disposed in the pedestals between bearing surfaces formed by pedestal liners 27 or other suitable pedestal bearing surfaces. A small amount of longitudinal clearance is provided to allow for limited longitudinal motion of the journal boxes relative to the truck frame for steering of the wheel and axle assemblies in a manner to be subsequently described.
Lateral stops, not shown, are provided between the journal boxes and the truck frame to limit lateral motion of the wheel and axle assemblies to a predetermined amount. The truck frame is supported on the journal boxes by a relatively soft primary suspension comprising coil springs 28 for which rubber or other suitable alternative resilient suspension means or devices could be substituted.
Centrally of the truck, a transverse bolster 30 is carried within a space bounded by the side frames 14, 15 and transoms 16, 17. The bolster is supported upon the truck frame by a relatively stiff secondary suspension comprising, but not limited to, rubber sandwich elements 31. Front and rear bearing plates 32 are provided between the bolster and transoms which substantially limit movement of the bolster to lateral and vertical motions relative to the truck frame and transfer longitudinal traction and braking forces between the bolster and truck frame. A center bearing 34 is provided at the center of the bolster for pivotally connecting the truck with a downward projection 35 of the carbody.
For powering the wheel and axle assemblies to drive the locomotive, the truck is provided with a pair of traction motors 36. Each motor has an outer end 37 supported by conventional bearing means on one of the axles 24, and an inner end 38 carried from the adjacent transoms 16, 17 by a depending link 39. The link is flexibly or swivelly connected at its ends to allow a limited amount of both longitudinal and lateral motion between the inner end of the traction motor and the adjacent transom member from which it is supported.
To provide for limited self-steering action of the wheel and axle assemblies in accordance with the invention, while transmitting traction and braking forces between the wheel and axle assemblies and the truck frame, the truck is provided with suitable traction linkage. This linkage includes a pair of lateral steering beams 40 pivotally connected at their centers with the truck frame and each connected at their ends with the journal boxes of one of the wheel and axle assemblies by connecting rods, or traction rods, 42. The traction rod connections are preferably by means of rubber bushings, spherical connections or other movable joints to permit relative vertical motion between the steering beams and their connected journal boxes.
The central pivotal mounting of the steering beams 40 is provided by upper and lower support plates 43, 44 of a support structure carried below the transoms 16, 17 of the truck frame and carrying pivot pins 46, 47 on which the front and rear steering beams 40 are respectively pivotally carried. The pivot pins 46, 47 are vertically disposed along the central longitudinal plane 19 of the truck and spaced equidistant from the vertical central axis 20, just inwardly of the transoms 16, 17.
The steering beams 40 are, in turn, interconnected for substantially equal and opposite pivotal motions. For this purpose, a link 48, connects laterally offset forward and rearward extensions 50, 51 of the rear and front steering beams 40, respectively, through pin and bushing connections 52, 53.
Braking action for the truck may be provided for in any suitable manner. The illustrated embodiment includes more or less conventional brake rigging, including wheel engaging brake shoes 55 carried by conventional frame supported brake rigging 56 actuated by truck frame supported air brake cylinders 58. If desired, vertical motions of the truck frame with respect to the wheel and axle assemblies may be damped in conventional manner by friction or hydraulic damping devices 59 connected between the truck frame and one or more of the axle carried journal boxes 23.
For the purposes of carrying out the invention, the traction linkage comprising the steering beams and connecting rods are preferably disposed near axle height. The traction rods extend forward in the parallel, generally horizontal orientation from the journal boxes at the ends of the axles toward the central plane 18 of the truck. There they connect with the steering beams to define a linkage passing essentially around three sides of the traction motors, so as to avoid extending through or otherwise impinging upon the space provided for the traction motors and the brake linkage adjacent the truck wheels. Also, if desired, the wheel treads may be formed with a higher than normal taper to encourage self-steering action, although this is not necessarily a requirement of the present design, which permits self-steering action to occur even with the normal wheel tread taper conventionally provided for locomotive trucks.
In operation, normal pivotal action of the truck with respect to the railway carbody is provided by the center bearing connection between the truck and carbody. Such action could alternatively be provided by bolsterless suspension means or other support means known in the art. Also in known manner, the clearance provided between the pedestals 22 and their associated journal boxes 23 permits relative longitudinal motion of the axles within the truck frame so as to allow self-steering of the wheel and axle assemblies within the truck frame. Such action is known in the art to allow the axle members of conventionally or more highly tapered wheel and axle assemblies, of the flanged rail engaging type herein considered, to seek more or less radial positions during curving action of a railway vehicle.
Such self-steering action of the wheel and axle assemblies is known to reduce friction and wear between the wheels and rails and, in powered trucks, has been found to provide more efficient application of tractive effort and to reduce traction-limiting wheel slippage during curving action. However, unrestrained self-steering action of the axles may have the effect of reducing stability of a railway truck in an unacceptable degree. This is avoided in the present instance by the interconnection, through the nearly transverse link 48, of the steering beams 40, which limits the pivotal motion of the steering beams to substantially equal and opposite oscillating motion. This, in turn, limits the turning motions of the connected wheel and axle assemblies to like equal and opposite oscillating motions so that self-steering action is allowed, but only to the extent that the turning motions of the axles are in equal and opposite amounts, all within the limits provided by clearances between the truck pedestals and journal boxes.
Traction and braking forces are also carried from the wheel and axle assemblies to the truck frame through the traction linkage consisting of the traction links 42 and the steering beams 40. Thus, all traction and braking loads are carried through the pivot pins 46, 47 to the truck frame and from the truck frame through the bearing plates 32 to the bolster 30 where they pass through the center bearing 34 to the carbody 11.
Because of the parallel and longitudinal orientation of the traction rods, the application of traction and braking forces does not create any side thrust forces on the wheel and axle assemblies. Also, lateral motion of the axles relative to the truck frame, allowed within desired limits to accommodate track variations and other side thrust loads, do not introduce any yaw, or steering, component of force into the system, as is the case with diagonally interconnected axles commonly provided. Thus, with the present invention complete separation of yaw and lateral motions of the truck axles is maintained.
While the invention has been disclosed by reference to a particular embodiment chosen for purposes of illustration, it should be understood that the self-steering and other features of the present invention and the forms of trucks to which they are applied could be modified without departing from the spirit and scope of the novel concepts described. Accordingly, it is intended that the invention not be limited to the described embodiment, but that it have the full scope permitted by the language of the following claims. | A self steering railway truck, especially a powered locomotive type, provides limited freedom for axle steering motion in the truck frame with a separate linkage of parallel rods and a steering beam for transmitting traction and braking forces to the truck frame. The linkages of two end axles are interconnected for equal and opposite motion to maintain stability and leave room for maintaining traction motors and brake equipment as well as separating effects from yaw and lateral axle motions. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a U.S. National Stage Application of International Application No. PCT/EP2008/004774 filed Jun. 13, 2008. The contents of which are hereby incorporated by reference in their entirety.
TECHNICAL FIELD
[0002] The invention relates to a system and a feed-in electricity meter for manipulation-protected detection of an amount of feed-in electricity.
BACKGROUND
[0003] A growing number of households are installing equipment for supplying their own electricity locally, e.g. for economical or ecological reasons. If a household generates more electricity than it requires for its own use, it can feed the surplus amount of electricity into the electrical grid.
[0004] In its simplest form, this feed-in energy is measured by a conventional electricity meter, which runs backwards during the time when electricity is being fed into the electrical grid. During this time, the recorded energy consumption of the household is reduced by the amount of feed-in electricity. There are also electricity meters which can measure the amount of consumed electricity and the amount of feed-in electricity separately.
[0005] Provided suitable technical arrangements are made (e.g. grid synchronization), it is therefore fundamentally possible to feed locally produced electricity into the networks of energy supply companies when the local electricity production exceeds the local electricity requirement.
[0006] Renewable energies are typically converted into electrical power for this purpose, e.g. in the form of a photovoltaic or solar power system on the outside or roof of the house, a biogas power system or a wind power system. In order to encourage investment in corresponding systems, the payments for feed-in electricity are subsidized, so that comparatively high levels of remuneration can be claimed for the feed-in electricity. This is governed by the Renewable Energy Law (EEG) in Germany, for example.
[0007] Consequently, there is a considerable incentive to manipulate electricity meters for measuring the amount of feed-in electricity. For example, electricity that was not generated using renewable energies, but was obtained relatively cheaply via a public electricity supply grid, is fed into the grid for this purpose. An attempt is thus made to receive a high subsidized payment for the energy that is fed in.
[0008] Electricity meters today are protected against manipulation, in order to ensure that the amount of electricity detected by the electricity meter corresponds to the amount of electricity that is actually consumed or fed in. If the measured data is queried remotely (remote metering), the communication between electricity meter and query system of the energy supply company can be cryptographically protected. However, this does not prevent electricity that was obtained in a conventional manner from being fed in (and hence measured) by a user with fraudulent intention.
SUMMARY
[0009] According to various embodiments, a system for manipulation-protected detection of an amount of feed-in electricity can be specified, in which it is possible to reconstruct a balance between the amount of electricity that is generated and that which is fed in.
[0010] According to an embodiment, a system for manipulation-protected detection of an amount of feed-in electricity, may comprise at least one electricity generating unit which features an integrated electricity meter for detecting an amount of electricity that is generated by the electricity generating unit, a feed-in electricity meter for detecting an amount of electricity that is fed in by the electricity generating unit, a transmission entity for transferring information about the detected generated amount of electricity to the feed-in electricity meter, wherein a manipulation-protected amount of feed-in electricity is determined by the feed-in electricity meter, in accordance with predefinable criteria, from the detected amount of generated electricity and the detected amount of feed-in electricity.
[0011] According to a further embodiment, the feed-in electricity meter can be read by a network operator via a remote query, information about the detected amount of generated electricity and the detected amount of feed-in electricity can be determined at the network operator in the context of the readout. According to a further embodiment, for the purpose of determining the manipulation-protected amount of feed-in electricity, the detected amount of generated electricity and the detected amount of feed-in electricity can be compared, taking into consideration any losses during energy transfer from the electricity generating unit to the feed-in electricity meter, and the detected amount of feed-in electricity can be corrected or controlled accordingly. According to a further embodiment, the information concerning the detected amount of generated electricity can be transferred by cryptographically protected means. According to a further embodiment, information for authenticating the electricity generating unit can be additionally transferred from the transfer entity to the feed-in electricity meter, the information authentication of the electricity generating unit is checked by the feed-in electricity meter. According to a further embodiment the transfer of information concerning the detected amount of generated electricity can be effected using wire-based means, in particular via Power Line Communication (PLC), or wirelessly. According to a further embodiment, an inverter unit can be provided for generating an alternating current from a direct current that is generated by the electricity generating entity.
[0012] According to another embodiment, a feed-in electricity meter for manipulation-protected detection of an amount of feed-in electricity, may comprise an entity for detecting an amount of electricity that is fed in from an electricity generating unit, a communication entity for receiving information concerning a generated amount of feed-in electricity from the electricity generating unit, wherein the feed-in electricity meter is configured to determine a manipulation-protected amount of feed-in electricity, in accordance with predefinable criteria, from the received amount of generated electricity and the detected amount of feed-in electricity.
[0013] According to a further embodiment of the feed-in electricity meter, the feed-in electricity meter can be configured for remote query by a network operator.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The present invention is explained in greater detail below on the basis of exemplary embodiments and with reference to the figures, in which:
[0015] FIG. 1 shows a schematic illustration of a possible embodiment of the system for manipulation-protected detection of an amount of feed-in electricity,
[0016] FIG. 2 shows a schematic illustration of a further possible embodiment of the system for manipulation-protected detection of an amount of feed-in electricity.
DETAILED DESCRIPTION
[0017] According to various embodiments, a system for manipulation-protected detection of an amount of feed-in electricity comprises at least one electricity generating unit which features an integrated electricity meter for detecting an amount of electricity that is generated by the electricity generating unit. Furthermore, the system features a feed-in electricity meter for detecting an amount of electricity that is fed in by the electricity generating unit and a transmission entity for transferring information about the detected generated amount of electricity to the feed-in electricity meter. The feed-in electricity meter is configured in such a way that a manipulation-protected amount of feed-in electricity is determined, in accordance with predefinable criteria, from the received amount of generated electricity and the detected amount of feed-in electricity.
[0018] In order to prevent manipulation, the various embodiments provide for electricity meters which detect the amount of generated electricity to be integrated decentrally in the individual photovoltaic modules, for example. This information is then transferred to the centrally arranged feed-in electricity meter, such that a comparison can be made between an amount of feed-in electricity and an actual amount of generated electricity. Thus it is advantageously ensured that the electricity which has actually been generated in a subsidized way can be determined proportionally from the amount of feed-in electricity.
[0019] According to an embodiment, the feed-in electricity meter can be read remotely by a network operator via a remote query, wherein information about the detected amount of generated electricity and the detected amount of feed-in electricity are transmitted to the network operator in the context of the readout. In this way, the analysis can be performed by the network operator to whom the feed-in electricity is supplied. As part of this activity, provision can also be made for additionally transmitting a warning report, for example.
[0020] According to an embodiment, for the purpose of determining the manipulation-protected amount of feed-in electricity, the feed-in electricity meter compares the detected amounts of generated and feed-in electricity, taking into consideration any losses resulting from energy transfer, and corrects the detected amount of feed-in electricity accordingly. A consistency check between the amount of generated energy and the amount of feed-in energy is therefore advantageously performed. The efficiency or losses due to the energy transfer from the electricity generating unit to the feed-in electricity meter are taken into consideration in the context of such a consistency check. For example, a percentage reduction is therefore applied such that, in the case of an amount of generated electricity of 127 kWh and an efficiency of 80%, the detected amount of generated electricity is 127 kWh·0.8=101.6 kWh.
[0021] On the basis of this information, it is possible e.g. to limit the amount of feed-in electricity to the amount of electricity that is verifiably generated by photovoltaic modules. Further elements between the electricity generating units and the feed-in electricity meter, such as e.g. an inverter, result in further losses and can be taken into consideration accordingly when determining the detected amount of generated electricity.
[0022] According to a further embodiment, information for authenticating the electricity generating unit is additionally transferred from the transfer entity to the feed-in electricity meter, and the information for authenticating the electricity generating unit is checked by the feed-in electricity meter. In this way, a relationship is advantageously established between the individual electricity generating units and the feed-in electricity meter. The identities of the solar modules in a household can be entered in a list, for example. Only measured data that is received from the listed solar modules is then accepted. This can be managed via a protected administration interface, for example. The energy supply company, with which a feed-in contract has been agreed and which operates the feed-in electricity meter, can therefore configure the feed-in electricity meter in such a way that it only accepts and analyzes measured data from the configured solar modules, for example.
[0023] The feed-in electricity meter according to various embodiments for manipulation-protected detection of an amount of feed-in electricity features an entity for detecting an amount of feed-in electricity from an electricity generating unit and a communication entity for receiving information about a generated amount of feed-in electricity from the electricity generating unit. The feed-in electricity meter is configured such that, in accordance with predefinable criteria, a manipulation-protected amount of feed-in electricity can be determined from the received amount of generated electricity and the detected amount of feed-in electricity.
[0024] FIG. 1 shows a photovoltaic module 101 comprising a plurality of solar cells 102 . The photovoltaic module 101 transfers the generated energy to the exterior via two electricity lines 103 .
[0025] In addition, the photovoltaic module 101 has an integrated electricity meter 104 , by means of which the amount of generated electricity is detected and stored.
[0026] In addition, the photovoltaic module 101 features a communication module 105 , via which it is possible to query the current value of the amount of electricity, as measured by the integrated electricity meter 104 .
[0027] Optionally or additionally, provision can also be made for a display device, on which the detected amount of electricity is displayed.
[0028] The communication takes place via a separate interface, e.g. serially (RS232, USB) or wirelessly (IEEE 802.15.4, ZigBee, WLAN). In an embodiment, the communication takes place via Power Line Communication, i.e. via electricity lines.
[0029] The electricity meter 104 preferably stores an identifier of the photovoltaic module 101 , e.g. a serial number, and a cryptographic key. The cryptographic key is e.g. a symmetrical key for a symmetrical cryptographic method or a private key for an asymmetrical cryptographic method. The information that is provided in relation to the detected amount of generated electricity can then be additionally protected against manipulation by a cryptographic checksum (Message Authentication Code, digital signature).
[0030] The electricity that is generated by the photovoltaic module is fed into the electricity grid 207 of an energy supply company via a feed-in electricity meter 106 .
[0031] Using Power Line Communication, information about the detected amount of generated electricity and an identifier of the photovoltaic module 101 are also transferred to the feed-in electricity meter 106 via the electricity lines 103 .
[0032] The feed-in electricity meter 106 first checks the identity of the photovoltaic module 101 , e.g. by means of comparison with a list of authorized photovoltaic modules. Measured data is only accepted from authorized photovoltaic modules. A received cryptographic checksum can be checked using the stored cryptographic key which is assigned to the photovoltaic module (symmetrical key for a symmetrical method, public key for an asymmetrical method). After successful checking, the electricity that was actually generated in a subsidized way is determined proportionally by the electricity meter 106 from the total amount of feed-in electricity, by comparing a detected amount of generated electricity and a detected amount of feed-in electricity.
[0033] FIG. 2 shows an installation comprising four photovoltaic modules 201 to 204 , each of which is configured as per FIG. 1 .
[0034] The energy that is generated by the four photovoltaic modules 201 to 204 is routed to an A.C. current converter 205 . This generates an alternating current, which is suitable for feeding into the grid of an energy supply company, from the direct current that is generated by the four photovoltaic modules 201 to 204 .
[0035] The alternating current that is generated by the A.C current converter 205 is now fed into the electricity grid 207 of an energy supply company via an electricity meter 206 .
[0036] The feed-in electricity meter 206 according to various embodiments is configured to receive the information transmitted from the communication module 105 of a photovoltaic module 201 to 204 concerning the detected amount of generated electricity.
[0037] If a consistency check is now required, for example, the electricity meter 206 can read out the current values for the amount of electricity from the photovoltaic modules 201 to 204 , and compare them with the measured amount of feed-in electricity. Consideration is preferably given to the efficiency of the overall installation in this context, i.e. to the respective energy losses that occur in the photovoltaic modules 201 to 204 and the energy losses that occur in the A.C. current converter 205 , for example.
[0038] According to an embodiment, the feeding in of electricity is stopped by the feed-in electricity meter 206 when the verifiably generated amount of electricity has already been fed in.
[0039] Alternatively, the consistency check can also be performed by the network operator, i.e. by transmitting the information about the detected amount of generated electricity and about the detected amount of feed-in electricity to the network operator.
[0040] In an alternative embodiment, the inverter 205 receives the information from the respective communication module 105 of a photovoltaic module 201 to 204 concerning the detected amount of generated electricity, measures the amount of electricity that has been supplied, and performs a consistency check by comparing the information with the measured amount of electricity that has been supplied. The inverter can additionally feature a communication module (not shown), by means of which it transfers information to the feed-in electricity meter 206 . This information can be the result of a consistency check, or information which is aggregated from the information that has been transmitted by the respective communication module 105 of the photovoltaic modules 201 to 204 , e.g. the total of the respective values of the amount of electricity, optionally reduced by energy losses that occur during the transfer of electricity and/or in the inverter 205 . | Many households are increasingly installing systems for their own electricity supply from renewable energies, for example for economical or ecological reasons. If a household produces more electricity than it needs for its own use, it can feed the surplus amount of power into the electrical grid. In order to promote investment in corresponding systems, the payments for the power fed in are subsidized in many countries, with the result that comparatively high remuneration can be paid for the power fed in. Consequently, there is a great incentive to manipulate electricity meters for measuring the amount of power fed in. Hence, a system for detecting the amount of power fed in in a manner which is protected against manipulation can be provided, in which system the amount of power actually produced and that fed in can be balanced. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to a high speed image drawing method permitting the drawing of an image including curves in an image output region at a high speed and with a visually more natural appearance, and to an apparatus for realizing the method.
In the case where a raster scan type CRT display is used as a graphic terminal for a computer system, it is usual to draw an image on the screen by illuminating selectively desired pixels on the screen, in the case of an image output region composed of a plurality of pixels arranged in a matrix form. Further, a plasma display or a display consisting of light emitting diodes arranged in a matrix form is a typical image output apparatus constituted by pixels arranged in a matrix form, for each of which a light emitting element operates as a pixel.
When a desired image is drawn on such an image output apparatus composed of pixels arranged in a matrix form, any image drawn in the image output region cannot be represented by a smooth curve. For example, when the image to be drawn is an ellipse 1 as indicated in FIG. 1A, the image 3 actually drawn in the image output region composed of pixels arranged in a matrix is an approximate image composed of a set of segments, as indicated by 2 in FIG. 1B.
Heretofore, in the case where an image was displayed in an image output region composed of pixels arranged in a matrix form, since pixels to be illuminated were selected by calculating for each of the pixels which was the closest pixel in the image output region to the image to be drawn, the time necessary for the drawing was long. For example, as seen in FIG. 2 suppose that it is to be determined which pixel after a pixel P o is to be illuminated, when an image S represented by a function F(x, y)=0 is being drawn in the direction indicated by the arrow. According to one of the methods proposed heretofore, at first 8 pixels P 1 , P 2 , . . . , P 8 adjacent to the pixel P o in the up and down directions, and right and left directions are selected as candidates for the pixel which is to be illuminated next. Then the pixels P 4 , . . . , P 8 are excluded, by considering the inclination of the image S to be drawn and the direction of the advance of the drawing. After that, for each of the remaining 3 candidate pixels P 1 , P 2 and P 3 , the distance therefrom to the image S to be drawn, which is represented by the function F(x, y)=0, is calculated and the pixel having the smallest distance is selected as the pixel, which is to be illuminated next. Since a number of calculations should be repeated for each of the pixels in this way, a long time is necessary for producing the drawing in this way.
Further, according to the prior art method described above, since the pixel to be illuminated was determined only on the basis of calculation results, sometimes visually unnatural parts appeared in the image drawn in the image output region or on the display screen. For example, according to the prior art method, it happened that the pixels indicated in FIG. 3A were selected so as to be illuminated for the image to be drawn. However, when an observer looks at the image screen, on which such an image is drawn, since the part indicated by Q in FIG. 3A has a higher pixel density than the others, it looks like a protuberance-like lump attached on a curve so that the observer finds it ugly. It was found that if the pixels to be illuminated are selected as indicated in FIG. 3B for the same image as that for FIG. 3A, the observer finds it more natural.
SUMMARY OF THE INVENTION
This invention is directed to solution of the problematical points of the prior art, as described above, and its object is to provide a high speed image drawing method which makes it possible to draw an image including curves in an image output region at a high speed and with a visually more natural appearance, and an apparatus for realizing it.
This invention is characterized in that when segments are drawn in the image output region, the direction of the drawing is restricted to several predetermined drawing directions (e.g. 2 directions, i.e. X- and Y-axis directions in an orthogonal X-Y coordinate system), that a segment is drawn while selecting one of the predetermined directions, depending on the inclination of the tangent of the image to be drawn at each point and that the image is drawn by repeating this procedure. In this specification, a segment consisting only of one pixel is also referred to as a segment.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B are schematic diagrams for explaining the difference between an image to be drawn and an image which is actually drawn in the image output region;
FIG. 2 is a schematic diagram for explaining a prior art drawing method;
FIG. 3A is a schematic diagram for explaining problematical points in an image drawn according to the prior art method; and FIG. 3B is a schematic diagram illustrating an example of images drawn to appear visually more naturally;
FIG. 4 is a schematical view illustrating a display device used for realizing this invention;
FIGS. 5A, 5B and 5C shows three different images to be drawn by using the display device illustrated in FIG. 4;
FIG. 6 is a block diagram indicating a concrete example of the construction of the display device illustrated in FIG. 4;
FIG. 7 is a flow chart showing the procedure for the drawing of images by using the display device illustrated in FIG. 4;
FIG. 8 is a flow chart showing a subroutine procedure for drawing each of the images in the flow chart in FIG. 7;
FIG. 9 is a flow chart showing a subroutine procedure for drawing segments in the flow chart in FIG. 7;
FIG. 10 is a flow chart showing a subroutine procedure for drawing segments constituting an ellipse;
FIG. 11 is a flow chart showing the procedure for drawing vertical segments in the flow chart in FIG. 10;
FIG. 12 is a flow chart showing the procedure for drawing horizontal segments in the flow chart in FIG. 10;
FIG. 13 is a graph for explaining the method for drawing vertical segments, taking an ellipse as an example, according to this invention;
FIGS. 14A and 14B are a scheme for explaining a write-in operation for image data indicating pixels to be drawn to an image buffer;
FIGS. 15A and 15B indicate graphs showing examples of images drawn according to the image drawing method of this invention; and
FIG. 16 is a graph showing a variation of the image drawing method according to this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinbelow some preferred embodiments of this invention will be explained, referring to the drawings.
FIG. 4 illustrates the outline of a display device, which is an embodiment of this invention. As indicated in the figure, the display device comprises a key board 201 and a CRT display portion 202, and a cursor shifting key 203, a cursor position coordinate input key 204, a straight line drawing command key 205, an ellipse drawing command key 206 and a circle drawing command key 207 are disposed on the key board 201.
In the case where a straight line as indicated in FIG. 5A is to be drawn, at first the straight line drawing command key 205 is pushed. Then, the cursor is set at the position A corresponding to an end of the straight line on the CRT display portion 202 by using the cursor shifting key 203 and the cursor position coordinate input key 204 is pushed. Further, the cursor is set at the position B corresponding to the other end of the straight line and the cursor position coordinate input key 204 is pushed. The desired straight line is displayed by the procedure described above.
Next, in the case where an ellipse as indicated in FIG. 5B is to be drawn, at first the ellipe drawing command key 206 is pushed. Then, the cursor is set at the position A corresponding to the center of the ellipse on the CRT display portion 202 by using the cursor shifting key 203 and the cursor position coordinate input key 204 is pushed. Further, the cursor is set at a position B, which is spaced from the center of the ellipse by the length of the major axis, by using the cursor shifting key 203 and the cursor position coordinate input key 204 is pushed. After that, the cursor is set at a position C, which is spaced from the center of the ellipse by the length of the minor axis, by using the cursor shifting key 203 and the cursor position coordinate input key 204 is pushed. By the procedure described above, the ellipse is displayed.
In order to display a circle as indicated in FIG. 5C, the circle drawing command key 207 is pushed. Then, the cursor is set at a position A corresponding to the center of the circle and the cursor position coordinate input key 204 is pushed. Further, the cursor is set at a position B, which is apart from the center of the circle by the length of the radius and the cursor position coordinate input key 204 is pushed. By the procedure described above, the circle is displayed.
FIG. 6 is a block diagram indicating an example of devices for realizing the high speed drawing method according to this invention. When either one of the straight line drawing command key 205, the ellipse drawing command key 206 and the circle drawing command key 207 disposed on the key boards 601 is pushed, a code is produced by a keyboard driver 602, which code is stored in a register 603 and a CPU 604 starts the program in a memory device 605. Registers 609, 610 and 611 constitute a group of registers for storing parameters of the image to be drawn. The cursor position information in the CRT display portion 606 is stored in a cursor register 608 by a CRT driver 607.
In the case where the pushed key is the straight line drawing command key 205, when the cursor position coordinate input key 204 is pushed, the CPU 604 stores the coordinates of the position of an end of the straight line from the cursor register 608 where the position of the cursor is stored in the register A 609 and those coordinates of the other end in the register B 610. After that, it effects processing to write the straight line on an image screen buffer. Since each of the memory cell positions in the image screen buffer 612 corresponds to each of the pixels on the image screen of the CRT display device, e.g. when "1" is written in a memory cell position in the image screen buffer 612, the pixel on the image screen of the CRT display device corresponding to the memory cell position is illuminated.
In the case where the pushed key is the ellipse drawing command key 206, when the cursor position coordinate input key 204 is pushed, the CPU 604 stores the coordinates of the position of the center of the ellipse in the register A 609, the length of the major axis in the register B 610 and the length of the minor axis in the register C 611 from the cursor register 608 where the position of the cursor is stored. After that, it effects processing to write the ellipse on the image screen buffer.
In the case where the pushed key is the circle drawing command key 207, when the cursor position coordinate input key 204 is pushed, the CPU 604 stores the coordinates of the position of the center of the circle in the register A 609 and the length of the radius in the register B 610 from the cursor register 608 where the position of the cursor is stored. After that, it effects processing to write the circle on the image screen buffer.
Next, the whole procedure for drawing an image on the display device indicated in FIG. 4 will be explained, by referring to FIG. 7.
At first, in Step 701, an image command indicating the nature of the image to be drawn is inputted, which command is produced by pushing either one of the keys 205, 206 and 207. However, this image command is not limited to those inputted by the keys 205-207 pushed by the operator, but for example, the program can be so modified that the image command is spontaneously produced as an execution command for the program in the course of the execution of the program carried out in the drawing device. Next, in Step 702, the command code of the inputted image command is identified and the command is directed to the straight line drawing subroutine (Step 703), the ellipse drawing subroutine (Step 704) or the circle drawing subroutine (Step 705), depending on the value of the code.
Any of the drawing subroutines in Steps 703, 704 and 705 effects similar treatment, the general flow of which is indicated in FIG. 8. In FIG. 8, the parameters of the image to be drawn (e.g. for an ellipse, the position of the center, the length of the major axis, the length of the minor axis, etc. of the ellipse in the image output region or on the display screen) are inputted in Step 801. In the display device indicated in FIG. 4, the parameters of the image are inputted by the operator, specifying them by the shift of the cursor, but just as for the input of the image command, the program can be so modified that the parameters of the image are produced as an execution command for the program in the course of the execution of the program carried out in the drawing device.
Next, in Step 802, a function F(x, y)=0 representing the image to be drawn is determined on the basis of the parameters of the image inputted in Step 801. Further, in Step 803, coordinates (X, Y) are obtained for particular points having particular inclinations (e.g. points, where the tangent of the tangential line is equal to +1 or -1) among inclinations of the tangential line at each point of the image by using the function representing the image and stored in a register. In Step 804, the straight line drawing subroutine is carried out by using the coordinates (X, Y) of these particular points.
FIG. 9 shows the general aspect of the treatment according to the straight line drawing subroutine. In Step 901, it is judged if the tangent of the tangential line at the point corresponding to the segment drawing starting pixel (which is the drawing starting pixel of the image for the first segment to be drawn) is greater or smaller than the particular tangents (in this example ±1). In practice, if the coordinates (X, Y) of the particular points obtained referring to FIG. 8 are known, it is not necessary to examine the tangent of the tangential line at all the points of the image to be drawn, because every point of the image between the particular points has the same relation with respect to the comparison of the tangent as at one of the particular points.
If, in Step 901, the tangent α of the tangential line at a point of the image is -1≦α<1, proceed to Step 904, where the length of a segment to be drawn in the direction parallel to the X-axis, seen on the image output region or the display screen, (i.e. the number of pixels constituting the segment) is determined. In this embodiment, since it is supposed that the interval between the pixels is equal to 1, in Step 904, when the image is drawn in a direction that the Y-coordinate of the image is increased, a straight line parallel to the X-axis and passing through a point (0, Y+1/2) is chosen as an auxiliary line for determining the length of the segment and when the image is drawn in a direction that the Y-coordinate of the image is decreased, a straight line parallel to the X-axis and passing through a point (0, Y-1/2) is chosen as an auxiliary line. The intersection of one of these straight lines parallel to the X-axis with the image to be drawn is calculated and the value X 1 of the X-coordinate of the pixel, which doesn't exceed the X-coordinate of the intersection and is the closest to it, is obtained, because the coordinates (X, Y) of the pixels constituting the pixel matrix are not continuous but separate from each other.
In this way, the length of the segment extending from the segment drawing starting pixel, which is at the coordinates (X, Y), to the segment drawing ending pixel, which is at the coordinates (X 1 , Y) in the direction parallel to the X-axis is determined and in Step 905, the segment is drawn. In practice, the CPU 604 in FIG. 6 transmits image data indicating pixels constituting the segment to be drawn (i.e., pixels to be illuminated on the display screen) to a bit map processor 620. Another bit map processor 620 receives this image data and writes a determined bit, e.g. "1", in a corresponding memory cell position of an image screen buffer 612. A video control device 621 reads-out the data in the image screen buffer 612 at a high speed and drives a CRT 606 according to the data thus read-out. In this way, an image corresponding to the content of the image screen buffer 612 is displayed on the display screen.
If, in Step 901, the tangent α of the tangential line at the point of the image is α<-1 or 1≦α, proceed to Step 902, where the length of a segment to be drawn in the direction parallel to the Y-axis, seen on the image output region or the display screen, is determined in the same way as in Step 904. However, in Step 902, if the image is drawn in a direction that the X-coordinate of the image is increased, a straight line parallel to the Y-axis and passing through a point (X+1/2, 0) is chosen as an auxiliary line for determining the length of the segment and if the image is drawn in a direction that the X-coordinate of the image is decreased, a straight line parallel to the Y-axis and passing through a point (X-1/2, 0) is chosen as an auxiliary line. By using the intersection of one of these straight lines parallel to the Y-axis with the image to the drawn, the value Y 1 of the Y-coordinate of the pixel, which doesn't exceed the Y-coordinate of the intersection and is closest to it, is obtained.
In Step 903, a segment extending from the segment drawing starting pixel (X, Y) to the segment drawing ending pixel (X, Y 1 ) in the direction parallel to the Y-axis is drawn.
When the drawing of the segment is terminated is Step 903 or 905, it is judged if it is necessary to continue to draw the image or not. More particularly, it is determined if the segment drawing ending pixel of the segment, which has been drawn in Step 903 or 905, is the drawing ending pixel of the image. If it is necessary to continue to draw the image, proceed to Step 909, where the segment drawing starting pixel of the following segment to be drawn is chosen. For example, when the tangent or inclination α of the tangential line of the image described above is 0<α<π/2 and the image is drawn in a direction that its X-coordinate is increased (that is, its Y-coordinate is also increased), supposing that the coordinates of the segment drawing ending pixel of the segment, which have been determined immediately before are (X e , Y e ) and that the interval between the pixels in the directions of the X- and Y-axes is 1, the pixel whose coordinates are (X e +1, Y e +1) is the segment drawing starting pixel of the following segment to be drawn. In the same way, when -π/2<α<0 and the image is drawn in a direction that its X-coordinate is increased (that is, its Y-coordinate is decreased), the pixel at the coordinates (X e +1, Y e -1) is the segment drawing starting pixel of the following segment to be drawn.
After having repeated segment drawings in this way, when it is judged in Step 908 that it is no longer necessary to draw the image, the drawing of the image is terminated.
A method for drawing 1/4 of an ellipse will be explained below more in detail, referring to FIG. 10 to FIG. 13. When 1/4 of an ellipse is drawn, it is evident that it is possible to draw a whole ellipse by rotating the partial curve and turning it upside down in a suitable manner.
FIG. 10 is a flow chart showing the whole treatment for drawing 1/4 of an ellipse S, as indicated in FIG. 13. Suppose that the coordinates of the segment drawing starting pixel are (sx, sy) and that the coordinates of the segment drawing ending pixel are (ex, ey). Since the drawing is started at the origin (0, 0) in FIG. 13, 0 is set at registers corresponding to sx, sy in Step 100. Futher, since the drawing begins with the length of the segment (i.e. the number of pixels) equal to the length of a single pixel (i.e. 1), 0, which is the same value as sy, is set at a register corresponding to ey. In FIG. 13, the X-coordinate Xq of a particular point, where the tangent α of the tangential line of the ellipse S to be drawn is 1, can be obtained by using a function representing the ellipse S. Consequently, the part of the image in the region 0≦x<Xq is drawn with a set of vertical segments in Step 101. When the drawing in Step 101 is terminated, the values of the segment drawing ending pixel are initialized in Step 102 in order to prepare for the drawing of segments in the horizontal direction. After that, in Step 103, the part of the image in the region Xq≦x<Xr (i.e., the region Yq≦y<Yr) is drawn with a set of horizontal segments.
FIG. 11 shows the segment drawing subroutine treatment of the vertical segments in FIG. 10 in detail. In FIG. 13, the coordinates of the first segment drawing starting pixel are (0, 0). Consequently, a condition sx<Xq is valid. Thus the judgment in Step 110 is "NO" and the procedure proceeds to Step 111. In Step 111, considering a point C 1 , whose coordinates are (1/2, 1), advanced from the segment drawing starting pixel in the positive direction along the X-axis by 1/2 of the interval between the pixels (1/2 in this case) and in the positive direction along the Y-axis by +1, it is judged if this point C 1 has traversed the image of the ellipse S or not. This judgment can be effected by substituting the values of the coordinates of the point C 1 for x and y in the function F(x, y) representing the image and examining if F(1/2, 1)≦0 is valid. Since F(1/2, 1)<0 is valid in Step 111, the procedure proceeds to Step 112 and after having increased ey by +1, returns to Step 110. When the procedure proceeds secondly to Step 111, since ey is increased by +1, it is judged if the point C 2 (1/2, 2) in FIG. 13 has traversed the image of the ellipse S or not. Similarly to the case of the point C 1 , since F(1/2, 2)<0 is valid, the procedure proceeds to Step 112 ey is further increased by +1 and returns to step 110. By repeating such a loop for the points from C 1 to C 4 , 4 is set in the register corresponding to ey in Step 112 and the procedure returns to Step 110. Then, the procedure proceeds from Step 110 to Step 111. In Step 111, it is judged if the point C 5 (1/2, 5) has traversed the image of the ellipse S or not. Since F(1/2, 5)>0, the procedure proceeds to Step 113, where a segment extending in the vertical direction and having a length from the segment drawing starting point, whose coordinates are (0, 0), to the segment drawing ending point, whose coordinates are (0, 4), is drawn. In practice, as already mentioned, the data showing the pixels constituting the segments are written in the image screen buffer 612 in FIG. 6. When the drawing of the segment is terminated, the procedure proceeds to Step 114. In Step 114, 1, 5 and 5 are set in the registers corresponding to sx, sy and ey, respectively. The pixel P s2 of coordinates (1, 5) is the segment drawing starting pixel of the following segment. It is for initializing the values of the segment drawing ending pixel at the moment, where the decision of the length of the segment is begun, that 5, which is the same as for sy, is set in ey. In addition, when the first segment is drawn, it can be seen that the points C 1 to C 5 are aligned on a straight line LA parallel to the Y-axis and passing through a point of coordinates (0, 1/2) (which can be called an auxiliary line for determining the length of the segment). Further, since the segment drawing starting pixel P s2 of the following segment is shifted by 1 interval between the pixels both in the direction of the X-axis and in the direction of the Y-axis with respect to the segment drawing ending pixel of the preceding segment, the arrangement of pixels as illustrated in FIG. 3B can be realized. That is, according to this invention, illuminated pixels are never arranged in such a manner that they give a visually unnatural expression, as indicated in FIG. 3A. When the drawing of the segments P sn in FIG. 13 by repeating the drawing of vertical segments as mentioned above (Step 113 in FIG. 11) is terminated, the procedure returns through Step 114 to Step 110. At this moment, since sx>Xq, the segment drawing subroutine for the vertical segments is terminated.
FIG. 12 shows the segment drawing subroutine for horizontal segments in FIG. 10 in detail. Steps 120, 121, . . . , 124 in FIG. 12 correspond to Steps 110, 111, . . . , 114, respectively. This subroutine differs from that for vertical segments only in that F(ex+1, sy+1/2)≧0 is used for the judgment in Step 121 and that the Y-coordinate of the segment drawing ending pixel is Y r . For the other parts only the X-axis and the Y-axis are interchanged by each other and the explanation of the treatment in FIG. 12 can be easily inferred from the explanation for FIG. 11. Consequently it is omitted.
In this way, the image to be drawn is drawn only with vertical and horizontal segments. Since the direction of each of the segments is automatically determined by using the inclination of the tangential line at each point of the image to be drawn and no complicated calculations are necessary for the determination of pixels to be illuminated, the drawing can be effected at a high speed. In addition, since the pixel data indicating the pixels to be illuminated is written all together in the image screen buffer, after the length of the segment (i.e. the number of pixels constituting the segment) has been determined, when the image screen buffer is constructed so as to be matched therewith, it is possible to write data at a still higher speed. For example, if the buffer 612 (in FIG. 6) is so constructed that 8 pixels are written by one operation for pixels aligned on one horizontal line, when pixel data representing a segment constituted by the pixels P 1 -P 5 as indicated by (a) in FIGS. 14A and 14B are written in the image screen buffer, writing is terminated by one access to the image screen buffer 612 with 1 byte data such as "01111100" indicated by FIG. 14B. Since, according to the prior art method, writing of pixel data was effected always for data of every pixel, speed-up can be obtained in this respect by the method according to this invention.
According to this invention, the determination of segments is effected by using an auxiliary line, which is shifted by 1/2 of the interval between the pixels in the direction of the X-axis or the Y-axis with respect to the coordinates of the actual pixel. However, according to a simplified method of this invention, it is also possible to conceive another method for determining the length of the segment by judging if the coordinates of pixels themselves constituting the segment traverse the image to be drawn or not. An example, in which 1/4 of a circle is drawn according to such a simplified method, is illustrated in FIG. 15A. It can be understood that FIG. 15B represents the features of the circle visually better, when FIG. 15A is compared with FIG. 15B, in which the same 1/4 of a circle is drawn by using an auxiliary line according to this invention.
Although, in the embodiments described above, only cases, where the produced segments are parallel to the X-axis or the Y-axis, are shown, this invention is not limited thereto, but it is also possible to form a more smooth curve consisting of a plurality of different types of segments previously determined. For example, it is useful in practice to adopt 4 directions (x, y, u, v) obtained by adding 2 directions forming 45° with the X-axis and the Y-axis thereto, as indicated by u and v in FIG. 16. In this case, the boundaries for classifying dy/dx are set for every π/8 rad, as indicated in the figure.
Although, in the embodiments described above, a CTR display device is used as an image output device, it is clear that a dot matrix type plasma display or a display using light emitting diodes, EL or LCD can be also used as well. Further, as the image output device, those which print outputs on a printed medium, such as an X-Y plotter, can be also used for realizing this invention. | The tangent α of the tangential line of an image to be drawn at each point in an orthogonal X-Y coordinate system is classified into two angle regions, a first angle region, where a condition -1≦α<1 is fulfilled, and a second angle region, where a condition α<-1 or 1≦α is fulfilled. The first and the second angle region is represented by the direction parallel to the X-axis and the direction parallel to the Y-axis, respectively. When the image to be drawn is displayed on a display screen, in the image to be drawn, the parts belonging to the first angle region are drawn with a plurality of segments, each of which is parallel to the X-axis, and the parts blonging to the second angle region are drawn with a plurality of segments, each of which is parallel to the Y-axis. That is, the image to be drawn is displayed on the display screen by using only segments parallel to the X-axis and those parallel to the Y-axis. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates generally to protection of remote sensing devices from interrogating radiation source and more specifically to optical devices which provide false reply signals to the interrogating source. Remote sensing devices such as missile seekers are often interrogated by radiation sources such as laser beams to determine the operating band of the sensor, its modulation rate, timing signal, chop frequency, or similar data which might be used to deteriorate the performance of the sensor. In addition the nature of these sensors is such that they have a high probability of being damaged from high amplitude incoming radiation. Thus a need arose for a device that would shield the remote sensing devices from interrogating radiation which could either damage its sensor or detect parameters of its operation or both.
OBJECT OF THE INVENTION
It is therefore the object of the present invention to provide an inexpensive and reliable device for shielding the sensors of a remote sensing device from interrogating radiation.
Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings wherein:
SUMMARY OF THE INVENTION
The present invention achieves these results through the use of beam splitting devices and false detection apparatus. In general, a beam splitter is used to divide part of the incoming light away from the detector to protect the detector from high power incoming radiation. The light which is divided away is operated on by a series of optical elements including chop wheels, filters, and false detectors to give false indications to the interrogating source. The beam splitter can also be coated with an optical filter so that only light of the operating frequency of the detector is transmitted to the detector.
BRIFE DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a remote sensing device without optical protection.
FIG. 2 shows a detecting surface of one embodiment of the invention.
FIG. 3A shows a second embodiment of the invention.
FIGS. 3B and 3C show modifications of the second embodiment of the invention.
DETAILED DESCRIPTION
FIG. 1 shows a typical remote sensing device having an optical element 10 to focus the incoming radiation and a detector 12 with a filter mounted on its surface. Incoming beams such as beams 13 and 15 will be reflected back along their axis and return to their point of origin. Similarly incoming beans such as bemas 14 which are at an angle to the axis of the optical system as shown in FIG. 1 will reflect a certain portion of radiation back to its origin since the filter and detector are usually not prefectly flat. The system in effect acts like a low grade retro-reflector. A laser or similar source can thus be used to interrogate the receiver by studying the radiation which returns from the sensor. In this manner the collimated source can determine the chop frequency, spectral response, general method of scan and similar parameters which might be used to counter the sensor. In addition, the same source might be used to damage the optical elements, filter and detectors of the sensor. If is thus desirable to provide means for protecting the sensors from both interrogating and damaging radiation.
FIG. 2 shows a detecting device for use with the structure of FIG. 1 which provides protection against interrogating radiation through the use of a series of false detectors. It consists of a conventional true detector 18 which is overcoated or covered with an interference filter 16 which provides spectral selectively for the true detector 18. Small partially absorbing semiopaque materials 20 are placed on top of the interference filter to act as false detectors so that either a symmetric or random array of various size flase and real detectors are seen by the interrogating radiation. The false detectors 20 are of approximately the same absorptivity as the real detector but with absorptivity peaks occurring at different wavelengths. The interrogating device will thus interpret the return as a variety of detectors operating at different spectral regions. The detecting device of FIG. 2 however, used in conjunction with the apparatus of FIG. 1, provides no protection against damaging radiation.
The apparatus of FIG. 3A shows another embodiment of the invention which protects its detector 24 from both interrogating and damaging radiation by addition of a beam splitter to the sensor optical system. Mounted on the beam splitter 22 is a reflective filter such as an interference filter which could be either bandpass or band limiting. The bandpass filter provides the greatest protection but is the most expensive to install and fabricate. In any event, the reflective filter allows radiation of a certain frequency to pass to the detector 24 while the remainder of the incoming radiation is reflected to reflective surface 26. The reflective surface can be made to have a broad band of absorptivity or selected bands of absorptivity. Additionally reflective surface 26 can be divided into a series of subareas similar to the false detectors of FIG. 2 having arbitrary sizes and reflectivities. Since both the detector 24 and the reflective surface 26 are primarily reflective, the preponderence of the radiation will be reflected back outside the receiver. Thus the false detectors of reflective surface 26 will make the receiver appear to the interrogating system as if it were operating in a different spectral region. In those instances where the incoming power is expected to be exceptionally large a totally reflecting surface such as collecting and return mirror 28 as shown in FIG. 3B can be used to offer the maximum degree of protection. In addition, radiation shields or baffles 32 can be used to block any scattered light from the detector 24. This modification also permits radiation to leave the optical system with the least amount of scatter. Of course, any motion imparted to reflective surface 26 will be interpreted by the interrogating system as another type of scanning and will imply different scanning frequencies.
FIG. 3C depicts a further modification of the second embodiment of the invention which allows power handling capabilities greater than the device shown in FIG. 3A. In operation, collimating lens 33 focuses the light reflected by the beam splitter on a large reflecting surface 34 similar to reflecting surface 26 in FIG. 3A. The collimated radiation from collimating lens 33 is reflected back from reflecting surface 34 whereupon the radiation continues to reverse its path until it exits the optical system. In effect a magnified image is formed on reflecting surface 34 of the image that would normally appear on reflecting surface 26 of FIG. 3A. Since the image is expanded on reflecting surface 34 it can handle incoming radiation which under other circumstances could not be handled by the reflective surface 26 in FIG. 3A.
Thus the invention will not allow the exact operating frequency or band of operation of the true sensor to be determined, but instead will only allow the reduction of possibilities to a few selected bands or frequencies. In addition, the beam splitter 22 of the second embodiment is flat and has a relatively small surface, and is thereby easily coated with an interference filter at a reasonable cost while accurately maintaining the frequency of its bandpass. Also, the present invention is compatible with presently existing systems and could be installed in them with out considerable modification.
Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described. | The invention presents means for protecting a remote sensing device such as missile seeker unit from damaging radiation outside of the sensing band of the detector and interrogating radiation attempting to determine the operating band of the sensor, its modulation rate, timing signal, or similar data which might be used to deteriorate the performance of the sensor. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to Korean Patent Application No. 10-2010-0076399, filed on Aug. 9, 2010, and all the benefits accruing therefrom under 35 U.S.C. §119, the contents of which in its entirety are herein incorporated by reference.
BACKGROUND
[0002] 1. Field
[0003] This disclosure relates to a centrifugal compressor, and more particularly, to an impeller which adds velocity energy to a compressible medium while rotating at high speed.
[0004] 2. Description of the Related Art
[0005] A compressor is a device for compressing gas by applying mechanical energy and is necessary for an air-conditioning apparatus such as a refrigerator to compress a cooling medium. There are different kinds of compressors, including a reciprocating compressor, a screw compressor, a centrifugal compressor, and the like. Particularly, the centrifugal compressor rotating at high speed has been widely used since fluctuation of a discharge gas does not occur and reductions in size and weight are easily achieved.
[0006] In general, a centrifugal compressor used in a freezer includes a casing having a cooling medium inlet port on one side, an impeller which is provided inside the casing for compressing a cooling medium flowing therein, a diffuser for converting kinetic energy of the cooling medium compressed by the impeller into pressure energy, and a volute for transferring the cooling medium passing through the diffuser to a discharge duct. The cooling medium flowing through the cooling medium inlet port of the centrifugal compressor is compressed by the impeller and the diffuser, passes through the volute and the discharge duct, and then is transferred to a condenser.
[0007] The impeller which may be considered as the heart of the centrifugal compressor includes a number of blades and applies centrifugal force to the compressible medium (the cooling medium) by rotating at high speed. Thus, there is a problem in that noise occurs.
SUMMARY
[0008] This disclosure provides an impeller which has an optimal structure to minimize noise and a centrifugal compressor including the same.
[0009] In one aspect, there is provided an impeller of a centrifugal compressor including: a hub fixed to a rotation shaft; and a plurality of blades extending outward from a center portion of the hub on one surface of the hub, wherein a length of the blade is greater than a straight length between an inlet end of the blade and an outlet end thereof. Assuming that an outlet angle formed along a longitudinal direction of the blade at the outlet end of the blade is β and an inclination angle of the blade from the one surface of the hub at the outlet end of the blade is γ, Equation (1) is satisfied:
[0000] 1<sin(β−20°)+cos(γ−40°)<1.5 (1)
[0010] The outlet angle β may be in a range of 20° to 70°.
[0011] The inclination angle γ may be in a range of 40° to 90°.
[0012] In another aspect, there is provided a centrifugal compressor including: an impeller which is fixed to a rotation shaft to be rotated at high speed; and a diffuser which converts kinetic energy of a compressible medium that is increased by the impeller into pressure energy, wherein the impeller satisfies Equation (1).
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The above and other aspects, features and advantages of the disclosed exemplary embodiments will be more apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
[0014] FIG. 1 is a cross-sectional view illustrating a centrifugal compressor according to an embodiment;
[0015] FIG. 2 is a perspective view of an impeller according to an embodiment;
[0016] FIG. 3 is a front view of the impeller for illustrating an outlet angle of a blade;
[0017] FIG. 4 is a partial side view of the impeller for illustrating an inclination angle of the blade;
[0018] FIG. 5 is a graph showing a change in noise level depending on a value of sin(β−20)°+cos(γ−40°) in regard to the outlet angle β and the inclination angle γ of the blade;
[0019] FIG. 6 is a graph showing a change in noise level depending on the outlet angle of the blade; and
[0020] FIG. 7 is a graph showing a change in noise level depending on the inclination angle of the blade.
DETAILED DESCRIPTION
[0021] Exemplary embodiments now will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth therein. Rather, these exemplary embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of this disclosure to those skilled in the art. In the description, details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the presented embodiments.
[0022] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, the use of the terms a, an, etc. does not denote a limitation of quantity, but rather denotes the presence of at least one of the referenced item. It will be further understood that the terms “comprises” and/or “comprising”, or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof.
[0023] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
[0024] In the drawings, like reference numerals in the drawings denote like elements. The shape, size and regions, and the like, of the drawing may be exaggerated for clarity.
[0025] Hereinafter, a centrifugal compressor according to an embodiment of the present disclosure will be described in detail with reference to the accompanying drawings.
[0026] FIG. 1 is a cross-sectional view illustrating a centrifugal compressor according to an embodiment. FIG. 2 is a perspective view of an impeller according to an embodiment. FIG. 3 is a front view of the impeller for illustrating an outlet angle of a blade. FIG. 4 is a partial side view of the impeller for illustrating an inclination angle of the blade. And, FIG. 5 is a graph showing a change in noise level depending on a value of sin(β−20°)+cos(γ−40°) in regard to the outlet angle δ and the inclination angle γ of the blade.
[0027] Referring to FIG. 1 , the centrifugal compressor 100 according to an embodiment includes a casing 10 , a rotation shaft 20 which penetrates the center of the casing 10 to be connected to a motor, an impeller 30 which is fixed to the rotation shaft 20 to be rotated so as to cause a compressible medium such as a cooing medium to flow therein, and a diffuser 40 which is disposed at a predetermined interval from the impeller 30 to convert kinetic energy of the compressible medium into pressure energy.
[0028] On one side of the casing 10 , there is provided an inlet port 12 through which the compressible medium flows and which is disposed in a longitudinal direction of the rotation shaft 20 . An inlet guide vane (IGV) 50 for controlling an inflow of the cooling medium is provided in the inlet port 12 . A bearing member 60 for supporting the rotation shaft 20 is provided on the rear of the impeller 30 .
[0029] The cooling medium compressed by the impeller 30 and the diffuser 40 is directed to the discharge duct through the volute 70 .
[0030] In the centrifugal compressor 100 having the above-described configuration, the impeller 30 includes, as illustrated in FIG. 2 , a hub 32 which is directly fixed to the rotation shaft 20 , and blades 34 which protrude from one surface of the hub 32 for inducing a flow of the cooling medium. The hub 32 may have various shapes such as a disk shape or a columnar shape having a width increasing in an axial direction in which the cooling medium flows.
[0031] A plurality of the blades 34 extend outward from the center portion of the hub 32 in a radial direction at predetermined intervals. Each blade 34 may extend in a streamline shape, and accordingly, an actual length (curve length) of the blade 34 may be greater than a straight length between an inlet end 342 and an outlet end 344 of the blade 34 .
[0032] The shape of the blade 34 has a great effect on the flow of the cooling medium. Particularly, the outlet angle β and the inclination angle γ of the blade 34 are factors having a great effect on generation of noise due to the flow of the cooling medium.
[0033] As illustrated in FIG. 3 , the outlet angle β of the blade 34 refers to an angle between a longitudinal direction (tangential direction) of the blade 34 and a tangential direction of the hub 32 at a point where the outlet end 344 of the blade 34 meets an outermost portion of the hub 32 . As illustrated in FIG. 4 , the inclination angle γ refers to an angle between a height direction of the blade 34 and a tangential direction of the one surface of the hub 32 at the outlet end 344 of the blade 34 .
[0034] The impeller 30 of the centrifugal compressor 100 according to an embodiment satisfies Equation (1) in regard to the outlet angle β and the inclination angle γ of the blade 34 .
[0000] 1<sin(β−20°)+cos(γ−40°)<1.5 (1)
[0035] The applicant discovered that noise generation by the impeller 30 is minimized when the outlet angle β and the inclination angle γ of the blade 34 satisfy Equation (1).
[0036] As illustrated in FIG. 5 , in regard to the outlet angle β and the inclination angle γ of the blade 34 , the noise generation is reduced when the value of sin(β− 20 °)+cos(γ−40°) is in the range of 1 to 1.5.
[0037] FIG. 6 is a graph showing a change in noise level depending on the outlet angle of the blade. FIG. 7 is a graph showing a change in noise level depending on the inclination angle of the blade.
[0038] Referring to FIG. 6 , when the outlet angle β of the blade 34 approaches 90°, pressure at the outlet end 344 of the blade 34 is increased, and thus the level of noise (blade-passing frequency (BPF) noise) is very high. However, the noise level is sharply reduced when the outlet angle β is 70° and is maintained at a predetermined level. Meanwhile, when the outlet angle β is smaller than 20°, a difference in speed between the cooling medium flowing along the outer surface of the blade 34 and the cooling medium flowing along the inner surface thereof increases rapidly at the outlet end 344 of the blade 34 , and thus the noise level is increased again. Therefore, in the centrifugal compressor 100 according to the embodiment, the outlet angle β may have a value in the range of 20° to 70°.
[0039] Referring to FIG. 7 , the noise level is maintained at a predetermined level or a smaller level when the inclination angle γ of the blade 34 is in the range of 40° to 90°. However, when the inclination angle γ is smaller than 40°, a difference in speed between the cooling medium flowing along the outer surface of the blade 34 and the cooling medium flowing along the inner surface thereof is increased, so that the noise level increases rapidly. Therefore, in the centrifugal compressor 100 according to the embodiment, the inclination angle γ may have a value in the range of 40° to 90°.
[0040] In the foregoing description, a single-stage centrifugal compressor has been described. However, this disclosure is not limited thereto. The number of the stages of the centrifugal compressor may be changed differently.
[0041] The centrifugal compressor according to the present disclosure includes the impeller which has an optimal shape based on the outlet angle and the inclination angle, so that there are advantages of high reliability in designing and a reduction in noise of the centrifugal compressor.
[0042] While the exemplary embodiments have been shown and described, it will be understood by those skilled in the art that various changes in form and details may be made thereto without departing from the spirit and scope of this disclosure as defined by the appended claims.
[0043] In addition, many modifications can be made to adapt a particular situation or material to the teachings of this disclosure without departing from the essential scope thereof. Therefore, it is intended that this disclosure not be limited to the particular exemplary embodiments disclosed as the best mode contemplated for carrying out this disclosure, but that this disclosure will include all embodiments falling within the scope of the appended claims. | Provided is an impeller of a centrifugal compressor including: a hub fixed to a rotation shaft; and a plurality of blades extending outward from a center portion of the hub on one surface of the hub, wherein a length of the blade is greater than a straight length between an inlet end of the blade and an outlet end thereof. Assuming that an outlet angle formed along a longitudinal direction of the blade at the outlet end of the blade is β and an inclination angle of the blade from the one surface of the hub at the outlet end of the blade is γ, the following equation is satisfied: 1<sin(β−20°)+cos(γ−40°)<1.5. | 5 |
RELATED APPLICATIONS
[0001] This application is a divisional application of U.S. patent application Ser. No. 09/903,444, filed Jul. 9, 2001 which claims priority to 60/216,854, filed Jul. 7, 2000 and is continuation-in-part of U.S. patent application Ser. No. 09/578,631, filed May 25, 2000, each of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to a method and apparatus for dispensing recorded optical disks, e.g., DVDs, employing computers and software. More particularly, this invention relates to a method and apparatus for providing automated retail distribution of recorded optical disks. Still more particularly, this invention relates to a method and apparatus for providing a freestanding distribution and retrieval system for recorded optical disks, which is linked to a central server computer using the Internet.
[0000] Problem
[0003] One method commonly used for distribution of optical recorded media is a retail outlet. A retail outlet may sell or rent the optical recorded media. A large optical media inventory is common at a retail location, and staff is required for sales, rentals and restocking. A building is required to house this inventory and to provide a retail location. A computer system is usually employed to track inventory of rentals and sales. A retail outlet for recorded media is very expensive to construct and operate. Because of these factors, there is considerable overhead required to run a rental or sales business for recorded media.
[0004] Another method of media distribution is a limited scale operation. A convenience store might offer a limited selection of items for sale or rent. However, staff is still needed for sales, rentals and restocking. A significant limitation of the retail distribution model for optical recorded disks is the overhead required to operate a business.
[0005] One way that retailers and manufacturers have sought to reduce costs is through electronic commerce (EC). A system of distribution using EC can reduce overhead associated with retail locations and with sales operations. In this type of business model a central warehouse or warehouses ship an order submitted via the Internet through the mail or using a private courier. The cost of operating a retail location is avoided with this business model. However, Internet-based distribution systems often have significant liabilities. One such liability is that a customer must wait for an order to be shipped from a warehouse location. Another disadvantage is that stock may not be available at the time the order is processed. If stock is unavailable, an order may be placed on back-order or the order may be canceled. Another significant disadvantage of an Internet-based distribution system is the impracticality for media rental. The rental business is one of immediacy; a customer will rent an item that is available immediately, but may not rent if it is not available immediately. A customer is much less likely to rent an item that is shipped after ordering, requiring days for delivery. In addition, once a customer is finished with a rented item it must be return-shipped to the distribution location.
[0006] An advantage of an Internet-based distribution, however, is that a customer may set up an account, pay electronically, and provide invaluable information to a retailer, wholesaler or the media industry. What is needed is an Internet-based distribution system that allows a customer instant distribution or retrieval of optical recorded media (e.g., DVD disks) that does not require a retail outlet with the attendant staff and other costs of doing business. In addition, there is a need to provide automated services for payment and quality assurance such that a distribution system is simple and inexpensive to construct and maintain.
SUMMARY OF THE INVENTION
[0007] The above and other problems are solved, and an advance in the art is made, through the invention by methods and systems for Internet-based automated distribution and collection of optical recorded disks.
[0008] A first aspect of the invention is the ability to provide automated distribution of optical recorded disks, such as DVD-type optical disks. A stand-alone automated kiosk serves as a distribution point for an integrated system of automated distribution linked via the Internet. The kiosk is an Internet-connected, electro-opto-mechanical system providing storage, maintenance, marketing and dispensing and retrieval of optical recorded disks. A carousel or shuttle system provides access to multiple media selections within the kiosk. Multiple kiosks may be connected to the system via the Internet for simultaneous use by users at different locations. Multiple kiosks may further be managed from a central location, such as to provide remote maintenance and efficient operation of commonly-owned multiple kiosks through multiple locations.
[0009] In one aspect, a user interacts with the system via a touch screen. The system software guides each customer through the process, preferably using linked pages connected to a database. A selection is entered on the touch screen to choose one or more items for rental or sale. The selections are added to a “shopping cart,” or a temporary database represented on the display, that is approved by the customer. A credit or debit card or other membership information may be entered using a magnetic strip card reader or other device that imports the data to a verification module. Approval or denial of credit is accomplished via a local database, and/or via a connection to the system central server computer, and/or via a connection to banking services. If the credit or debit is approved, the on-going transaction is attached to a customer, approval for the price of the disk is entered, and a dispensing system is activated. A database then queries software for the requested item location. A carousel or shuttle system manipulates the media until it is aligned with the dispensing/retrieving slot. A door mechanism is activated to open, and a mechanism is activated to push the optical recorded disk partially out of the slot to make it available for hand retrieval by the customer. The disk is contained within a special case, preferably.
[0010] In another aspect, the invention provides for emailing transaction information to a customer. By way of example, during the disk dispensing operation, an option to receive an e-mailed receipt is given. The option contains a touch-screen keyboard pop-up for the purpose of entering email address characters and other data. A consumer enters an email address via the touch screen keyboard. Receipts may include transactional information as well as advertising and links to specific web sites. All receipts are given by e-mail reducing the expense of a kiosk since a hard-copy receipt printer is not required. Additionally, the system acquires e-mail addresses from customers allowing post transaction interaction while the consumer is on online. These receipts may also contain advertisements and promotional information as well as web links. These advertisements and promotions may be targeted to customers based on their profile data.
[0011] Optionally, users of a system of the invention may access the Internet to review one or more kiosks in the area, or elsewhere, so as to pre-locate a desired optical media for purchase or rent. Such users may enter email addresses and purchase information at a computer connected with the Internet, and hence with the system, to facilitate these operations; these users may then physically access an appropriate kiosk to obtain their chosen optical recorded media.
[0012] Yet another aspect of the present invention is the ability to receive returned optical recorded media to the system. The customer activates a return process by selecting “return rental” button from the touch screen menu or by presenting the disk to the system bar-code reader or optical sensor. The carousel or shuttle system positions to accept the disk at the opening. An initial sensor detects if the recorded disk belongs to the system and activates a door mechanism to allow placement of the recorded disk in the opening. If the recorded disk does not register as a system disk, the door mechanism will not allow the disk to enter the opening. Once registered, the individual code associated with each item is entered into the database and the position in the carousel or shuttle is stored. An open transaction is closed when the item is returned and logged in the database, or sold. The location of each item is stored in the database upon insertion through the return slot. Recorded disks are stored in case containers specific to the system; these cases may include certain lock and key structures that enable early identification of the case. Preferably, item-specific identifiers—e.g., barcodes—are present on the optical recorded media to further identity of the individual disk.
[0013] Still another aspect of the present invention is automatic restocking of the kiosk system. Customers return the optical recorded media to the system. A single-touch selection or sensor-activated initiation of the system starts the process. The kiosk system rotates the carousel into the appropriate alignment of the opening to the selected inventory slot. Once in the appropriate alignment, and upon recognition of the system-specific barcode, the door opens for acceptance of a cased recorded disk. As the case passes through, the door mechanism pivots to decline additional insertions until the system is ready. The location information is then stored in the computer, restocking information is downloaded to the central server, and the disk becomes available for subsequent rental or sale.
[0014] Optionally, users of the system in certain markets (i.e. airports) may elect for the ability to return the optical media to administration by means of a mail-back program. For example, business reply envelopes can be made available to users at the kiosk and, for an additional cost, can simplify the return process for the user (i.e. a one way commuter).
[0015] In one aspect, the invention provides a “thin client” optical media rental system. Each kiosk of the system is a thin client connected to a core server through the Internet. As used herein, “thin client” means that each kiosk provides basic electro-opto-mechanical functionality sufficient to perform the operations required at the kiosk; but the overall system intelligence resides at the core server. This aspect provides certain advantages to facilitate maintaining a plurality of connected kiosks dispensing an array of optical media (e.g., DVDs) at different locations.
[0016] In another aspect, the invention provides a special optical media housing, typically in the form of a DVD case, with a “lock and key” structure to facilitate automated rental returns. In a related aspect, each such housing has a sensor, e.g., a magnetic actuator, attached thereto; the kiosk senses the actuator to determine that the case belongs to the kiosk (or to one of a connected array of kiosks grouped or linked to the central server). Preferably, the case sensor is an optical sensor formed by a hole and a blocked zone; the kiosk picks up the right sequence to accept that housing to the kiosk. This process is sometimes called “pre-scanning” herein. In pre-scanning, the kiosk will not open its door to accept a housing with optical media unless the kiosk first detects the case sensor. Preferably, the kiosk door also remains closed unless the bar codes are read from the optical recorded media, as described below.
[0017] In another aspect, once the kiosk determines that the housing is acceptable, the kiosk scans at least one bar code on the optical media. Preferably, two bar codes are read, specifying a “group” association and an individual media identification. A “group” bar code specifies how one optical media may travel between kiosks (for example, one distributor may control several kiosks and yet permit returns to any of the kiosks). An “individual media identification” bar code may generally be a serialization of one DVD in an array of DVD disks.
[0018] In another aspect, the invention provides a bar code scanning process for accepting returned optical recorded media to one or more kiosks connected to a core server. An optical reader scans the optical media through a clear case housing. The case preferably has an indented zone in its center so as to clearly read the bar code(s) through the case. The process preferably performs multiple “reads” of the bar code(s) to ensure that the kiosk (and hence the system) correctly identifies the optical recorded media. In one aspect, the kiosk takes a digital picture of the media during the return process; it then attempts to read the bar code(s) from the digital picture. If unsuccessful, kiosk software “rotates” the image so as to read the bar code(s) from a different angle. This process may continue; but it is generally successful within one or two subsequent rotations.
[0019] In yet another aspect, a system of the invention includes a central database connected to a plurality of kiosks. All transactions such as “rent” and “returned data” at each kiosk are downloaded to the central database server. Preferably, each kiosk maintains a backup memory of certain information from the central database server, so that transactions may occur even in the event of communication failure between the kiosk and database server. By way of example, each kiosk may contain 12G-bytes of memory to store the certain information from the database server.
[0020] In still another aspect, the invention provides an automated customer profiling system. The system tracks interactions from customers at either a connected kiosk or at a computer connected to the database server through the Internet. Customers may be profiled according to individual information, such as movie-type preferences. Such a system may further send and accept “e-coupons” so as to discount certain rental offerings at one or more local kiosks. By way of example, the system may send an email to a customer to offer a discount rental for a DVD optical media at a near-by kiosk; that customer may accept the discount by interaction with the central database server through the Internet, or he may print the coupon and enter the coupon code at the near-by kiosk. E-coupons may thus incorporate promotion codes as individual numbers that are entered at the kiosk for discounts; accordingly, in one aspect, a kiosk of the invention includes a keyboard graphically represented at the kiosk touch screen. In one preferred aspect of the invention, discount magnetic stripe cards (i.e. grocery store club cards) are used for promotional discounts. In another preferred aspect of the invention, e-coupons used at a kiosk within the system of the invention may be tracked to assess advertising effectiveness.
[0021] Users of kiosks of the invention are preferably characterized by unique credit card numbers. Information that is attached to a user profile generated at a kiosk includes e-mail address and transactional data. Additional information can be initiated through the Internet or added to a pre-existing account, including phone number, address, and/or membership data
[0022] In another aspect, a system of the invention provides real time inventory of connected kiosks. A user of the system can access the Internet and review the DVDs available at any of the connected kiosks. Inventory statistics are also prepared, preferably; such statistics are useful for example to flag those movies often rented and those that are not, so that multiple versions of highly rented movie may be made available to users.
[0023] In one aspect, a kiosk of the invention includes a vertical carousel housing 102 DVDs; the volume footprint of the carousel housing is approximately 24″×25″×15″. A kiosk with such a carousel may be mounted in four different ways: on a pedestal, on a wall, on a counter-top, or in a wall. In the latter case, a “quick mount” frame is used to house the kiosk for mounting within a wall, in another aspect. A kiosk of the invention preferably is “plug and play”, requiring only a phone line and a power cord, to begin operations. By way of example, a user of the kiosk purchases or rents the kiosk for use at his store; he mounts the kiosk on a store wall, plugs the kiosk to 110V power, and connects the kiosk to a phone line, which in turn connects internal kiosk intelligence to the central database server.
[0024] In another aspect, the mechanical design of a kiosk of the invention preferably utilizes a camshaft to time the door, the door lock, and the pinch rollers.
[0025] In another aspect, the kiosk is cooled by sinking heat to the housing to dissipate internally generated heat, thus eliminating external fans and other means of housing penetration.
[0026] In still another aspect, mechanical elements of the kiosk are preferably extruded and welded to other components in an efficient process flow.
[0027] In one aspect, a kiosk of the invention utilizes a card reader and associated software to read and conduct transactions with magnetic stripe cards such as credit cards, debit cards, club cards, or smart cards. In a preferred aspect, the card reader performs age verifications, to ensure rentals are made to appropriate age groups; as such, one card reader of the invention also provides for reading driver licenses or other identification.
[0028] One preferred kiosk of the invention includes an advertising module. Advertising information, such as trailers and advertisements, are downloaded from the central database server and stored on a local drive. Advertising information may be “customized” to any kiosk location according to typical user preferences and, for example, specific demographics. The advertising information may further include video advertisements played at the kiosk for display to users thereby. Play-lists may thus be customized for each location, and locally selected, but administered centrally through connection between the kiosk and the central server. Simplified administration screens connecting administrators to the central server facilitate control and selections at a connected kiosk.
[0029] Advertisements used in kiosks of the invention may be digital still images or motion video in MPEG2 format, or other suitable formats. Advertising files are inventoried on the core server and then downloaded on request to the requested kiosks. This file is then stored locally at the kiosk (e.g., within kiosk memory) and may be inserted into the advertising play list in as many slots as needed. The list plays continually in a looped format during requested hours. Play lists may be shown on an LCD display on the face of the kiosk and/or on additional external monitors.
[0030] The invention is next described further in connection with preferred embodiments, and it will become apparent that various additions, subtractions, and modifications can be made by those skilled in the art without departing from the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] A more complete understanding of the invention may be obtained by reference to the drawings, in which:
[0032] FIG. 1 illustrates the recorded media distribution system of the invention;
[0033] FIG. 2 is a block diagram of a system kiosk, in accord with the invention;
[0034] FIG. 3 illustrates a system central server, in accord with the invention;
[0035] FIG. 4 is a block diagram data exchange within the distribution system, according to the invention;
[0036] FIG. 5 is a flowchart of a system transaction, in accord with the invention;
[0037] FIG. 6 is a block diagram of an exemplary computer system of the invention, suitable for use with a kiosk or system central server database;
[0038] FIG. 7 is a depiction of a bar code and optical disk used in accord with the invention;
[0039] FIG. 8 is an exemplary perspective view of a preferred embodiment of a kiosk, in accord with the invention;
[0040] FIG. 9 shows a perspective view of internal mechanics, including a carousel, for a kiosk of the invention;
[0041] FIG. 10 shows a perspective view of spindle mechanics for the carousel of FIG. 9 , and further illustrates placement of speakers for a kiosk of the invention;
[0042] FIG. 11 shows a perspective view of a carousel of the invention;
[0043] FIG. 12 shows an encoder and motor for use in a kiosk of the invention;
[0044] FIG. 13 shows other internal drive shaft and electro-mechanical components within a kiosk of the invention;
[0045] FIG. 14 illustrates opto- and electro-mechanical components of a kiosk using digital cameras and input/output mechanics for optical recorded media, in accord with the invention;
[0046] FIG. 15 shows further detail of the mechanics of FIG. 14 ;
[0047] FIG. 16 shows further detail of the mechanics of FIG. 15 ;
[0048] FIG. 17 shows camshaft operation detail within a kiosk of the invention;
[0049] FIG. 18 shows a front view of a carousel of the invention;
[0050] FIGS. 19-22 illustrate additional detail of parts extruded in making the carousel of FIG. 18 ;
[0051] FIGS. 23-24 show a case for enclosing an optical recorded media, in accord with the invention; and
[0052] FIG. 25 illustrates operation for inserting a disk case into a kiosk, in accord with the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0053] In the following detailed description of the present invention, a method and system are provided for Internet-based and automated recorded media distribution and retrieval; specific details are set forth in order to provide a thorough understanding of the present invention. It will be obvious, however, to a person skilled in the art that the present invention may be practiced without these specific details, and changes may be made to the description herein without departing from the scope of the invention.
[0054] The integrated recorded media distribution system is centered on combining instant physical access to recorded media with the convenience of Internet based e-commerce. The system is particularly adapted to support Digital Versatile Disk (DVD) recorded media, and other optically recorded disks.
[0055] In the preferred embodiment, an Internet-connected central server integrates customers, suppliers, employees, kiosks, owners, and the video industry in a “Hub and Spoke” system that is preferably automated and interactive, providing real time business-to-consumer and business-to-business capabilities.
[0056] The system kiosks are part of the Hub and Spoke network system. The kiosks act as brick and mortar spokes, providing a faster, more convenient way for customers to obtain and return DVD videos or other optical recorded media. Each kiosk is a self-service unit that combines electro-mechanical dispensing devices and components, Internet connectivity and a touch screen monitor for customer interaction. The compact nature of the DVD format allows up to 102 disks to be stocked in a kiosk, like the kiosk shown in FIG. 8 . The kiosk's small space requirement allows placement in high-traffic locations that are more convenient than traditional retail locations. Internet connectivity allows customers to have the choice of shopping online or on-site or to access a variety of real-time services.
[0057] Each kiosk is a self-service unit that includes an internal processor, Internet connectivity, and a touch screen monitor for customer interaction. The small physical footprint of the kiosk enables it to be placed in a variety of locations. The kiosks can operate 24 hours a day, 7 days a week, providing instant electronic access to products. The kiosks are fully automated providing customer service through the Internet; on-site staffing is not required to support customer needs. The system web site provides 24-hour access to on-line customer support. It also provides access to specific kiosk inventory, movie trailers and reviews, customer inquiries, special orders, regular individually tailored e-mailed updates, and overall service. The integrated remote kiosk monitoring system allows low cost inventory management, tailored marketing promotions, operations planning, advertising management, and system diagnosis.
[0058] In the preferred embodiment, the kiosks are physically designed to meet American Disabilities Act (ADA) specifications so that they may be placed in public facilities. The kiosks also preferably meet other regulatory requirements of public transportation facilities, universities, and office buildings.
[0059] The system central server supports a World Wide Web site. The central server includes promotional drivers and accessory services that route through the system website in conjunction with the kiosks. Customers may use the Internet to query a specific kiosk for availability, or to purchase new and used optical recorded media, register for e-mailed updates, or participate in various targeted programs.
[0060] The integrated system allows fast transactions. A simple and easy to use title search process minimizes shopping time and allows rapid transactions. Transaction times from walk-up to walk-away can be less than 40 seconds and average 2.5 minutes. Return of media is also simple, as the disks only need to be re-inserted into the dispensing/retrieval mechanism. Upon the return of a disk at a kiosk, the internal computer reads individual identification information from the disk and restocks it automatically.
[0061] The system allows remote price changes and can also gather up-to-the minute product availability and customer data. Thin-client computing technology keeps hardware costs low and speeds up application deployment by centralizing management, and enhancing security. E-mailed receipts generated from the kiosks through the central server allow ongoing access to customers after the completion of the transaction.
[0062] Recorded disk pricing may be determined on a kiosk-by-kiosk basis based on local market conditions. Pricing also varies depending on market elasticity; for example, premiums may be placed on DVD videos available in airport terminals. Differentiated pricing can be used for newer releases vs. older releases. In addition, rental terms and promotions may vary based on kiosk locations and the time of week, and can be adjusted remotely on demand.
[0063] At a kiosk such as shown in FIG. 8 , a graphical user interface (GUI) utilizing a touch screen display provides a user-friendly interface even to consumers lacking computer experience. Once a touch screen is activated, a computer in the kiosk generates a touch-selectable list of available media: movie genres such as Action, Drama, Romance, and Comedy, for example. By touching on one of the genres, a selection of associated titles and/or a promotional picture may appear on the screen. Touching an image causes basic information to be displayed about that media such as cost and rating, along with an option to rent or purchase the media. When selection of media is complete, a credit, debit card, and/or other membership ID is requested to execute the transaction and then the disk is dispensed to a customer.
[0064] Return of rental media is similar; a customer may select “Rental Return” button on a touch screen, and then insert a disk into an opening in the kiosk. An optical scanner first verifies that the disk belongs to the system before accepting a disk.
[0065] Internet connectivity and a dynamic customer database provide product promotion capabilities and consumer access. Product information and promotions may be tailored to each location's demographics and additionally to each kiosk's rental and sell-through history. Advertising is available on the kiosk, kiosk screen, additional associated monitors, disk cases, dispensed coupons, e-coupons, e-mailed receipts, and through various web-based interactions. Advertising with the kiosk system provides mechanisms to promote specific marketing initiatives as well as additional local and global advertising. The system website allows consumers to search for kiosks and to query a specific kiosk for available content. The website also carries updated lists of used media for sale at discounted prices at individual kiosks. A customer may reserve and pay for a DVD stocked at a specific kiosk from the website, then pick up the DVD within a specified time period at the specific kiosk. Once a customer enters e-mail information at the kiosk or at the website, that customer is eligible to receive frequent tailored e-mailed updates and e-coupons from the central server on current promotions.
[0066] Additional products potentially distributed through the kiosks include a variety of recorded media such as books on optical recorded disks, DVD music videos, DVD-ROM, DVD video games, DVD-Audio, SA-CDs and CDs. The modularity of the system allows for easy adoption of additional disk-based content distribution.
[0067] Some portions of the following detailed description are presented in terms of procedures, logic blocks, processing steps, computer program code and other symbolic representations of data operations within a computer memory. A procedure, logic block, process, etc., is a self-consistent sequence of steps or instructions leading to a desired result. The steps are those requiring physical manipulations of physical quantities.
[0068] A practitioner will recognize that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated, terms such as “processing,” “computing,” “calculating,” “determining,” “displaying,” refer to the action and processes of a computer system or similar electronic computing device.
[0069] FIG. 6 illustrates a computer system 612 suitable for use in the kiosk of FIG. 8 , or in central server 103 , FIG. 1 . In general, computer system 612 used by the preferred embodiment of the present invention comprises a bus system 600 for communicating information between system components. A central processing unit 601 for processing information and instructions is coupled to bus system 600 . A processing unit may be a processor, a microprocessor or any group or combination of processors or microprocessors. A random-access memory 602 for storing information and instructions for the central processor 601 is coupled to bus system 600 . A read-only memory 603 for storing static information and instructions for the processor 601 is coupled to bus system 600 . A data storage device 604 , such as a magnetic or other disk drive, for storing information and instructions is coupled to bus system 600 . A display device 605 for displaying information to the kiosk user is coupled to bus system 600 . An alphanumeric input device 606 , including alphanumeric and function keys (e.g., a touch screen), for communicating information and command selections to the central processor 601 , may be coupled to bus system 600 . A cursor control device 607 for communicating user input information and command selections to the central processor 601 may be coupled to bus system 600 . A signal-generating device 608 for communicating data or signals between devices external to system 612 and processor 601 may be coupled to bus system 600 .
[0070] FIG. 1 illustrates a preferred embodiment of an optical disk distribution system 100 . Generally, system 100 distributes recorded optical media in disk form; for example a Digital Versatile Disk (DVD), or a Compact Disc (CD). A disk, recorded disk, DVD, CD, or recorded optical media are used interchangeably herein to refer to an optical recorded media. System 100 integrates one or more kiosks 101 with a server system 103 through a virtual network 107 that uses the Internet 104 . Server system 103 is connected to the Internet 104 also for direct linking to individual email accounts 105 and 105 ′. Server 103 supports a World Wide Web page set 108 for general access by customers using the Internet 104 . Generally, access to system web page set 108 supported by server 103 is through an Internet Service Provider (ISP) that provides an Internet connection for a personal computer 106 . Kiosk 101 has a display 106 for viewing and entering information. Kiosk 101 dispenses and receives disks 102 , via an opening in its front.
[0071] FIG. 2 illustrates a schematic embodiment of a kiosk 200 (e.g., kiosk 101 , FIG. 1 ). Kiosk 200 is a self-contained unit dispensing system that contains computer devices and mechanical devices. A central processing unit 201 is operably connected to a system bus 250 . System bus 250 may be a single bus or a series of busses for communicating data or signals between various devices and central processing unit 201 . A memory device 202 for storing instructions and/or other information is operably connected to system bus 250 . A data storage device 203 for storing data, or containing databases and/or other instructions, is connected to system bus 250 . A display device 204 having alphanumeric input capability is operably connected to system bus 250 . A magnetic card reader 211 for reading magnetically imprinted cards is operably connected to system bus 250 . Any device suitable for uniquely identifying a customer such as a smart-card, license reader, fingerprint scanner/identifier, or other identification device may be substituted for, or augmented to, magnetic card reader 211 when appropriate. An optical reader 205 for reading bar codes is operably connected to system bus 250 . Reader 205 may include a digital camera to view optical media and an associated housing, to facilitate access control of media to the kiosk. A disk shuttle assembly 206 for accessing and storing disk media is operably connected to system bus 250 . A media storage unit 207 for storing optical media 214 is contained in kiosk 200 . Shuttle assembly 206 may be contained in, or integrated with, media storage unit 207 for accessing optical media 214 . A kicker device 208 for dispensing or receiving optical disk media 214 is operably connected to system bus 250 . A communications device 216 such as a modem or network connection is operably connected to system bus 250 . An optional audio device 212 for providing kiosk sound capability may be connected to system bus 250 . An optional DVD-Ram or DVD-ROM drive 213 for reading data from, or writing data to, optical media may be operably connected to system bus 250 . An optional coupon-dispensing device 217 may be operably connected to system bus 250 . An optional alarm state recognition device or algorithm 218 may be connected to system bus 250 . An optional secondary transaction device 219 for processing custom banking processes such as local debit card transactions may be connected to system bus 250 .
[0072] An optional error detection system 209 for detecting damaged optical disc media may be internal to or external to kiosk 200 . When error detection system 209 is internal to system kiosk 200 , error detection system 209 is operably connected to system bus 250 , and DVD-RAM or DVD-ROM drive 213 is operably connected to system bus 250 . Other output/input signal devices 210 may be connected to kiosk 200 , as needed. By way of example, one input device 210 includes a digital camera for capturing images of persons and/or objects near to kiosk. Such a camera is useful, for example, in capturing the user while he or she inputs identification or credit card information; later the information may be compared to the input data in the case of fraud. By connecting camera device 210 to bus 250 , images captured thereby may be downloaded to the central server, as needed, in this process.
[0073] An optional advertising device 215 for broadcasting advertising and promotional materials to additional monitors may be internal or external to kiosk 200 ; when advertising device is internal to kiosk 200 , advertising device may be operably connected to system bus 250 , as shown.
[0074] Those skilled in the art should appreciate that kiosk 200 may alternatively function with computer system 612 as at least part of internal schematic items 201 , 202 , 203 , 204 .
[0075] Each kiosk 200 preferably has a database stored in memory 203 of its kiosk inventory; and this inventory is preferably duplicated at the core server 103 , FIG. 1 . Memory 203 also preferably stores a set of kiosk parameters specific to a kiosk. This set is fed from the core server 103 and includes any local language translations, logos, color schemes, advertisements or video graphics, and the advertising play list. All transactional data passes through to core server 103 and is preferably not stored, long term, in local memory 203 .
[0076] Kiosk 200 interacts with a central server preferably as shown in FIG. 1 . Central server 103 preferably polls each individual kiosk 103 (e.g., kiosk 200 ) for status information, every five or ten minutes, for example. If the information from kiosk 200 is not normal, then one or more alarm states are generated to administrators of the central server. Alarm states may be generated for any of a variety of reasons, for example indicating: that kiosk 200 is not on; an incorrect inventory; security breaches; incorrect readings by any internal device or sensors; and combinations thereof. This feature is very powerful to assist in management of the array of kiosks. Alarm state messages may be relayed to a core server administrator by email, pager messages, cell phones and the like, and in near real time to indicate a problem at any of the connected kiosks 101 .
[0077] FIG. 3 is an illustration of a preferred embodiment of a central server computer 300 . The system central server computer 300 may also be computer system 612 . System server 300 provides command and control and collects and delivers data to and from kiosk 200 . Server computer 300 has a central processing unit 301 that is operably connected to server system bus 350 . A memory device capable of storing instructions 302 is operably connected to server system bus 350 . A database 303 for storing data is operably connected to system bus 350 . A communication device 351 capable of transmitting and receiving data or html 304 is operably connected to system server bus 350 . An optional second communication device 353 for exchanging data for commercial transactions 305 may be operably connected to server system bus 350 . An optional secondary transaction server device 306 for processing secondary transactional data such as grocery store club card data may be operably connected to server system bus 350 ; server device 306 may alternatively be a connection to facilitate connection to a remote server to accomplish like function.
[0078] FIG. 4 depicts a preferred embodiment of the system data transfer mechanism 400 . Mechanism 400 for example facilitates item 107 of FIG. 1 . A virtual network connection 107 provides data exchange between kiosk 200 , FIG. 2 , and server computer 300 , FIG. 3 . The kiosk-server virtual network system 107 can be a local network system or a remote network system that may utilize an html-based data exchange, e.g. an intranet or extranet. The exchange of data in html format includes an html request 425 and an html page 435 ; alternative communications between server computer 300 and ISP 401 may occur through signal line 420 . Both kiosk 200 and server computer 300 may request and receive data using the html protocol, allowing a two-way data-exchange system. The use of the html protocol allows an Internet browser to be a system interface, and additionally allows system 100 , FIG. 1 , to be administered by an Application Service Provider (ASP) using the Internet. An ASP provides software applications across the Internet by basing resident software on central server 103 that is accessed using an Internet browser. The use of ASP's is desirable where the functionality of a network is desired, but the use of a private server-system is impossible or impractical. An Internet Service Provider (ISP) 401 may also be an ASP. ISP 401 provides a connection to the Internet to individual computer users.
[0079] Exchange of data using virtual network 107 , FIG. 1 , is accomplished in a secure manner using methods of data encryption and decryption known in the art. Secure transfer of data through ISP 401 provides a virtual private network connection. An additional data exchange may occur on a dedicated private network connection for banking services, or alternatively using a virtual network as in item 107 . Server computer 300 may obtain credit or debit or other membership authorization using information received from a customer. A credit authorization request 412 is transmitted from server 300 to a bankcard verification service 410 , which generally is a secure server computer. After receiving credit authorization request 412 , bankcard verification service 410 processes credit authorization request 412 , and transmits a response 411 to server computer 300 . Response 411 is conveyed to kiosk 200 , FIG. 2 , through virtual network 107 , FIG. 1 .
[0080] FIG. 5 illustrates a preferred embodiment of a disk-dispensing transaction process 500 , in accord with the invention. Process 500 begins with a request to dispense a media selection from kiosk 200 , FIG. 2 , in step 501 . Information including, for example, credit-card number, and/or license or identification information, is next received from a customer to kiosk 200 , in step 502 . Kiosk 200 then securely transmits data received in step 502 to ISP 401 , FIG. 4 , in step 503 . Data securely transmitted in step 503 is received to ISP 401 in step 504 . Data received to ISP 401 in step 504 is securely transmitted to system server 300 , FIG. 3 , in step 505 . Data securely transmitted to system server 300 in step 505 is next received at system server 300 in step 506 . System server 300 next securely transmits debit and/or credit authorization request data to a credit verification server in step 507 . System server 300 next securely receives credit authorization data from a credit verification service in step 508 . System server 300 next securely transmits authorization data received in step 508 to ISP 401 in step 509 . In step 510 , data transmitted by system server 300 in step 509 is received by ISP 401 . In step 511 , ISP 401 securely transmits to kiosk 200 authorization to dispense requested media received from system server 300 in step 510 . In step 512 , kiosk 200 securely receives authorization to dispense media transmitted from ISP 401 . Optionally, in step 513 , an email address is securely received for customer. In step 514 , kiosk 200 dispenses requested media to a customer. In step 515 , system server 300 transmits to ISP 401 an e-mail receipt for a debit transaction occurring in steps 507 and 508 for an e-mail address supplied in step 513 . In step 516 , ISP 401 transmits email receipt data received from system server 300 in step 515 to an email address received in step 513 .
[0081] In a preferred embodiment of the invention, shown in FIG. 7 , an optical bar code 701 uniquely identifies each recorded disk 700 , A region on the case between the media outside diameter 705 , and the center region 704 may be used for a label region 702 . A center region 704 exists between the label region 702 and the center hole 703 . The center region 704 may contain printed information (e.g., a bar code) on both single-sided and double-sided optical media. For recorded disk 700 , barcode 701 is read by capturing a digital picture of barcode 701 , and then internal software to kiosk 200 rotates an image of barcode 701 to perform one or more “pseudo” scans of barcode 701 .
[0082] FIG. 8 is an exemplary perspective-view embodiment of a kiosk 200 , FIG. 2 . A kiosk housing 900 forms an enclosure. The outer dimensions of housing 900 may be about 25″ tall, 25″ wide, and 15″ deep. A computer, e.g., computer 612 , FIG. 6 , or CPU 201 , FIG. 2 , is included inside housing 900 . A touch screen display 904 is positioned on the front of housing 900 . Display 904 may show advertising play list images and movie trailers in addition to providing user interface functions described herein. An input/output slot 940 is positioned on the front of housing 900 to dispense and receive optical recorded media disks. A magnetic strip reader 911 is positioned on the front of housing 900 . A transfer mechanism/controller is included in housing 900 to manipulate disks into and out of housing 900 . This transfer mechanism may be shuttle/carousel 206 , FIG. 2 , or the structures illustrated in FIGS. 9-18
[0083] In the preferred embodiment, touch screen display 904 has an LCD backed up by a metal plate to protect internal components should the LCD break. Around display 904 is a cast bezel 920 , providing protection for the customer and the display 904 . The display LCD may be sealed to bezel 920 to protect it from fluids and moisture. Bezel 920 is angled at the top 921 to discourage people from placing objects on it.
[0084] Access to inside of housing 900 is through a cam lock 924 . Access within housing 900 facilitates mounting or dismounting of housing 900 to walls or other surfaces; internal access is also used to access power and communications connections. The key for cam lock 924 cannot be removed in the unlocked position.
[0085] Magnetic strip reader 911 is used by kiosk 200 , FIG. 2 , to identify a customer or member, and/or to bill the customer, and/or to verify age. Reader 911 is thus preferably usable with magnetic strips used in driver's licenses, credit cards, membership cards, student body cards, etc.
[0086] All cases and optical media inventory normally enter and exit thru Input/output slot 940 . Housing 900 and slot 940 thus cooperate to protect media inventory; specifically, inventory cannot be removed from housing 900 (e.g., by stealing) without breaking the housing and optical media. Authorized access can only occur through use of cam lock 924 and special tools used to disassemble the carousel from the spindle (described in more detail below). Slot 940 is also constructed to prevent a person from inserting a finger into internal working mechanisms.
[0087] Cast covers 926 and 927 protect input/output mechanisms of slot 940 , and further shields the bar code scanner/camera (described in more detail below) housed internally to housing 900 . Cast covers 926 and 927 may only be removed from the inside with tools.
[0088] Housing 900 includes a sheet metal enclosure 901 with welded seams 903 to protect internal components from moisture, dirt and vandalism. Sheet metal enclosure 901 is shaped to provide a 5-degree back-angle tilt to the faceplate 907 . This angle assists in viewing LCD 904 as well as providing a gravitational vector that assists the seating of disks in carousel 950 . Enclosure 901 has a flat bottom to allow for counter-top installation, and a sloped top to discourage customers from placing objects on the kiosk. Kiosk 200 , FIG. 2 , runs without an external cooling fan and mounts easily on a wall, thru a wall, on a countertop, or on a pedestal. Enclosure 901 serves as a “heat sink” to radiate heat from heat-generating inner components, such as a computer 612 , and drive motors (described in more detail below). Housing 900 also has a full-length side piano hinge 905 to protect the kiosk from vandalism and contamination. A cast main faceplate 907 serves as the front of housing 900 and provides a mechanically stable platform for the working elements of kiosk 200 ; it also serves to deter penetration by vandals. The remaining seam 909 between faceplate 907 and enclosure 901 is baffled and gasketed to protect against penetration by mechanical means or by dust or liquids.
[0089] FIG. 9 shows a perspective view of electro-mechanical elements that are internal to housing 900 . A carousel 950 that rotates to dispense optical disks holds 102 cases; carousel 950 is lightweight and easy to fabricate using interlocking aluminum extrusion. The extrusions after assembly are jigged and welded to minimize run-out and to assure stability. Carousel 950 is preferably driven by chain drive 952 to ensure “no-slip” operation. An eject mechanism 954 dispenses optical recorded media from housing 900 , through input/output slot 940 ; mechanism 954 connects to faceplate 907 by two mechanical screws. One cable (not shown) serves to power and control mechanism 954 , via the internal computer and connected power. A servo-controller and RS232-485 converter 956 drives the carousel motor 958 . Carousel drive motor 958 may, for example, mount within housing 900 by three mechanical screws; two cables generally connect to motor 958 to provide power and electrical control.
[0090] FIG. 10 shows further detail of internal mechanics of kiosk 200 , FIG. 2 , within enclosure 900 , FIG. 8 . A spindle assembly 960 holds carousel 950 for rotation thereon. FIG. 11 shows a perspective view of carousel 950 alone. Each slot 951 of carousel 950 holds one optical media disk within a case, described in more detail below. Carousel 950 has a central hub 953 for mounting on spindle assembly 960 . Carousel 950 is removed from spindle assembly 960 by three mechanical screws (not shown). FIG. 10 also shows a more detailed view of speakers 962 , providing audible tones, music and communications to users of kiosk 200 . Speakers 962 for example may be audio device 212 of kiosk 200 , FIG. 2 .
[0091] FIG. 12 shows an encoder 970 that is used by kiosk 200 to accurately position carousel and spindle 950 , 960 . The standoffs 972 act as supports and as preload springs for drive chain 952 . A sprocket 974 drives chain 952 and, thereby, carousel 950 . Gear motor 958 provides the torque and speed to accurately position carousel 950 .
[0092] FIG. 13 shows further detail of mechanical components within housing 900 . The gear motor 959 rotates cam 980 to move eject arm 976 in and at a controlled speed and position. Optical sensors 978 provide feedback with motor 959 to accurately position eject arm 976 in the “Out” position (i.e., clear for carousel rotate) and in the “In” position (i.e., arm 976 is in position for kiosk 200 to sense an incoming case). A flag 992 trips optical sensors 978 above. An optical sensor 982 provides additional feedback indicating that an eject maneuver is in fully ejected position; a flag 988 trips optical sensor 982 in performing this function. An optical sensor 984 picks up a flag on carousel 950 as a home reference for carousel position. The offset value is adjusted in operating software. A reflective optical sensor 986 senses the presence of a case in a slot 951 , FIG. 11 . A mechanical switch 990 senses a case during a return to a slot 951 . Eject arm 976 supports mechanical case switch 990 and pushes a case into the input/output rollers (described below) during an eject cycle.
[0093] FIG. 14 shows additional features of a kiosk of the invention, including internal electro-optical and electro-mechanical components to facilitate the operations herein. FIG. 14 specifically shows these components used in conjunction with the input/output slot 940 , FIG. 8 . A digital camera 1000 couples to a mount 1002 , as shown. One suitable camera for camera 1000 is a 3Com 00371800 HomeConnect PC Digital Camera. Camera 1000 captures an image approximately 1.6″ in diameter, through its illustrative field of view 1003 . This image is then processed by the internal kiosk computer (e.g., computer 612 , FIG. 6 ) to assess barcodes, patterns and/or characters on a disk 700 , FIG. 7 . A special pattern may be placed on optical media label 702 and next to barcodes 701 to deter fraud. Barcodes 701 captured by camera 1000 as a digital image can be decoded at various angles. The image is stored locally or at the core server 103 , FIG. 1 , for post processing should an issue arise regarding a related transaction. Illumination for camera 1000 in capturing the digital image is through active illumination (e.g., a light). A gear motor 1004 provides the torque and speed to accurately position a case in or out of a slot 951 . A gear motor 1006 provides the torque and speed to accurately drive a cam that operates the door, door lock and pinch rollers (discussed below).
[0094] FIG. 15 shows additional features of a kiosk of the invention, including internal electro-optical and electro-mechanical components to facilitate the operations herein. FIG. 15 specifically shows these components used in conjunction with the input/output slot 940 , FIG. 8 . A ridge 1012 provides relief for the post machining of cast main plate 907 , and further provides a reference for gasketing and a shield against mechanical penetration. Cable routing apertures 1014 facilitate cable connections through bezel 920 ; cable routing apertures 1015 facilitate cable connections through main plate 907 . Drive gears 1016 rotate the intake/output rollers 1018 . A pair of case glides 1020 physically guides a case into and out of kiosk 200 .
[0095] FIG. 16 shows additional detail of the input and output mechanism of kiosk 200 . The pinch rollers 1030 force a case through guides 1020 against the intake/output rollers 1018 , FIG. 15 , and also set the case during a return. A door 1032 prevents an unauthorized case or object from entering the kiosk and shields inventory when carousel 950 is rotating. The case sensors 1034 determine whether a case is valid to trigger an image read by camera 1000 , FIG. 14 . The activation sequence of sensors 1034 is used to determine if a case is removed prematurely during a return cycle or if a case is adequately ejected during an output cycle. The case sensor LEDs 1036 provide the operating light for case sensors 1034 . Optical sensors 1038 provide the feedback required to position camshaft 1048 ( FIG. 17 ). Sensor 1038 (a “door closed” sensor) may be used to show when door 1032 is fully closed so that carousel 950 can be safely rotated with a clear doorway. A door lock 1040 automatically latches and locks door 1032 as soon as a case clears the doorway during either an input or output cycle.
[0096] FIG. 17 shows additional features of a kiosk of the invention, including internal electro-optical and electro-mechanical components to facilitate the operations herein. FIG. 17 specifically shows these components used in conjunction with the input/output slot 940 , FIG. 8 . A flag 1042 trips “door closed” sensor. A door cam 1033 operates to open and close door 1032 . A door lock cam 1044 operates the door lock 1040 . A gear 1046 drives camshaft 1048 for cams 1033 , 1044 , and 1052 . Three flags 1050 position cam shaft 1048 in following four distinct positions:
[0097] Door 1032 closed and lockable; pinch rollers 1030 open
[0098] Door 1032 open and unlocked; pinch rollers 1030 open
[0099] Door 1032 open; pinch rollers 1030 closed
[0100] Door 1032 closed and locked; pinch rollers 1030 closed
[0101] Two pinch roller cams 1052 move pinch rollers 1030 to closed and open positions.
[0102] FIG. 18 shows a front view of carousel 950 . Carousel 950 is preferably extruded as a series of parts shown in detail within FIGS. 19-22 . FIG. 19 shows the center extrusion hub 950 a . FIG. 20 shows the inner ring extrusion 950 b . FIG. 21 shows the spoke extrusion 950 c . FIG. 22 shows the outer ring extrusion 950 d . Carousel 950 is thus extruded in three main sections: (1) the center extrusion hub 950 a has the inside portion 1200 of the disk alignment fins and slots for the spoke extrusions 950 c ; (2) the spoke extrusions 950 c are notched at 1202 to align with the slots in the center extrusion hub 950 a and ring extrusions 950 b , 950 d ; and (3) outer ring extrusion 950 d contains outside disk alignment fins 1204 and is also slotted at 1206 to accept spoke extrusions 950 c . The finished outer ring extrusion consists of six sections 950 d welded together with six spoke extrusions 950 c to complete carousel 950 .
[0103] FIG. 23 shows an inside view of one case 1100 suitable for housing optical recorded media for input and output with a kiosk 100 such as described in connection with FIGS. 8-17 . FIG. 24 shows an outside view of case 1100 . FIG. 7 shows case 1100 in a closed position, housing disk 700 . FIG. 25 illustrates case operation through intake slot 940 . A disk 700 sits within insert molds 1102 and around central hub 1104 . Case 1100 has a hole 1106 used by sensors 1034 to detect whether case 1100 is suitably keyed for kiosk 200 , FIG. 2 . Intake Slot 940 is shaped to align case 1100 with sensors 1034 , FIG. 16 , in the kiosk intake housing. An example of keying is as follows: one sensor 1034 A is aligned with hole 1106 , providing an “open position”, and the 2nd sensor 1034 B is blocked by the case 1100 in a “closed position”. Arrows 1130 indicate common direction for the case 1100 inserted into slot 940 .
[0104] In operation, the intake mechanisms of kiosk 200 preferably operate according to the following steps:
[0105] After dispensing a disk, carousel 950 , FIG. 11 , is rotated such that an available return position is adjacent the input/output slot 940 , FIG. 8 ; the return position being a slot 951 that does not contain a disk 700 .
[0106] To initiate a return, a “return rental” button is triggered at the touch screen display 904 , FIG. 8 .
[0107] A disk 700 within a case 1100 is inserted into the intake slot 940 , FIG. 8 , until it reaches a door stop 1032 ; at this position, sensors 1034 on case 1100 are read to activate the barcode scanning process.
[0108] Barcode 701 , FIG. 7 , is read: the barcode image is scanned to acquire the appropriate code response; if the code is not acquired, the image is rotated 30 o and is re-scanned; this cycle is repeated until the codes are acquired, or for a maximum of three cycles. Once the code is decoded, bar code 701 A, FIG. 7 , is read to determine which group code disk 700 is associated with; if cleared, kiosk door 1032 , FIG. 16 , is opened by rotating cam shaft 1048 . The group code 701 A identifies the disk as originating from a specific “kiosk group”. Door 1032 is opened if the kiosk is associated with the group code. Concurrently, the kiosk reads a serialized code from bar code 701 B to identify the individual disk 700 and to register it with the disk inventory database. The inventory database information is eventually relayed to core server 103 , FIG. 1 .
[0109] If a disk is accepted, the cam motor rotates camshaft 1048 to unblock door 1032 and then to clamp rollers 1018 , FIG. 15 , onto the case. The intake roller motor is activated to pull the case into a carousel slot 951 . The camshaft continues to rotate to prep the door block spring. At the end of the intake motion, the case clears the door and allows the door block spring to move the intake block into a closed position. The intake rollers complete the transport of the disk into a free carousel slot 951 .
[0110] A rear slot sensor 986 , FIG. 13 , verifies the existence of a case in the slot and sensor 990 verifies the completed transport of the case through the intake rollers 1018 , FIG. 15 , and into carousel 950 .
[0111] A transaction finishes with the insertion of the serialized disk information into database tables.
[0112] In operation, kiosk 200 has a resting state that performs the following steps:
[0113] Door 1032 is locked.
[0114] Eject arm 976 , FIG. 13 , is in a read position.
[0115] Carousel 950 is held at an open slot 951 .
[0116] Rollers 1018 are opened.
[0117] In operation, kiosk 200 preferably operates to accept returns (e.g., recorded disk media 700 , FIG. 7 , in a case 1100 , FIGS. 23-24 ) according to the following sequential steps and/or states:
[0118] Kiosk 200 is in a resting state.
[0119] A return-rental button is triggered by a user of the kiosk, by pressing a graphical representation of the button on touch screen 904 . The return-rental button triggers activation of the light for camera 1000 .
[0120] A user inserts a disk 700 , within a case 1100 , to slot 940 .
[0121] Kiosk case sensor reads case 1100 .
[0122] Kiosk reads disk bar code 701 .
[0123] Kiosk rollers 1018 close.
[0124] Kiosk door 1032 opens.
[0125] Intake roller 1018 on.
[0126] Door 1032 ready to close.
[0127] Case-in switch 990 read.
[0128] Rollers 1018 stop.
[0129] Door 1032 closes and locks.
[0130] Eject arm 976 retracts.
[0131] Carousel 950 moves to open position.
[0132] Rollers 1018 open.
[0133] Eject arm 976 moves to read position.
[0134] Kiosk in resting state.
[0135] In operation, kiosk 200 preferably operates in a rental transaction according to the following sequential steps and/or states:
[0136] Kiosk in resting state.
[0137] Sensors 1034 A and 1034 B checked for intake blockage.
[0138] Eject arm 976 retracts.
[0139] Carousel 950 moves to position.
[0140] Door 1032 opens.
[0141] Disk 700 ejected.
[0142] Rollers 1018 close.
[0143] Output roller 1018 on.
[0144] Disc 700 in case 1100 removed.
[0145] Door 1032 closes and locks
[0146] Carousel 950 moves to open slot 951 .
[0147] Eject arm 976 moves to read position.
[0148] Kiosk 200 in resting state
[0149] The above is a description of a method and system for Internet-based automated disk distribution and retrieval. It is expected that others will design alternative methods and systems for Internet-based disk distribution using stand-alone automated kiosks as set forth in the claims below either literally of through the Doctrine of Equivalents. | A kiosk dispenses and receives recorded optical media using an interconnected central server, through an Internet Service Provider. The central server has databases and processing capabilities and is connected to a credit verification system. The databases collect inventory administration information and customer data (e.g., credit card information and email addresses) from the kiosks. The central server initiates credit verification, sends receipts to customers via email and maintains databases for remote inventory control and administration of the kiosk network. A kiosk may identify a recorded disk for automated restocking and perform quality assessment of a recorded disk. The kiosk may provide publishing-on-demand or act as a portal for remotely served advertisements. The kiosk preferably includes a rotatable carousel with a selection of DVDs. A digital camera captures a digital image of a disk barcode and internal software rotates the image to “read” the barcode, to control inventory and access issues. | 6 |
FIELD OF THE INVENTION
The present invention relates to secondary cells which comprise a cell can and an electrode unit accommodated in the cell can and serving as a secondary cell element and which are adapted to deliver electric power generated by the electrode unit from a pair of electrode terminals on the can to the outside.
BACKGROUND OF THE INVENTION
In recent years, attention has been directed to lithium ion secondary cells or batteries having a high energy density for use as power sources for portable electronic devices, electric vehicles, etc. Cylindrical lithium ion secondary cells of relatively large capacity, for example, for use in electric vehicles comprise, as shown in FIG. 5, a cylindrical cell can 1 having a cylinder 11 and lids 12 , 12 fixed to the respective ends of the cylinder, and a rolled-up electrode unit 2 encased in the can 1 .
A pair of positive and negative electrode terminal assemblies 40 , 40 are attached to the lids 12 , 12 , respectively. The two electrodes of the rolled-up electrode unit 2 are connected to the terminal assemblies 40 , 40 , whereby the electric power generated by the electrode unit 2 can be delivered to the outside from the pair of terminal assemblies 40 , 40 . Each lid 12 has a screw plug 14 screwed in and closing a threaded bore 18 for pouring an electrolyte into the cell can 1 therethrough and a gas vent valve 13 closing a gas vent 17 .
As shown in FIG. 6, the rolled-up electrode unit 2 comprises a positive electrode 21 and a negative electrode 23 which are each in the form of a strip and which are rolled up into a spiral form with a striplike separator 22 interposed between the electrodes. The positive electrode 21 comprises a striplike current collector 25 in the form of aluminum foil and coated over opposite surfaces thereof with a positive electrode active substance 24 comprising a lithium composite oxide. The negative electrode 23 comprises a striplike current collector 27 in the form of copper foil and coated over opposite surfaces thereof with a negative electrode active substance 26 containing a carbon material. The separator 22 is impregnated with a nonaqueous electrolyte.
The positive electrode 21 has an uncoated portion having no active substance 24 applied thereto, and base ends of current collector tabs 3 are joined to the uncoated portion. Similarly, the negative electrode 23 has an uncoated portion having no active substance 26 applied thereto, and base ends of current collector tabs 3 are joined to the uncoated portion.
With reference to FIG. 5, the current collector tabs 3 of the same polarity have outer ends connected to one electrode terminal assembly 40 . For the sake of convenience, FIG. 5 shows only some of the electrode tabs as connected at their outer ends to the terminal assembly 40 , with the connection of the other tab outer ends to the assembly 40 omitted from the illustration.
The electrode terminal assembly 40 comprises an electrode terminal member 9 extending through and attached to the lid 12 of the cell can 1 . The terminal member 9 comprises a screw shank 92 extending through a hole in the lid 12 , a flange 91 formed at a base end of the shank 92 and projecting into the can 1 , and a square projection 93 at an outer end of the shank.
A tubular insulating seal member 8 is fitted in the hole of the lid 12 , while a disklike insulating seal member 81 is provided on the surface of the lid 12 . O-rings 82 , 83 are interposed between opposed faces of the tubular insulating seal member 8 and the flange 91 of the terminal member 9 and between opposed faces of the tubular insulating seal member 8 and the lid 12 . Thus, electrical insulation and a seal are provided between the lid 12 and the terminal member 9 . The insulating seal members 8 , 81 are made of polypropylene.
A washer 71 and a spring washer 72 are provided around the shank 92 of the electrode terminal member 9 from outside the lid 12 , and a nut 7 is screwed on the shank 92 . The seal members 8 , 81 and the O-rings 82 83 are held between the flange 91 of the terminal member 9 and the washer 71 by tightening up the nut 7 to produce an enhanced sealing effect. A tab connecting screw member 41 is screwed in the flange 91 of the terminal member 9 . The outer ends of the current collector tabs 3 extending from the rolled-up electrode unit 2 are held between the flange 91 and the screw member 41 .
In assembling the conventional cylindrical secondary cell described, the electrode terminal assembly 40 is mounted on the lid 12 of the cell can 1 , and the nut 7 is thereafter screwed on the terminal member 9 . However, this procedure involves a likelihood that the terminal member 9 will rotate with the rotation of the nut 7 . It is therefore impossible to tighten up the nut 7 with full strength, entailing the problem of increased contact resistance.
In attaching the electrode terminal assembly 40 to the lid 12 before the lid 12 is fixed to the cylinder 11 , the flange 91 of the terminal member 9 can be held against rotation with a tool and thereby prevented from rotating with the nut 7 , whereby the damage to the current collector tabs 3 is avoidable. For example, with cylindrical secondary cells for use in electric vehicles, however, the nut 7 is likely to become loosened due to an influence of vibration. Since the nut 7 then needs to be tightened up to a greater extent, there arises the problem that the terminal member 9 will rotate with the nut 7 similarly.
Accordingly, a secondary cell is proposed wherein the electrode terminal assembly and the lid are fixed to each other with a rotation preventing pin [JP-B No. 9-92238(1997)], whereas the proposal additionally requires an insulating member for electrically insulating the pin from the terminal assembly, giving rise to the problem of increasing the number of components. Further since there is a need to weld the pin and the lid to each other, another problem is encountered in that an increased number of manufacturing steps entails a higher cost.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a secondary cell wherein an electrode terminal member can be prevented from rotating with another member when an electrode terminal assembly is fixed to a lid without the likelihood of increasing the number of components or the number of manufacturing steps.
The present invention provides a secondary cell which comprises an electrode unit 2 enclosed in a cell can 1 and serving as a cell element and which is adapted to deliver electric power generated by the electrode unit 2 to the outside via a pair of electrode terminal portions. At least one of the electrode terminal portions is provided by an electrode terminal assembly 4 attached to the cell can 1 . The electrode terminal assembly 4 comprises:
an electrode terminal member 5 extending through a center hole 19 formed in the cell can 1 and having a flange 51 projecting into the cell can 1 and a screw shank 52 projecting outward from the cell can 1 ,
an insulating seal member 6 provided in the center hole 19 of the cell can 1 around the screw shank 52 of the electrode terminal member 5 for providing electrical insulation and a seal between the cell can 1 and the electrode terminal member 5 , and
a nut 7 screwed on the screw shank 52 of the electrode terminal member 5 from outside the cell can 1 ,
the insulating seal member 6 being in engagement with the cell can 1 and the flange 51 of the electrode terminal member 5 and nonrotatable relative to the cell can and the flange.
With the electrode terminal assembly 4 attached to the cell can 1 in providing the secondary cell of the invention, the nut 7 is screwed on the screw shank 52 of the electrode terminal member 5 by rotating the nut 7 , whereby the insulating seal member 6 is clamped between the flange 51 of the electrode terminal member 5 and the nut 7 . The terminal assembly 4 is therefore fixed to the cell can 1 , and the insulating seal member 6 produces a satisfactory sealing effect.
In rotating the nut 7 , the torque on the nut 7 is delivered to and received by the terminal member 5 . Because the flange 51 of the terminal member 5 is in engagement with the seal member 6 and nonrotatable relative thereto, and further because the seal member 6 is engagement with the cell can 1 and nonrotatable relative thereto, the torque acting on the terminal member 5 is received by the cell can 1 . The terminal member 5 is therefore unlikely to rotate with the nut 7 .
Since there is no need to use any special member for preventing the rotation of the electrode terminal member 5 , there is no increase in the number of components, and the electrode terminal assembly 4 is simple in construction. Moreover, the insulating seal member 6 can be integrally molded from resin easily like the conventional insulating seal member, while the present cell can be assembled by the same number of steps as in the prior art and is easy to produce.
Stated more specifically, the engaging portions of the insulating seal member 6 and each of the cell can 1 and the flange 51 of the electrode terminal member 5 are provided with a pair of engaging faces in engagement with each other nonrotatably. With this construction, three members conventionally in use, i.e., the cell can 1 , electrode terminal member 5 and insulating seal member 6 , are given a structure for preventing the rotation of the terminal member 5 , so that the present invention can be embodied using the same components as in the prior art.
Further stated more specifically, the insulating seal member 6 is provided with a center bore 64 having the screw shank 52 of the electrode terminal member 5 inserted therethrough, and has two peripheral walls formed around the center bore 64 and each varying in radial distance from a center of the center bore 64 along the direction of periphery of the wall, the cell can 1 having a peripheral wall in engagement with one of the peripheral walls of the insulating seal member 6 nonrotatably relative thereto, the flange 51 of the electrode terminal member 5 having a peripheral wall in engagement with the other peripheral wall of the insulating seal member 6 nonrotatably relative thereto. With this specific construction, one of the peripheral walls of the insulating seal member 6 and the peripheral wall of the cell can 1 provide a pair of engaging faces which are nonrotatable relative to each other, and the other peripheral wall of the seal member 6 and the peripheral wall of flange 51 of the terminal member 5 provide another pair of engaging faces which are nonrotatable relative to each other.
Further stated more specifically, the insulating seal member 6 comprises a plate body 60 , and the plate body 60 has an outer peripheral wall provided with at least one corner portion formed by the intersection of a plane with another plane, the outer peripheral wall providing one of said two peripheral walls of the seal member 6 . The corner portion formed on the plate body 60 of the seal member 6 is then effectively in engagement with the peripheral wall of the cell can 1 , whereby the seal member 6 is reliably prevented from rotating relative to the cell can 1 . Further because the two peripheral walls of the seal member 6 can be spaced apart by an increased distance, the seal member 6 can be given an increased strength, consequently acting to prevent the rotation of the electrode terminal member 5 more effectively.
Further stated more specifically, the flange 51 of the electrode terminal member 5 is provided with an outer peripheral wall having a cylindrical face partly replaced by planar faces, and the insulating seal member 6 is provided with an engaging recessed portion 62 for the outer peripheral wall of the flange 51 of the electrode terminal member 5 to engage in nonrotatably relative thereto, the engaging recessed portion 62 having an inner peripheral wall providing the other of said two peripheral walls of the seal member 6 . The flange 51 of the terminal member 5 and the engaging recessed portion 62 of the insulating seal member 6 are then easy to make, while the rotation of the terminal member 5 can be reliably prevented when the terminal member 5 is to be fixed.
Further stated more specifically, the flange 51 of the electrode terminal member 5 is provided with an outer peripheral wall having at least one corner portion formed by the intersection of a plane with another plane, and the insulating seal member 6 is provided with an engaging recessed portion 62 for the outer peripheral wall of the flange 51 of the electrode terminal member 5 to engage in nonrotatably relative thereto, the engaging recessed portion 62 having an inner peripheral wall providing said other peripheral wall. The corner portion on the flange 51 of the terminal member 5 is then effectively engaged in the recessed portion 62 of the insulating seal portion 6 , whereby the terminal member 5 is reliably prevented from rotating relative to the seal member 6 . Consequently, the rotation of the terminal member 5 can be reliably prevented when the terminal member 5 is fixed.
Thus, the secondary cell of the present invention is so adapted that the electrode terminal member 5 can be prevented from rotating with the nut 7 when the electrode terminal assembly is fixed to the lid 12 , without entailing any increase in the number of components or the number of manufacturing steps.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary sectional view of a cylindrical lithium ion secondary cell embodying the invention;
FIG. 2 is an exploded front view partly broken away and showing an electrode terminal assembly;
FIG. 3A is an exploded perspective view of a lid, insulating seal member and electrode terminal member;
FIG. 3B is an exploded perspective view of a lid, insulating seal member and electrode terminal member according to another embodiment;
FIG. 4 is a perspective view of a module battery;
FIG. 5 is a fragmentary sectional view of a cylindrical lithium ion secondary cell of the prior art; and
FIG. 6 is a perspective view partly in development and showing a rolled-up electrode unit.
DETAILED DESCRIPTION OF EMBODIMENTS
Cylindrical lithium ion secondary cells embodying the present invention will be described below in detail with reference to the drawings. With reference to FIG. 1, the secondary cell of the invention comprises a cylindrical aluminum cell can 1 including a cylinder 11 and lids 12 welded to opposite opening portions of the cylinder, and a rolled-up electrode unit 2 accommodated in the cell can 1 . The cell can 1 is 57 mm in outside diameter and 220 mm in length. The rolled-up electrode unit 2 has the same construction as the conventional one shown in FIG. 6 and therefore will not be described again.
An electrode terminal assembly 4 is attached to each lid 12 constituting the cell can 1 . As in the prior art, the lid 12 has a screw plug 14 screwed in and closing a threaded bore 18 for pouring an electrolyte into the cell can 1 therethrough and a gas vent valve 13 closing a gas vent 17 .
A plurality of current collector tabs 3 of the same polarity extending from the rolled-up electrode unit 2 have outer ends connected to the electrode terminal assembly 4 . For the sake of convenience, FIG. 1 shows only some of the electrode tabs as connected at their outer ends to the terminal assembly 4 , with the connection of the other tab outer ends to the assembly 4 omitted from the illustration.
As shown in FIGS. 1 and 2, the electrode terminal assembly 4 comprises an electrode terminal member 5 extending through a center hole 19 in the lid 12 and attached to the lid 12 . The terminal member 5 comprises a screw shank 52 extending through the center hole 19 of the lid 12 , a flange 51 formed at a base end of the shank 52 and projecting into the can 1 , and a square projection 53 at an outer end of the shank projecting outward from the cell can 1 . A tubular insulating seal member 6 is fitted in the center hole 19 of the lid 12 , while a disklike insulating seal member 61 is provided along the opening edge of the hole 19 . O-rings 82 , 83 are interposed between opposed faces of the tubular insulating seal member 6 and the flange 51 of the terminal member 5 and between opposed faces of the tubular insulating seal member 6 and the lid 12 to provide electrical insulation and a seal between the lid 12 and the terminal member 5 .
The electrode terminal member 5 of the positive electrode terminal assembly 4 is made of aluminum, while the terminal member 5 of the negative electrode terminal assembly 4 is made of nickel. In either of the terminal assemblies 4 , the insulating seal members 6 , 61 are made of polypropylene, and the O-rings 82 , 83 are made of fluorocarbon resin.
A washer 71 and a spring washer 72 are provided around the shank 52 of the electrode terminal member 5 from outside the lid 12 , and a nut 7 is screwed on the shank 52 . The seal members 6 , 61 and the O-rings 82 83 are clamped between the flange 51 of the terminal member 5 and the washer 71 by tightening up the nut 7 to produce an enhanced sealing effect. A tab connecting screw member 41 is screwed in the flange 51 of the terminal member 5 . The outer ends of the current collector tabs 3 extending from the rolled-up electrode unit 2 are held between the flange 51 and the screw member 41 .
With reference to FIG. 3A, the insulating seal member 6 of the electrode terminal assembly 4 comprises a rectangular plate body 60 , and a cylindrical portion 63 having a center bore 64 and upwardly projecting from the plate body 60 centrally thereof. The plate body 60 has an engaging recessed portion 62 resembling an ellipse, formed in the rear side thereof and having an inner periphery in the form of a cylindrical face partly replaced by planar faces. On the other hand, formed in the rear side of the lid 12 is a rectangular engaging recessed portion 16 which is centered about the center hole 19 and in which the plate body 60 of the insulating seal member 6 is engageable. The flange 51 of the terminal member 5 has a contour resembling an ellipse so as to be engageable in the recessed portion 62 formed in the plate body 60 of the seal member 6 .
In rotating the nut 7 for tightening up after the electrode terminal assembly 4 has been attached to the lid 12 as seen in FIG. 1, the torque of the nut 7 is delivered to the electrode terminal member 5 . Because the flange 51 of the terminal member 5 is in engagement with the insulating seal member 6 and nonrotatable relative thereto and further because the seal member 6 is in engagement with the lid 12 and nonrotatable relative thereto, the terminal member 5 is prevented from rotating. In this way, the terminal member 5 is prevented from rotating with the nut 7 being tightened up, so that sufficient tightening torque can be given to the nut 7 to result in reduced contact resistance.
The cylindrical lithium ion secondary cell of the invention has the lid 12 , insulating seal member 6 and electrode terminal member 5 which are shown in FIGS. 1 to 3 A, in place of the lid 12 , insulating seal member 8 and electrode terminal member 9 which are incorporated in the cylindrical lithium ion secondary cell of the prior art shown in FIG. 5 . According to the present invention, the rotation of the terminal member 5 is prevented by forming the rectangular recessed portion 16 in the lid 12 , the elliptical flange 51 on the terminal member 5 , and the rectangular plate body 60 and recessed portion 62 in the insulating seal member 6 . This results in no increase in the number of components or the number of manufacturing steps. Moreover, the cylindrical lithium ion secondary cell of the invention can be assembled easily by exactly the same process as in the prior art.
The engaging structure of lid 12 , seal member 6 and terminal member 5 shown in FIG. 3A is not limitative; also usable is, for example, the engaging structure shown in FIG. 3 B. With reference to FIG. 3B, the insulating seal member 6 comprises a rectangular plate body 60 , and a cylindrical portion 63 having a center bore 64 and projecting upward from the plate body 60 centrally thereof. A rectangular engaging recessed portion 62 is formed in the rear side of the plate body 60 . The flange 51 of the electrode terminal member 5 has a contour resembling a rectangular plate so as to be engageable in the recessed portion 62 formed in the plate body 60 of the seal member 6 . Like the engaging arrangement shown in FIG. 3A, this engaging arrangement is also effective for preventing the terminal member 5 from rotating with the nut 7 .
To substantiate the effect of the electrode terminal assembly 4 of the invention for preventing the rotation of the terminal member 5 , the cell of the invention shown in FIG. 1 and the conventional cell shown in FIG. 5 were assembled by tightening up the nut 7 for the invention cell of FIG. 1 with torque of 80 kgf·cm by a torque wrench, and tightening up the nut 7 for the conventional cell of FIG. 5 by a torque wrench until the electrode terminal member 9 started to rotate with the nut. The final tightening-up torque for the conventional cell was 40 kgf·cm.
Module batteries comprising four cells 10 as shown in FIG. 4 were each assembled using cells of the invention or conventional cells fabricated in this way. The four cells 10 were connected to one another in series using connectors 15 as held between the spring washer 72 and the nut 7 . The module battery of the invention and the module battery of the prior art were checked for resistance value by a 1-kHz a.c. ohmmeter.
The module battery of the invention was 9.3 mΩ in resistance value, while the module battery of the prior art was 15.6 mΩ in resistance value. This difference can be explained as follows. With the cell of the invention, the terminal member 5 is in engagement with the lid 12 nonrotatably relative thereto, so that sufficient tightening-up torque can be given to result in reduced contact resistance, whereas with the conventional cell wherein the terminal member 9 rotates with the nut, it is impossible to give sufficient tightening-up torque to result in increased contact resistance.
The cell of the invention is not limited to the foregoing embodiments in construction but can be modified variously by one skilled in the art without departing from the spirit of the invention as set forth in the appended claims. For example, seal packing sheets are usable in place of the O-rings 82 , 83 . The means of engagement between the lid 12 and the insulating seal member 6 , and the means of engagement between the seal member 6 and the electrode terminal member 5 are not limited to the rectangular or elliptical structure shown in FIG. 3A or 3 B, but it is possible to use engaging means including a pair engageable faces of various shapes insofar as these faces are engageable nonrotatably relative to each other. | In a secondary cell comprising an electrode unit enclosed in a cell can and adapted to deliver electric power generated by the electrode unit via electrode terminal assemblies, each electrode terminal assembly comprises an electrode terminal member extending through a center hole in a lid of the can, an insulating seal member provided in the center hole of the lid around a screw shank of the electrode terminal member, and a nut screwed on the screw shank of the electrode terminal member projecting outward from can. The insulating seal member is in engagement with the can and the flange of the electrode terminal member and nonrotatable relative to the cell can and the flange, whereby the electrode terminal member is prevented from rotating with the nut when the electrode terminal assembly is fixed to the lid. | 7 |
PRIORITY
The present application is a continuation of U.S. patent application Ser. No. 09/993,779, filed Nov. 5, 2001 now U.S. Pat. No. 7,830,630; which claims the benefit of U.S. Provisional Patent Application Ser. No. 60/301,490, filed Jun. 28, 2001, now expired; all of the foregoing applications are incorporated by reference herein in their entireties.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is related to commonly owned U.S. patent application Ser. Nos. 09/993,877 entitled “DATA-STORAGE DISK HAVING FEW OR NO SPIN-UP WEDGES AND METHOD FOR WRITING SERVO WEDGES ONTO THE DISK,” 09/993,876 entitled “CIRCUIT AND METHOD FOR DETECTING A SERVO WEDGE ON SPIN UP OF A DATA-STORAGE DISK”, “09/993,869 entitled “CIRCUIT AND METHOD FOR DETECTING A SPIN-UP WEDGE AND A CORRESPONDING SERVO WEDGE ON SPIN UP OF A DATA-STORAGE DISK”, 09/994,009 entitled “A DATA CODE AND METHOD FOR CODING DATA”, 09/993,986 entitled “CIRCUIT AND METHOD FOR DEMODULATING A SERVO POSITION BURST”, 09/993,778 entitled “SERVO CIRCUIT HAVING A SYNCHRONOUS SERVO CHANNEL AND METHOD FOR SYNCHRONOUSLY RECOVERING SERVO DATA,” which were filed on the same day as the present application and which are incorporated by reference.
TECHNICAL FIELD
The present disclosure is related generally to recovering data, and more particularly to a circuit and method for detecting the phase of a servo signal so that a servo circuit can compensate for a reverse-connected read head.
BACKGROUND
As computer-software applications become larger and more data intensive, disk-drive manufacturers often increase the data-storage capacities of data-storage disks by increasing the density of the stored servo and application data.
To increase the accuracy of a servo circuit as it reads the denser servo data from a data-storage disk, the manufacturer often codes the servo data. For example, as discussed below in conjunction with FIG. 4 , the manufacturer may use a Gray code to code the servo data.
Unfortunately, if the manufacturer codes the servo data stored on a data-storage disk, then a disk drive that incorporates the disk often cannot incorporate conventional techniques—such as NRZ (Non Return to Zero)-NRZI (Non Return to Zero Interleave)-NRZ conversion—to compensate for a reverse-connected read head.
FIG. 1 is a plan view of a conventional disk drive 10 , which includes a magnetic data-storage disk 12 , a read-write head 14 , an arm 16 , and a voice-coil motor 18 . The disk 12 is partitioned into a number—here eight—of disk sectors 20 a - 20 h , and includes a number—typically in the tens or hundreds of thousands—of concentric data tracks 22 a - 22 n . Readable-writable application data is stored in respective data sectors (not shown) within each track 22 . Under the control of the disk drive's head-position circuit (not shown in FIG. 1 ), the motor 18 moves the arm 16 to center the head 14 over a selected track 22 .
Referring to FIG. 2 , conventional data servo wedges 24 —only servo wedges 24 a - 24 c are shown—include servo data that allows the head-position circuit (not shown in FIG. 2 ) of the disk drive 10 ( FIG. 1 ) to accurately position the read-write head 14 ( FIG. 1 ) during a data read or write operation. The servo wedges 24 are located within each track 22 at the beginning—the disk 12 spins counterclockwise in this example—of each disk sector 20 . Each servo wedge 24 includes respective servo data that identifies the location (track 22 and sector 20 ) of the servo wedge. Thus, the head-position circuit uses this servo data to position the head 14 over the track 22 selected to be read from or written to. The manufacturer of the disk drive 10 typically writes the servo wedges 24 onto the disk 12 before shipping the disk drive to a customer; neither the disk drive nor the customer alters the servo wedges 24 thereafter. Servo wedges like the servo wedges 24 are further discussed below in conjunction with FIG. 3 and in commonly owned U.S. patent application Ser. No. 09/783,801, filed Feb. 14, 2001, entitled “VITERBI DETECTOR AND METHOD FOR RECOVERING A BINARY SEQUENCE FROM A READ SIGNAL,” which is incorporated by reference.
FIG. 3 is a diagram of the servo wedge 24 a of FIG. 2 , the other servo wedges 24 being similar. Write splices 30 a and 30 b respectively separate the servo wedge 24 a from adjacent data sectors (not shown). An optional servo address mark (SAM) 32 indicates to the head-position circuit (not shown in FIG. 3 ) that the read-write head 14 ( FIG. 1 ) is at the beginning of the servo wedge 24 a . A servo preamble 34 allows the servo circuit (not shown in FIG. 3 ) of the disk drive 10 ( FIG. 1 ) to synchronize the sample clock to the servo signal ( FIG. 5 ), and a servo synchronization mark (SSM) 36 identifies the beginning of a head-location identifier 38 . The preamble 34 and SSM 36 are discussed in commonly owned U.S. patent application Ser. Nos. 09/993,877 entitled “DATA-STORAGE DISK HAVING FEW OR NO SPIN-UP WEDGES AND METHOD FOR WRITING SERVO WEDGES ONTO THE DISK,” 09/993,876 entitled “CIRCUIT AND METHOD FOR DETECTING A SERVO WEDGE ON SPIN UP OF A DATA-STORAGE DISK”, 09/993,869 entitled “CIRCUIT AND METHOD FOR DETECTING A SPIN-UP WEDGE AND A CORRESPONDING SERVO WEDGE ON SPIN UP OF A DATA-STORAGE DISK”, 09/993,778 entitled “SERVO CIRCUIT HAVING A SYNCHRONOUS SERVO CHANNEL AND METHOD FOR SYNCHRONOUSLY RECOVERING SERVO DATA”, which are incorporated by reference. The location identifier 38 allows the head-position circuit to coarsely determine and adjust the position of the head 14 with respect to the surface of the disk 12 ( FIG. 1 ). More specifically, the location identifier 38 includes a sector identifier 40 and a track identifier 42 , which respectively identify the disk sector 20 and the data track 22 —here the sector 20 a and the track 22 a —that contain the servo wedge 24 a . Because the head 14 may read the location identifier 38 even if the head is not centered over the track 24 a , the servo wedge 24 a also includes head-position bursts A-N, which allow the head-position circuit to finely determine and adjust the position of the head 14 .
FIG. 4 is a table of the Gray coded bit patterns 50 that form portions of the respective track identifiers 42 ( FIG. 3 ) for sixteen adjacent tracks 0-15 ( FIG. 2 ) and the corresponding uncoded bit patterns 52 . The uncoded patterns 52 for adjacent tracks differ by only one bit. For example, the only difference between the patterns 52 for the tracks 0 and 1 is that the least significant (rightmost) bit for track 0 is logic 0, and the least significant bit for track 1 is logic 1. Similarly, the Gray coded patterns 50 for adjacent tracks differ by only a pair of bits, or a one-bit shift in a pair of logic 1's. For example, the only difference between the patterns 50 for the tracks 0 and 1 is that the pair of least significant bits for track 0 are logic 0, and the pair of least significant bits for track 1 are logic 1. Moreover, the only difference between the patterns 50 for tracks 2 and 3 are that the pair of least significant logic 1's in the pattern 50 for track 2 are shifted left by one bit in the pattern 50 for track 3.
Still referring to FIG. 4 , the Gray coded patterns 50 allow the head-position circuit (not shown in FIG. 4 ) to determine the position of the read-write head 14 ( FIG. 1 ) within ±1 track. More specifically, the tracks 22 ( FIG. 1 ) are typically so close together that the head 14 often simultaneously picks up servo data from multiple tracks 22 , particularly if the head is between two tracks 22 . Consequently, the Gray coded patterns 50 are designed so that if the head 14 is between two tracks 22 , it generates a servo signal (not shown in FIG. 4 ) that ideally represents the Gray coded pattern 50 of the closest of these two tracks, but of no other track. For example, if the head 14 is between tracks 2 and 3 but closer to the center of track 2 than to the center of track 3, then the servo signal ideally represents the coded pattern 50 in track 2. If there is noise or another disturbance on the servo signal, however, then a servo circuit (not shown in FIG. 4 ) may read the servo signal as representing track 3, hence the ±1 track accuracy in the position of the head 14 . The head-position circuit uses this head-position information derived from the servo signal to position the head 14 over a desired track 22 . Once the head-position circuit positions the head 14 over a desired track 22 such that the servo signal represents the pattern 50 of the desired track, the head-position circuit uses bursts A-N ( FIG. 3 ) to center the head 14 over the desired track.
Referring again to FIG. 1 , during the manufacture of the disk drive 10 the head 14 may be reverse connected, in which case it reverses the phase of, i.e., inverts, the servo data as it reads a servo wedge 24 ( FIG. 2 ). Although not shown, the head 14 typically has two leads that are coupled to a servo circuit (not shown in FIGS. 1-4 ). The person or machine that assembles the disk-drive 10 may reverse the leads. If the leads are reversed, then the head 14 will invert the servo signal, and thus the servo data. Consequently, if left uncorrected, the inverted servo data may cause the disk drive 10 to malfunction. Although the manufacture can test the disk drive 10 and reconnect the head leads if they are reversed, such testing is often costly and time consuming.
As discussed above, techniques such as NRZ-NRZI-NRZ conversion are often used to compensate for a reverse-connected read-write head 14 . For example, the NRZ-NRZI-NRZ conversion converts data from one state to another such that the polarity of the resulting data recovered from the disk 12 ( FIG. 1 ) is the same whether the leads of the head 14 are properly or reverse connected. That is, NRZ-NRZI-NRZ conversion eliminates the need to test the head connection because the recovered data has the correct polarity regardless of the polarity of the connection.
Unfortunately, referring to FIG. 4 , NRZ-NRZI-NRZ conversion cannot be used with the Gray coded patterns 50 because it will destroy the characteristics of the patterns 50 that allow the head-position circuit (not shown in FIGS. 1-4 ) to determine the position of the read-write head 14 ( FIG. 1 ) with ±1 track accuracy.
SUMMARY
In one embodiment, a head-polarity detector includes a circuit for recovering servo data and a polarity determinator. The circuit recovers the servo data from a servo signal generated by a read-write head that is coupled to the circuit with a coupling polarity. The determinator determines the coupling polarity from the recovered servo data.
Such a detector allows a servo circuit to compensate for a reversed-coupled read-write head, and thus allows a manufacturer to forego time-consuming and costly testing of the head-connection polarity.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a conventional disk drive that includes a magnetic data-storage disk having disk sectors and data tracks.
FIG. 2 is a magnified view of the servo wedges on the disk of FIG. 1 .
FIG. 3 is a diagram of a servo wedge of FIG. 2 .
FIG. 4 is a table of conventional Gray coded track identifiers and the corresponding uncoded track identifiers for adjacent tracks on the disk of FIG. 1 .
FIG. 5 is a block diagram of a servo circuit that can determine the polarity of a read-write head connection and can compensate the servo signal if the connection is reversed according to an embodiment.
FIG. 6 is a block diagram of the synchronization-mark-and-polarity detector of FIG. 5 according to an embodiment.
FIG. 7A is a one-sample-at-a-time trellis diagram for a pruned, non-time-varying version of the Viterbi detector of FIG. 6 according to an embodiment.
FIG. 7B is a one-sample-at-a-time trellis diagram for a pruned, time-varying version of the Viterbi detector of FIG. 6 according to an embodiment.
FIG. 7C is a two-sample-at-a-time version of the trellis diagram of FIG. 7B .
FIG. 8 is a table of Gray coded track identifiers and the corresponding uncoded track identifiers for adjacent tracks on a disk according to an embodiment.
FIG. 9 is a block diagram of a disk-drive system that incorporates the servo circuit of FIG. 5 and that may incorporate the Gray coded track identifiers of FIG. 8 according to an embodiment.
DETAILED DESCRIPTION
FIG. 5 is block diagram of a synchronous servo circuit 60 , which in accordance with an embodiment includes a synchronization-mark-and-polarity detector 62 for recovering a synchronization mark such as the sync mark of Table I below, determining the connection polarity of a read-write head ( FIG. 9 ) from the recovered sync mark, and causing a phase-compensation circuit 64 to adjust the phase of the servo signal if the head connection is reversed. The detector 62 is further discussed below in conjunction with FIG. 6 , and in one embodiment, the circuit 64 includes a conventional twos-compliment inverter.
The circuit 60 also includes a gain and filter circuit 66 , which adjusts the gain of, filters, and equalizes the servo signal from the read-write head ( FIG. 9 ). An analog-to-digital converter (ADC) 68 receives a sample clock (not shown) on a control bus 70 and generates digital samples of the servo signal from the circuit 66 . A finite-impulse-response (FIR) filter 72 boosts the equalization of the samples received from the ADC 68 via the phase-compensation circuit 64 , and timing and gain recovery loops 74 effectively synchronize the sample clock to the servo signal and maintain the gain of the circuit 60 at a desired level. The phase-compensation circuit 64 , ADC 68 , FIR 72 , and loops 74 form a sample circuit 76 . A Viterbi detector 78 recovers servo data, such as the location identifier 38 ( FIG. 3 ), from the servo-signal samples generated by the loops 74 . A decoder 80 decodes the recovered servo data from the Viterbi detector 78 in response to a Sync Mark Detect signal from the detector 62 . A position-burst demodulator 82 receives samples of the servo signal from the FIR 72 and generates a head-position-error signal, and a processor 84 controls the components of the servo circuit 60 via the control bus 70 . For example, the processor 84 causes the circuit 64 to invert the samples from the ADC 68 in response to a predetermined logic level of a Head Polarity signal from the detector 62 . A servo-data interface 86 interfaces the decoder 80 , demodulator 82 , and processor 84 to a disk-drive controller ( FIG. 9 ). Alternatively, as discussed below, depending on the scheme used to code the servo data, the circuit 60 may omit the Viterbi detector 78 and use the detector 62 to recover all of the servo data. Furthermore, although shown located between the ADC 68 and the FIR 72 , the phase-compensation circuit 64 may be located elsewhere in the forward path of the servo circuit 60 such as at the input of the Viterbi detector 78 .
Still referring to FIG. 5 , the circuit 66 , ADC 68 , FIR 72 , loops 74 , Viterbi detector 78 , decoder 80 , processor 84 , and the general operation of the servo circuit 60 are further discussed in previously incorporated U.S. patent application Ser. Nos. 09/993,877 entitled “DATA-STORAGE DISK HAVING FEW OR NO SPIN-UP WEDGES AND METHOD FOR WRITING SERVO WEDGES ONTO THE DISK,” 09/993,876 entitled “CIRCUIT AND METHOD FOR DETECTING A SERVO WEDGE ON SPIN UP OF A DATA-STORAGE DISK”, 09/993,869 entitled “CIRCUIT AND METHOD FOR DETECTING A SPIN-UP WEDGE AND A CORRESPONDING SERVO WEDGE ON SPIN UP OF A DATA-STORAGE DISK”, 09/993,778 entitled “SERVO CIRCUIT HAVING A SYNCHRONOUS SERVO CHANNEL AND METHOD FOR SYNCHRONOUSLY RECOVERING SERVO DATA”. The timing-recovery loop of the loops 74 is further discussed in commonly owned U.S. patent application Ser. No. 09/387,146, filed Aug. 31, 1999, entitled “DIGITAL TIMING RECOVERY USING BAUD RATE SAMPLING”, which is incorporated by reference, and the gain-recovery loop of the loops 74 and the Viterbi detector 78 are also discussed in previously incorporated patent application Ser. No. 09/783,801, filed Feb. 14, 2001, entitled “VITERBI DETECTOR AND METHOD FOR RECOVERING A BINARY SEQUENCE FROM A READ SIGNAL”. The burst demodulator 82 is discussed in previously incorporated U.S. patent application Ser. No. 09/993,986 entitled “CIRCUIT AND METHOD FOR DEMODULATING A SERVO POSITION BURST”.
FIG. 6 is a block diagram of the synchronization-mark-and-polarity detector 62 of FIG. 5 according to an embodiment. The detector 62 includes a polarity-independent Viterbi detector 100 , which recovers the sync mark from the servo signal regardless of the head-connection polarity and which includes a bank 102 of path-history registers PH00-PHZ, one register for each state that the Viterbi detector 100 recognizes. A comparator 104 detects the sync mark and the head-connection polarity by comparing the recovered servo data from the Viterbi detector 100 with the noninverted version of the sync mark stored in a register 106 . The comparator 104 generates the Sync Mark Detect signal having one logic level when it detects the sync mark and another logic level otherwise, and generates the Head Polarity signal having one logic level when the head is properly coupled to the servo circuit 60 ( FIG. 5 ) and another logic level when the head connection is inverted. Alternatively, where the Viterbi detector 78 ( FIG. 5 ) is omitted, the servo circuit 60 ( FIG. 5 ) uses the Viterbi detector 100 to recover all of the servo data and to provide the recovered servo data to the decoder 80 .
Referring to FIGS. 5 and 6 , the operation of the servo circuit 60 and the sync-mark-and-polarity detector 62 according to an embodiment is discussed.
At the beginning of a read or write cycle, the servo circuit 60 synchronizes itself to the preamble of a servo wedge such as the preamble 34 of the servo wedge 24 a ( FIG. 3 ). Specifically, while the read-write head ( FIG. 9 ) is reading the preamble, the processor 84 causes the timing and gain recovery loops 74 to effectively synchronize the sample clock such that the ADC 68 samples the preamble at appropriate times. This synchronization is further discussed in commonly owned U.S. patent application Ser. No. 09/387,146, filed Aug. 31, 1999, entitled “DIGITAL TIMING RECOVERY USING BAUD RATE SAMPLING”, which is incorporated by reference.
When the circuit 60 is synchronized, the processor 84 enables the detector 62 to search for and detect the sync mark and the head-connection polarity. During this search, the comparator 104 compares the recovered servo data from the Viterbi detector 100 to the stored sync mark on a bit-by-bit basis. If and when the number of the recovered servo bits that match the corresponding bits of the stored sync mark is greater than or equal to a first predetermined threshold or less than or equal to a second predetermined threshold, then the comparator transitions the Sync Mark Detect signal to an active logic level to indicate that it has detected the sync mark. Furthermore, the comparator 104 transitions the Head Polarity signal to one logic level if the number of matched bits is greater than or equal to the first threshold, and transitions to the Head Polarity signal to another logic level if the number of matched bits is less than or equal to the second threshold. In one embodiment, the detector 62 allows the manufacturer to program the first and second predetermined thresholds to desired values. Furthermore, as discussed above in conjunction with FIG. 6 and below in conjunction with FIGS. 7A-7C , the Viterbi detector 100 is phase independent such that it can recover the sync mark from the servo data regardless of the connection polarity of the read-write head.
More specifically, the detector 62 detects the sync mark and determines the head-connection polarity according to the following algorithm:
If
∑
i
=
0
SM_length
-
1
SM
(
i
)
⊕
SM_recover
ed
(
i
)
≥
SM_length
-
Threshold
Then INV=1 (to indicate that this first comparison indicates recovery of the sync mark and that the head connection is inverted);
Else, INV=0 (to indicate that this first comparison does not indicate recovery of the sync mark and does not provide an indication of the head-connection polarity); and
If
∑
i
=
0
SM_length
-
1
SM
(
i
)
⊕
SM_recover
ed
(
i
)
≤
Threshold
NINV=1 (to indicate that this second comparison indicates recovery of the sync mark and that the head connection is not inverted);
Else, NINV=0 (to indicate that this second comparison does not indicate recovery of the sync mark and does not provide an indication of the head-connection polarity).
where SM_length equals the number of bits in the sync mark, SM equals the sync mark stored in the register 106 , SM_recovered equals the sync mark recovered from the Viterbi detector 100 , Threshold is the second predetermined threshold discussed above, and SM-length−Threshold is the first predetermined threshold discussed above.
For example, if the SM_length=10, SM=0000110011, SM_recovered equals 0100110011, and Threshold=2, then the summation of the algorithm equals the following:
0⊖0+0⊖1+0⊖0+0⊖0+1⊖1+1⊖1+0⊖0+0⊖0+1⊖1+1⊖1=1 (1)
Because 1<(Threshold=2)<(SM-length−Threshold=8), the comparator 104 sets INV=0 and NINV=1, which indicates that the circuit 62 has detected the sync mark and has determined that the head-connection polarity is not inverted. Consequently, the comparator 104 sets the Sync Mark Detect signal to a logic level that indicates that the sync mark is detected, and sets the Head Polarity signal to a logic level that indicates that the head connection is proper. In response to these logic levels, the processor 84 causes the phase compensator 64 to pass through the samples from the ADC 68 without altering the phase of the samples.
But if, for example, SM_recovered=1011001100, and the values of SM, SM-length, and Threshold are the same as above, then the summation of the algorithm equals the following:
0⊖1+0⊖0+0⊖1+0⊖1+1⊖0+1⊖0+0⊖1+0⊖1+1⊖0+1⊖0=9 (2)
Because 9>(SM_length−Threshold=8)>(Threshold=2), the comparator 104 sets INV=1 and NINV=0, which indicates that the circuit 62 has detected the sync mark and has determined that the head-connection polarity is inverted. Consequently, the comparator 104 sets the Sync Mark Detect signal to the logic level that indicates that the sync mark is detected, and sets the Head Polarity signal to a logic level that indicates that the head connection is inverted. In response to these logic levels, the processor 84 causes the phase compensator 64 to invert the samples from the ADC 68 . Alternatively, the manufacturer may disable the processor 84 from causing the compensator 64 to invert the samples, and instead swap the head leads in response to these logic levels so that the head is properly coupled to the servo circuit 60 .
Alternatively, if SM_recovered=1001001101 and the values of SM, SM-length, and Threshold are the same as above, then the summation of the algorithm equals the following:
0⊖1+0⊖0+0⊖0+0⊖1+1⊖0+1⊖0+0⊖1+0⊖1+1⊖0+1⊖1=7 (3)
Because (Threshold=2)<7<(SM_length−Threshold=8), the comparator 104 sets INV=NINV=0, which indicates that the circuit 62 has not detected the sync mark and has not determined the head-connection polarity. Consequently, the comparator 104 sets the Sync Mark Detect to a logic level that indicates that the sync mark has not been detected. In response to this logic level, the processor 84 ignores the Head Polarity signal and does not alter the setting (invert/noninvert) of the phase compensator 64 or instruct a technician to swap the head leads.
Although in the above examples one predetermined threshold (SM_length−Threshold) equals the difference between the length of the sync mark and the other predetermined threshold (Threshold), the one threshold may have a value that is independent of the other threshold. In one embodiment, the two thresholds are set based on the levels of noise and interference expected in the servo signal.
Still referring to FIGS. 5 and 6 , because in one embodiment the Viterbi detector 78 recovers servo data following the sync mark—the location identifier 38 ( FIG. 3 ) for example—before the detector 62 can determine the head-connection polarity, the decoder 80 discards the recovered servo data if the detector 62 determines that the head-connection polarity is reversed. This is because the detector 78 cannot properly recover inverted servo data. The processor 84 notifies the disk-drive controller ( FIG. 9 ) that the decoder 80 has discarded servo data, and the controller instructs the servo circuit 60 to restart the read or write cycle with the phase compensator 64 inverting the samples of the servo signal. Because restarting a read or write cycle is inefficient, the manufacturer typically programs the disk-drive controller to cause the servo circuit 60 to determine the head-connection polarity and set the phase-compensation circuit 64 during startup of the disk drive ( FIG. 9 ), and to thereafter disable the circuit 60 from determining the head-connection polarity. For example, the disk-drive controller may cause the processor 84 to store the value of the Head Polarity signal during startup, set the phase-compensation circuit 64 appropriately based on this stored polarity value, and thereafter maintain the setting of the circuit 64 and ignore the Head Polarity signal.
Conversely, in an embodiment where the servo data is coded such that the Viterbi detector 100 can recover both the sync mark and the other servo data, the polarity-detection capability of the comparator 104 can be omitted because the detector 100 is polarity independent. The servo circuit 60 , however, may include a data inverter (not shown) between the detector 62 and the decoder 80 , or at the output of the decoder 80 , so that the recovered servo data will be in a proper form for the disk-drive controller ( FIG. 9 ) if the head connection is inverted. An example of such a servo-data code is discussed below in conjunction with FIG. 8 .
FIG. 7A is a one-state-at-a-time trellis diagram for the Viterbi detector 100 of FIG. 5 according to an embodiment where the sync mark includes pairs and only pairs of consecutive logic 1's that are separated by no fewer than two consecutive logic 0's. In one embodiment, the Viterbi detector 100 is a pruned, non-time-varying PR4 detector where the values to the left of the slashes are the ideal PR4 sample values, the values to the right of the slashes are the possible values of the most recent bit sampled, and k, k+1, and k+2 are the relative sample times. In one application, the sync mark has the bit pattern given in Table I.
TABLE I
Sync Mark Bit Pattern
000000001100000011000011
The bit scheme of the sync mark allows the Viterbi detector 100 to have a reduced number of possible state transitions, i.e., to be “pruned.” Normally, each state S0-S3 of the trellis diagram would have two entering branches for a total of eight branches between the states at consecutive sample times. But with the restriction on the sync-mark bit pattern described above, there can be no state transition from S1 to S2 or from S2 to S1. Therefore, eliminating these two state transitions leaves only six branches between the states at consecutive sample times.
Furthermore, because the trellis of the Viterbi detector 100 is symmetrical about an imaginary horizontal axis 120 between states S1 and S2, the Viterbi detector 100 can recover the sync mark regardless of its polarity, and thus regardless of the head-connection polarity.
The fundamentals of Viterbi detectors and trellis diagrams are further discussed in commonly owned U.S. patent application Ser. No. 09/409,923, filed Sep. 30, 1999, entitled “PARITY-SENSITIVE VITERBI DETECTOR AND METHOD FOR RECOVERING INFORMATION FROM A READ SIGNAL”, and 09/410,274, filed Sep. 30, 1999, entitled “CIRCUIT AND METHOD FOR RECOVERING SYNCHRONIZATION INFORMATION FROM A SIGNAL”, which are incorporated by reference.
FIG. 7B is a one-state-at-a-time trellis diagram for the Viterbi detector 100 of FIG. 5 according to another embodiment where the sync mark includes pairs and only pairs of consecutive logic 1's that are separated by no fewer than two consecutive logic 0's. In one embodiment, the Viterbi detector 100 is a time-varying PR4 detector, and the sync mark has the bit pattern given in Table I above.
In addition to this embodiment of the Viterbi detector 100 being pruned like the FIG. 7A Viterbi detector, the sample clock is synchronized to the sync mark such that the detector 100 is time varying. More specifically, referring to Table I, the logic 0's and 1's of the sync mark always come in pairs. Therefore, at every other sample time, the only possible states of the sync mark are S0 or S3. Consequently, by identifying the first sample of the sync mark and configuring the detector 100 such that this first sample is aligned with the sample time k+1 of the trellis, the detector “knows” that at k and k+2 only states S0 and S3 are possible. Therefore, one can eliminate all branches entering states S1 and S2 at sample times k and k+2. But because the trellis between k and k+1 differs from the trellis between k+1 and k+2, the detector 100 is said to be time varying because the trellis depends on the sample time. Even so, because there are only four branches between the states at each consecutive sample time, the time-varying Viterbi detector is often less complex and more robust than the non-time-varying Viterbi detector discussed above in conjunction with FIG. 7A .
Furthermore, like the FIG. 7A Viterbi detector, this embodiment of the Viterbi detector 100 can recover the sync mark regardless of its polarity, and thus regardless of the head-connection polarity. Specifically, the trellis is symmetrical about the imaginary horizontal axis 120 between states S1 and S2. One may notice that because the sync mark of Table I has pairs and only pairs of logic 1's, the branches 122 and 124 can also be eliminated because the sync mark cannot have the state S3 at sample time k+1. But removing the branches 122 and 124 would destroy the symmetry about the imaginary axis 120 , and would thus render the Viterbi detector 100 polarity dependent. That is, if the head-connection polarity were inverted, the detector 100 would be unable to recover the sync mark. Consequently, the servo circuit 60 would be unable to compensate for the inverted head-connection polarity.
FIG. 7C is a two-sample-at-a-time version of the one-sample-at-a-time trellis diagram of FIG. 7B . Specifically, in this embodiment the sample circuit 76 , the Viterbi detector 78 , and the Viterbi detector 100 process two samples of the servo signal at a time. Therefore, the trellis of FIG. 7C is merely the trellis of FIG. 7B modified to reflect that the Viterbi detector 100 processes two samples at a time. Furthermore, the Viterbi detector 100 is non-time-varying when it processes two samples at a time.
In one embodiment, the two-sample-at-a-time Viterbi detector 100 calculates a difference metric instead of path metrics, and updates the contents of the path history registers 102 based on the difference metric. Consequently, the Viterbi detector 100 can include circuitry that is less complex than would be needed if it calculated path metrics.
The calculation of the difference metric is derived from the following PR4 path-metric equations, which use the following variables: PM00 equals the path metric for the state S0, PM11 equals the path metric for the state S1, Yf equals the first sample of a pair of samples (corresponds to k, k+2, k+4), Ys equals the second sample of a pair of samples (corresponds to k+1 and k+3, which are not shown in FIG. 7C ), DM equals the difference metric=½(PM00−PM11), and Yk=Yf+Ys. As discussed above, each sample of a pair of samples has the same value. That is each pair of samples is either 00 or 11. Thus, the complexity of the Viterbi detector 100 is equivalent to the complexity of a single interleaved PR4 detector.
If PM00 k <PM11 k +( Yf+ 1) 2 +( Ys+ 1) 2
Then PM00 k+1 =PM00 k
Else PM00 k+1 =PM11 k +( Yf+ 1) 2 +( Ys+ 1) 2 (4)
If PM11 k <PM00 k +( Yf− 1) 2 +( Ys− 1) 2
Then PM11 k+1 =PM11 k
Else PM11 k+1 =PM00 k +( Yf− 1) 2 +( Ys− 1) 2 (5)
Simplifying equations (4) and (5) to eliminate the square terms results in the following corresponding equations:
If PM00 k <PM11 k +2 Yf+ 2 Ys+ 2
Then PM00 k+1 =PM00 k
Else PM00 k+1 =PM11 k +2 Yf+ 2 Ys+ 2 (6)
If PM11 k <PM00 k −2 Yf− 2 Ys+ 2
Then PM11 k+1 =PM11 k
Else PM11 k+1 =PM00 k −2 Yf− 2 Ys+ 2 (7)
Simplifying equations (6) and (7) by incorporating DM and Yk in the inequalities results in the corresponding equations:
Yk >DM k −1 (8)
Yk <DM k +1 (9)
If equation (8) is false and equation (9) is true, then the Viterbi detector 100 updates DM and the path history registers PH00 and PH11 as follows, where 0 is the first (most recent) bit position and n is the last (least recent) bit position of the path registers:
DM k+1 =Yk+ 1 (10)
PH00(0: n ) k+1 =[0,0,PH11(0: n− 2) k ] (11)
PH11(0: n ) k+1 =[1,1,PH11(0: n− 2) k ] (12)
That is, the Viterbi detector 100 loads logic 0's into the two most recent bit positions 0 and 1 of PH00 and loads the remaining bit positions 2−n with the contents of the corresponding bit positions 0−n−2 of PH11. Next, the Viterbi detector 100 loads logic 1's into the two most recent bit positions 0 and 1 of PH11 while or after PH11 shifts the contents of its bit positions 0−n−2 into its bit positions 2−n.
If equation (8) is true and equation (9) is false, then the Viterbi detector 100 updates DM and the path history registers PH00 and PH11 as follows:
DM k+1 =Yk− 1 (13)
PH00(0: n ) k+1 =[0,0,PH00(0: n− 2) k ] (14)
PH11(0: n ) k+1 =[1,1,PH00(0: n− 2) k ] (15)
That is, the Viterbi detector 100 loads logic 1's into the two most recent bit positions 0 and 1 of PH11 and loads the remaining bit positions 2−n with the contents of the corresponding bit positions 0−n−2 of PH00. Next, the Viterbi detector 100 loads logic 0's into the two most recent bit positions 0 and 1 of PH00 while or after PH00 shifts the contents of its bit positions 0−n−2 into its bit positions 2−n.
If both equations (8) and (9) are true, then the Viterbi detector 100 updates DM and the path history registers PH00 and PH11 as follows:
DM k+1 =DM k (16)
PH00(0: n ) k+1 =[0,0,PH00(0: n− 2) k ] (17)
PH11(0: n ) k+1 =[1,1,PH11(0: n− 2) k ] (18)
That is, when both equations (8) and (9) are true, the Viterbi detector 100 loads logic 0's into the two most recent bit positions 0 and 1 of PH00 while or after PH00 shifts the contents of its bit positions 0−n−2 into its bit positions 2−n. Similarly, the Viterbi detector 100 loads logic 1's into the two most recent bit positions 0 and 1 of PH11 while or after PH11 shifts the contents of its bit positions 0−n−2 into its bit positions 2−n.
Equations (8) and (9) cannot both be false.
FIG. 8 is a table of Gray coded bit patterns 130 that form portions of the respective track identifiers 42 ( FIG. 3 ) for eight adjacent tracks 0-7 ( FIG. 2 ), and the corresponding uncoded bit patterns 132 according to an embodiment. The Gray coded bit patterns 130 include pairs and only pairs of consecutive logic 1's that are separated by no fewer than two consecutive logic 0's; therefore, the bit patterns 130 are compatible with the embodiments of the Viterbi detector 100 discussed above in conjunction with FIGS. 5-7C . Because the bit patterns 130 are compatible with the Viterbi detector 100 , they allow the manufacturer to simplify the servo circuit 60 ( FIG. 5 ) by eliminating the Viterbi detector 78 and using the Viterbi detector 100 to recover all of the servo data as discussed above in conjunction with FIGS. 5 and 6 . The coding scheme used to generate the Gray coded bit patterns 132 is discussed in commonly owned U.S. patent application Ser. No. 09/994,009 entitled “A DATA CODE AND METHOD FOR CODING DATA”, which is incorporated by reference.
FIG. 9 is a block diagram of a disk-drive system 200 that incorporates the servo circuit 60 of FIG. 5 according to an embodiment. The disk-drive system 200 includes a disk drive 202 , which includes a read-write head 204 , a write channel 206 for generating and driving the head 204 with a write signal, and a write controller 208 for interfacing the write data to the write channel 206 . The head 204 may be similar to the head 14 of FIG. 1 . The disk drive 202 also includes a read channel 210 , which incorporates the servo circuit 60 ( FIG. 5 ) for receiving a servo signal from the head 204 and for recovering servo data therefrom, and for providing the recovered servo data to a head-position circuit 212 . The read channel 210 also receives an application-data read signal and recovers application data therefrom. The disk drive 202 also includes a read controller 213 for organizing the read data. Together, the write and read controllers 208 and 213 compose a disk-drive controller 214 . The disk drive 202 further includes a storage medium such as one or more disks 215 , each of which may contain data on one or both sides and which may be a magnetic, optical, or another type of storage disk. For example, the disks 215 may be similar to the disk 12 of FIG. 1 . The head 204 writes/reads the data stored on the disks 215 , and is coupled to a movable support arm 216 , which may be similar to the support arm 16 of FIG. 1 . The head-position circuit 212 provides a control signal to a voice-coil motor (VCM) 218 , which positionally maintains/radially moves the arm 216 so as to positionally maintain/radially move the head 204 over the desired data tracks on the disks 215 . The VCM 218 may be similar to the VCM 18 of FIG. 1 . A spindle motor (SPM) 220 and a SPM control circuit 222 respectively rotates the disks 215 and maintains them at the proper rotational speed.
The disk-drive system 200 also includes write and read interface adapters 224 and 226 for respectively interfacing the disk-drive controller 214 to a system bus 228 , which is specific to the system used. Typical system busses include ISA, PCI, S-Bus, Nu-Bus, etc. The system 200 typically has other devices, such as a random access memory (RAM) 230 and a central processing unit (CPU) 232 coupled to the bus 228 .
From the foregoing it will be appreciated that, although specific embodiments have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the present disclosure. | A detector recovers servo data from a servo signal generated by a read-write head, and determines the head-connection polarity from the recovered servo data. Such a detector allows a servo circuit to compensate for a reversed-connected read-write head, and thus allows a manufacturer to forego time-consuming and costly testing to determine whether the head is correctly connected to the servo circuit. | 6 |
TECHNICAL FIELD
[0001] The present invention relates to a coding apparatus, a decoding apparatus, and methods thereof, which are used in a communication system that encodes and transmits a signal.
BACKGROUND ART
[0002] When a speech/audio signal is transmitted in a packet communication system typified by Internet communication, a mobile communication system, or the like, compression/coding technology is often used in order to increase speech/audio signal transmission efficiency. Furthermore, there is a growing demand for a technology of not simply encoding a speech/audio signal at a low bit rate but also encoding a wider band speech/audio signal in recent years.
[0003] In response to such a demand, various band extension technologies are being developed which encode a wideband speech/audio signal without drastically increasing the amount of coded information. For example, a technology is disclosed which applies gain information in a linear region and gain information in a logarithmic domain to spectrum data in a low-frequency part out of spectrum data obtained, for example, by converting an input audio signal corresponding to a certain time to generate spectrum data in a high-frequency part (see Patent Literature 1 and Non-Patent Literature 1). Furthermore, hierarchy coding schemes which encode a wideband signal in a hierarchical manner have been developed so far. For example, Non-Patent Literature 2 discloses a technology of encoding a wideband signal using a hierarchy coding scheme made up of five layers.
CITATION LIST
Patent Literature
[0000]
PTL 1
WO2007/052088
Non-Patent Literature
[0000]
NPTL 1
Mikko Tammi, Lasse Laaksonen, Anssi Ramo, and Henri Toukomaa, “Scalable Superwideband Extension for Wideband Coding”, ICASSP 2009
NPTL 2
ITU-T:G.718; Frame error robust narrowband and wideband embedded variable bit-rate coding of speech and audio from 8-32 kbit/s. ITU-T Recommendation G.718 (2008)
SUMMARY OF INVENTION
Technical Problem
[0010] However, when the band extension technologies disclosed in Patent Literature 1 and Non-Patent Literature 1 are applied to a hierarchy coding/decoding scheme (scalable codec) such as the one disclosed in Non-Patent Literature 2, there is a problem that coding efficiency is not sufficient. For example, consider a case where a difference spectrum between a high-frequency spectrum generated by the above-described band extension technology and an input spectrum is encoded in a higher layer. In this case, the high-frequency spectrum generated through the above-described band extension technology is not close to the input spectrum in signal level. Therefore (that is, an S/N (Signal/Noise) ratio of the generated high-frequency spectrum is low), energy of the difference spectrum which is a coding target in the higher layer increases. Therefore, particularly when the bit rate of the higher layer is low, coding performance becomes insufficient and quality of the decoded signal may deteriorate significantly.
[0011] It is an object of the present invention to provide a coding apparatus, a decoding apparatus, and methods thereof, when a band extension technology of encoding spectrum data in a high-frequency part based on spectrum data in a low-frequency part according to a hierarchy coding/decoding scheme is applied to a lower layer, which can perform efficient encoding also in a higher layer and improve the quality of a decoded signal.
Solution to Problem
[0012] A coding apparatus of the present invention adopts a configuration including: a first coding section that inputs a low-frequency decoded signal of a frequency domain generated using low-frequency coded information obtained by encoding an input signal and the input signal of the frequency domain, generates a high-frequency decoded signal of the frequency domain using high-frequency coded information obtained through encoding using the low-frequency decoded signal and the input signal, generates a band extension signal using the low-frequency decoded signal and the high-frequency decoded signal and generates a difference signal between the input signal and the band extension signal; and a second coding section that encodes the difference signal to generate difference coded information, wherein: the first coding section searches a part approximate to the high-frequency part of the input signal from the low-frequency decoded signal in encoding using the low-frequency decoded signal and the input signal to thereby obtain an ideal gain that minimizes energy of the difference signal, generate the difference signal that minimizes the energy and generate the high-frequency coded information including the ideal gain.
[0013] A decoding apparatus of the present invention adopts a configuration including: a receiving section that receives coded information, which is generated by a coding apparatus, including low-frequency coded information obtained by encoding an input signal, high-frequency coded information obtained through encoding using a low-frequency signal generated using the low-frequency coded information and the input signal and difference coded information generated through encoding using a difference signal between a band extension signal and the input signal, the band extension signal generated using a high-frequency signal generated using the high-frequency coded information and the low-frequency signal, the coded information, the high-frequency coded information of which includes an ideal gain that minimizes energy of the difference signal; a first decoding section that decodes the low-frequency coded information to generate a low-frequency decoded signal; a second decoding section that performs decoding using the low-frequency decoded signal and the high-frequency coded information to thereby generate a high-frequency decoded signal; and a third decoding section that decodes the difference coded information, wherein: the receiving section generates control information indicating whether or not the coded information includes the difference coded information, and the second decoding section performs decoding by switching between a first decoding method using all information included in the high-frequency coded information and a second decoding method using information included in the high-frequency coded information except specific information, based on the control information.
[0014] A coding method of the present invention includes: a first encoding step of inputting a low-frequency decoded signal of a frequency domain generated using low-frequency coded information obtained by encoding an input signal and the input signal of the frequency domain, generating a high-frequency decoded signal of the frequency domain using high-frequency coded information obtained through encoding using the low-frequency decoded signal and the input signal, generating a band extension signal using the low-frequency decoded signal and the high-frequency decoded signal and generating a difference signal between the input signal and the band extension signal; and a second encoding step of encoding the difference signal to generate difference coded information, wherein: in the first encoding step, a part approximate to a high-frequency part of the input signal is searched from the low-frequency decoded signal in encoding using the low-frequency decoded signal and the input signal to thereby obtain an ideal gain that minimizes energy of the difference signal, generate the difference signal that minimizes the energy and generate the high-frequency coded information including the ideal gain.
[0015] A decoding method of the present invention includes: a receiving step of receiving coded information, that is generated by a coding apparatus, including low-frequency coded information obtained by encoding an input signal, high-frequency coded information obtained through encoding using a low-frequency signal generated using the low-frequency coded information and the input signal, and difference coded information generated through encoding using a difference signal between a band extension signal and the input signal, the band extension signal generated using a high-frequency signal generated using the high-frequency coded information and the low-frequency signal, the coded information, the high-frequency coded information of which includes an ideal gain that minimizes energy of the difference signal; a first decoding step of decoding the low-frequency coded information to generate a low-frequency decoded signal; a second decoding step of performing decoding using the low-frequency decoded signal and the high-frequency coded information to thereby generate a high-frequency decoded signal; and a third decoding step of decoding the difference coded information, wherein: in the receiving step, control information indicating whether or not the coded information includes the difference coded information is generated, and in the second decoding step, decoding is performed by switching between a first decoding method using all information included in the high-frequency coded information and a second decoding method using information included in the high-frequency coded information except specific information, based on the control information.
Advantageous Effects of Invention
[0016] According to the present invention, in a hierarchy coding/decoding scheme, when a band extension technology of encoding spectrum data in a high-frequency part is applied to a lower layer based on spectrum data in a low-frequency part, it is possible to efficiently perform encoding also in a higher layer and thereby improve the quality of the decoded signal.
BRIEF DESCRIPTION OF DRAWINGS
[0017] FIG. 1 is a block diagram illustrating a configuration of a communication system including a coding apparatus and a decoding apparatus according to an embodiment of the present invention;
[0018] FIG. 2 is a block diagram illustrating a main internal configuration of the coding apparatus shown in FIG. 1 ;
[0019] FIG. 3 is a block diagram illustrating a main internal configuration of the third layer coding section shown in FIG. 2 ;
[0020] FIG. 4 is a block diagram illustrating a main internal configuration of the decoding apparatus shown in FIG. 1 ; and
[0021] FIG. 5 is a block diagram illustrating a main internal configuration of the third layer decoding section shown in FIG. 4 .
DESCRIPTION OF EMBODIMENTS
[0022] Referring to the drawings, one embodiment of the present invention will be described in detail. A speech coding apparatus and a sound decoding apparatus are described as examples of the coding apparatus and decoding apparatus of the invention.
Embodiment
[0023] FIG. 1 is a block diagram illustrating a configuration of a communication system including a coding apparatus and a decoding apparatus according to Embodiment of the invention. In FIG. 1 , the communication system includes coding apparatus 101 and decoding apparatus 103 , and coding apparatus 101 and decoding apparatus 103 can conduct communication with each other through transmission line 102 . Herein, the coding apparatus and decoding apparatus are usually mounted in a base station apparatus, a communication terminal apparatus, and the like for use.
[0024] Coding apparatus 101 divides an input signal into respective N samples (N is a natural number), and performs coding in each frame with the N samples as one frame. At this point, it is assumed that an input signal that becomes a coding target is expressed as x n (n=0, . . . , N−1). n denotes an (n+1)th signal element in the input signal that is divided every N sample. Coding apparatus 101 transmits encoded input information (hereinafter referred to as “coded information”) to decoding apparatus 103 through transmission line 102 .
[0025] Decoding apparatus 103 receives the coded information that is transmitted from coding apparatus 101 through transmission line 102 , and decodes the coded information to obtain an output signal.
[0026] FIG. 2 is a block diagram illustrating a main configuration of coding apparatus 101 in FIG. 1 . Coding apparatus 101 is mainly constructed of down-sampling processing section 201 , first layer coding section 202 , first layer decoding section 203 , up-sampling processing section 204 , orthogonal transform processing section 205 , second layer coding section 206 , second layer decoding section 207 , adder 208 , adder 209 , third layer coding section 210 , and coded information integration section 211 . Each section operates as follows.
[0027] When the sampling frequency of input signal x n is assumed to be SR input , down-sampling processing section 201 down-samples the sampling frequency of input signal x n from SR input to SR base (SR base <SR input ). Down-sampling processing section 201 outputs the down-sampled input signal to first layer coding section 202 as the down-sampled input signal.
[0028] First layer coding section 202 performs encoding on the down-sampled input signal inputted from down-sampling processing section 201 using, for example, a CELP (Code Excited Linear Prediction) speech coding method to generate first layer coded information. First layer coding section 202 outputs the generated first layer coded information to first layer decoding section 203 and coded information integration section 211 .
[0029] First layer decoding section 203 decodes the first layer coded information inputted from first layer coding section 202 using, for example, a CELP-based speech decoding method to generate a first layer decoded signal. First layer decoding section 203 then outputs the generated first layer decoded signal to up-sampling processing section 204 .
[0030] Up-sampling processing section 204 up-samples a sampling frequency of the first layer decoded signal inputted from first layer decoding section 203 from SR base to SR input . Up-sampling processing section 204 outputs the up-sampled first layer decoded signal to orthogonal transform processing section 205 as up-sampled first layer decoded signal x 1 n .
[0031] Orthogonal transform processing section 205 includes buffers buf 1 n and buf 2 n (n=0, . . . , N−1). Orthogonal transform processing section 205 applies modified discrete cosine transform (MDCT) to input signal x n and up-sampled first layer decoded signal x 1 n inputted from up-sampling processing section 204 .
[0032] An orthogonal transform processing in orthogonal transform processing section 205 , namely, an orthogonal transform processing calculating procedure and data output to an internal buffer will be described below.
[0033] First, orthogonal transform processing section 205 initializes buffers buf 1 n and buf 2 n according to equation 1 and equation 2 below assuming “0” as an initial value.
[0000] (Equation 1)
[0000] buf1 n =0( n= 0, . . . , N− 1) [1]
[0000] (Equation 2)
[0000] buf2 n =0( n= 0, . . . , N− 1) [2]
[0034] Next, orthogonal transform processing section 205 applies modified discrete cosine transform (MDCT) to input signal x n and up-sampled first layer decoded signal x 1 n according to equation 3 and equation 4 below. Orthogonal transform processing section 205 thereby calculates MDCT coefficient (hereinafter referred to as “input spectrum”) X(k) of the input signal and MDCT coefficient (hereinafter referred to as “first layer decoded spectrum”) X 1 (k) of up-sampled first layer decoded signal x 1 n .
[0000]
(
Equation
3
)
X
(
k
)
=
2
N
∑
n
=
0
2
N
-
1
x
n
′
cos
[
(
2
n
+
1
+
N
)
(
2
k
+
1
)
π
4
N
]
(
k
=
0
,
…
,
N
-
1
)
[
3
]
(
Equation
4
)
X
1
(
k
)
=
2
N
∑
n
=
0
2
N
-
1
x
1
n
′
cos
[
(
2
n
+
1
+
N
)
(
2
k
+
1
)
π
4
N
]
(
k
=
0
,
…
,
N
-
1
)
[
4
]
[0035] Where k is an index of each sample in one frame. Using following equation 5, orthogonal transform processing section 205 obtains x n ′ that is a vector formed by coupling input signal x n and buffer buf 1 n . Furthermore, using equation 6 below, orthogonal transform processing section 205 obtains x 1 n ′ that is a vector formed by coupling up-sampled first layer decoded signal x 1 n and buffer buf 2 n .
[0000]
(
Equation
5
)
x
n
′
=
{
buf
1
n
(
n
=
0
,
…
N
-
1
)
x
n
-
N
(
n
=
N
,
…
2
N
-
1
)
[
5
]
(
Equation
6
)
x
1
n
′
=
{
buf
2
n
(
n
=
0
,
…
N
-
1
)
x
1
n
-
N
(
n
=
N
,
…
2
N
-
1
)
[
6
]
[0036] Next, orthogonal transform processing section 205 updates buffers buf 1 n and buf 2 n according to equation 7 and equation 8.
[0000] (Equation 7)
[0000] buf1 n =x n ( n= 0, . . . N− 1) [7]
[0000] (Equation 8)
[0000] buf2 n =x 1 n ( n= 0 , . . . N− 1) [8]
[0037] Orthogonal transform processing section 205 then outputs input spectrum X(k) to second layer coding section 206 and adder 209 . Furthermore, orthogonal transform processing section 205 outputs first layer decoded spectrum X 1 (k) to second layer coding section 206 , second layer decoding section 207 , and adder 208 .
[0038] Second layer coding section 206 generates second layer coded information using input spectrum X(k) and first layer decoded spectrum X 1 (k), both of which are inputted from orthogonal transform processing section 205 . Second layer coding section 206 outputs the generated second layer coded information to second layer decoding section 207 , third layer coding section 210 , and coded information integration section 211 . The details of second layer coding section 206 will be described later.
[0039] Second layer decoding section 207 decodes the second layer coded information inputted from second layer coding section 206 to generate a second layer decoded spectrum. Second layer decoding section 207 outputs the generated second layer decoded spectrum to adder 208 . The details of second layer decoding section 207 will be described later.
[0040] Adder 208 adds up the first layer decoded spectrum inputted from orthogonal transform processing section 205 and the second layer decoded spectrum inputted from second layer decoding section 207 in a frequency domain to calculate an addition spectrum. Here, the first layer decoded spectrum is a spectrum that has a value in a low-frequency part (0(kHz) to F base (kHz)) corresponding to sampling frequency SR base . Furthermore, the second layer decoded spectrum is a spectrum that has a value in a high-frequency part (F base (kHz) to F input (kHz)) corresponding to sampling frequency SR input . That is, the value in the low-frequency part (0(kHz) to F base (kHz)) of an addition spectrum obtained by adding up these spectra is a first layer decoded spectrum and the value in the high-frequency part (F base (kHz) to F input (kHz)) is a second layer decoded spectrum.
[0041] Adder 209 adds the addition spectrum inputted from adder 208 to input spectrum X(k) inputted from orthogonal transform processing section 205 while inverting the polarity of the addition spectrum, thereby calculating a second layer difference spectrum. Adder 209 outputs the calculated second layer difference spectrum to third layer coding section 210 .
[0042] Third layer coding section 210 encodes the second layer difference spectrum inputted from adder 209 and the second layer coded information inputted from second layer coding section 206 to generate third layer coded information. Third layer coding section 210 outputs the generated third layer coded information to coded information integration section 211 . The details of third layer coding section 210 will be described later.
[0043] Coded information integration section 211 integrates the first layer coded information inputted from first layer coding section 202 , the second layer coded information inputted from second layer coding section 206 , and the third layer coded information inputted from third layer coding section 210 . Coded information integration section 211 adds a transmission error code or the like to the integrated information source code as required and outputs the resulting code to transmission line 102 as coded information.
[0044] Next, the processing in second layer coding section 206 will be described. The processing in second layer coding section 206 is similar to the processing of “High frequency Coding” shown in FIG. 7 of Patent Literature 1. That is, second layer coding section 206 calculates parameters (spectrum index i, first gain parameter α 1 , second gain parameter α 2 in Patent Literature 1) from the first layer decoded spectrum (X̂ L (k) in FIG. 7 of Patent Literature 1) and the input spectrum (X H (k) in FIG. 7 of Patent Literature 1) to generate a high-frequency spectrum at the decoding apparatus side. As described above, the first layer decoded spectrum is a spectrum in the low-frequency part (0(kHz) to F base (kHz)) and the input spectrum is a spectrum in the high-frequency part (F base (kHz) to F input (kHz)). Suppose the above-described three parameters which will be used in the following description are parameters calculated using the method disclosed in Patent Literature 1.
[0045] Here, the method of calculating the above-described three parameters disclosed in Patent Literature 1 and Non-Patent Literature 1 will be described.
[0046] First, a part similar to the spectrum in the high-frequency part (F base (kHz) to F input (kHz)) of input spectrum X(k) is searched with respect to first layer decoded spectrum X 1 (k). To be more specific, a spectrum index where the value (S(d)) in equation 9 below is maximized is searched and this spectrum index is assumed to be i. Here, j in equation 9 is a sub-band index, d is a spectrum index during the search and n j is a search range (the number of search entries) with respect to sub-band j.
[0000]
(
Equation
9
)
S
(
d
)
=
∑
k
=
0
n
j
-
1
(
X
H
j
(
k
)
X
^
L
(
d
+
k
)
)
∑
k
=
0
n
j
-
1
X
^
L
(
d
+
k
)
2
[
9
]
[0047] Next, first gain parameter α 1 is calculated according to equation 10 using spectrum index i that maximizes equation 9.
[0000]
(
Equation
10
)
α
1
(
j
)
=
∑
k
=
0
n
j
-
1
(
X
H
j
(
k
)
X
^
L
j
(
d
+
k
)
)
∑
k
=
0
n
j
-
1
X
^
L
j
(
d
+
k
)
2
[
10
]
[0048] Next, second gain parameter α 2 is calculated according to equation 11 using spectrum index i and gain parameter α 1 calculated according to equation 9 and equation 10.
[0000]
(
Equation
11
)
α
2
(
j
)
=
∑
k
=
0
n
j
-
1
(
(
log
10
(
α
1
(
j
)
X
^
L
j
(
k
)
-
M
j
)
)
(
log
10
(
α
1
(
j
)
X
L
j
(
k
)
-
M
j
)
)
)
∑
k
=
0
n
j
-
1
(
log
10
(
α
1
(
j
)
X
^
L
j
(
k
)
-
M
j
)
)
2
[
11
]
[0049] Here, suppose Mj in equation 11 is a value that satisfies equation 12 below.
[0000]
(
Equation
12
)
M
j
=
max
k
(
log
10
(
α
1
(
j
)
X
^
L
j
(
k
)
)
)
[
12
]
[0050] That is, in the second coding layer, the most approximate part to the high-frequency part of the input spectrum is searched with respect to the first decoded spectrum first. In this search, spectrum index i indicating the approximate spectrum part as well as an ideal gain at that time is calculated as first gain parameter α 1 . Then, second gain parameter α 2 which is a gain parameter to adjust energy in the logarithmic domain is calculated with respect to the high-frequency spectrum calculated from spectrum index i and first gain parameter α 1 being an ideal gain at that time, and the high-frequency part of the input spectrum.
[0051] Next, the processing in second layer decoding section 207 will be described. The processing in second layer decoding section 207 is identical to part of the processing in “High frequency generation” shown in FIG. 7 of Patent Literature 1.
[0052] First, second layer decoding section 207 generates high-frequency spectrum X 1 ′ j H (k) in the high-frequency part (F base (kHz) to F input (kHz)) as shown in equation 13. That is, second layer decoding section 207 generates high-frequency spectrum X 1 ′ j H (k) from spectrum index i out of the parameters (spectrum index i, first gain parameter α 1 , second gain parameter α 2 ) included in the second layer coded information, and from first layer decoded spectrum X 1 (k). Here, suppose j in equation 13 is a sub-band index and spectrum index i is set for each sub-band. Furthermore, here, spectrum index i, first gain parameter α 1 , and second gain parameter α 2 are parameters calculated using the method (described above) disclosed in Patent Literature 1.
[0053] That is, equation 13 represents the processing of approximating the spectrum corresponding to the sub-band width of sub-band index j from the index indicated by spectrum index of the first decoded spectrum onward, as a spectrum of the high-frequency part.
[0000] (Equation 13)
[0000] X 1′ H j ( k )= X 1( k−i j )( j= 0 , . . . , L− 1) [13]
[0054] Next, second layer decoding section 207 multiplies high-frequency spectrum X 1 ′ j H (k) calculated according to equation 13 by first gain parameter α 1 as shown in equation 14 below to calculate second layer decoded spectrum X 2 j H (k).
[0000] (Equation 14)
[0000] X 2 H j ( k )=α 1 ( j )· X 1′ H j ( k )( j= 0, . . . , L− 1) [14]
[0055] Next, second layer decoding section 207 outputs second layer decoded spectrum X 2 j H (k) calculated according to equation 14 to adder 208 .
[0056] That is, second layer decoding section 207 of the present embodiment generates a high-frequency spectrum (second layer decoded spectrum) without using second gain parameter α 2 unlike “High frequency generation” shown in FIG. 7 of Patent Literature 1. This is intended to reduce the energy of the second layer difference spectrum which is a quantization target in the higher layer and this processing allows coding efficiency to be improved in the higher layer.
[0057] Next, the processing in third layer coding section 210 will be described. FIG. 3 is a block diagram illustrating an internal configuration of third layer coding section 210 . As shown in FIG. 3 , third layer coding section 210 is mainly constructed of shape coding section 301 , gain coding section 302 and multiplexing section 303 . Each section operates as follows.
[0058] Shape coding section 301 performs shape quantization on the second layer difference spectrum inputted from adder 209 for each sub-band. To be more specific, shape coding section 301 divides the second layer difference spectrum into L sub-bands first. Here, suppose the number of sub-bands L is the same as the number of sub-bands in second layer coding section 206 . Next, shape coding section 301 searches a built-in shape codebook made up of SQ shape code vectors with respect to each of the L sub-bands and obtains an index of a shape code vector in which evaluation scale Shape_q(i) in equation 15 below is maximized.
[0000]
(
Equation
15
)
Shape_q
(
i
)
=
{
∑
k
=
0
W
(
j
)
(
X
2
H
′
j
(
k
)
·
SC
k
i
)
}
2
∑
k
=
0
W
(
j
)
SC
k
i
·
SC
k
i
(
j
=
0
,
…
,
L
-
1
,
i
=
0
,
…
,
SQ
-
1
)
[
15
]
[0059] Where SC i k is the shape code vector constituting the shape code book, i is the index of the shape code vector, and k is the index of the element of the shape code vector. Furthermore, W(j) denotes the band width of a band whose band index is j. Furthermore, suppose X 2 ′ j H (k) denotes a value of the second layer difference spectrum whose band index is j.
[0060] Shape coding section 301 outputs index S_max of a shape code vector in which evaluation scale Shape_q(i) of equation 15 above is maximized to multiplexing section 303 as the shape coded information. Shape coding section 301 calculates ideal gain Gain_i(j) according to following equation (16), and outputs calculated ideal gain Gain_i(j) to gain coding section 302 .
[0000]
(
Equation
16
)
Gain_i
(
j
)
=
∑
k
=
0
W
(
j
)
(
X
2
H
′
j
(
k
)
·
SC
k
S
_
max
)
∑
k
=
0
W
(
j
)
SC
k
S
_
max
·
SC
k
S
_
max
(
j
=
0
,
…
,
L
-
1
)
[
16
]
[0061] Gain coding section 302 receives ideal gain Gain_i(j) from shape coding section 301 . Furthermore, gain coding section 302 receives the second layer coded information from second layer coding section 206 as input.
[0062] Gain coding section 302 quantizes ideal gain Gain_i(j) inputted from shape coding section 301 according to following equation (17). Here, gain coding section 302 also deals with the ideal gain as an L-dimensional vector and performs vector quantization. Furthermore, in equation 17, β(j) is a preset constant and hereinafter will be referred to as a “predictive gain.” Predictive gain β(j) will be described later.
[0000]
(
Equation
17
)
Gain_q
(
i
)
=
{
∑
j
=
0
L
-
1
{
Gain_i
(
j
)
-
β
(
j
)
-
GC
j
i
}
}
2
(
i
=
0
,
…
,
GQ
-
1
)
[
17
]
[0063] Where GC i j is the gain code vector constituting the gain code book, i is the index of the gain code vector, and j is the index of the element of the gain code vector.
[0064] Gain coding section 302 searches the built-in gain codebook made up of GQ gain code vectors, and outputs index G_min of the gain codebook that minimizes equation 17 above to multiplexing section 303 as the gain coded information.
[0065] Next, a method of setting predictive gain β(j) in equation 17 will be described. Predictive gain β(j) is a constant preset for each sub-band (j is a sub-band index), the constant preset corresponding to second gain parameter α 2 in second layer coding section 206 , and is stored together in the codebook used when second gain parameter α 2 is quantized. That is, predictive gain β(j) is set for each code vector when second gain parameter α 2 is quantized. This allows decoding apparatus 103 (also including local decoding processing in coding apparatus 101 ) to obtain predictive gain β(j) corresponding to second gain parameter α 2 without using any additional amount of information. The value of predictive gain β(j) is a numerical value determined after statistically analyzing what type of value ideal gain Gain_i(j) calculated in shape coding section 301 at that time is with respect to the value of second gain parameter α 2 .
[0066] To be more specific, when the value of second gain parameter α 2 is large (close to 1.0), the energy of the second difference spectrum tends to be relatively small. Therefore, in such a case, the value of predictive gain β(j) is small. Furthermore, when the value of second gain parameter α 2 is small (close to 0.0), the energy of the second difference spectrum tends to be relatively large. Therefore, in such a case, the value of predictive gain β(j) is large.
[0067] Using such a characteristic, gain coding section 302 receives very long sample data as input and statistically analyzes the value of ideal gain Gain_i(j) corresponding to the value of second gain parameter α 2 . Gain coding section 302 determines the value of predictive gain β(j) corresponding to each value of second gain parameter α 2 stored in the codebook of second gain parameter α 2 . The method of setting predictive gain β(j) using equation 17 has been described above.
[0068] Multiplexing section 303 multiplexes shape coded information S_max inputted from shape coding section 301 and gain coded information G_min inputted from gain coding section 302 , and outputs the multiplexed information to coded information integration section 211 as the third layer coded information.
[0069] The configuration of third layer coding section 210 has been described above.
[0070] The configuration of coding apparatus 101 has been described above.
[0071] Next, decoding apparatus 103 shown in FIG. 1 will be described.
[0072] FIG. 4 is a block diagram illustrating a main internal configuration of decoding apparatus 103 . Decoding apparatus 103 is mainly constructed of coded information demultiplexing section 401 , first layer decoding section 402 , up-sampling processing section 403 , orthogonal transform processing section 404 , second layer decoding section 405 , third layer decoding section 406 , adder 407 , and orthogonal transform processing section 408 . Each section operates as follows.
[0073] Coded information demultiplexing section 401 receives the coded information transmitted from coding apparatus 101 via transmission line 102 . Coded information demultiplexing section 401 demultiplexes the coded information into first layer coded information, second layer coded information, and third layer coded information. Next, coded information demultiplexing section 401 outputs the first layer coded information to first layer decoding section 402 , outputs the second layer coded information to second layer decoding section 405 , and outputs the third layer coded information to third layer decoding section 406 .
[0074] Furthermore, coded information demultiplexing section 401 detects whether or not the coded information includes the third layer coded information and controls the operation of second layer decoding section 405 according to the detection result. To be more specific, when the coded information includes the third layer coded information, coded information demultiplexing section 401 sets the value of second layer control information CI to 0 and sets the value of second layer control information CI to 1 otherwise. Next, coded information demultiplexing section 401 outputs second layer control information CI to second layer decoding section 405 .
[0075] First layer decoding section 402 performs decoding on the first layer coded information inputted from coded information demultiplexing section 401 using, for example, a CELP-based speech decoding method to generate a first layer decoded signal. First layer decoding section 402 outputs the generated first layer decoded signal to up-sampling processing section 403 .
[0076] Up-sampling processing section 403 up-samples the sampling frequency of the first layer decoded signal, inputted from first layer decoding section 402 , from SR base to SR input . Up-sampling processing section 403 outputs the up-sampled first layer decoded signal to orthogonal transform processing section 404 as the up-sampled first layer decoded signal.
[0077] Orthogonal transform processing section 404 incorporates buffer buf 3 n (n=0, . . . , N−1), and performs modified discrete cosine transform (MDCT) on up-sampled first layer decoded signal x 1 n inputted from up-sampling processing section 403 . Orthogonal transform processing section 404 performs orthogonal transform processing on up-sampled first layer decoded signal x 1 n to calculate first layer decoded spectrum X 1 (k). Since the processing in orthogonal transform processing section 404 is similar to the processing in orthogonal transform processing section 205 , descriptions thereof will be omitted. Orthogonal transform processing section 404 outputs first layer decoded spectrum X 1 (k) obtained to second layer decoding section 405 .
[0078] Second layer decoding section 405 receives the second layer coded information and second layer control information from coded information demultiplexing section 401 as input. Furthermore, second layer decoding section 405 also receives first layer decoded spectrum X 1 (k) from orthogonal transform processing section 404 as input. Second layer decoding section 405 switches between decoding methods according to the value of the second layer control information and calculates a second layer decoded spectrum from first layer decoded spectrum X 1 (k) and the second layer coded information. Next, second layer decoding section 405 calculates a first addition spectrum from the second layer decoded spectrum and the first layer decoded spectrum and outputs the first addition spectrum to adder 407 . The details of second layer coding section 405 will be described later.
[0079] Third layer decoding section 406 receives the third layer coded information from coded information demultiplexing section 401 . Third layer decoding section 406 decodes the third layer coded information to calculate a third layer decoded spectrum. Next, third layer decoding section 406 outputs the calculated third layer decoded spectrum to adder 407 . The details of third layer coding section 406 will be described later.
[0080] Adder 407 receives the first addition spectrum from second layer decoding section 405 as input. Furthermore, adder 407 receives the third layer decoded spectrum from third layer decoding section 406 as input. Adder 407 adds up the first addition spectrum and the third layer decoded spectrum on the frequency axis to calculate the second addition spectrum. Next, adder 407 outputs the calculated second addition spectrum to orthogonal transform processing section 408 .
[0081] Orthogonal transform processing section 408 applies orthogonal transform to the second addition spectrum inputted from adder 407 to convert the second addition spectrum to a time-domain signal. Orthogonal transform processing section 408 outputs the signal obtained as an output signal. The details of the processing of orthogonal transform processing section 408 will be described later.
[0082] Next, the processing of second layer decoding section 405 will be described. The processing of second layer decoding section 405 is partially identical to that of second layer decoding section 207 in coding apparatus 101 .
[0083] Second layer decoding section 405 generates high-frequency spectrum X 1 ′ j H (k) of the high-frequency part (F base (kHz) to F input (kHz)) as shown in equation 13 above. That is, second layer decoding section 405 generates high-frequency spectrum X 1 ′ j H (k) from spectrum index i and first layer decoded spectrum X 1 (k) among parameters (spectrum index i, first gain parameter α 1 , second gain parameter α 2 ) included in the second layer coded information. Here, in equation 13, suppose j is a sub-band index and spectrum index i is set for each sub-band. Furthermore, spectrum index i, first gain parameter α 1 , and second gain parameter α 2 here are parameters calculated using the (above-described) method disclosed in Patent Literature 1.
[0084] That is, equation 13 indicates processing of approximating a spectrum corresponding to a sub-band width of sub-band index i from an index indicated by spectrum index i j of first decoded spectrum onward, as a spectrum of the high-frequency part.
[0085] Next, second layer decoding section 405 multiplies high-frequency spectrum X 1 ′ j H (k) calculated according to equation 13 by first gain parameter α 1 as shown in equation 18 to calculate high-frequency spectrum X 1 ″ j H (k).
[0000] (Equation 18)
[0000] X 1″ H j ( k )=α i ( j )· X 1′ H j ( k ) [18]
[0086] Next, second layer decoding section 405 calculates second layer decoded spectrum X 2 j H (k) according to equation 19 below depending on the value of inputted second layer control information CI. Here, in equation 19, ζ(k) is a variable which is −1 when the value of high-frequency spectrum X 1 ″ j H (k) is negative and +1 otherwise. Furthermore, M j is a value that satisfies equation 20 below.
[0000]
(
Equation
19
)
X
2
H
j
(
k
)
=
{
X
1
H
″
j
(
k
)
(
if
CI
=
0
)
ζ
(
k
)
·
10
α
2
(
j
)
(
log
10
(
X
1
H
*
j
(
k
)
)
-
M
j
)
+
M
j
(
if
CI
=
1
)
(
j
=
0
,
…
,
L
-
1
)
[
19
]
(
Equation
20
)
M
j
=
max
k
(
log
10
(
X
1
H
″
j
(
k
)
)
)
(
j
=
0
,
…
,
L
-
1
)
[
20
]
[0087] When the value of second layer control information CI is 0, that is, when the coded information includes the third layer coded information, second layer decoding section 405 calculates the second layer decoded spectrum using a method similar to the method calculated by second layer decoding section 207 in coding apparatus 101 . Furthermore, when the value of second layer control information CI is 1, that is, when the coded information does not include the third layer coded information, second layer decoding section 405 calculates a second layer decoded spectrum using a method different from the method calculated by second layer decoding section 207 . To be more specific, when the value of second layer control information CI is 1, second layer decoding section 405 calculates a second layer decoded spectrum using a gain parameter (second gain parameter α 2 ) in the logarithmic domain as disclosed in Patent Literature 1 and Non-Patent Literature 1.
[0088] As described above, adder 407 adds up the first addition spectrum decoded in second layer decoding section 405 , and the third layer decoded spectrum decoded in third layer decoding section 406 which is a higher layer of second layer decoding section 405 . Therefore, when a third decoded spectrum, which is a higher layer, exists, second layer decoding section 405 adopts a decoding method corresponding to second layer decoding section 207 in coding apparatus 101 . Thus, adder 407 is designed so as to calculate the most accurate spectrum after the addition.
[0089] On the other hand, when the third decoded spectrum of the higher layer does not exist, the first addition spectrum is not added to the third layer decoded spectrum. For this reason, second layer decoding section 405 adopts a decoding method that makes the signal perceptually closer to the input signal although the signal level (SNR) is lowered.
[0090] Next, second layer decoding section 405 adds up second layer decoded spectrum X 2 j H (k) calculated according to equation 19 and first layer decoded spectrum X 1 (k) in the frequency domain to calculate a first addition spectrum. Here, first layer decoded spectrum X 1 (k) is a spectrum that has a value in the low-frequency part (0(kHz) to F base (kHz)) corresponding to sampling frequency SR base . Furthermore, second layer decoded spectrum X 2 j H (k) is a spectrum that has a value in the high-frequency part (F base (kHz) to F input (kHz)) corresponding to sampling frequency SR input . That is, the value of the low-frequency part (0(kHz) to F base (kHz)) of the first addition spectrum obtained by adding up these spectra is a first layer decoded spectrum. Furthermore, the value of the high-frequency part (F base (kHz) to F input (kHz)) is a second layer decoded spectrum. This addition processing is similar to the processing of adder 208 in coding apparatus 101 .
[0091] Next, second layer decoding section 405 outputs the calculated first addition spectrum to adder 407 .
[0092] FIG. 5 is a block diagram illustrating a main configuration of third layer decoding section 406 .
[0093] In FIG. 5 , third layer decoding section 406 includes demultiplexing section 501 , shape decoding section 502 , and gain decoding section 503 .
[0094] Demultiplexing section 501 demultiplexes the third layer coded information outputted from coded information demultiplexing section 401 into shape coded information and gain coded information, outputs the obtained shape coded information to shape decoding section 502 and outputs the obtained gain coded information to gain decoding section 503 .
[0095] Shape decoding section 502 decodes the shape coded information inputted from demultiplexing section 501 and outputs the value of the shape obtained to gain decoding section 503 . Shape decoding section 502 incorporates a shape codebook similar to the shape codebook provided in shape coding section 301 of third layer coding section 210 . Shape decoding section 502 searches a shape code vector in which shape coded information S_max inputted from demultiplexing section 501 is used as an index. Shape decoding section 502 outputs the searched shape code vector to gain decoding section 503 . Here, suppose the shape code vector searched as the shape value is expressed by Shape_q(k) (k=0, . . . , B(j)−1).
[0096] Gain decoding section 503 receives gain coded information from demultiplexing section 501 as input. Gain decoding section 503 incorporates a gain codebook similar to the gain codebook provided in gain coding section 302 in third layer coding section 210 , and dequantizes the gain value using this gain codebook according to equation 21 below. Here, gain decoding section 503 also deals with the gain value as an L-dimensional vector to perform vector dequantization. Here, predictive gain β(j) is a value referenced from the above-described gain codebook using the index indicated by the gain coded information.
[0000] (Equation 21)
[0000] Gain — q ′( j )= GC j G — min +β( j )( j= 0 , . . . , L− 1) [21]
[0097] The processing in equation 21 corresponds to the inverse processing in equation 17 used by third layer coding section 210 in coding apparatus 101 to search the gain code vector. That is, instead of using gain code vector GC j G — min corresponding to gain coded information G_min as the gain value as is, a value obtained by adding predictive gain β(j) to gain code vector GC j G — min is used as the gain value. Of course, the value of predictive gain β(j) referenced here has the same value as predictive gain β(j) referenced when the gain information is encoded.
[0098] Next, gain decoding section 503 calculates a decoded MDCT coefficient as third layer decoded spectrum X 3 (k) according to equation 22 below using the gain value obtained through dequantization of the current frame and the shape value inputted from shape decoding section 502 . Here, the calculated decoded MDCT coefficient is expressed by X 3 (k).
[0000]
(
Equation
22
)
X
3
(
k
)
=
Gain_q
′
(
j
)
·
Shape_q
′
(
k
)
(
k
=
0
,
…
,
B
(
j
)
-
1
j
=
0
,
…
,
L
-
1
)
[
22
]
[0099] Gain decoding section 503 outputs third layer decoded spectrum X 3 (k) calculated according to equation 22 above to adder 407 .
[0100] The processing of third layer decoding section 406 has been described above.
[0101] Hereinafter, more specific processing of orthogonal transform processing section 408 will be described below.
[0102] Orthogonal transform processing section 408 incorporates buffer buf 4 (k) and initializes buffer buf 4 (k) as shown in equation 23 below.
[0000] (Equation 23)
[0000] buf4( k )=0( k= 0 , . . . , N− 1) [23]
[0103] Furthermore, orthogonal transform processing section 408 calculates and outputs decoded signal y n according to equation 24 below using second addition spectrum X_add(k) inputted from adder 407 .
[0000]
(
Equation
24
)
y
n
=
2
N
∑
n
=
0
2
N
-
1
Z
2
(
k
)
cos
[
(
2
n
+
1
+
N
)
(
2
k
+
1
)
π
4
N
]
(
n
=
0
,
…
,
N
-
1
)
[
24
]
[0104] Z 2 (k) in equation 24 is a vector formed by coupling second addition spectrum X_add(k) and buffer buf 4 (k) as shown in equation 25 below.
[0000]
(
Equation
25
)
Z
2
(
k
)
=
{
buf
4
(
k
)
(
k
=
0
,
…
N
-
1
)
X_add
(
k
)
(
k
=
N
,
…
2
N
-
1
)
[
25
]
[0105] Next, orthogonal transform processing section 408 updates buffer buf 4 (k) according to equation 26 below.
[0000] (Equation 26)
[0000] buf4( k )= X _add( k )( k= 0 , . . . N− 1) [26]
[0106] Next, orthogonal transform processing section 408 outputs decoded signal y n as the output signal.
[0107] The internal configuration of decoding apparatus 103 has been described above.
[0108] Thus, according to the present embodiment, when the coding apparatus/decoding apparatus uses a hierarchy coding/decoding scheme and also applies to a lower layer, a band extension technology of encoding spectrum data in a high-frequency part based on spectrum data in a low-frequency part, it is also possible to efficiently encode a difference spectrum (difference signal) and improve the quality of a decoded signal even in a higher layer. To be more specific, second layer decoding section 207 that performs band extension processing calculates a spectrum (difference spectrum) which becomes the coding target in third layer coding section 210 of the higher layer not using the gain information (second gain parameter α 2 ) for adjusting the energy of the spectrum in the high-frequency part generated using the spectrum of the low-frequency part, but using such gain information (first gain parameter α 1 ) that minimizes the energy of the difference spectrum. This enables third layer coding section 210 in the higher layer to encode the difference spectrum having smaller energy, and can thereby improve coding efficiency.
[0109] Furthermore, third layer coding section 210 quantizes an error component obtained by subtracting from gain information, a gain value (corresponding to predictive gain β(j)) statistically calculated from gain information (corresponding to above-described second gain parameter α 2 ) calculated at the time of band extension processing, as the gain information of the difference spectrum. This makes it possible to further improve coding efficiency.
[0110] The present embodiment has described the configuration of switching between methods of calculating a difference spectrum (second layer difference spectrum) in a lower layer in frame units, as shown in equation 19. However, the present invention is not limited to this, but is likewise applicable to a configuration of switching between methods of calculating a difference spectrum in sub-band units in a frame. For example, the present invention is also applicable to a case as disclosed in Non-Patent Literature 2 where a higher layer selects a band which is a quantization target in every frame (BS-SGC (Band Selective Shape Gain Coding) in Non-Patent Literature 2 corresponds to this). In this case, for a sub-band selected by the higher layer as the quantization target, the lower layer performs processing in the case of CI=0 in equation 19 to calculate a difference spectrum. Furthermore, for a sub-band not selected as the quantization target, the lower layer performs processing in the case of CI=1 in equation 15 to calculate a difference spectrum. By this means, it is possible to improve the coding efficiency of the higher layer by switching between methods of calculating a difference spectrum for each sub-band.
[0111] The present embodiment has described, by way of example, the configuration in which the error component is quantized as gain information of the difference spectrum in a higher layer rather than the layer that performs band extension processing. Here, the “error component” is a component obtained by subtracting the gain value (predictive gain β(j) corresponds to this) statistically calculated from gain information (above-described second gain parameter α 2 corresponds to this) calculated at the time of band extension processing. However, the present invention is not limited to this, but the present invention is likewise applicable to, for example, a configuration in which the higher layer quantizes gain information without using predictive gain β(j). In this case, though the quantization accuracy of the gain information slightly deteriorates, predictive gain β(j) need not be stored in the codebook, and this leads to a reduction of memory. Furthermore, the present invention is likewise applicable, for example, to a configuration in which the higher layer divides gain information by a gain value (predictive gain β(j) corresponds to this) statistically calculated from the gain information and quantizes the division result as an error component. Furthermore, since the amount of processing/calculation of the division increases in this case, a configuration may also, of course, be adopted in which the reciprocal of predictive gain β(j) is stored in the codebook beforehand and multiplication instead of division is performed when the division result is actually calculated. Furthermore, in this case, during decoding in the decoding apparatus, to correspond to the processing in the coding apparatus, a final decoding gain value is calculated by multiplying (or dividing) the decoding gain by predictive gain β(j) instead of adding predictive gain β(j) to the decoding gain.
[0112] A case has been described in the present embodiment as an example where the first layer coding section/decoding section adopts a CELP type coding/decoding method, but the present invention is not limited to this. The present invention is likewise applicable to a case where a coding method other than the CELP type or a coding method on the frequency axis is adopted. When the first layer coding section adopts a coding method on the frequency axis, may be possible to perform orthogonal transform processing on an input signal to first, then encode the low-frequency part and input the decoded spectrum obtained to the second layer coding section as is. This eliminates the necessity for processing in the down-sampling processing section, up-sampling processing section or the like in this case.
[0113] Furthermore, the decoding apparatus according to the present embodiment performs processing using coded information transmitted from the above-described coding apparatus. However, the present invention is not limited to this, and the decoding apparatus can perform processing on any type of coded information including necessary parameters or data even if it is not necessarily coded information from the above-described coding apparatus.
[0114] In addition, the present invention is also applicable to cases where this signal processing program is recorded and written on a machine-readable recording medium such as memory, disk, tape, CD, or DVD, achieving behavior and effects similar to those of the present embodiment.
[0115] Also, although cases have been described with Embodiment as an example where the present invention is configured by hardware, the present invention can also be realized by software.
[0116] Each function block employed in the description of Embodiment may typically be implemented as an LSI constituted by an integrated circuit. These may be implemented individually as single chips, or a single chip may incorporate some or all of them. Here, the term LSI has been used, but the terms IC, system LSI, super LSI, and ultra LSI may also be used according to differences in the degree of integration.
[0117] Further, the method of circuit integration is not limited to LSI, and implementation using dedicated circuitry or general purpose processors is also possible. After LSI manufacture, utilization of an FPGA (Field Programmable Gate Array) or a reconfigurable processor where connections and settings of circuit cells in an LSI can be reconfigured is also possible.
[0118] Further, if integrated circuit technology comes out to replace LSI as a result of the advancement of semiconductor technology or a derivative other technology, it is naturally also possible to carry out function block integration using this technology. Application of biotechnology is also possible.
[0119] The present invention contains the disclosures of the specification, the drawings, and the abstract of Japanese Patent Application No. 2009-258841 filed on Nov. 12, 2009, the entire contents of which being incorporated herein by reference.
INDUSTRIAL APPLICABILITY
[0120] When a technology (band extension technology) of performing band extension using a low-frequency spectrum to estimate a high-frequency spectrum is applied to a hierarchy coding/decoding scheme, the coding apparatus, decoding apparatus and the methods thereof according to the present invention can efficiently perform encoding in a higher layer as well, improve the quality of the decoded signal, and are suitable for use, for example, in a packet communication system or mobile communication system.
REFERENCE SIGNS LIST
[0000]
101 coding apparatus
102 transmission line
103 decoding apparatus
201 down-sampling processing section
202 first layer coding section
203 , 402 first layer decoding section
204 , 403 up-sampling processing section
205 , 404 , 408 orthogonal transform processing section
206 second layer coding section
207 , 405 second layer decoding section
208 , 209 , 407 adder
210 third layer coding section
211 coded information integration section
301 shape coding section
302 gain coding section
303 multiplexing section
401 coded information demultiplexing section
406 third layer decoding section
501 demultiplexing section
502 shape decoding section
503 gain decoding section | There is disclosed an encoder apparatus whereby, when a band expanding technique for encoding, based on the spectral data of a lower frequency portion, the spectral data of a higher frequency portion is applied to a lower layer in a hierarchical encoding/decoding system, an efficient encoding can be performed in an upper layer as well, thereby improving the decoded-signal quality. In an encoder apparatus ( 101 ), a second layer decoder unit ( 207 ) calculates a spectrum (differential spectrum), which is to be encoded in a third layer encoder unit ( 210 ) that is an upper layer of the second layer decoder unit ( 207 ), by applying such an ideal gain (first gain parameter a 1 ) that minimizes the energy of the differential spectrum. | 6 |
RELATED APPLICATION
[0001] This application is based on provisional application Ser. No. 60/197,189, filed Apr. 14, 2000.
FIELD OF INVENTION
[0002] The invention relates to lift systems for raising and lowering window blinds which have a cord lift system such as pleated shades, roman shades and venetian blinds.
BACKGROUND OF THE INVENTION
[0003] Venetian type blinds have a series of slats hung on ladders which extend from a headrail to a bottomrail. In most venetian blinds a pair of lift cords is provided each having one end attached to the bottomrail and then passing through elongated holes in the slats up to and through the headrail. When the lift cords are pulled downward the blind is raised and when the lift cords are released the blind is lowered. A cord lock is usually provided in the headrail through which the lift cords pass. The cord lock allows the user to maintain the blind in any desired position from fully raised to fully lowered. Pleated shades and roman shades are also raised and lowered by lift cords running from the bottom of the shade into a headrail. The cord lock system and other cord lift systems used in venetian blinds can also be used in pleated shades and roman shades.
[0004] Another type of lift system for window blinds utilizes a take-up tube for each lift cord. These tubes are contained on a common shaft within the headrail. Each lift cord is attached to one end of a tube. The tubes are rotated to wind or unwind the lift cord around tubes. This system is generally known as a tube lift system. One problem with tube lift systems of the prior art is that the tube may rotate faster than the cord is pulled away from the tube during lowering of the blind. This can occur when one end of the blind is prevented from moving downward as happens when the blind hits a piece of furniture that is too close to the window. That will cause the cord to bunch and often become tangled within the headrail. When this occurs it is usually enough to help the bottomrail with your hand to the bottom most position and then operate again. However, sometimes it is necessary to remove the blind from the window and untangle or replace the tangled lift cord. This is especially true when the capstan has a cone shape. There is a need for a tube lift system which is easy to operate and which will prevent the lift cords from becoming tangled when the blind is raised and lowered.
[0005] A second problem with tube lift systems arises from the fact that the diameter of the lift cords can vary by as much as five thousandths of an inch and the diameter of the tube or spool on which the lift cords are wrapped can vary by four thousandths of an inch. If a blind has two lift cords, each cord having a different diameter and each spool on which a lift cord is wound having a diameter different from the other spool, then it is possible that one lift cord will end up being longer than the other lift cord when the blind is lowered. This difference can be as much as one half to three fourths of an inch when the blind is fully lowered. Consequently, the bottomrail is noticeably slanted or uneven. Prior to the present invention the art had found no good solution to this problem. One solution was to shorten the cord which was longer when the blind was fully lowered so that the bottomrail appeared to be even when the blind was fully lowered. However, when that was done the bottomrail was slanted in an opposite direction when the blind was stacked. Another solution was to replace the lift cords. Depending upon how close the diameters of the replacement cords were to one another, this may or may not have been an improvement. Whatever the solution, the shade had to be disassembled and restrung. Consequently, there is a need for a cord lift system for blinds which can be adjusted to compensate for differences in diameters of lift cords and spools on which they are wound.
SUMMARY OF THE INVENTION
[0006] I provide a lift system for blinds of the type having at least one pair of lift cords for raising and lowering the blind. I prefer to provide a conical cord collector or cone for each center lift cord or each pair of lift cords that pass over the edge of the slats. I prefer that the cone be threaded. In an edge lift cord system two lift cords will lie side by side when wrapped around the cone. An axle passes through each externally threaded cone so that rotation of the axle will rotate the cones and the cones may slide along the axle or the axle will traverse the headrail. I prefer that the cones have a frusto-conical shape. I further prefer to provide a cover that surrounds at least a portion of each cone. This cover may be internally threaded. Optionally a drive wheel is positioned adjacent the cone which engages a lift cord as that lift cord is unwrapped from around the cone. The drive wheel is literally fixed relative to the headrail so that it is always adjacent where the lift cord enters the headrail space. At least one cone can be adjusted laterally and radially relative to the axle and the other cones so that the lift cord can effectively start wrapping on any diameter of the cone.
[0007] Other objects and advantages of the present invention will become apparent from a description of the present preferred embodiments shown in the drawings.
BRIEF DESCRIPTION OF THE FIGURES
[0008] [0008]FIG. 1 is a rear perspective view partially cut away of the present preferred embodiment of my lift system on a pleated shade shown in a near fully lowered positioned.
[0009] [0009]FIG. 2 is a sectional view taken along the line II-II of FIG. 1.
[0010] [0010]FIG. 3 is an enlarged view of a present preferred cone used in the embodiment shown in FIG. 1.
[0011] [0011]FIG. 4 is a sectional view taken along the line IV-IV of FIG. 1.
[0012] [0012]FIG. 5 is a rear perspective view of one end of the headrail partially cut away which contains a second present preferred embodiment of my lift system.
[0013] [0013]FIG. 6 is a perspective view of a conical cord collector and cover portion of a third present preferred embodiment of my lift system.
[0014] [0014]FIG. 7 is a perspective view of a portion of the lift system similar to that shown in FIG. 1 which utilizes a threaded axle and locking nuts with a position indicator.
[0015] [0015]FIG. 8 is a top plan view of the drive wheel in engagement with a portion of a conical cord collector.
[0016] [0016]FIG. 9 is a top plan view of another present preferred embodiment of my lift system.
[0017] [0017]FIG. 10 is a front view of a venetian type blind containing another present preferred embodiment of my lift system.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] The first present preferred embodiment of my lift system is contained in a headrail 2 , with endcaps 3 shown in FIG. 1. That lift system can operate a pleated shade 28 shown in FIG. 1 or other window covering attached to the headrail. The lift system has a central axle 5 which is turned by pulling cord loop 10 . One could provide an electric motor to turn the axle. The axle is carried on brackets 6 . As shown in FIG. 9, I prefer to provide threads 12 at one end of the shaft 5 . If desired one could use a release brake of the type disclosed in my U.S. Pat. Nos. 5,791,393 and 5,927,370 to turn the axle. That release brake is indicated by the box 13 in dotted line in FIG. 4. As can be seen in FIG. 1, each lift cord 9 is wound on a conical cord collector or cone 8 .
[0019] As shown most clearly in FIG. 3, I prefer that each cone have a series of stepped or threaded diameters 7 with the width of each step or thread being approximately the diameter of a standard lift cord, namely, 0.9 to 1.4 mm. As the lift cord 9 is wound about the cone the cord wraps on decreasingly smaller diameters of the cone. Referring to FIGS. 1 and 2, I further provide a guide wheel 16 carried on arm 17 . The lift cord 9 enters the headrail 2 through an eyelet 18 . The cord 9 is pressed against cone 8 by guide wheel 16 . A preferred wheel 16 shown in FIG. 8 has a rim 19 that presses the cord 9 against the cone 8 keeping the cord in a correct position. A spring 15 keeps the guide wheel 16 against the cone 8 . A clutch could also be provided. As the axle 5 is turned either the entire axle and attached cones move left or right within the headrail or the cones move left or right along the axle depending upon the direction in which the axle is rotated. The axle could be threaded at one end as shown in FIG. 9 to enable the axle to move or threaded at locations carrying cones to enable the cones to move on the axle. One could also provide a smooth shaft and allow the wrap of the cords to advance the cones along the axle. This movement presents a changing cone diameter to the guide wheel. Consequently, no two full rotations of the axle will wind or unwind the same length of cord.
[0020] An important advantage of the guide wheel arises from the wheel being driven by the cone as the blind is being lowered and by the cord as the blind is being raised. That means that the wheel will turn faster than the cord when it is being unwound from the cone and the blind is being lowered and at the same speed as the cord when the blind is being raised. This action drives the cord from the cone through the eyelet 18 and out of the headrail. Consequently, if the cone keeps turning while downward movement of the blind is obstructed, the excess cord is likely to be expelled from the headrail where it is less likely to tangle and easier to untangle.
[0021] In a standard tube lift the lift cord is wound about a cylindrical tube or cylindrical axle. Consequently, each rotation of the axle will collect or release a length of cord equal to the circumference of the tube which can be calculated from the equation L=πdw where d is the outside diameter of the tube plus the radial diameter of the cord as it wraps on the tube and w is the number of wraps. In blinds for standard residential and commercial windows the axle may rotate 40 or more times to fully raise or lower the blind. All window blinds that have lift cords will have at least two lift cords and each lift cord is wound on a separate portion of the tube or has its own spool. Although all tubes are supposed to have a consistent diameter, one portion of a tube is often larger than the other portions with differences in diameters being as much as 0.005 inches. The cord diameters can also vary by up to 0.005″. Since the spool will rotate about forty times to fully lower the blind, that means one lift cord could be lowered 0.4 inches more than the other lift cord. Hence the bottom of the shade will appear to be tilted.
[0022] In the present lift system the total length of lift cord that will be released is determined by the equation:
L=Σπd A w
[0023] wherein d A is the average diameter of the cone over which the cord winds and the diameter of the cord. Average diameter on a cone equals the largest diameter and the smallest diameter divided by two. It is desired to have the length L constant. The number of wraps will be the same for all of the cones since they are on the same axle. Therefore, the average diameter of the cone and the cord needs to be equal from cone to cone. Since the cones are likely to vary slightly from part to part and the cord diameters will also vary the average diameter d A can be equalized by adjusting the starting or largest diameter that cord begins wrapping on.
[0024] Because a cone offers a series of different diameters a fabricator can position the cones on the axle so that the lift cords begin wrapping at slightly different locations on the cones. Consequently, the fabricator can compensate for variations among cones and cords. The result is that every blind can be fabricated so that the bottom of the blind is level when the blind is fully lowered. The fabricator can adjust the position of the cord simply by rotating the cone relative to the axle and advancing it relative to the axle. For example, suppose the cone is shaped so that each thread is 0.030″ smaller or larger than the adjacent thread and that there are two cones used in the blind. Also suppose that one cone′ is 0.005″ smaller in diameter than the other and also that the cord wrapping on that cone is 0.005″ smaller in diameter. If the cords were started in exactly the same spot on both cones then L′=Σπd′ A w<L=Σπd A w because d′ A would be 0.010″ smaller than d A . Rotating either cone 120° or 1/3 of a wrap and advancing it 1/3 of the travel of one thread would compensate for the difference and L=L′.
[0025] I prefer to provide a cover that surrounds the cone as shown in FIGS. 5 and 6. The cover may be a rectangular or cylindrical housing 20 which fits around and is spaced apart from the cone as shown in FIG. 5. Alternatively, the housing 22 may be frusto-conical and have interior threads or shoulders 23 which match the stepped diameters 7 of cone 8 such as shown in FIG. 6. In the event that an obstruction prevents the bottom of the blind from falling, axle 5 may continue to turn. Should that happen, the lift cords would continue to unwrap from the cone. Since there is no force pulling the lift cord from the headrail the excess cord will remain in the cover in the headrail. If there are no covers that excess lift cord could easily get caught on a bracket or other structure in the headrail. Additionally, the excess cord could become tangled on itself forming a “nest” of cord within the headrail. It is then necessary to open the headrail to untangle the lift cords. Sometimes the lift cords must be replaced. The covers shown in FIGS. 5 and 6 overcome this problem by capturing the unwinding cord. In limited tests I have found that should a blind encounter an obstruction when descending thereby creating unwound cord in the headrail, the problem can be corrected by removing the obstruction and fully lowering the blind. It is not necessary to open the headrail or replace the cords. A partial cover may also be used. One such partial cover would appear like segment 21 of cover 22 shown in dotted line in FIG. 6. The segment may be fixed to prevent transverse movement but be able to move radially toward and away from the cone.
[0026] In yet another embodiment of the lift system shown in FIG. 7 the cone 8 is held on a threaded axle 30 . Lock nuts 31 and 32 are provided on the axle 30 at either end of the cone 8 to retain the cone in a desired location. One could also use a threaded collet and nut or a simple spring clutch between each cone and a corresponding fixed collar on a non-round axle. In FIG. 7, I provide a series of spaced apart marks 34 on nut 32 . I further prefer to provide a longitudinal reference line 35 on shaft 30 . This line could be a groove cut in the threads. When the blind is initially fabricated the cone 8 is positioned so that the zero line 36 is aligned with reference line 35 . If it is necessary to adjust the position of the cone 8 , a fabricator can turn nut 31 a distance that can be measured by the markings 34 on nut 32 . Of course, if nut 32 is turned, nut 31 would be turned an equal amount to prevent slippage of the cone 8 along the axle 30 .
[0027] Another embodiment of my lift system shown in FIG. 9 has two axles. The first axle 40 contains a cone 48 . The second axle 42 contains a collection spool 44 . Both axles are held within the headrail 2 on brackets 43 . Only the cylinder axle is powered with a drive mechanism 41 that can be operated with a cord loop, wand or pull cord (not shown). The cones and axle are rotated by the cords. The lift cord 8 wraps around a selected diameter of the cone 48 and then is collected on spool 44 . In the event that the bottom of a blind is not level when the blind is fully lowered, the fabricator can shift one of the cones 48 so that the lift cord leaves the spool at a different diameter. Consequently, the path of one lift cord over a cone onto a spool will be longer than the same path of another cord. If desired the lift cord may make multiple wraps around the cone 48 before moving onto the spool 44 .
[0028] In all of the lift systems illustrated in FIGS. 1 through 9 there has been a single lift cord at each cone location. The present lift system is not limited to such blinds but can also be used in a blind having pairs of lift cords such as the venetian blind shown in FIG. 10.
[0029] In such a blind, lift cords are positioned near either end of the blind in slots on both the front and rear edges of the slats. In the embodiment of FIG. 10 four lift cords extend from the bottomrail (not shown) through the headrail. Lift cords 81 and 83 extend from the bottomrail through slots 67 in the front edge of slats Lift cords 82 and 84 extend from the bottomrail through slots in the rear edge of slats 66 . Each pair of lift cords 81 , 82 , 83 and 84 pass through the headrail 2 . Each pair of lift cords 81 , 82 or 83 , 84 are directed through the headrail over an eyelet 68 onto a cone 8 provided in the headrail. Each pair of cords is wrapped side by side on each stepped diameter of the cone 8 .
[0030] A lateral tilt mechanism 56 is provided to move the rails 51 and 52 of the tilt ladder 50 relative to one another to open and close the blind. The tilt mechanism in the preferred embodiment is comprised of a strap 58 to which the rails of the tilt ladder 50 are connected. This type of lateral tilt system is disclosed in my U.S. Pat. No. 5,778,956. The strap 58 is carried on pulleys 59 . A handle 55 is turned to open and close the blind. The handle 55 is connected to a gear box 53 that operates an end pulley at the gear box. Turning wand 55 causes the end pulley 59 to turn and move the strap. Movement of the strap 58 in either direction lifts one rail relative to the other to open and close the blind.
[0031] Although I have shown and described certain present preferred embodiments of my venetian blind it should be distinctly understood that the invention is not limited thereto but may be variously embodied within the scope of the following claims. | An axle driven cord collection system that uses cones to spool the lift cords. An idle/drive wheel on each cone prevents the cords from tangling. A collet connects each cone in an adjustable way so that the total travel of each cord can be precisely controlled by adjusting the position of the starting wrap on at least one of the cones. | 4 |
RELATED APPLICATIONS AND PRIORITY CLAIM
[0001] This divisional application claims priority to U.S. Ser. No. 61/149,064 a provisional application filed Feb. 2, 2009, U.S. Ser. No. 12/684,740 a non-provisional application filed Jan. 8, 2010. Each of these applications is incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to pivoting or rotary shelving systems, and more specifically, to a pivoting storage apparatus that is adapted to refrigerators or any other structure possessing horizontal generally rectangular storage surfaces. A portion of pivoting storage apparatus is able to be manually drawn out of the confines of the storage structure's interior by a user, thereby enabling easy access to shelf contents thereon.
BACKGROUND OF THE INVENTION
[0003] Even though the use and advantages of various rotary or pivoting storage devices applied to storage structures are known, there remain voids regarding desirable attributes pertaining to such rotary or pivoting storage devices, their methods of use, as well as solving and/or overcoming the underlining motives that prompts their use.
[0004] The following are related art examples of rotary or pivoting shelving systems for use in storage structures such as cabinets, refrigerators, and the like. For example, U.S. Pat. No. 3,172,715 to Powder and U.S. Pat. No. 2,692,813 to Toronto disclose shelving systems that require a pivoting joint assembly capable of bearing essentially the full load of the mobile shelf and its contents. Such systems require complex, heavy-duty, space consuming, hardware. In addition, the refrigerator side walls must be capable or configured to accept such mounting hardware as well as possessing the strength to tolerate such loads.
[0005] Both U.S. Pat. No. 5,810,462 to Lee and U.S. Pat. No. 1,899,171 to Warren describe shelving systems that call for several regions of attachment or points of support, including a refrigerator side wall, back wall, and a required support joint type connection affixed to the refrigerator's front door. The required connection to the front door mandates that the load burden of the mobile shelf and its contents are manipulated by a user during every door opening episode. Furthermore, the entire contents residing on the shelf are removed from the climate controlled interior of the refrigerator to the outside environment during each door open/close cycle, compounding the opportunity for thermal loss, food spoilage, and the like.
[0006] U.S. Pat. No. 5,577,823 to Maglinger discloses a shelving system that utilizes a pull-out drawer member incorporating a full round rotating storage container having a bottom with attached side walls. The container's circular shape results in a loss of available storage area in comparison to the available rectangular storage footprint where such a unit would typically reside. In addition, due to the absence of a home position (commonly lacking in full round rotating storage units), the relative arrangement of stored objects is not maintained from one visit to the next. Additionally, the apparatus creates an awkward accessibility scenario where the drawer unit must be maneuvered to the extreme forward extended position before complete accessibility to container contents, via a top opening, is possible.
[0007] The purpose of the present invention is to overcome several shortcomings in the aforementioned prior art as well as the introduction of additional novel features.
SUMMARY OF THE INVENTION
[0008] The present invention is directed toward a pivoting storage apparatus, and more specifically, to a pivoting storage apparatus that is adapted to storage structures of generally rectilinear geometry having generally rectangular interior storage surfaces, such as cabinets, refrigerators, and the like. The basic system is comprised of a pivoting main tray connected to the top of a flat base that is attached to a substantially fixed feature comprising a storage structure (e.g. a shelf, side walls, a back wall). The main tray component of the pivoting storage apparatus is capable of being manually drawn out of the confines of the structure's interior by a user, thereby enabling easy access to shelf contents thereon.
[0009] The basic method of retrieving object(s) resting on the pivoting storage apparatus comprises the steps of opening the door(s) of the storage structure, extending the main tray forward from its home position, locating and retrieving the object(s) of interest, closing or returning the main tray to its home position, and closing the storage structure's door(s).
[0010] Accordingly, a primary object of the present invention is to provide a quadrant shaped, pie shaped, or a sector shaped pivoting storage shelf assembly, configured for quick simple attachment to an existing surface, such as a shelf; as well as the ability to be affixed to standard mounting structures such as slots, slotted track, and the like, typically found in refrigerators, cabinets, and the like.
[0011] Another object of the present invention is to maximize the efficient use of storage space pertaining to the commonly utilized rectangular storage footprint.
[0012] Yet another object of the present invention is to maintain the relative location of stored objects with respect to each other and with respect to the storage structure environment. The preservation of object placement operates in conjunction with the pivoting storage feature of the present invention providing easy access to stored contents as well as an unchanging storage surface to promote easy item location via memory recall.
[0013] Whereas there may be many embodiments of the present invention, each embodiment may meet one or more of the foregoing recited objects in any combination. It is not intended that each embodiment will necessarily meet each objective.
[0014] Thus, having broadly outlined the more important features of the present invention in order that the detailed description thereof may be better understood, and that the present contribution to the art may be better appreciated, there are, of course, additional features of the present invention that will be described herein and will form a part of the subject matter of the claim(s) appended to this specification.
[0015] In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The present invention is capable of other embodiments and of being practiced and carried out in various ways.
[0016] As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the description be regarded as including such equivalent construction insofar as they do not depart from the spirit and scope of the conception regarded as the present invention.
PARTICULAR ADVANTAGES OF THE INVENTION
[0017] The present invention provides several advantages, including simple attachment to storage surfaces, such as racks, shelving, and the like located in refrigerators, cabinets and the like. The storage surface can be of the solid type (e.g. continuous sheet of glass or plastic), or the open area variety (e.g. wire rack, perforated metal or plastic). Additionally, the present invention of configured to make efficient use of the commonly found rectangular storage footprint typically found in storage structures. The unique pivoting feature in combination with a corner tray outperforms simple full round rotating storage units. Such full round rotating storage units (i.e. revolving servers or Lazy Susans) are plagued with undesirable attributes such as inherent storage losses, central dead spot issues, and the loss of relative arrangement of stored objects.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The invention will be described by reference to the specification and the drawings, in which like numerals refer to like elements, and wherein:
[0019] FIG. 1A shows a perspective top view of a pivoting storage apparatus in accordance with one embodiment having an attached corner tray.
[0020] FIG. 1B shows an orthogonal top view of a pivoting storage apparatus in accordance with the embodiment of FIG. 1A
[0021] FIG. 1C shows an orthogonal side view of a pivoting storage apparatus in accordance with the embodiment of FIG. 1A .
[0022] FIG. 1D shows an orthogonal bottom view of the pivoting storage apparatus in accordance with the embodiment of FIG. 1A .
[0023] FIG. 1E shows a partial cutaway side view of the pivoting storage apparatus in accordance with the embodiment of FIG. 1A .
[0024] FIG. 2 is an exploded perspective view of the embodiment shown in FIG. 1A depicting additional detail.
[0025] FIG. 3A shows a perspective top view of the base corresponding to the embodiment shown in FIG. 1A .
[0026] FIG. 3B shows an orthogonal top view of the base corresponding to the embodiment shown in FIG. 1A .
[0027] FIG. 3C shows a perspective top view of an alternate embodiment of a base having an integrated corner tray. Also depicted are examples of various means of attaching the base to open type of shelving (e.g. wire rack and the like).
[0028] FIG. 3D shows a perspective bottom view of an alternate embodiment of a base to a main tray pivoting system.
[0029] FIG. 4A shows an orthogonal top view of a main tray of a pivoting storage apparatus in accordance with one embodiment.
[0030] FIG. 4B shows a perspective top view of a main tray of a pivoting storage apparatus in accordance with one embodiment.
[0031] FIG. 4C shows an orthogonal side view of a main tray of a pivoting storage apparatus in accordance with one embodiment.
[0032] FIG. 4D shows an orthogonal bottom view of a main tray of a pivoting storage apparatus in accordance with one embodiment.
[0033] FIG. 5A shows an orthogonal top view of a corner tray of a pivoting storage apparatus in accordance with one embodiment.
[0034] FIG. 5B shows a perspective bottom view of a corner tray of a pivoting storage apparatus in accordance with one embodiment.
[0035] FIG. 5C shows an orthogonal bottom view of a corner tray of a pivoting storage apparatus in accordance with one embodiment.
[0036] FIG. 6A illustrates an orthogonal top view of two adjacent pivoting storage devices showing clockwise and counterclockwise mounting schemes in a typical storage environment having a generally rectangular geometry and two opposing doors.
[0037] FIG. 6B illustrates an orthogonal top view of two adjacent pivoting storage devices, with the left storage device pivoted in the open position, showing clockwise and counterclockwise mounting schemes in a typical storage environment having a generally rectangular geometry and two opposing doors.
[0038] FIG. 7A shows a perspective top view of a pivoting storage apparatus in accordance with an alternate embodiment having two support arms configured to mount to a pair of vertical rails having periodic mounting slots.
[0039] FIG. 7B shows an orthogonal top view of a pivoting storage apparatus in accordance with the alternate embodiment of FIG. 7A .
[0040] FIG. 7C shows an orthogonal side view of a support arm used in accordance with the alternate embodiment of FIG. 7A .
[0041] FIG. 7D shows an orthogonal bottom view of a pivoting storage apparatus in accordance with the alternate embodiment of FIG. 7A .
[0042] FIG. 8A shows a perspective top view of a pivoting storage apparatus in accordance with an alternate embodiment having a side rail mounting scheme configured to mount into a storage structure having corresponding horizontal slotted rail pairs on each of the two opposing side walls.
[0043] FIG. 8B shows an orthogonal top view of a pivoting storage apparatus in accordance with the alternate embodiment of FIG. 8A .
[0044] FIG. 8C shows an orthogonal bottom view of a pivoting storage apparatus in accordance with the alternate embodiment of FIG. 8A .
[0045] FIG. 9A shows a perspective top view of a standalone corner tray container.
[0046] FIG. 9B shows a perspective top view of a standalone corner tray container resting on the corner tray portion of one embodiment of a pivoting storage apparatus.
[0047] FIG. 9C shows an orthogonal top view of a standalone corner tray container resting on the corner tray portion of one embodiment of a pivoting storage apparatus.
[0048] The drawings are not to scale, in fact, some aspects have been emphasized for a better illustration and understanding of the written description.
Parts List For Pivoting Storage Apparatus
[0000]
110 . Pivoting storage apparatus
112 . Main Tray
114 . Corner Tray
114 a . Integrated corner tray
116 . Mating Interface
118 . Corner Based Pivot Point
120 . Assembly First Side Dimension
122 . Assembly Second Side Dimension
124 . Bottom Surface (Base)
126 . Slide Edge Cavity
128 . First Edge (Main Tray)
130 . Second Edge (Main Tray)
210 . Main Tray Pivot Fastener Receiver
212 . Main Tray pivot Aperture
214 . Base Pivot Fastener
216 . Resting Surface Fasteners (Suction Cups)
218 . Base Corner Tray Fasteners
310 . Base
311 . Base retaining lip
310 a . Alternate base
312 . Locking receptacles
312 a . Fastening receptacles
312 b . Detail of fastening receptacles
313 . Base pivoting corner
314 . Base-Corner Tray Apertures
315 . Alternate fasteners
315 a . Tie wrap
315 b . Twist tie
315 c . Nut, bolt, and washer
316 . Base pivot aperture
316 a . Integrated base pivot aperture lip
316 b . Integrated main tray tabs
318 . Base Width
320 . Base Length
322 . First Stop Post
324 . Second Stop Post
326 . Channel
328 . Top Surface
330 . Elevated Surface
410 . Main Tray Ribs
412 . Vertical Wall
413 . Main tray pivoting corner
414 . First Stop Tab
416 . Second Stop Tab
418 . Slide Edge
420 . Main Tray First Edge Dimension
422 . Main Tray Second Edge Dimension
424 . Main Tray First Edge
426 . Main Tray Second Edge
428 . Arciformed Edge
430 . Bottom Surface
510 . Corner Tray Top Surface
512 . Retaining Lip
514 . Base Fastener Receptacles
515 . Corner Tray Bottom Surface
516 . Positioning Member
518 . Corner Tray First Side
520 . Corner Tray Second Side
610 . Resting Surface
612 . Support Member
614 . Storage Structure
616 . Clockwise Mounting
618 . Counterclockwise Mounting
620 . Clockwise Arc Trajectory
622 . Counterclockwise Arc Trajectory
624 . Left Door
626 . Right Door
628 . Left Side Wall
630 . Right Side Wall
632 . Back Wall
634 . Open Position
710 . Back Wall
712 . Left Slotted Track
714 . Right Slotted Track
716 . Pivoting Storage Apparatus (with Support Brackets)
716 a . Bottom of Pivoting Storage Apparatus
718 . Left Support Bracket
720 . Right Support Bracket
722 . Bracket Mounting Holes
724 . Mounting Tabs
726 . Clockwise Mounting Holes
728 . Counterclockwise Mounting Holes
730 . Support Bracket
810 . Right Side Wall
812 . Left Side Wall
814 . Interior
816 . Storage Structure
818 . Back Wall
820 . Left Slot
822 . Right Slot
824 . Pivoting storage apparatus (with Side Rails)
826 . Left Rail
828 . Right Rail
830 . Rectangular Base
832 . Bottom (of Base)
900 . Corner tray container
902 . Corner tray container cover
902 a . Corner tray container cover aperture
904 . Corner tray container bottom
906 . Container bottom
910 . First main tray handle
911 a . First main tray edge
911 b . Second main tray edge
912 . Second main tray handle
914 . Main tray
[0154] It is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
Definitions Of Terms Used In This Specification
[0155] The pivoting storage apparatus adapted to rectilinear structures aforementioned shall have equivalent nomenclature including: the pivoting storage apparatus, the device, the present invention, or the invention. Also, the term rectangular is understood to include case where all sides of the geometric shape are of equal length, also known as an equilateral rectangle or a square.
[0156] As used in the this specification, the term pie-cut, quadrant shape, sector shape, sector-cut, or ninety degree sector shape, shall be defined by the ordinary mathematical meaning of a “sector” defined by the region of a circle formed by two radii and their intercepted arc, where the angle between the two radii, in the present invention, is about 90 degrees. Additionally, the term “exemplary” shall possess only one meaning in this disclosure; wherein the term “exemplary” shall mean: serving as an example, instance, or illustration.
DETAILED DESCRIPTION OF THE INVENTION
[0157] The first embodiment of the pivoting storage apparatus 110 having a separate corner tray 114 is depicted in FIGS. 1A to 1E , FIG. 2 , FIGS. 3A and 3B , FIGS. 4A to 4D , FIGS. 5A to 5C . This embodiment is configured to be used as an accessory type device for use in storage structures such as refrigerators, cabinets, and the like, to facilitate object manipulation. The device is intended to function as a removeably attachable storage aid or accessory, and is depicted as an accessory mounted on resting surface 610 of existing support member 612 located in storage structure 614 , as depicted in FIGS. 6A and 6B . The existing support member 612 provides a resting surface 610 , and includes shelves, racks, ledges, and the like.
[0158] FIGS. 1A and 1B depict a perspective top view and an orthogonal top view of the pivoting storage apparatus 110 respectively showing main tray 112 having sliding relationship with corner tray 114 via mating interface 116 (see FIG. 1E for detail) and pivoting corner 118 . Referring to FIG. 1E , it is understood that sliding edge cavity 126 with retaining lip 512 are not corner tray 114 required features, alternatively, such features can be incorporated into base 310 ; in such a system, corner tray 114 becomes an optional component of pivoting storage apparatus 110 .
[0159] It is well known that the center of rotation or pivot point of a circular planar object, such as a disk, is a location characterized by little to no relative movement as the circular planar object is rotated about the pivot point. Therefore, access to a centrally located object(s) stored on a full round rotating type devices (e.g. Lazy Susans) is not substantially improved by the rotation of such devices. As can be seen in FIGS. 1A and 1B , the present invention's pivot point is not centrally located, but positioned on a corner based pivot point 118 locations. Referring to FIG. 6A , when pivoting storage apparatus 110 is mounted such that corner based pivot points 118 are positioned on the accessible front portion of an existing support member 612 , the accessibility dead spots on main tray 112 are essentially eliminated. The accessibility of centrally located objects on a full round rotating unit is not substantially improved by the rotation of the unit due to the center of rotation residing at the geometrical center of the unit; whereas in the present invention, the center of rotation is configured to reside on a front corner of the device when installed, thereby overcoming the inaccessibility issue.
[0160] Furthermore, the relative arrangement of stored objects on the present invention is maintained (unlike full round rotating units lacking a home position); this feature may be of particular interest to those who prefer such spatial reproducibility (e.g. visually impaired, elderly, and the like).
[0161] FIG. 2 depicts an exploded perspective view of pivoting shelving assembly 110 that is adapted to resting surface 610 of support member 612 (e.g. refrigerator rack, cabinet shelf, and the like) of FIG. 6A . The pivoting shelving assembly 110 includes a base 310 , having a generally planar geometry, that contains an array of locking receptacles 312 integrated into base 310 , accessible via bottom surface 124 of base 310 (bottom view best depicted in FIG. 1D ). Locking receptacles 312 are configured to accommodate resting surface fasteners 216 that are of the suction cup variety and the like. The function of resting surface fasteners 216 of the suction cup variety is to attach the device to typical continuous smooth surfaces such as refrigerator racks, cabinet shelves, fabricated from smooth glass, plastic, or the like. Resting surface fasteners 216 depicted, are in the form of suction cups configured to firmly adhere to smooth flat surfaces commonly used in shelving associated with refrigeration type appliances and the like. Such suction cup type devices are commonly fabricated from pliable polymeric type materials.
[0162] Alternate means of attaching the device are depicted in FIG. 3C . Fastening receptacles 312 a are shown as a generally rectangular aperture in alternate base 310 a , but are not limited to such geometry. Fastening receptacles 312 a are adapted to cooperate with alternate fasteners 315 that are configured to cooperate with a support member 612 having a resting surface 610 that possesses large open areas (e.g. wire racks, shelving with perforation type patterns, or the like) where suction cups type fasteners would not properly function. Alternate fasteners 315 include a plurality of tie wraps 315 a , twist ties 315 b , nut, bolt, and washer 315 c assemblies, or any combination thereof. Note that in preferred embodiments, the uses of fasteners that are removeably attachable are preferred so that the pivoting storage apparatus can be removed to facilitate the cleaning of the device as well as the surrounding storage area(s). Therefore, the use of the particular type of tie wraps 315 a , having a release tab is preferable for the aforementioned reasons as well as to enable the reuse of such fasteners. Aperture geometries other than rectangular, for example circular, are understood to better cooperate with cylindrical type fasteners such as bolts, and are therefore are considered to be a viable option. Additionally, it is understood that other fastener methodologies (e.g. hook and loop, magnetic, and the like) can be used to secure the storage device to a variety of surface types, such fastening means are well known in the fastening arts.
[0163] Referring to FIG. 1D , resting surface fasteners 216 , depicted in the form of suction cups, are removeably attached to locking receptacles 312 in a positive locking manner, thereby substantially immobilizing the fasteners and securing them to base 310 . This is due, in part, to locking receptacles 312 having a figure eight configuration that enables the accommodation of suction cups 216 in a non-permanent manner. The nonpermanent attachment scheme facilitates suction cup replacement as they deteriorate, as well as enabling easy device removal from service.
[0164] Again referring to FIG. 2 , main tray 112 is pivotally attached to the top surface 328 of base 310 via a base pivot fastener 214 passing through both base pivot aperture 316 and main tray pivot aperture 212 , closing the pivoting joint with a main tray fastener receiver 210 . Base pivot fastener 214 and main tray fastener receiver 210 combination can be chosen from a variety of well known fastener technologies (e.g. nut and bolt, snap-fit, etc.). It is desirable to utilize a fastener technology that is easily unfastened to enable disassembly of the device to promote clean-up due to spills and the like. FIG. 3D depicts an integrated pivoting system where base pivot aperture lip 316 a feature is fabricated as an integral part of alternate base 310 a (shown in FIG. 3C ) is configured to pivotally cooperate with integrated main tray tabs 316 b . Such a pivoting system having integrated components provides a cost effective pivoting means capable of fast and easy assembly as well as disassembly. The integrated pivoting system of FIG. 3 d reveals one possible pivoting system embodiment where integrated main tray tabs 316 b are depicted as a plurality of tabs. The plurality of tabs can be configured to snap-fit into place, or provide simple nesting; additionally the plurality of tabs can be replaced with a full circle continuous ring, or the like. It is understood that there exists a myriad of viable equivalent pivoting system embodiments that are capable of satisfactory performance given the pivoting application.
[0165] Again referring to FIG. 2 , main tray 112 possesses a ninety degree sector shape having a first edge 128 that is perpendicular to a second edge 130 , further possessing a third curved or arciformed edge 428 , having a slide edge 418 . Corner tray 114 is attached to base 310 using base-corner tray fasteners 218 passing through base-corner tray apertures 314 and fastening to base fastener receptacles 514 located on the bottom of corner tray (best depicted in FIG. 5C ). Retaining lip 512 of corner tray 114 forms a slide edge cavity 126 (best depicted in FIG. 1E ) with base 310 where slide edge 418 of main tray 112 is allowed pivoting movement while simultaneously providing confining support within the geometric plane. It is understood that the retaining lip 512 feature comprising the slidably mating interface (best shown in FIG. 1E ), is not limited to the present configuration. In the present configuration, retaining lip 512 is integrated into corner tray 114 as depicted in FIG. 2 . The retaining lip 512 feature can alternatively be attached or constitute an integral feature of base 310 as depicted in FIG. 3 c where base retaining lip 311 is integrated into base 310 .
[0166] FIGS. 3A and 3B show a perspective top view and an orthogonal top view of base 310 , respectively. Base 310 exemplary dimensions for the embodiment shown in FIG. 3 a , include: base width 318 range from 23.0 cm to 43.0 cm, base length 320 from 42.0 cm to 62.0 cm. FIG. 3B shows additional details of top surface 328 of base 310 , including a first stop post 322 and a second stop post 324 which is designed to interface with main tray 112 bottom surface 430 first stop tab 414 and second stop tab 416 respectively (depicted in FIG. 4D ); such features provide travel limits that prevent or safeguard main tray 112 from over extension. The present configuration of FIG. 4D shows first stop tab 414 and second stop tab 416 attached to one of a plurality of main tray ribs 410 attached to bottom surface 430 of main tray 112 . In the device's fully assembled state, first stop tab 414 and second stop tab 416 are configured to cooperate with mating first stop post 322 and second stop post 324 respectively; where first stop post 322 and second stop post 324 are disposed into at least one predetermined channel 326 located on top surface 328 of base 310 . The depiction is intended to be understood as one of many possible arrangements to provide travel limit protection.
[0167] The plurality of channels 326 and plurality of elevated surfaces 330 provide base 310 with a corrugated like geometry, such a geometry supplies base 310 structure with additional strength in addition to providing a reduced friction sliding surface. In the situation where the reduction of sliding surface friction is the sole concern (additional base strength is not an issue), there exist additional geometries or features to accomplish the friction reducing task (e.g. bumps, pads, and the like). The reduced friction sliding surface is created by one or more protuberances; these protuberances decrease the surface area between base 310 top surface 328 and interfacing bottom surface 430 of main tray 112 . In alternate embodiments, the protuberances can exist solely on base 310 top surface 328 or interfacing bottom surface 430 of main tray 112 , or any combination thereof; including the situation where base 310 top surface 328 and interfacing bottom surface 430 of main tray 112 both possess friction reducing protuberances.
[0168] Friction reducing protuberances are understood to be constructed from a plurality of elevated features that are not limited to the configurations disclosed. Other possible friction reducing configurations include: rails, posts, periodic high/low surface profiles, random protuberances, and the like. Rail and or channel type protuberances and the like, provide the additional advantage of boosting stiffening properties when applied to base 310 and/or main tray 112 type configurations.
[0169] FIG. 3C depicts alternate base 310 a configuration having an improvement where the alternate embodiment possesses an integrated corner tray 114 a . In preferred renderings of such an embodiment, integrated corner tray 114 a and alternate base 310 a would be fabricated as a single unit in a given manufacturing process (e.g. injection molding).
[0170] Base 310 a depicts two fastening receptacles 312 a (best depicted in detail of fastening receptacles 312 b ); each receptacle having an aperture that is configured to cooperate with a variety of fasteners that are designed to attach to open area shelving types (e.g. wire rack, perforated metal or plastic). Examples of such fasteners that are designed to attach the present invention to open area type of shelving are depicted as alternate fasteners 315 . One such fastener is tie wrap 315 a that provides a ratchet-like closure; preferred versions of tie wrap 315 a include those with release tabs that enable the tie to be released and subsequently reused. Another type of fastener is twist tie 315 b ; variations include simple wire, plastic coated metallic wire, and the like. Yet another type of fastener is the common nut, bolt, and washer 315 c . The basic structures and methods of attachment of the aforementioned attaching schemes are well known.
[0171] FIG. 3D depicts alternate base 310 a configuration having an alternate pivoting scheme where the alternate embodiment incorporates a base pivot aperture 316 having integrated base pivot aperture lip 316 a configured to pivotally cooperate with a main tray having integrated main tray tabs 316 b . The disclosed pivoting scheme, and its equivalents, allows the fastening components to be integrated into their respective base and main trap parent members, thereby providing a removeably attachable assembly having fewer individual parts.
[0172] FIGS. 4A to 4D show various views and aspects of the main tray 112 . Additional details of main tray 112 include a vertical wall 412 best shown in FIG. 4B that provides a means for stiffening main tray 112 as well as furnishing an optionally continuous elevated perimeter to help contain spills and the like. When vertical wall 412 is solely used as a means for stiffening main tray 112 , a portion of the main tray perimeter possessing vertical wall 412 may suffice depending upon the device application. Variations of the present configuration include providing a vertical wall 412 for main tray first edge 424 , main tray second edge 426 , arciformed edge 428 , or any combination thereof.
[0173] Similar to base 310 , the plurality of ribs 410 located on bottom surface 430 of main tray 112 provides main tray 112 with a corrugated like geometry, supplying main tray 112 a structure having additional strength or rigidity in addition to a reduced friction sliding surface. Since main tray 112 is the component that is pivoted forward resulting in a freestanding type condition, providing additional structure that increases strength or rigidity will help main tray 112 maintain a flat, planar profile under loaded conditions. In the situation where the reduction of sliding surface friction is the sole concern (additional base strength is not an issue), there exist additional geometries or features to accomplish the friction reducing task (e.g. bumps, pads, and the like). The reduced friction sliding surface is created by one or more protuberances; these protuberances decrease the surface area between base 310 top surface 328 and interfacing bottom surface 430 of main tray 112 . In alternate embodiments, the protuberances can exist solely on base 310 top surface 328 or interfacing bottom surface 430 of main tray 112 , or any combination thereof; including the situation where base 310 top surface 328 and interfacing bottom surface 430 of main tray 112 both possess friction reducing protuberances. Friction reducing protuberances are understood to be constructed from a plurality of elevated features that are not limited to the configurations disclosed. Other possible friction reducing configurations include: rails, posts, periodic high/low surface profiles, random protuberances, and the like. Substantially continuous structures such as rails, channels, and the like, type of protuberances provide the additional advantage of increasing strength, more specifically boosting stiffening properties when disposed to base 310 and/or main tray 112 members. Other possible friction reducing configurations include: rails, posts, periodic high/low surface profiles, random protuberances, and the like.
[0174] Exemplary main tray 112 dimensions of the embodiment of FIG. 4A include: main tray first edge dimension 420 range from 29.0 cm to 39.0 cm, main tray second edge dimension 422 range from 29.0 cm to 39.0 cm, where the two aforementioned dimensions are substantially equal. Note that assembly first side dimension 120 and assembly second side dimension 122 depicted in FIG. 1B share the same dimensional attributes as main tray first edge dimension 420 and main tray second edge dimension 422 due to the generally square geometry of the device. The generally flat nature of the device is revealed in side view illustration FIG. 4C in addition to side view depicted in FIG. 1C .
[0175] FIGS. 5A to 5C show various views and aspects of the corner tray 114 . Additional details of corner tray 114 include a positioning member 516 located on corner tray bottom surface 515 , shown in FIGS. 5B and 5C . Positioning member 516 provides assistance in properly aligning corner tray 114 to the other device elements during assembly. Exemplary corner tray 114 dimensions of the embodiment depicted in FIG. 5A include: corner tray first side 518 dimension ranges from 15.0 cm to 35.0 cm, corner tray second side 520 dimension ranges from 15.0 cm to 35.0 cm, where the two aforementioned dimensions can differ. Additionally, in order to ensure proper main tray 112 support, it is recommended that the radius of curvature of retaining lip 512 of corner tray 114 be substantially equal to that of arciformed edge 428 of main tray 112 of FIG. 4A to ensure adequate engagement as depicted in FIGS. 1B and 1E .
[0176] Referring to FIGS. 6A and 6B , the pivoting storage apparatus 110 has two possible mounting orientations, clockwise mounting 616 corresponding to clockwise arc trajectory 620 , and counterclockwise mounting 618 corresponding to counterclockwise arc trajectory 622 . The two mounting options 616 and 618 provide a default closing scheme for main tray 112 when the clockwise and counterclockwise arc trajectories correspond with those of left door 624 and right door 626 respectively. The closing of left door 624 and/or right door 626 will help move the corresponding main tray 112 of corresponding devices left in the open position 634 , safely return toward its closed (home) position. FIG. 6B depicts the present invention having clockwise mounting 616 with the main tray 112 in open position 634 . In order for the device to furnish the two aforementioned mounting orientations depicted in FIG. 6A , (i.e. clockwise mounting 616 with associated clockwise arc trajectory 620 , and counterclockwise mounting 618 with associated counterclockwise arc trajectory 622 ) it is recommended that main tray 112 be substantially modeled after a sector shape, where the term “sector shape” is characterized by the ordinary mathematical meaning of a “sector” that's defined by the region of a circle formed by two radii and their intercepted arc, where the angle between the two radii, in the present invention, is about 90 degrees.
[0177] Referring to FIGS. 6A and 6B , both the pivoting storage apparatuses 110 associated with the two mounting orientations, in an alternate embodiment, are either temporarily or permanently attached to each other. Such a pivoting storage configuration will provide the advantages of a seamless or joined construction which include a larger, sturdier device that provides increased storage.
[0178] FIGS. 7A to 7D show various views and aspects of another embodiment consisting of a pivoting storage apparatus 716 with support brackets 718 , 720 that are adapted for mounting onto a slotted track 712 and 714 respectively. For example, the slotted track 712 and 714 can be mounted onto a back wall 632 of storage structure 614 (shown in FIG. 6A ) which can represent cabinets, refrigerators, and the like.
[0179] In FIG. 7C , support bracket 730 depicts mounting tabs 724 that removably attach to slotted tracks 712 and 714 of FIG. 7A . Support brackets 718 and 720 of FIG. 7A possess a plurality of bracket mounting holes that align with both clockwise mounting holes 726 and counterclockwise mounting holes 728 located on bottom of pivoting storage apparatus 716 a shown in FIG. 7D , these holes are situated in two linear type of arrays, parallel to each other, creating two sets of hole pairs. Either a clockwise arc trajectory 620 or a counterclockwise arc trajectory 622 (depicted in FIGS. 6A and 6B ) are attainable via selecting the proper hole pair for support bracket 730 mounting. The pivoting storage apparatus 716 is attached to one set of mounting holes (i.e. clockwise mounting holes 726 or counterclockwise mounting holes 726 ) using an appropriate fastening means (e.g. screws, nuts & bolts, rivets, locking pin hardware, snap-fit, and the like). To preserve the ability to select the aforementioned mounting options, selecting removeably attachable fasteners (e.g. screws, nuts & bolts, etc.) is preferable over fastening means not intended for disassembly (e.g. rivets, adhesives, etc.).
[0180] FIGS. 8A to 8C show various views and aspects of another embodiment consisting of a pivoting storage apparatus 824 having a left rail 826 and opposing right rail 828 located on bottom 832 of rectangular base 830 , best depicted in FIG. 8C . Pivoting storage apparatus 824 left rail 826 and a right rail 828 are slidingly received by left slot 820 and right slot 822 horizontal supports respectively, or any other horizontal pair of receiving slots, providing height adjustment depicted in FIG. 8A . Left slot 820 and opposing right slot 822 are located on the right side wall 810 and left side wall 812 respectively, of interior 814 of storage structure 816 . Back wall 818 furnishes pivoting storage apparatus 824 a natural back stop when inserted into any pair of receiving slots.
[0181] The pivoting storage apparatus 824 sliding relationship with a corresponding slot pair provides a user positionable feature giving the user additional access to shelf contents when pivoting storage apparatus 824 , as a whole, is pulled forward. When the pivoting storage apparatus 824 is pulled forward, objects stored on the non-pivoting corner tray 114 as well as the objects resting on pivoting corner tray 114 become more accessible to the user; furthermore, accessibility to objects resting on corner tray 114 is further improved when corner tray 114 is situated in open position 634 (as depicted in FIG. 6B ) and pivoting storage apparatus 824 is concurrently set to the forward position.
[0182] FIG. 9A illustrates a standalone corner tray container 900 having a corner tray container bottom 904 , with a container bottom 906 that possesses a generally triangular bottom geometry that is substantially similar in both size and shape to integrated corner tray 114 a overall general shape, or perimeter geometry, so that corner tray container 900 provides a space efficient means for storage when resting upon integrated corner tray 114 a , or like corner tray versions. Corner tray container 900 system possesses optional corner tray container cover 902 having a plurality of optional corner tray container cover apertures 902 a ; apertures provide a venting means for deodorizers, baking soda, and the like.
[0183] FIG. 9B is a perspective illustration of corner tray container 900 system resting on integrated corner tray 114 a of the present invention depicting a space efficient means for storage. FIG. 9C is a top view of corner tray container 900 system resting on integrated corner tray 114 a further depicting a space efficient means for storage.
[0184] FIG. 9B further illustrates optional first main tray handle 910 and second main tray handle 912 . The function of both main tray handles is to provide a user an easily accessible feature to facilitate the deployment of main tray 914 . First main tray handle 910 and second main tray handle 912 are depicted as integrated tabs that are vertical extensions of first main tray edge 911 a and second main tray edge 911 b , respectively. The depictions of first main tray handle 910 and second main tray handle 912 are exemplary, and thus are not limited to the depicted embodiment.
[0185] Another embodiment of the present invention further includes a main tray utilizing a self-closing feature (not shown) where the main tray, in its open position, upon being released by the user, automatically returns to the home position. The apparatuses for accomplishing such self-closing features are well known and their relatively simple designs enable prompt understanding of the associated mechanical workings. An example of such a mechanism is based on the use of coil springs where energy is stored during the opening of the main tray (by the user) is used to wind the spring and returning the main tray back to its home position is powered by the unwinding spring. Another such example is a gravity based weight system where the opening of the main tray (by the user) is used to elevate a weight and returning the main tray back to its home position is powered by the weight, connected to the main tray (via a cable or the like), being pulled back downward by gravitational forces. Other examples of such self-closing features are based upon compression springs, leaf spring, electric motors, and the like.
[0186] The materials that comprise the bulk of the present invention are preferably those of relatively high strength and low weight. In the polymer family, moldable plastics such as Lexan, Nylon, ABS, and the like, can provide relatively high strength and low weight properties in addition to providing high production, low cost advantages. If necessary, additional material's strength can be accomplished through the use of plastic fillers (e.g. glass fiber, and the like); the amount of filler used depends upon the characteristics desired. Exemplary polymers or plastics containing filler include: 30% glass fiber filled nylon, 10% glass fiber filled ABS, or 30% glass fiber filled Lexan (polycarbonate, to name a few. The use of transparent or translucent plastics provides the user with additional benefits including improved illumination and object identification (hindered by opaque materials). From the metals family of materials, aluminum is an example of such a high strength and low weight material, although the use of heavier stainless steel may be preferred in commercial food service type environments.
[0187] Composites such as fiberglass are other options that can provide a desired aesthetic look and/or feel in addition to supplying preferred or target combination of engineering properties such as thermal expansion, weight, creep, UV resistance, etc. for specific users and/or environments. The fasteners, brackets, and tracks aforementioned in the present invention with all its embodiments can be fabricated from most any engineering material that can withstand the stresses and wear requirements including polymers, metals and composites, with metals such as surface finished steel, aluminum, and the like, are considered commonplace in such applications. | A pivoting storage apparatus that is adapted to storage structures such as cabinets, refrigerators, and the like, whose horizontal interior storage surfaces are generally rectangular. The shelving system is presented in the form of a shelf accessory, in addition to use as an independent storage platform. A portion of the rotary shelving is capable of being manually drawn out of the confines of the storage structure's interior by the user, thereby enabling easy access to shelf contents. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of Provisional Application U.S. Ser. No. 60/815,870, filed on Jun. 23, 2006 (and entitled Electronic Adapter For Electro-Active Spectacle Lenses That Enables Near Universal Frame Compatibility) which is incorporated in its entirety herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention generally relates to an adapter for a spectacle frame housing electro-active lenses. Specifically, this invention relates to an adapter configured for enabling a spectacle frame to operate and control electro-active tenses housed therein without the need to either uniquely design and manufacture the spectacle tame or to perform undue modifications of an existing spectacle frame. In particular, the spectacle frame may allow electro-active lenses housed therein to focus and be controlled both automatically and manually with heretofore unrealized results.
[0004] 2. Description of the Related Art
[0005] With the invention of electro-active spectacle lenses that provide dynamic changes in focus there is a desire to engineer these lenses such that they can be compatible with most, if not all, pre-existing spectacle frame designs. To accomplish such a task, all of the components required to operate the electro-active functionality must be incorporated either internally or externally to the body of the lens so that the lens can be mounted into any unmodified spectacle frame and still be both aesthetically acceptable and fully functional.
[0006] Historically, the optical industry has been structured in such a way that the patient selects his or her eyewear based largely on aesthetics that relate to frame comfort and appearance. Generally the frames are the first item selected in picking out prescription eyeware. Lenses, including tints, coatings, and optical design are usually picked second. Given the significant number of available frame styles, sizes, and colors, the manner in which the industry has historically functioned, and the desire of the consumer or patient to have a vast selection of frames to choose from, there is a desire to provide a means and system for near universal compatibility between the new electro-active lenses and existing frame designs.
[0007] Accordingly, there is now provided with this invention an improved spectacle frame adapted for housing electro-active lenses that effectively overcomes the aforementioned difficulties and longstanding problems inherent in the art. These problems have been solved in a simple, convenient, and highly effective way by which to control electro-active lenses.
SUMMARY OF THE INVENTION
[0008] According to one aspect of the invention, an adapter for an electro-active lens is disclosed, wherein the electro-active lens is housed in a spectacle frame and the electro-active lens has a first set of electrical contacts. The adapter is a separate element from the electro-active lens and has a second set of electrical contacts for providing an electrical signal to the electro-active lens through the first set of electrical contacts.
[0009] As will be appreciated by those persons skilled in the art, a major advantage provided by the present invention is enabling a spectacle frame to operate and control electro-active lenses housed therein without the need to either uniquely design and manufacture the spectacle frame or to perform undue modifications of an existing spectacle frame. The spectacle frame may allow electro-active lenses housed therein to focus and be controlled both automatically and manually with heretofore unrealized results. Additional objects of the present invention will become apparent from the following description.
[0010] The method and apparatus of the present invention will be better understood by reference to the following detailed discussion of specific embodiments and the attached figures which illustrate and exemplify such embodiments.
DESCRIPTION OF THE DRAWINGS
[0011] A specific embodiment of the present invention will be described with reference to the following drawings, wherein:
[0012] FIG. 1 is a diagrammatic representation of an example of an electro-active lens and its drive components.
[0013] FIG. 2A is a front view of a spectacle frame housing the adapter of the present invention.
[0014] FIG. 2B is a top view of a spectacle frame housing the adapter of the present invention.
[0015] FIG. 3A is a top view of the left temporal side of an embodiment of the electro-active spectacle lens of the present invention.
[0016] FIG. 3B is a top view of the top left temporal side of an embodiment of the adapter of the present invention.
[0017] FIG. 3C is a top view of the top left temporal side of another embodiment of the adapter of the present invention.
[0018] FIG. 3D is a top view of the top left temporal side of another embodiment of the adapter of the present invention.
[0019] FIG. 3E is a top view of the top left temporal side of another embodiment of the adapter of the present invention.
[0020] FIG. 3F is a top view of the top left temporal side of another embodiment of the adapter of the present invention.
[0021] FIG. 3G is a top view of the top left temporal side of another embodiment of the adapter of the present invention.
[0022] FIG. 3H is a top view of the top left temporal side of another embodiment of the adapter of the present invention.
[0023] FIG. 3I is a top view of the left temporal side of another embodiment of the electro-active spectacle lens of the present invention.
[0024] FIG. 3J is a top view of the top left temporal side of another embodiment of the adapter of the present invention.
[0025] FIG. 4 is a front view of an embodiment of the right side of the electro-active spectacle lens and adapter of the present invention.
[0026] FIG. 5 is a front view of another embodiment of the right side of the electro-active spectacle lens and adapter of the present invention.
[0027] FIG. 6 is a front view of another embodiment of the tight side of the electro-active spectacle lens and adapter of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0028] The following preferred embodiment as exemplified by the drawings is illustrative of the invention and is not intended to limit the invention as encompassed by the claims of this application.
[0029] As shown in FIG. 1 , as in all embodiments of the present invention, the electro-active spectacle lenses 100 contain an electro-active lens element 101 and drive electronics, including one or more focus sensors 102 , all of which are embedded within the body of a lens 103 that act to correct refractive errors of the eye not associated with presbyopia. The drive electronics are contained within a driver. The driver may also include all necessary control components for providing the appropriate electrical signal for providing the proper optical power in the electro-active lens. The body of the lens may be either a finished blank (two optical quality surfaces) or a semi-finished blank (one optical quality surface). The focus sensors, drive electronics, and electro-active lens element may be typically attached to the anterior and/or posterior surface of a flexible but transparent star shaped substrate 104 where electrical connection is made via thin film transparent electrical leads 105 (such as, by way of example only, indium tin oxide, ITO). These thin film transparent electrical leads include connections 106 for an electrical power source. These thin film transparent electrical leads may also include connections for digital or analog signal transfer. In certain other embodiments, the power source and signal connections may be of a different design where they are connected to the flexible substrate but contain non thin-film conductors, such as, by way of example only, fine gauge metal wire. This alternative design is such that the connection does not significantly interfere with the user's vision or the aesthetics of the lens. These power source and signal connections as well as the focus sensors and drive electronics are placed near the edge of the lens, near where the frame eye-wire and temple connect, such that when the lens is fitted within the frame, the power source, drive electronics, and focus sensors do not interfere with the vision of the user. Alternatively, the drive components may be placed distal from the electro-active lenses either in the spectacle frame, the temples, or in the adapter of the present invention.
[0030] In an embodiment of the invention shown in FIG. 2 , the electro-active lens 201 with electro-active region 203 is edged (cut to the shape of the spectacle frame) using techniques well known in the art. The process of edging the lens acts to either partially or fully expose the electrical leads that connect to the power source. This edged lens is then combined with an electrical adapter 202 that, as shown in FIG. 3B , may contain one or more electrical power sources 305 , one or more electrical switches to provide manual control of the lenses to the user 306 , and one or more sensors 307 that acts to detect the presence of the user (determine if spectacles are being worn). As an alternative design, the sensor 307 may also include the drive electronics 102 for the electro-active lens. The sensor 307 may also sense if the frame is opened. This adapter has electrical contacts 308 that correspond to the power source and signal electrical contacts in the lens 106 such that when the adapter is placed between the spectacle lens and the eye wire of the spectacle frame, the pressure associated with securing the lens within the frame acts to make positive electrical contact between the lens and the adapter as well as physically secure the adapter to the spectacles. Components within the adapter are connected electrically by means of internal wiring 309 . Power sources included within the adapter may be, by way of example only, disposable zinc-air batteries or rechargeable Li-ion or Li-polymer batteries. Manual switches included within the adapter may be, by way of example only, pressure switches, capacitive touch switches or optical proximity switches. Sensors to determine if the spectacles are being worn may be, by way of example only, optical proximity switches or accelerometers which, if activated, instruct the drive electronics to operate the focus sensors within the body of the lens. In this embodiment each of the lenses would be identical and would each require an individual adapter. The driver may provide an electrical signal for generating the appropriate amount of optical power in each of the electro-active lenses. The driver may also include a focusing sensor for determining the appropriate signal for the electro-active lenses.
[0031] As also shown in FIGS. 3A-3J , the use of such an adapter 202 may require, in certain embodiments, other machining steps in addition to edging where, by way of example only, one or more of a slot, groove, or notch 301 is machined into the body of the lens 201 such that robust physical and electrical connection is made between the frame, lens, and adapter. As the adapter would be placed near to where the frame eye-wire and temple connect, such a machining step may allow the adapter to be located on the posterior surface of the lens 302 and be mostly hidden from view by the temple hinge. Such a placement would be advantageous for preserving the aesthetic quality of the spectacles. It is preferable that the edge profile of the adapter 303 match that of the lens 304 such that a secure fit is guaranteed between the frame, lens, and adapter.
[0032] Embodiments of the adapter of the present invention may contain any of a combination of components. For example, as shown in FIG. 3B , the adapter may have an on/off switch, a power source, and a sensor for sensing the presence of the user. Alternatively, as shown in FIG. 3C , the adapter may only have a power source. Alternatively, as shown in FIG. 3D , the adapter may only have an on/off switch. Alternatively, as shown in FIG. 3E , the adapter may only have a sensor for sensing the presence of the user. As shown in FIG. 3F , the adapter may have an on/off switch, and a sensor for sensing the presence of the user. As shown in FIG. 3G , the adapter may have an on/off switch, and a power source. As shown in FIG. 3H , the adapter may have a power source and a sensor for sensing the presence of the user.
[0033] As further illustrated in FIGS. 3I and 3J , the electrical connection made between the frame, lens, and adapter may include a physical connection in which mating elements between the lens and the adapter are screwed to one another. As shown, the adapter may include screw threads 311 which secure into mating threads 310 in the lens. Of course, as is well known in the art, such physical connections can further include a wide variety of equivalents, for example, a bayonet-type connection, a detent, snap-like connection and etc. As is also well known in the art, the electrical connection may be made with a wide variety of electrical mating elements, for example, male/female connectors, plugs, sockets, pins, and the like.
[0034] The adapter may be positioned so that it simultaneously contacts the lens and the frame or, alternatively, it may be positioned so that it only contacts the lens and does not contact the frame. The adapter may be positioned so that it is located under and above the surface of the lens when it is in contact therewith. The adapter may be further positioned so that it is located near a periphery of the surface of the lens when it is in contact therewith.
[0035] One issue with the above embodiments is that each lens operates independently from the other. Therefore, the possibility exists that under certain operational conditions one lens may be triggered to operate while the other is not. To eliminate this problem a means for synchronizing the operation of the two lenses must be devised such that when one of the two lenses is activated, the other will be activated by default. In another embodiment of the invention the electrical adapters of the two lenses are connected by means of discrete signal conduit such as, by way of example only, one or more of a small gauge metal wire or optical fiber. Such signal conduits could be hidden in the gap between the frame eye wire and the lens as well as behind the bridge that, joins the two lenses.
[0036] In another embodiment the two lenses are synchronized by means of a wireless optical connection designed to transmit data across the bridge as shown in FIG. 4 . In this embodiment an infrared optical transceiver unit 401 is tethered to each adapter 202 by means of a flex circuit 402 , which may be hidden between the superior eye-wire of the frame and the edged electro-active spectacle lens 201 . The transceiver unit is preferred to be located at the location of where the superior vertical distance of each eye-wire allows for the best, unhindered optical communication between the IR transceivers. As with the adapter, an additional machining step may be required where, by way of example only, one or more of a slot, groove, or notch 403 is machined into the body of the lens such that a robust physical connection is made between the transceiver unit and the spectacles. Furthermore, such machining steps would allow the transceiver unit to be mounted to either the anterior or posterior surface of the lens.
[0037] In another embodiment the two lenses are synchronized by means of a wireless, radio frequency (RF) communication system as shown in FIG. 5 . In this embodiment the electrical adapter 202 contains circuitry for an RF transceiver that is tethered to a flex circuit antenna 501 (for example only). This flex circuit antenna may be hidden between the frame eye wire and the edged spectacle lens 201 .
[0038] In another embodiment the two lenses are synchronized by means of inductive coupling as shown in FIG. 6 . In this embodiment the electrical adapter 202 contains circuitry for a pulsed current source that is tethered to multiple-turn coils of an electrical conductor made using flex circuit 601 (for example only). These flex circuit coils may be hidden between the frame eye wire and the edged spectacle lens. In this approach, current pulses in the coils of lens 1 generates a magnetic field which, by way of Faraday's law of induction, generates a current in the coils of lens 2 , which is then be detected by the circuitry of the electrical adapter of lens 2 . In this manner communication between the two lenses is enabled.
[0039] In another embodiment, the two lenses may be synchronized by means of ultrasonic signals transmitted over free space. In this embodiment the electrical adapter contains circuitry for an ultrasonic transceiver. Such an approach is advantageous in that no additional components are required to be tethered to the electrical adapter.
[0040] In yet another embodiment, the two lenses may be synchronized by means of vibrations transmitted through the spectacle frame. In this embodiment the electrical adapter contains a vibration transducer and detector that makes physical contact to the frame when the lenses, adapters, and frames are assembled. Transducers and detectors of vibrations may be made from, by way of example only, piezoelectric materials. Such an approach is advantageous in that no additional components are required to be tethered to the electrical adapter.
[0041] In order to simplify any of the above embodiments, only one lens could be outfitted with one or more focus sensors and a synchronization transmitter while the other lens would not include any focus sensors and only a synchronization receiver. In such an embodiment the lens with the focus sensor(s) would operate as the “master” while the other lens would operate as the “slave” and only operate when directed by the master. Such a one-way communication system would reduce power consumption (by eliminating synchronization transmitters and a focus sensors) and simplify synchronization, but at the expense of eliminating redundancy in the focus sensors.
[0042] Although the particular embodiments shown and described above will prove to be useful in many applications in the spectacle art and the electro-active lens art to which the present invention pertains, further modifications of the present invention will occur to persons skilled in the art. All such modifications are deemed to be within the scope and spirit of the present invention as defined by the appended claims. | An adapter for a spectacle frame is disclosed which is configured for enabling the spectacle frame to operate and control electro-active lenses housed therein. In particular, the spectacle frame may allow electro-active lenses housed therein to focus and be controlled both automatically and manually with heretofore unrealized results. | 1 |
FIELD OF THE INVENTION
The present invention relates to flash spinning of fiber forming polymers and in particular to the electrostatic charge applying system within a flash spinning apparatus.
BACKGROUND OF THE INVENTION
As noted in other patents and patent applications assigned to the assignee of the present invention, E. I. du Pont de Nemours and Company (DuPont), CFC solvents are presently used to manufacture flash-spun polyolefins such as Tyvek® spunbonded polyolefin. Tyvek® is a registered trademark of DuPont. However, CFC's are believed to have harmful environmental effects such as ozone depletion and are thus to be eliminated from conventional use. Plans are very much underway to continue making Tyvek® spunbonded olefin using a non-CFC solvent. However, the system using the new solvent tends to use higher charging currents and produces product at much lower throughputs as compared to the current system. Both the lower throughput and higher charging current tend to create more polymer dust during spinning. Thus, the electrostatically charged parts tend to become coated with dust and ultimately interferes with the efficient operation of the charging system, the uniformity of the charging, and the quality of the nonwoven sheet.
The electrostatic charging system basically comprises a DC voltage source, a wand or ion gun, and a conductive target plate connected to a suitable ground and spaced from the wand. A corona field is created between the wand and the target plate by the DC voltage source and the web is directed through the corona field to pick up charged particles that are migrating from the wand to the target plate. The wand basically comprises a plurality of needles, spaced along an arc, all of which are directed towards the target plate.
As the fiber is spun into the a continuous plexifilamentary film-fibril web, some of the polymer forms a fine dust that may float around the spin cell and collect on the components therein. Some of the dust also acquires a charge and therefore becomes attracted to and collects on both the needles and the target plate. Accumulation of polymer dust on the elements of the electrostatic charging system increases the resistance (since the polymer is not very conductive) resulting in higher energy requirements to maintain a sufficient charge on the web. As such, dust tends to foul the electrostatic charging system increasing energy requirements to continue to provide a suitable charge on the web. Eventually, electrostatic fouling will cause energy requirements to exceed predetermined current levels causing the pack to be shut down for replacement.
Spin packs are commonly shutdown and replaced for a variety of reasons. DuPont closely monitors pack life and pack mortality (why the pack had to be removed from service) because of its effect on the sheet quality and the profitability of the business. As noted above, high energy requirements and electrostatic fouling are common causes of pack failure. Based on tests using pentane hydrocarbon as a solvent, it is anticipated that more dust will be generated in the spin cell and that higher charging currents will be required to obtain as suitable charge on the web. Thus, it will be very likely that pack life will become almost entirely dependent on the operational life of the electrostatic system. As discussed in other patents and applications, pack life for spinpacks in the manufacture of Tyvek® spunbonded olefin will have a substantial effect on the profitability of the business.
Accordingly, it is an object of the present invention to provide a system which avoids the drawbacks as described above.
It is a more particular object of the present invention to provide a system which reduces the tendency of polymer or other debris from collecting on the wand or ion gun needles that will interfere with the operation of the charging system.
SUMMARY OF THE INVENTION
The above and other objects of the present invention are accomplished by the provision of a cleaning system which provides a gaseous flow over the needles of the wand to direct dust and debris in the spin cell from collecting on the needles of the wand.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may be better understood by reference to drawings of a preferred embodiment thereof. Accordingly, drawings of the preferred embodiment have been included herewith wherein:
FIG. 1 is a fragmentary cross sectional view of a conventional spinpack particularly illustrating the conventional form of the wand;
FIG. 2 is a fragmentary cross sectional view of the preferred embodiment of the diffuser wherein the wand is provided with the cleaning arrangement; and
FIG. 3 is a fragmentary front view of the wand and diffuser shown in FIG. 2 as indicated by the arrow 3 in FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now to the drawings, the invention will be described in relation to the wand as is currently configured and presently in use. The current configuration is shown in FIG. 1. The overall system is described in detail in other patents such as Blades et al (U.S. Pat. No. 3,227,784) and Brethauer et al (U.S. Pat. No. 3,851,023) which are incorporated herein by reference. Briefly, a spinpack generally indicated by the number 10, receives a polymer solution (polymer and solvent dissolved together) through a conduit 15 at elevated temperature and pressure. The polymer passes into a letdown chamber 17 near the spin orifice 18 to allow the spin mixture to drop to a slightly lower temperature prior to passing through the spin orifice 18. Upon passing through the spin orifice 18, the polymer solution enters the spin cell which has a much lower pressure and temperature.
As the polymer solution enters the spin cell environment, the solvent flashes and the polymer forms a plexifilamentary film-fibril strand S moving at very high speed. The strand S is directed to a baffle 23 where it is flattened and turned down toward a conveyor belt (not shown). The baffle also causes the flattened strand (now generally called a web W) to oscillate back and forth to lay it out across the conveyor belt (not shown) and form a batt suitable for pressing into a nonwoven sheet.
The path of the oscillating web W is between two spaced apart shields 30 and 35. A first shield 30 includes a recess 31 along an arc at its upper portion thereof. A wand 40 is mounted therein which includes a plurality of needles 42. Across the path of the web W from the wand 40 is a conductive target plate 50. The needles 42 are arranged to extend toward the target plate 50 such that the distal ends of the needles 42 do not quite project out from the recess 31.
In operation, the wand 40 and the target plate 50 are provided with a suitable DC charge and electric ground so that charged particles, i.e. electrons, ions or molecules, are formed on the tips of the needles 42 and move toward the target plate 50. The area of concentration of charged particles moving to the target plate is the corona field 48 which is generally indicated by the dashed lines extending from the needle 42 to the target plate 50. As the charged particles move toward the target plate 50 some of the particles are collected onto the web W and carried therewith to the conveyor belt. The resulting charge on the web W helps to maintain the plexifilaments in an open, spaced apart arrangement and also helps pin the web W down to the conveyor belt.
As described above, dust is formed in the spin cell by polymer debris that did not form into the continuous strand S. In the present arrangement, the needles 42 are open to any dust which gets between the shields 30 and 35. In FIGS. 2 and 3, there is illustrated a preferred embodiment of the present invention which provides greater resistance to having dust and debris collecting on the needles. In FIGS. 2 and 3, equipment that is essentially the same as in FIG. 1 has been identified with a similar number except that it is now a three digit number with the first digit being 1. For example, the first shield is number 30 in FIG. 1 and 130 in FIG. 2. That being understood, the description of the invention will continue.
In the present invention, the needles 142 are attached to a generally flat, arc shaped mounting bracket 145 such that the needles are generally normal to the plane of the flat bracket 145. The front shield 130 has a recess 132, but it faces away from the path of the web W rather than facing toward the path. The front shield 130 also includes a plurality of little holes 143 arranged to receive the distal end of each needle 142. It is preferred that the distal ends of the needles 142 protrude about 0.031±0.006 inches from the face of the front shield 130 into the path of the fiber. It is more preferable to have the distal ends of the needles protruding 0.031±0.003 inches from the face of the front shield 130. The holes 143 are also sized to have a diameter slightly larger than the diameter of each needle 142. In the preferred embodiment, the needle is 0.058 inches in diameter (not including the portion that tapers down at the end) and the hole is 0.094 inches in diameter.
The mounting bracket 145 is attached by suitable means such as bolts 146 to close the recess 132 and thereby essentially reform the recess into a plenum chamber within the shield 130. The resulting plenum chamber 132 is connected by a conduit 133 (best seen in FIG. 3) and other suitable means, such as a hose, etc. (not shown), to a suitable source of vaporized solvent. It should be noted that any gaseous fluid that is compatible with the solvent and the spin cell environment may be provided to the plenum chamber 132 to use in the inventive arrangement. As the gaseous fluid, preferably vaporized solvent, is provided into the conduit 133, it fills the plenum chamber 132 and passes out through the holes 143.
As may have been alluded to above, the holes 143 form annular passages around the needles 142 that substantially circumscribe each needle. As such, a stream of vaporized solvent moves along the length of each of the needles 142 to sweep any dust or polymer therefrom and to resist the momentum of any dust from entering the holes 143. The flow of vaporized fluid is dedicated to the task of sweeping away dust and debris and need not be very substantial as it is desirable not to change the aerodynamics of the flow of gases between the shields that accompany the web W. Typically, the flow of vaporized solvent around each needle is 0.75 scfm for a 10 needle array. This can be compared to a flow of about 260 scfm between the shields from all sources. Also, since the flow of vaporized solvent through the holes 143 is intended to be continuous, it is expected to be suitable to deflect and disperse dust or debris before it can contact the needles 142 or become firmly attached thereto. Preferably, the dust and debris is deflected into the more substantial vapor flow accompanying the web W to be carried along therewith and carried away on the forming sheet on the conveyor belt. As such the dust and debris would then be away from the electrostatic charging system and may be captured by suitable filters or other atmospheric control equipment in the spin cell, e.g. netting arrayed in the upper portion of the spin cell.
In a second preferred embodiment which is not shown, a second arc of needles is provided which is generally concentric with the first. The second row or arc of needles would include a second plenum chamber but be essentially the same as the first as shown in FIGS. 2 and 3. By the second preferred embodiment, the web W passes through a second corona field and will have a satisfactory charge applied thereto. Clearly other mechanical variations of this invention can be foreseen.
The foregoing description is provided solely to explain the details of the invention and the preferred embodiment. The scope or range of equivalents shall not be diminished by the description. For a clear definition of the scope of protection provided by the patent laws, please refer to the claims that follow. | This invention relates to a method and apparatus for sweeping dust and debris from the needles of a wand which is for applying an electrostatic charge to a plexifilamentary film-fibril web. The needles of the wand tend to acquire dust and debris from the polymer and by the present invention the dust and debris are efficiently swept away by a gaseous fluid flow over the needles preferably so that the fluid passes circumferentially over the needles through an annular passage. | 3 |
RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 12/268,987 filed Nov. 11, 2008.
U.S. patent application Ser. No. 12/268,987 is a continuation of U.S. patent application Ser. No. 11/888,553 filed Jul. 31, 2007, now U.S. Pat. No. 7,448,599 which issued on Nov. 11, 2008.
U.S. patent application Ser. No. 11/888,553 is a continuation of U.S. patent application Ser. No. 11/410,736 filed Apr. 25, 2006, now U.S. Pat. No. 7,249,755 which issued on Jul. 31, 2007.
U.S. patent application Ser. No. 11/410,736 is a continuation of U.S. patent application Ser. No. 11/087,483 filed Mar. 22, 2005, now U.S. Pat. No. 7,032,892, which issued on Apr. 25, 2006.
U.S. patent application Ser. No. 11/087,483 is a continuation of U.S. patent application Ser. No. 10/456,247 filed Jun. 5, 2003, now U.S. Pat. No. 6,896,244, which issued on May 24, 2005.
U.S. patent application Ser. No. 10/456,247 is a continuation of U.S. patent application Ser. No. 09/976,380 filed on Oct. 11, 2001, now abandoned.
U.S. patent application Ser. No. 09/976,380 is a continuation-in-part of U.S. Design patent application Ser. No. 29/067,042 filed on Feb. 27, 1997, now U.S. Pat. No. D520,349, which issued on May 9, 2006.
U.S. Design patent application Ser. No. 29/067,042 claims priority of Canadian Industrial Design Application No. 1996-2618 filed on Nov. 26, 1996, now Canadian Industrial Design Registration No. 83049, which registered on Feb. 6, 1998.
The subject matter of the foregoing related applications are incorporated herein by reference.
TECHNICAL FIELD
The present invention relates to hardware for use in the construction of gates and, more specifically, to gate hardware adapted to brace the vertical and horizontal support members of a wooden gate and rotatably connect these members to a fixed structural member.
BACKGROUND OF THE INVENTION
Gates are often used to allow selective access through a wall or fence. Conventionally, gates are constructed as follows. Two vertical support members and two horizontal support members are fastened together in a rectangular shape to form what will be referred to herein as a gate box. Fence boards or the like are fastened to the support members, and one of the vertical support members is rotatably attached by two or more hinge assemblies to a structural member such as a wall or post.
Using conventional gate building techniques, fasteners such as nails or screws are driven through one support member into another support member to form the corners of the gate box. Over time, the force of gravity and wood shrinkage will cause these fasteners to loosen, allowing the gate box to sag out of its desired rectangular shape.
Accordingly, metal L-brackets, wooden brace members, triangular pieces of plywood, and the like are often fastened to the adjacent ends of the support members to strengthen the inside corners of the gate box. In other situations, a wire is placed in tension between the upper proximal and lower distal corners of the gate box to support the lower distal corner of the gate box and thereby reduce sagging of the gate. Such bracing techniques are somewhat effective but also commonly employ fasteners that are susceptible to failure and can be relatively time consuming to implement.
Another problem with conventional gate building techniques is that fasteners such as nails or screws are similarly used to attach the hinge assemblies to the vertical support member adjacent to the structural member. The loads are transferred to the gate through the screws placed in tension. As the wood shrinks and the gate is opened and closed, the fasteners under tension tend to loosen and may eventually fail.
As the hinge fasteners loosen, the entire gate assembly may sag relative to the hinge assemblies and thus the structural member, even if the gate box maintains its rectangular shape. The use of braces at the corners of the gate box will worsen sagging at the hinges because the materials and hardware used for bracing increase the weight of the gate; this increased weight increases the forces of gravity on the fasteners used to attach the hinge assemblies to the proximal vertical support member.
The Applicant is aware of a product sold in Canada as early as approximately 1993 under the tradename “Artistic Steel Gate Frames”. The Artistic Steel Gate Frame product comprises distal and proximal brace members, with hinges being attached to the proximal brace member. A gate assembly constructed using the Artistic product would use upper and lower horizontal wooden support members, but would not use vertical support members. Instead, the distal and proximal brace members would form the structure of the vertical sides of the gate. Accordingly, the brace members of the Artistic product were sold in a plurality of sizes, with each size corresponding to a given distance between the upper and lower horizontal support members.
One problem with the Artistic product is that this system requires the manufacturer to produce and keep in inventory, and the retailer to stock, multiple sizes of brace members.
In addition, the end user is limited to one of these multiple sizes of brace members; one could not create a gate assembly having a custom distance between the upper and lower horizontal support members.
From the foregoing, it should be clear that one object of the present invention is to create bracket systems and methods that are strong, that are easy and inexpensive to use, and which allow significant flexibility in the final design of the gate assembly.
SUMMARY OF THE INVENTION
The present invention is a bracket system or method for forming gate assemblies. The bracket system comprises at least two brace members that are rigidly attached to hinge assemblies. The brace members are adapted to be attached to support members to form two corners of a gate box functioning as the structural portion of the gate assembly. The hinge assemblies are adapted to be rigidly attached to a fence post to allow the gate assembly to pivot relative to the fence post. Gate assemblies of arbitrary height and width can be formed using the bracket system of the present invention
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a gate frame system of the present invention comprising distal brace members and proximal brace assemblies;
FIG. 2 is an exploded, front elevation view of a gate assembly incorporating the gate frame system of FIG. 1 ;
FIG. 3 is a partial cut-away, front elevation view of the gate assembly of FIG. 2 attached to a fence post;
FIG. 4 is a front elevation view of the distal brace member depicted in FIG. 1 ;
FIG. 5 is a side elevation view of the distal brace member depicted in FIG. 1 ;
FIG. 6 is a bottom plan view of the distal brace member depicted in FIG. 1 ;
FIG. 7 is a top plan view of the distal brace member depicted in FIG. 1 ;
FIG. 8 is a front elevation view of the proximal brace member depicted in FIG. 1 ;
FIG. 9 is a side elevation view of the proximal brace member depicted in FIG. 1 ;
FIG. 10 is a bottom plan view of the proximal brace member depicted in FIG. 1 ; and
FIG. 11 is a top plan view of the proximal brace member depicted in FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
Referring initially to FIG. 1 , depicted therein is a gate bracket system 20 constructed in accordance with, and embodying, the principles of the present invention. Referring for a moment to FIGS. 2 and 3 , the gate bracket system 20 is adapted to form a gate box 22 to be used as part of a gate assembly 24 ; the gate assembly 24 is in turn to be connected to a structural member such as a fence post 26 ( FIG. 3 ) of a larger structure such as a fence 28 .
The exemplary gate assembly 24 comprises in addition to the bracket system 20 distal and proximal vertical support members 30 and 32 , upper and lower horizontal support members 34 and 36 , and a plurality of fence members 40 . The exemplary support members 30 - 36 are conventional wooden two-by-fours, but other materials and sizes may be used as the support members 30 - 36 . The exemplary fence members 40 are also conventionally made out of wood, but other materials and various sizes of any type of material may be used to form the fence members 40 .
The support members 30 - 36 and fence members 40 do not form a part of the present invention. A description of the construction and operation of these members 30 - 40 is not necessary to describe how to make and use the present invention and is included herein simply to illustrate the environment in which the present invention operates.
The fence post 26 is conventionally a wooden four-by-four, but other materials and sizes may be used to form the structural member to which the gate assembly 24 is rotatably attached. For example, rather than a fence post 26 , the structural member may be a wall of a structure. The fence post 26 and fence 28 also are or may be conventional and are not part of the present invention. As with the support and fence members 30 - 40 introduced above, a description of the construction and operation of the post 26 and fence 28 is not necessary to describe how to make and use the present invention. The fence post 26 and fence 28 are described herein simply to illustrate the environment in which the present invention operates.
The gate bracket system 20 of the present invention comprises first and second distal brace members 50 and 52 and first and second brace assemblies 54 and 56 . The first brace assembly 54 in turn comprises a first proximal brace member 60 and a first hinge assembly 62 , while the second brace assembly comprises a second proximal brace member 64 and a second hinge assembly 66 .
The exemplary brace members 50 , 52 , 60 , and 64 each comprise a horizontal portion 70 , a vertical portion 72 , and a brace portion 74 . An outer end 72 a of the vertical portions 72 is rigidly connected to an attachment region 70 a of the horizontal portions 70 . The exemplary brace portion 74 is preferably rigidly connected at an angle between bracing regions 70 b and 72 b of the horizontal and vertical portions 70 and 72 , respectively.
The choice of materials and shapes of the materials are not essential to any particular implementation of the present invention. The primary requirements of the brace members 50 , 52 , 60 , and 64 are that these members each define a horizontal support surface 80 and a vertical support surface 82 such that these surfaces rigidly extend from each other at a right angle. In the exemplary system 20 , the horizontal support surfaces 80 are formed on the horizontal portions 70 and the vertical support surfaces 82 are formed on the vertical portions 72 .
A plurality of fastener holes 90 are formed in the brace members 50 , 52 , 60 , and 64 ; the fastener holes 90 are adapted to allow fasteners 92 to attach, in a conventional manner, the brace members 50 , 52 , 60 , and 64 to the support members 30 - 36 . The fasteners 92 are preferably self-tapping screws but can be nails, bolts, or the like. The fasteners 92 are not part of the gate bracket system 20 of the present invention per se but, as will be described in further detail below, are used to combine the bracket system 20 with the support members 30 - 36 to form the gate assembly 24 .
The exact number and location of the fastener holes 90 is not critical to any given implementation of the present invention. In a broadest form of the bracket system 20 , the fastener holes 90 can be formed anywhere along the horizontal portions 70 and vertical portions 72 . The only requirement for the number and spacing of these holes is that the fasteners 92 extend through these holes 90 and into the support members to rigidly secure the brace members to the support members.
Given the foregoing general understanding of the present invention, the distal bracket members 50 and 52 and the proximal bracket assemblies 54 and 56 of the present invention will now be described in further detail with reference to FIGS. 4-11 .
The attachment and bracing regions 70 a and 70 b of the horizontal portions 70 of the exemplary bracket members 50 , 52 , 60 , and 64 are formed located generally as follows.
The horizontal portions 70 have an outer end 70 c and an inner end 70 d . The exemplary attachment regions 70 a are located between approximately 15-30%, and preferably approximately 20%, of the distance between the horizontal portion ends 70 c and 70 d as measured from the outer ends 70 c . The bracing regions 70 b are located between approximately 80-95%, and preferably approximately 88%, of the distance between the horizontal portion ends 70 c and 70 d as measured from the outer ends 70 c.
The horizontal portions 70 further define spacing regions 70 e (between the attachment regions 70 a and the outer ends 70 c ), inner regions 70 f (between the bracing regions 70 b and the inner ends 70 d ), and intermediate regions 70 g (between the attachment regions 70 a and the bracing regions 70 b ).
The length of the spacing regions 70 e is determined such that the vertical support members 34 and 36 fit snugly between the vertical portions 72 and the outer ends 70 c . In the case of the proximal bracket assemblies 54 and 56 , the length of the spacing regions 70 e allows the vertical support members 34 and 36 to fit snugly between the vertical portions 72 of the third and fourth bracket members 60 and 64 and the first and second hinge assemblies 62 and 66 , respectively. When, as is typical, two-by-four dimensional lumber is used to form the vertical support members, the length of the spacing regions 70 e will be approximately 3½″, or slightly greater to allow for variations in the true dimensions of the lumber.
The vertical portions 72 each comprise the outer ends 72 a discussed above and an inner end 72 c . The bracing regions 72 b are located approximately 85% of the distance between the horizontal portion ends 72 a and 72 c as measured from the outer ends 72 a . The vertical portions 72 thus each define a main region 72 d between the outer end 72 a and the bracing region 72 b and an inner end region 72 e between the bracing region 72 b and the inner end 72 c.
In the horizontal portions 70 of the exemplary brace members 50 , 52 , 60 , and 64 , first, second, and third fastener holes 90 a , 90 b , and 90 c are formed in the spacing regions 70 e , inner regions 70 f , and intermediate regions 70 g , respectively. The first, second, and third fastener holes are spaced approximately 15%, 46%, and 96%, respectively, of the distance between the horizontal portion ends 70 c and 70 d as measured from the outer ends 70 c.
In the vertical portions 72 of the exemplary brace members 50 , 52 , 60 , and 64 , fourth and fifth fastener holes 90 d and 90 e are formed in the main region 72 d and a sixth fastener hole 90 f is formed in the inner end region 72 e . The fourth, fifth, and sixth fastener holes 90 d , 90 e , and 90 f are spaced approximately 15%, 46%, and 96% of the distance between the horizontal portion ends 72 a and 72 c as measured from the outer ends 72 a.
The fastener holes 90 of the exemplary brace members 50 , 52 , 60 , and 64 are formed along a horizontal center line A of the horizontal portion 70 and a vertical center line B of the vertical portion 72 .
The exemplary horizontal and vertical portions 70 and 72 are made of flat pieces of rigid metal, but other relatively rigid materials and shapes that function in a similar manner may be used. For ease of manufacturing, the exemplary horizontal and vertical portions 70 and 72 are identical in length, and the fastener holes 90 are formed at identical locations therein; only one part thus needs to be fabricated and stocked to form the exemplary brace members 50 , 52 , 60 , and 64 .
The brace portion 74 is typically round or flat metal stock, but other shapes and materials may be used. For example, the brace portion 74 may be a triangular web of flat material that extends between the horizontal and vertical portions 70 and 72 . In this case, the entire brace member may be cast of metal or injection molded from plastic. If a triangular web or similar brace portion is used, it may be necessary to form the fastener holes 90 such that they are offset from the horizontal and vertical centerlines A and B.
From the foregoing, it should be clear that the exemplary brace members 50 , 52 , 60 , and 64 are identical, which is preferred for manufacturing purposes. However, these brace members 50 , 52 , 60 , and 64 need not be identical to practice the present invention in its broadest form.
The first and second hinge assemblies 54 and 56 are or may be conventional and will be described herein only to the extent necessary for a complete understanding of the present invention.
As is conventional, the hinge assemblies 54 and 56 each comprise a gate plate 120 and a post plate 122 . These plates define hinge projections 124 that receive a hinge pin (not shown). The hinge pin allows the gate and post plates 120 and 122 to rotate relative to each other about a hinge axes C and D defined by the hinge assemblies 54 and 56 .
The outer ends 70 c of the horizontal portions 70 of the first and second brace members 60 and 64 are rigidly connected to the gate plates 120 . In particular, the horizontal center lines A of the horizontal portions 70 of these brace members 60 and 64 are tangential to circles centered about the hinge axes C and D, respectively. The vertical center lines B of the vertical portions of the brace members 60 and 64 are parallel to the hinge axes C and D, respectively.
An array of fastener holes 90 is formed in the post plate 122 to allow this plate to be rigidly attached to the fence post 26 . Preferably four fastener holes 90 are formed in the post plate 122 . The drawing depicts fastener holes 90 in the gate plate 120 ; these holes 90 in the plate 120 need not be used, but will be present if off-the-shelf hinge assemblies 62 and 66 are used.
The process of combining the bracket system 20 with the support members 30 - 36 to form the gate box 22 will now be described with reference to FIG. 2 .
Initially, as is conventional, the support members 30 - 36 are cut to the desired lengths. The length vertical support members 30 and 32 generally correspond to the height of the gate assembly 24 , while the length of the horizontal support members 34 and 36 closely correspond to the width of the gate assembly 24 . The minimum lengths of the support members 30 - 36 are determined by the horizontal portions 70 and vertical portions 72 of the brace members 50 , 52 , 60 , and 64 ; in particular, the support members 30 - 36 must be at least twice as long as the lengths of the horizontal and vertical portions 70 and 72 to prevent overlapping of the horizontal portions 70 or vertical portions 72 of adjacent brace members.
The first and second distal brace members 50 and 52 and first and second brace assemblies 54 and 56 are arranged such that: (a) horizontal and vertical support surfaces 80 a and 82 a of the first distal brace member 50 define first and second support surfaces of the bracket system 20 ; (b) horizontal and vertical support surfaces 80 b and 82 b of the second distal brace member 50 define third and fourth support surfaces of the bracket system 20 ; (c) horizontal and vertical support surfaces 80 c and 82 c of the first proximal brace member 60 define third and fourth support surfaces of the bracket system 20 ; and (d) horizontal and vertical support surfaces 80 d and 82 d of the second proximal brace member 54 define third and fourth support surfaces of the bracket system 20 .
The fasteners 92 are then inserted through the fastener holes 90 of the brace members 50 , 52 , 60 , and 64 and into the support members 30 - 36 to form the gate box 22 . In particular, fasteners 92 are driven through the holes 90 and into the support members 30 - 36 such that: (a) the upper horizontal support member 30 is drawn tight against the first and fifth support surfaces defined by the first distal brace member 50 and second proximal brace member 60 ; (b) the lower horizontal support member 32 is drawn tight against the second and sixth support surfaces defined by the second distal brace member 52 and fourth proximal brace member 64 ; (c) the distal vertical support member 34 is drawn tight against the third and fourth support surfaces defined by the first and second distal brace members 50 and 52 ; and (d) the proximal vertical support member 36 is drawn tight against the seventh and eight support surfaces defined by the first and second proximal brace members 60 and 64 .
The exact order of the attachments described in the preceding paragraph is not critical to the present invention in its broadest form. However, with the brace members 50 , 52 , 60 , and 64 described herein, fasteners 92 are preferably driven through at least the first fastener holes 90 a formed in the spacing regions 70 e of the horizontal portions 70 before fasteners 92 are driven through the fastener fourth, fifth, or sixth fastener holes 90 d - e of the vertical portions 72 . Otherwise, the vertical support members 34 and 36 may block access to the first fastener holes 90 a . Preferably, fasteners 92 are driven through the first through third fastener holes 90 a - c before fasteners are driven through the fifth through sixth fastener holes 90 d - e.
With the gate box 22 formed as described above, the hinge axes C and D will be substantially aligned. The gate box 22 so formed may thus then be attached to the fence post 26 by fasteners 92 extending through the fastener holes 90 in the post plate 122 and into the post 26 . When the post plates 122 are rigidly connected to the post 26 , the gate box 22 pivots relative to the fence post 26 about the hinge axes C and D.
The gate assembly 24 may be formed before or after the gate box 22 is attached to the fence post 26 by attaching the fence members 40 to at least one, and preferably at least two, of the support members 30 - 36 of the gate box 22 .
Given the foregoing, it should be clear that the present invention may be embodied in forms other than those depicted and described herein. The scope of the present invention should thus be determined by the claims appended hereto and not the preceding detailed description of the preferred embodiment. | A bracket system for forming gate assemblies comprising at least two brace members that are rigidly attached to hinge assemblies. The brace members are adapted to be attached to support members to form two corners of a gate box functioning as the structural portion of the gate assembly. The hinge assemblies are adapted to be rigidly attached to a fence post to allow the gate assembly to pivot relative to the fence post. Gate assemblies of arbitrary height and width can be formed using the bracket system. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority to Provisional Application Ser. No. 60/419,992, filed on Oct. 21, 2002, which is hereby incorporated by reference in its entirety for all purposes.
BACKGROUND OF THE INVENTION
In certain offshore applications, keel guides are mounted to various vessels or platforms to guide risers extending to subsea locations. The keel guides restrain the upper end of the risers against lateral motion, thus preventing the risers from interfering with each other or with the vessel or platform. Generally, a keel guide comprises a cylindrical member or “can” which is attached to the hull of the vessel or platform with an appropriate bracket.
Risers are permitted to move vertically within the keel guide to compensate for motion of the vessel or platform. Each riser is equipped with a keel joint designed to ride within the keel guide. Generally, the keel joint comprises a pipe section of increased thickness to withstand the bending loads exerted on the joint by the keel guide. The keel joint may be provided with an outer wear sleeve along the portion of the joint which contacts the keel guide.
In many applications, a tieback connector is coupled to a lower end of the riser and moved to the seabed as the riser is lowered. However, such connectors may tend to be too large to pass through the keel guide of nominal size. Accordingly, the riser is run outside of or offset from the keel guide and moved into the keel guide in a later procedure. In some applications, for example, the keel guide is formed with a slot, and once the connector has passed the keel guide, the vessel or platform is translated toward the riser until the riser passes through the slot and into the keel guide. The riser is then moved vertically until the keel joint enters the keel guide. The outer diameter of the keel joint is larger than the width of the slot to restrain the keel joint within the keel guide.
In some applications, the riser is lowered until the tieback connector is below the keel guide. At this point, the vessel or platform is translated, until the riser moves through the slot in the keel guide. The riser is then lowered and positioned until the keel joint is within the keel guide, the riser is tensioned and the keel joint remains positioned in the keel guide.
Translation of the vessel or platform to the riser coupled with subsequent movement of the keel joint into the keel guide is a costly and time-consuming process. Additionally, such an approach typically requires the cutting of a slot into the platform structure of sufficient width to permit the passing of the riser from a position external to the keel guide to a position within the keel guide.
SUMMARY
The present invention relates generally to a technique for guiding a riser in an offshore environment. The technique utilizes a bushing assembly that may be selectively landed within a keel guide. The bushing assembly also comprises an opening sufficient to permit relative linear movement of the riser therethrough. The bushing assembly allows the use of a keel guide with a larger diameter, e.g. sufficient to permit the passing of a tieback connector, while still guiding linear movement of the riser within the keel guide.
BRIEF DESCRIPTION OF THE DRAWINGS
Certain exemplary embodiments of the invention will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and:
FIG. 1 is a front elevational view of a riser being installed in a keel guide, according to an embodiment of the present invention;
FIG. 2 is a top view of a keel guide, according to one embodiment of the present invention;
FIG. 3 is a cross-sectional view taken generally along line 3 — 3 of FIG. 2 ;
FIG. 4 is a partial cross-sectional view taken generally along line 4 — 4 of FIG. 2 ;
FIG. 5 illustrates one embodiment of a bushing being installed in a keel guide;
FIG. 6 is a cross-sectional view taken generally along line 6 — 6 of FIG. 5 ;
FIG. 7 is a top view of an embodiment utilizing several keel guides arranged on a hull;
FIG. 8 is a top view of another embodiment of a keel guide having retractable pins for retaining a bushing;
FIG. 9 is a side cross-sectional view taken generally along line 9 — 9 of FIG. 8 ;
FIG. 10 illustrates a guide bushing being installed in a keel guide as illustrated in FIG. 8 ;
FIG. 11 is a cross-sectional view of a plumb mounted lock-down pin assembly taken generally along line 11 — 11 of FIG. 9 ;
FIG. 12 is a cross-sectional view similar to FIG. 11 , but showing an obliquely mounted lock-down pin assembly;
FIG. 13 is a top view of a plurality of keel guides of the type illustrated in FIG. 8 , arranged on a hull;
FIG. 14 is a side cross-sectional view of another embodiment of a keel guide having spring-loaded retaining pins;
FIG. 15 is a side view of the guide bushing illustrated in FIG. 14 being installed in a keel guide;
FIG. 16 is an expanded view of a spring-loaded retaining pin illustrated in FIG. 15 ;
FIG. 17 is a side cross-sectional view of another embodiment of a bushing disposed within a keel guide;
FIG. 18 is a cross-sectional view taken generally along line 18 — 18 of FIG. 17 ;
FIG. 19 is a top view of another embodiment of a keel guide having a lock-down pin assembly;
FIG. 20 is a side cross-sectional view taken generally along line 20 — 20 of FIG. 19 ;
FIG. 21 is an expanded view of an embodiment of a lock-down pin assembly illustrated in FIG. 20 ;
FIG. 22 is a cross-sectional view taken generally along line 22 — 22 in FIG. 21 ;
FIG. 23 is a cross-sectional view taken generally along line 23 — 23 in FIG. 21 ;
FIG. 24 is a top view of an embodiment of a keel guide system having a band-type locking device;
FIG. 25 is a side partial cross-sectional view of the keel guide system illustrated in FIG. 24 ;
FIG. 26 is a cross-sectional view taken generally along line 26 — 26 of FIG. 25 ; and
FIG. 27 is a cross-sectional view taken generally along line 27 — 27 of FIG. 24 .
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Referring generally to FIG. 1 , an exemplary embodiment of a keel guide system 30 is illustrated. Keel guide system 30 comprises a keel guide 32 , a riser assembly 34 and a bushing 36 to be selectively landed in keel guide 32 . In at least one embodiment, riser assembly 34 comprises a keel joint 38 , and bushing 36 is temporarily coupled to riser assembly 34 at or below keel joint 38 . As riser assembly 34 is moved downwardly through keel guide 32 , bushing 36 lands in keel guide 32 and is released from riser assembly 34 to permit keel joint 38 to slide in a linear direction within an opening 39 formed axially through bushing 36 .
In the embodiment illustrated, keel guide system 30 also comprises a connector 40 , such as a tieback connector. Keel guide 32 is sized to permit the passage of connector 40 as riser assembly 34 is fed downwardly towards the subsea floor. Additionally, keel guide 32 may be attached to a structure 42 which, by way of example, comprises a hull of a vessel or a platform used in an offshore application. In various embodiments, the vessel or platform may include, but are not limited to, a spur platform or a tension leg platform (TLP). Keel guide 32 is attached to the vessel or platform via an appropriate bracket 44 .
One embodiment of keel guide system 30 is illustrated in FIG. 2 . In this embodiment, keel guide 32 is mounted to a vessel or platform by bracket 44 . An inner diameter 46 of keel guide 32 is sufficiently large to allow passage of tieback connector 40 or other component attached to the bottom of riser assembly 34 .
As illustrated, keel guide 32 comprises a side opening 48 that extends the longitudinal length of keel guide 32 . Side opening 48 allows keel guide 32 to be opened and closed a slight amount to increase or decrease the effective internal diameter 46 of keel guide 32 . A locking device 50 , such as a band-type locking device, is coupled to keel guide 32 to open or close the keel guide 32 .
One exemplary locking device 50 is illustrated in cross-section in FIG. 3 . In this embodiment, locking device 50 comprises a pivot bracket 52 attached to keel guide 32 by, for example, welding or other appropriate fastener, on one side of opening 48 . Pivot bracket 52 comprises a pair of slots 54 for receiving corresponding pins 56 extending from a pivot sleeve 58 .
A second bracket 60 is attached to keel guide 32 by welding or other appropriate fastener on a side of opening 48 opposite pivot bracket 52 . Second bracket 60 comprises a remote operated vehicle (“ROV”) bucket 62 . A stem 64 is coupled between pivot sleeve 58 and bucket 62 and extends across side opening 48 . Stem 64 may be threadably engaged with pivot sleeve 58 and retained against movement relative to ROV bucket 62 by a shoulder 66 and a retaining ring 68 . Stem 64 further comprises a head 70 that extends into ROV bucket 62 . Head 70 is adapted for engagement and rotation by an ROV manipulator to selectively increase or decrease the width of side opening 48 and thus the diameter 46 of keel guide 32 .
Referring generally to FIG. 4 , in this embodiment, bushing 36 comprises a wear bushing assembly 72 disposed in an annular space between keel guide 32 and keel joint 38 . Wear bushing assembly 72 has a bushing member 74 and a plurality of wear members 76 . Wear members 76 may be attached to bushing member 74 by fasteners, such as screws 78 and are oriented to bear against keel joint 38 , as illustrated. Thus, wear members 76 may be replaced due to, for example, sacrificial wear. In other embodiments, wear members 76 may comprise coatings or other types of hardened surfaces, e.g. hard facing, to reduce the detrimental effects of wear. The coating may be formed of a hardened metal or a nonmetallic material applied to bushing member 74 .
Bushing 36 is selectively received and held within keel guide 32 by a retention or landing mechanism 80 . An exemplary landing mechanism 80 comprises a landing feature 82 , e.g. a groove, defined by a lower shoulder 84 and an upper shoulder 86 . Bushing member 74 is received in landing feature 82 and is retained against axial movement by lower shoulder 84 and upper shoulder 86 .
To facilitate landing of bushing 36 in keel guide 32 , bushing 36 may be temporarily attached to riser assembly 34 by a mounting mechanism 88 as illustrated in FIG. 5 . One exemplary mounting mechanism 88 comprises a clamp connector 90 which connects wear bushing assembly 72 to riser assembly 34 generally at the junction between keel joint 38 and a next lower riser section 92 . A lower clamp 94 is secured below a flange 96 disposed on lower riser section 92 . An upper clamp 98 is secured above flange 96 on keel joint 38 . Lower clamp 94 is secured to upper clamp 98 by a plurality of tie rods 100 and corresponding fasteners, such as nuts 102 .
As illustrated in FIG. 6 , lower clamp 94 and upper clamp 98 may each comprise semicircular halves 104 and 106 that are secured around riser assembly 34 by one or more appropriate fasteners 108 , such as screws. Clamp connector 90 is secured to wear bushing assembly 72 by posts 110 . In the specific embodiment illustrated, posts 110 extend from wear bushing assembly 72 to upper clamp 98 and are secured to upper clamp 98 by shear pins 112 (see FIG. 5 ).
Prior to running riser assembly 34 , the locking device 50 on keel guide 32 is actuated via, for example, an ROV to open keel guide 32 to a position where the inner diameter 46 above landing feature 82 is slightly larger than the outside diameter of bushing 36 . The inside diameter below landing feature 82 remains slightly smaller that the outside diameter of bushing 36 . As bushing 36 is lowered into keel guide 32 , bushing assembly 72 lands on lower shoulder 84 . As the riser assembly 34 is further lowered, the weight of the riser assembly causes the shearing of shear pins 112 . The riser assembly 34 then continues downward and leaves bushing 36 retained in keel guide 32 . Locking device 50 may then be actuated to close keel guide 32 such that upward, linear movement of bushing 36 is prevented by the interfering engagement of upper shoulder 86 with bushing member 74 .
In an exemplary application, a plurality of keel guides 32 are attached to a structure such as a hull 114 of a vessel or platform, as illustrated in FIG. 7 . The locking devices 50 on each keel guide are oriented for accessibility by an ROV. By using bushings 36 in each keel guide 32 , connectors or components can be moved downwardly through the center of each keel guide during installation, and the corresponding keel guides 32 and bushings 36 cooperate to prevent the riser assemblies 34 from interfering with each other or hull 114 upon installation.
Another embodiment of keel guide system 30 is illustrated in FIGS. 8 through 10 . A keel guide 32 ′ is coupled to a structure, such as the hull of a vessel or a platform, via bracket 44 . As described above, the inner diameter of the keel guide is large enough to allow passage of a tieback connector or other component attached to the bottom of riser assembly 34 . In this embodiment, bushing 36 is landed on a shoulder 116 formed along an interior surface 118 of keel guide 32 ′. Interior surface 118 has a slightly greater diameter than the remainder of keel guide 32 ′ to permit bushing 36 to move downwardly to shoulder 116 without the use of an expandable side opening.
In the embodiment illustrated, wear bushing assembly 72 , and specifically bushing members 74 , is held against shoulder 116 by one or more lock-down assemblies 120 . Lock-down assemblies 120 may be mounted in a variety of orientations, such as the exemplary plumb mounted lock-down assembly 122 and the obliquely mounted assemblies 124 , illustrated best in FIG. 8 . Lock-down assemblies 120 may be used selectively to prevent upward linear motion of bushing 36 once landed against shoulder 116 , as illustrated in FIGS. 9 and 10 . Specifically, once bushing 36 is landed in keel guide 32 ′, either or both lock-down assemblies 122 and 124 may be actuated by, for example, an ROV to retain bushing 36 against linear motion within keel guide 32 ′. As illustrated best in FIG. 10 , a temporary mounting mechanism 88 and corresponding clamp connector 90 may be used to temporarily hold bushing 36 in place with respect to riser assembly 34 while being lowered into keel guide 32 ′.
Exemplary embodiments of a plumb mounted lock-down assembly 122 and an obliquely mounted lock-down assembly 124 are illustrated in FIGS. 11 and 12 , respectively. Each lock-down assembly comprises a sleeve 126 which is attached to keel guide 32 ′ by an appropriate fastening method, such as welding. Each lock-down assembly further comprises an ROV bucket 128 attached to an end of sleeve 126 generally opposite keel guide 32 ′. A lock-down pin 130 is threadably engaged with sleeve 126 at an internal threaded region 132 . A first end 134 of lock-down pin 130 extends into a keel guide opening 136 . As pin 130 is threaded inwardly, the first end 134 moves into the interior of keel guide 32 ′ to prevent upward movement of bushing 36 . In the plumb mounted lock-down assembly 122 , opening 136 is generally radially directed, while opening 136 of obliquely mounted lock-down assembly 124 is oriented at an angle with respect to the radius, as illustrated in FIG. 12 . First end 134 may have a variety of configurations, but one exemplary configuration is a conical tip.
An opposite end 138 of lock-down pin 130 extends into ROV bucket 128 and terminates at a head 140 . Head 140 is adapted for engagement by an external device, such as an ROV manipulator.
One exemplary application of keel guide system 30 in which keel guide 32 ′ is utilized is illustrated in FIG. 13 . In this example, a plurality of keel guides 32 ′ are attached to hull 114 by appropriate brackets 44 . Each of the keel guides comprises a plurality of lock-down assemblies 120 oriented for access by an ROV. Thus, the riser assemblies 34 with attached connectors or other components may be run through corresponding keel guides 32 ′ until each bushing 36 is landed therein. Upon release, e.g. fracturing, of the temporary mounting mechanism 88 , each riser assembly slides linearly downward through its surrounding bushing 36 .
Another embodiment of keel guide system 30 is illustrated in FIGS. 14 through 16 . In this embodiment, a keel guide 32 ″ is coupled to bracket 44 for connection to an appropriate structure, such as the hull of a vessel or platform. As with previously described embodiments, the inner diameter of keel guide 32 ″ may be large enough to allow passage of a connector, such as a tieback connector, or other component attached to the bottom of riser assembly 34 .
In this embodiment, bushing 36 is landed in a landing feature 142 that is in the form of bowl 144 defined by an upper interior surface of keel guide 32 ″ (see FIG. 15 ). Bowl 144 is shaped to receive a wear bushing assembly 146 of bushing 36 . Specifically, the exemplary wear bushing assembly 146 comprises one or more radially extending bearing members 148 having interior wear inserts 150 . Wear inserts 150 are positioned to bear against keel joint 38 . Additionally, wear bushing assembly 146 also comprises a plurality of retention members 152 that retain bushing 36 against upward movement within keel guide 32 ″. In other words, the shape of bowl 144 allows wear bushing assembly 146 to move downwardly into keel guide 32 ″ until further movement is blocked by landing feature 142 . Once positioned against landing feature 142 , retention members 152 may be actuated to impede upward movement of bushing 36 , as illustrated in FIG. 14 .
In this embodiment, bushing 36 also may comprise a temporary retention mechanism 154 by which bushing 36 is temporarily coupled to riser assembly 34 during installation of bushing 36 into keel guide 32 ″. One exemplary retention mechanism 154 comprises a clamp connector 156 that may be clamped around riser assembly 34 . Clamp connector 156 is coupled to wear bushing assembly 146 via posts 158 and shear pins 160 . As riser assembly 34 is lowered through the interior of keel guide 32 ″, bushing 36 moves with riser assembly 34 until landed in landing feature 142 . The weight of riser assembly 34 shears shear pins 160 , and riser assembly 34 continues downward movement through keel guide 32 ″ while bushing 36 is retained within the keel guide. Subsequently, retention members 152 may be actuated to impede upward movement of bushing 36 with respect to keel guide 32 ″.
One exemplary embodiment of retention mechanism 152 is illustrated in FIG. 16 . In this embodiment, retention member 152 comprises a plurality of spring-loaded assemblies 162 . Each spring-loaded assembly has a pin that is biased outwardly by a spring 166 . Pin 164 and spring 166 may be mounted in a corresponding bore 168 formed in bearing member or members 148 . Spring 166 biases pin 164 towards a retention groove 170 formed in the interior wall of keel guide 32 ″. Once pin 164 is biased into engagement with groove 170 , upward movement of bushing 36 is inhibited. A retainer, such as a screw 172 , may be used to partially block bore 168 and thereby retain pin 164 within bore 168 .
As illustrated in FIGS. 17 and 18 , an external wear sleeve 174 may be utilized between bushing 36 and keel joint 38 . The wear sleeve 174 may be attached to keel joint 38 by, for example, press fitting, shrink fitting or other suitable techniques. Wear sleeve 174 protects keel joint 38 from wear and damage as keel joint 38 moves within keel guide 32 . In one example, wear sleeve 174 may comprise a radially inward backup ring 176 coupled to an external wear layer 178 by, for example, welding. In this example, backup ring 176 comprises a feature 180 , such as a split in the material. Feature 180 can be engaged with a corresponding feature 182 on keel joint 38 to limit relative movement between keel guide 38 and wear sleeve 174 . Alternatively, backup ring 176 may comprise or may be replaced with a thicker elastomeric material to enable greater flexibility within the keel guide. The thicker elastomeric material may comprise, for example, a poured or castable material, such as a foam.
Another embodiment of keel guide system 30 is illustrated in FIGS. 19 through 23 . In this embodiment, a keel guide 32 ′″ is mounted to a structure, such as the hull of a vessel or platform by a bracket 44 . Again, the inner diameter of keel guide 32 ′″ may be large enough to allow the passage of a connector, such as a tieback connector, or other component attached to the bottom of riser assembly 34 . Bushing 36 is landed within the interior of keel guide 32 ′″ to limit radial movement of riser assembly 34 while allowing relative linear movement between riser assembly 34 and keel guide 32 ′″. Bushing 36 comprises a bushing assembly 184 having at least one and typically a plurality of wear inserts 186 that bear against keel joint 38 of riser assembly 34 . Additionally, a retention mechanism 188 is used to retain bushing 36 within keel guide 32 ′″, as illustrated in FIGS. 19 and 20 .
One exemplary retention mechanism 188 comprises a plurality of swinging lock-down pin assemblies 190 (see FIG. 19 ). Additionally, a temporary retention mechanism may be used to hold bushing 36 to riser assembly 34 during installation of bushing 36 in keel guide 32 ′″, as with the embodiments described above. In this embodiment, the plurality of pin assemblies 190 , e.g. four pin assemblies, cooperate to restrain bushing 36 against linear movement with respect to keel guide 32 ′″ once the bushing is landed within the keel guide.
As illustrated in FIGS. 21 through 23 , one exemplary type of pin assembly 190 comprises a body 192 having a bore or other type of opening 194 to slidably receive a lock-down pin 196 . Lock-down pin 196 is biased radially outwardly by a spring 198 disposed within bore 194 . Each lock-down pin 196 is retained in its corresponding bore 194 by a retaining screw 200 .
Pin assemblies 190 may be mounted at a lower region of bushing 36 beneath a wear bushing assembly 202 . Each pin assembly 190 may be coupled to the underside of wear bushing assembly 202 by sets of brackets and pins. For example, a pair of outer brackets 204 are attached to wear bushing assembly 202 at a radially outlying region by, for example, welding or other suitable attachment technique (see FIG. 22 ). A second set of brackets 206 are similarly attached below wear bushing assembly 202 radially inward from the set of brackets 204 (see FIG. 23 ). Body 192 is secured to the second, inward set of brackets 206 via a pin 208 . Additionally, body 192 is secured to the first, radially outward set of brackets 204 via shear pins 210 , which are threaded into outer brackets 204 . An undercut 212 is formed, e.g. machined, to an underside of wear bushing assembly 202 proximate each second, radially inward set of brackets 206 .
During deployment, bushing 36 is run into keel guide 32 ′″ in a manner similar to that of the embodiments described above. When the wear bushing assembly 202 enters keel guide 32 ′″, the outer end of each lock-down pin 196 contacts a tapered surface 214 formed along the interior surface of keel guide 32 ′″. The lock-down pins 196 ride against tapered surface 214 and are cammed inward into their corresponding bores 194 against the biasing force of the corresponding spring 198 . As wear bushing assembly 202 is moved downwardly into keel guide 32 ′″, the lock-down pins 196 are moved past tapered surface 214 and into proximity with a groove 216 . The springs 198 force corresponding lock-down pins 196 outwardly into groove 216 . An upper edge or shoulder 218 that defines the upper extent of groove 216 forms a locking taper with the lock-down pins 196 . This prevents pins 196 from being cammed inward by moderate upwardly directed loads on the bushing 36 .
If bushing 36 is to be retrieved, riser assembly 34 is raised until the installation clamps, e.g. clamp connector 154 , contacts wear bushing assembly 202 . When sufficient upward force is applied to bushing 36 , shear pins 210 are sheared. This allows each pin assembly 190 to swing about pin 208 so the lock-down pin 196 clears groove 216 . The undercut region 212 formed in wear bushing assembly 202 provides clearance for the pivoting of body 192 . Upon retrieval of bushing 36 , shear pins 210 may be replaced.
Another embodiment of keel guide system 30 is illustrated in FIGS. 24 through 27 . In this embodiment, a keel guide 32 ″″ may be mounted to a structure, such as the hull of a vessel or platform. As with the embodiments described above, the inner diameter of keel guide 32 ″″ may be made large enough to allow passage of a connector, such as a tieback connector, or other component attached to the bottom of riser assembly 34 . In this embodiment, keel guide 32 ″″ has a longitudinal side opening 222 that extends along the length of the keel guide. Side opening 222 allows the diameter of the keel guide to be increased and decreased a small amount by expanding and contracting, respectively, side opening 222 . A locking device 224 , such as a band-type locking device, is used to expand or contract side opening 222 . An exemplary bushing 36 may be designed similar to that described with reference to FIGS. 2 and 5 .
Locking device 224 comprises a first set of brackets 226 and 228 (see FIGS. 26 and 27 ) that are attached to an exterior of keel joint 32 ″″ by, for example, welding or other suitable attachment technique. The first set of brackets 26 , 28 are located on one side of opening 222 . A first pivot pin 230 is rotatably mounted in brackets 226 , 228 and is retained by a suitable mechanism, such as a washer 232 and a screw 234 .
A second set of brackets 236 and 238 are attached to the exterior of the keel joint, on a side of opening 222 opposite brackets 226 , 228 , by welding or other suitable technique. A second pivot pin 240 is rotatably mounted in brackets 236 , 238 and is retained by an appropriate mechanism, such as a washer 242 and a screw 244 . The first set of brackets 226 , 228 is provided with notches, such as notches 246 , and the second set of brackets 236 , 238 is provided with comparable notches, such as notches 248 (see FIG. 24 ). Notches 246 and 248 are designed for engagement by an ROV clamping tool of the type used in subsea operations.
A stud 250 (see FIGS. 26 and 27 ) is disposed through a hole 252 in first pivot pin 230 and through a second hole 254 disposed through second pivot pin 240 . The rotation of stud 250 is prevented by, for example, a screw 256 which engages a slot 258 in a head 260 of stud 250 . The other end of stud 250 is threaded into a blind bore 262 of a locking device bushing 264 . After stud 250 is threaded partially into bore 262 , a retaining screw 266 is screwed transversely into the side of stud 250 . Screw 266 prevents inadvertent separation of stud 250 from locking device bushing 264 .
An open end 268 of locking device bushing 264 is disposed proximate to or bears on pivot pin 240 to prevent further separation of locking device 224 . Opposite open end 268 , locking device bushing 264 is attached to an actuator 270 , such as a T-handle. The T-handle is attached via a fastener, such as a bolt 272 . By way of example, actuator 270 may comprise a cross-bar 274 adapted to be gripped for rotation by an ROV tool.
To adjust locking device 224 and increase or decrease the effective diameter of the keel guide, notches 246 , 248 are engaged by an ROV, and the two sides of the locking device are squeezed more closely together. Another ROV tool is then utilized to rotate actuator 270 , e.g. a T-handle, to turn bushing 264 relative to stud 250 . Depending on the direction of rotation, the distance between the head of stud 250 and locking device bushing 264 can be increased or decreased. Because the ROV is squeezing the locking device together, the spring force of keel guide 32 ″″ is not bearing on stud 250 and locking device bushing 264 . Accordingly, a smaller amount of torque is required to rotate the locking device bushing 264 .
Once the bushing 264 has been adjusted as desired, the ROV releases the sides of the locking device 224 , and the keel guide expands to its adjusted diameter. Accordingly, the diameter of the keel guide can be decreased or increased to hold or release the bushing 36 , as described with respect to the embodiment illustrated in FIGS. 2 and 5 .
It should be understood that the foregoing description is of exemplary embodiments of this invention, and that the invention is not limited to the specific forms shown. For example, the keel guide system may be utilized in a variety of environments with a variety of riser assemblies; the size and shape of the keel guide may be adjusted depending on the size and shape of connectors or other components that pass through the keel guide; the configuration of the landing mechanisms, retention mechanisms and locking devices may be changed; and the size and configuration of various components can be adjusted according to a desired application. These and other modifications may be made in the design and arrangement of certain elements without departing from the scope of the invention as expressed in the appended claims. | A technique for guiding a riser in an offshore environment. The technique utilizes a keel guide that permits the passage of connectors or other components therethrough. A bushing is mounted within the keel guide to guide the relative linear motion of the riser assembly through the keel guide. | 4 |
BACKGROUND OF THE INVENTION
In the manufacture of tissue products, such as facial tissue and bath tissue, constant attention has been given to ways to improve softness of the product as perceived by the consumer. For example, it has long been known that the use of Eucalyptus fibers improves the perceived softness of tissue products and such fibers have been incorporated into commercially available products for years. Other efforts to improve softness have focused on the creping step and the attendant adhesion of the uncreped web to the creping cylinder. Layering has also received considerable attention, particularly by placing the Eucalyptus fibers in the outer layers to maximize the tactile response. All of these approaches have their place in improving the perceived softness of tissue products, but there are other factors to consider which, until now, have not been fully appreciated.
SUMMARY OF THE INVENTION
The invention resides in the use of sliced fibers for the manufacture of tissue products. It has been discovered that a key to achieving improved softness in tissue products lies in the Coarseness Index of the fibers used to form the product. The Coarseness Index for any given species of fiber or any fiber furnish is the weight per unit length of fiber (e.g. milligrams per 100 meters) and is defined as follows: ##EQU1## where (F/G)=millions of fibers per gram of fiber; and
(L)=the numerical average length of the fibers in millimeters.
To fully understand the meaning of the Coarseness Index, it is important to distinguish coarseness from slenderness, which is a different parameter. Fiber slenderness is the ratio of fiber length to fiber diameter. This concept does not take into account the density of the fiber material or the thickness of the fiber wall for hollow fibers. Hence two fibers of the same length and outside diameter, but differing in wall thickness, will have the same slenderness but different coarsenesses. At the same time, a very long fiber having a thick diameter may have a high slenderness but may also have a high coarseness. The difference between coarseness and slenderness can be significant and can be the difference between a soft sheet and a stiff sheet. It is also important to note that coarseness is not directly a function of fiber length. A fiber having a given Coarseness Index will still have the same Coarseness Index after being shortened because the fibers per gram of fiber will be increased in the same proportion as the length reduction, thereby netting no change. This of course is not the case with slenderness, in which case the slenderness of the fiber is reduced in proportion to the length reduction.
With the foregoing in mind, it has now been discovered that fiber species having a high Coarseness Index (therefore imparting a relatively low softness to a tissue product) can be sliced lengthwise to decrease the Coarseness Index of the fibers used in the tissuemaking furnish. As a result, the softness of the tissue product made with the sliced fibers is softer than the tissue product made with the natural or original fibers. The fibers to be split can be woody fibers, nonwoody fibers, or synthetics. For purposes herein, the term "sliced fibers" means fibers that have been cut generally lengthwise, as contrasted with fibers which have been cut crosswise. Ideally, sliced fibers have not been reduced in fiber length relative to the original fibers. However, as a practical matter, fiber shortening is difficult or impossible to avoid from a process standpoint. The amount of sliced fibers in a tissue product necessary to exhibit a measurable softness benefit is believed to be about five (5) weight percent. For purposes of this invention, the amount of sliced fibers can be from about 5 to 100 weight percent of the fiber content of the tissue product.
For purposes herein, "tissue product" means a product having one or more fibrous sheets, preferably creped, each sheet having a dry basis weight of from about 5 to about 40 pounds per 2880 square feet, preferably from about 5 to about 25 pounds per 2880 square feet, and most preferably from about 5 to about 10 pounds per 2880 square feet. Bulk densities for tissue products are typically less than about 0.20 grams per cubic centimeter and often are less than about 0.15 grams per cubic centimeter. Products such as facial tissue, bath tissue, paper towels, and dinner napkins are specific examples of tissue products within the meaning of this invention.
DETAILED DESCRIPTION OF THE INVENTION
Twenty-year-old disks of southern yellow pine (one inch thick) were cut to provide blocks containing the last ten years of growth. Block size was approximately 4 inches×4 inches. Each block was radially cut in half to provide two mirror image samples of each block, one to be used for fiber slicing in accordance with this invention and the other to be used as a control. Each sample was soaked in water for several days to achieve complete swelling and ease the subsequent slicing process. One of the two samples from each block was sliced with a sliding microtome (A. O. Spencer Model 860, Gaithersburg, MD) in a direction parallel to the radial direction of the original wood disk. The microtome was set to cut slices every 15 micrometers. The control samples from each block were cut into toothpick-size chips. Both the sliced and the chipped wood were pulped to equivalent yields with a standard kraft cook in a small-scale, oil-heated laboratory digester and made into handsheets for analysis.
Average fiber length for each sample (reported in millimeters) was determined using a commercially available instrument (Kajaani Model FS-100 available from Kajaani Automation, Inc., Norcross, Georgia). While this particular instrument is highly sophisticated, average fiber length can be determined by other means as those familiar with fiber measurements will appreciate. Tensile strength (dry) and elastic modulus were determined with a Model 1130 Instron, including a recorder and Microcon 1 along with Modulus and Yield Option and stackable speed reducer, available from, Instron Corporation, Canton, Massachusetts. Test samples of handsheets had a basis weight of about 24-25 pounds per 2880 square feet and were cut to a width of one inch. Tensile strength measurements are reported in grams. Modulus is reported in kilometers (modulus/(sample width)(basis weight)). Opacity (Tappi) was measured by using an opacimeter which measures the ratio of light reflected from a paper sample when the sample is backed by a perfectly black body to that when the sample is backed by a white body of 89% reflectance.
The results of pulping the sliced and chipped samples are summarized in Table 1 below.
TABLE 1______________________________________ Pulp Yield Average Fibers per CoarsenessSample (%) Fiber Length Gram (× 10.sup.6) Index______________________________________Chipped 50 3.6 0.85 33.2Sliced 52 0.8 6.83 18.1______________________________________
The results clearly show the effectiveness of fiber slicing as a means to lower the Coarseness Index. At the same time, however, the average fiber length was also substantially reduced due to cross-directional cutting of fibers within the sample blocks. Nevertheless, fiber shortening was simultaneously counteracted by an increase in the number of fibers per gram. The net result was a reduction in the Coarseness Index of from 33.2 to 18.1.
Table 2 shows the results of forming chipped and sliced kraft pulp fibers into handsheets, which was carried out in a conventional manner well known to those skilled in the papermaking arts. The properties of the resulting handsheets are set forth below.
TABLE 2______________________________________ Pulp Yield Tensile/Sample (%) Tensile Modulus Modulus Opacity______________________________________1 (Chipped) 68 102 9.7 109 79.42 (Sliced) 72 148 8.8 174 82.33 (Chipped) 56 321 22.8 146 86.24 (Sliced) 60 328 20.9 163 88.15 (Chipped) 49 474 31.7 156 63.36 (Sliced) 50 833 39.7 218 71.8______________________________________
The results set forth in Table 2 illustrate that in each case the sliced fibers increase the tensile/modulus ratio. This ratio is a measure of the sheet flexibility and hence softness. Hence the sliced fibers improved the softness of the sheet. They also improved the opacity of the sheet, which is also desirable for purposes of consumer preference.
It will be appreciated that the foregoing examples, shown for purposes of illustration, are not to be construed as limiting the scope of this invention, which is defined by the following claims. | Tissue products, such as facial and bath tissue, are provided with improved softwood and opacity by making the products from a furnish containing fibers of a lower coarseness created by splitting the fibers in the lengthwise direction. | 3 |
FIELD OF THE INVENTION
The present invention is related to a fixation system. More particularly, the invention is related to a fixation system with at least one spring beam retainer device for preventing fastener back-out.
BACKGROUND OF THE INVENTION
Orthopedic fixation devices such as plates are frequently coupled to bone with fasteners inserted through plate holes. It is known that securing such fasteners to the bone plate, for example through the use of expansion-head screws, can decrease the incidence of loosening of the fixation assembly post-operatively. It is also known that a bushing may be disposed in each plate hole to receive the fastener to permit polyaxial movement so that the fastener may be angulated at a surgeon-selected angle. However, polyaxial movement of fasteners through set plate hole locations only increases attachment alternatives of the fasteners themselves. The plate holes remain fixed in relation to each other and to the longitudinal axis of the plate.
Typically, a spinal fixation plate is applied to the anterior side of the affected vertebrae to span at least one affected disc space or vertebra (i.e. one in which at least a portion of the disc has been removed and a spinal fusion spacer has been inserted). The plate is fixed to the vertebrae using bone screws and acts to keep the vertebrae generally aligned during the initial period following fixation in which fusion of the spacer to the adjacent vertebrae occurs. The plate also acts to prevent the spacer from being expelled from the disc space during this initial period.
Where a spinal fusion spacer is implanted between a pair of vertebrae to be fused, the spacer rests on the endplates of the vertebrae. The outer circumference of the end plates comprises hard cortical bone and thus provides a the best surface upon which to seat the spacer. The center portion of the endplates comprises a thin cortical bone shell overlying a core of softer cancellous bone. Most, if not all, of the spacer contact surface, however, may be located in this center portion.
Subsequent to placement of the spacer, the surgeon typically compresses the disc space by pressing the adjacent vertebrae together. This compression ensures a good engagement between the spacer the endplates, increasing the chances that fusion will occur. Often in the period immediately following surgery, the spacer will subside slightly either into the under-portion of the endplates or due to graft resorption (in the case of allograft spacers).
Where a rigid fixation plate is used to connect the vertebrae, this subsidence may tend to shift more of the spinal load to the plate than is desirable. Such load shifting can also occur due to inaccuracies in installing the plate to the vertebrae. In extreme circumstances, this load shifting can result in non-fusion of the spacer to the vertebra, since firm compression between the spacer and the vertebrae is one factor contributing to successful fusion.
Accordingly, there exists a need for a fixation system which provides the desired support to the vertebrae to be fused, and which allows limited translation of the vertebrae with respect to at least a portion of the plate, thereby limiting the undesirable effects of load shielding by the plate due to graft subsidence caused by settling or normal forces experienced in the spinal column. Promoting fusion of the adjacent vertebrae is thus accomplished.
However, fasteners used with both rigid and translational plates have a tendency to back-out of their installed positions under the influence of force and movements of the spine. The back-out of the fasteners is undesirable, as the fixation assembly may shift post-operatively to an undesired location, or loosen to an undesirable level.
Therefore, there exists a need for a fastener retaining device that can be coupled to a translational plate for preventing screw back-out. There also exists a need for such a retainer device to be conveniently situated in or around the plate, so as not to interfere with the insertion and/or placement of fasteners. There further exists a need for a retainer device to be bendable and/or shiftable by a surgeon without the use of strenuous force.
SUMMARY OF THE INVENTION
A fixation assembly is described, comprising a fixation plate having an upper surface, a lower surface, a longitudinal axis, and a first opening extending from the upper surface through to the lower surface; a first resilient element extending through at least a portion of the first opening; wherein the first opening is configured to receive a first bone fastener, the first bone fastener having a head and a shaft; wherein the first resilient element is deflectable from a first condition to a second condition; and wherein the first resilient element is configured to engage at least a portion of the head of the first bone fastener when the first bone fastener is at least partially inserted into the first opening.
The first bone fastener may be allowed to translate within the first opening. The first bone fastener may be allowed to translate in situ. The first bone fastener may be allowed to translate when at least a portion of the first bone fastener is inserted into a bone segment.
The first opening may be a slot. The first resilient element may be substantially parallel to the longitudinal axis of the fixation plate when the first resilient element is in the first condition. The head of the first bone fastener may further comprise at least one slot, wherein the slot may be configured to engage at least a portion of the first resilient element.
The assembly may further comprise a second opening having a second resilient element extending though at least a portion of the second opening. The first opening may have a centerline, wherein the first resilient element may be fixed to the fixation plate at a first and a second location, and wherein the first and second locations may be substantially collinear with the centerline. The first resilient element may be substantially linear in the first condition, wherein the first resilient element may be bowed in the second condition.
A fixation assembly is also described, comprising a fixation plate having an upper surface, a lower surface, a longitudinal axis, and a first opening extending from the upper surface through to the lower surface; a first resilient element extending into at least a portion of the first opening, and fixed to the plate at a first location; wherein the first opening is configured to receive a first bone fastener; and wherein the first resilient element is configured to engage at least a portion of the first bone fastener to prevent fastener back-out while allowing the first bone fastener to translate within the first opening.
The first resilient element may be substantially parallel to the longitudinal axis of the fixation plate when the first resilient element is in the first condition.
The first bone fastener may further comprise a head, the head may have at least one slot, and wherein the slot may be configured to engage at least a portion of the first resilient element. The assembly may further comprise a second opening having a second resilient element extending though at least a portion of the second opening. The first opening may have a centerline, wherein the first resilient element may be further fixed to the fixation plate at a second location, and wherein the first and second locations may be substantially collinear with the centerline.
A method of preventing fastener back-out in a fixation assembly is also described, comprising the steps of: (a) providing a fixation plate having an upper surface, a lower surface, a longitudinal axis, and a first opening extending from the upper surface through to the lower surface; a first resilient element extending through at least a portion of the first opening, the first resilient element having a longitudinal axis; wherein the first bone fastener has a head and a shaft; and wherein the first resilient element is deflectable from a first condition to a second condition; (b) initially deflecting the first resilient element in a direction substantially transverse to the longitudinal axis of the first resilient element; and (c) inserting the first bone fastener through the first opening and into a bone segment; wherein the first bone fastener is inserted to a sufficient depth to allow the first resilient element to engage the head of the first bone fastener.
The first resilient element may be initially deflected by the shaft of the first bone fastener. The first resilient element may be initially deflected directly by a user.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred features of the present invention are disclosed in the accompanying drawings, wherein similar reference characters denote similar elements throughout the several views, and wherein:
FIG. 1 is a top view of an embodiment of a one-level bone fixation assembly with fasteners and spring beam retainer devices;
FIG. 2 is a partial enlarged top view of the assembly of FIG. 1 without a fastener, the spring beam retainer device in an unstressed, unengaged position;
FIG. 3 is a partial cross-sectional view of the assembly of FIG. 2 taken on the line A-A;
FIG. 4 is a partial cross-sectional view of the assembly of FIG. 2 taken on the line A-A, with a fastener engaging a spring beam retainer device and implanted into a vertebra;
FIG. 5 is a partial enlarged top view of the assembly of FIG. 1 with a fastener, the spring beam retainer device in an stressed, unengaged position;
FIG. 6 is a partial cross-sectional view of the assembly of FIG. 5 taken along the line B-B; and
FIG. 7 is a partial enlarged top view of the assembly of FIG. 1 with a fastener, the spring beam retainer device in an unstressed, engaged position.
DETAILED DESCRIPTION OF THE INVENTION
The plates described herein may be used in spinal fusion procedures in which a damaged or diseased disc (or part of a disc) is removed from between a pair of vertebrae and a spinal fusion spacer is placed between the vertebrae. The plates may be applied to an anterior portion of the affected vertebrae to span the affected disc space, and may be fixed to the vertebrae using bone screws. The plate may function to maintain the vertebrae aligned during the initial period following fixation in which fusion of the spacer to the adjacent vertebrae occurs. The plate may also function to share some of the axial spinal load applied to the fusion spacer to prevent extreme subsidence of the spacer into the vertebral body, such as where the patient has poor bone quality. The plates may also act to prevent the spacer from being expelled from the disc space during the initial post-operative period.
The plates may be used for single level (i.e. one-disc) or multiple-level (i.e. multiple disc) fusion procedures. Some embodiments may be used for corpectomy procedures, in which at least a portion of a vertebral body is removed. Single level plates generally may have two pairs of bone screw holes, while the multi-level plates generally may have three or more pairs of holes.
FIGS. 1-7 shows a one-level bone fixation assembly 10 . This embodiment includes a bone fixation plate 12 which, in this particular example, may be a spinal fixation plate. A plurality of fasteners 14 may extend through openings 15 in the plate 12 . A plurality of spring beam retainer devices 18 may be coupled to the plate 12 . The retainer devices 18 may engage the fasteners 14 to restrain them from rotating back outward from their installed positions when the screws 14 and the plate 12 are together mounted on the spine.
The plate 12 may be configured to overlie the a section of the spine to provide support that maintains the alignment of two or more vertebrae in that section of the spine. As shown in FIG. 1 , this example of a plate 12 has a vertically elongated generally rectangular shape with rounded corners, and may have planar upper and lower side services 20 and 22 . The thickness and material of the plate 12 may enable a surgeon to deflect it from a flat configuration as needed for the plate 12 to extend over the spine with an appropriate contour.
The openings 15 may be arranged in pairs at the first and second end portions of the plate 12 . In this arrangement, the first pair of fasteners 14 at the first openings 15 can fasten the plate 12 to a first vertebra, and the second pair of fasteners 14 at the second openings 15 can fasten the plate 12 to a second vertebra beneath the first vertebra. Additionally, the openings 15 in at least one pair may be shaped as elongated slots. In this example, both pairs of openings 15 may be shaped as elongated slots. This may permit the first and second pairs of fasteners 14 to translatably move within the slots 15 when compression of the spine causes first and second vertebrae to move relatively toward each other lengthwise of the plate 12 . Slots 15 may also be fitted with captive clips (not shown) to allow fasteners 14 to move within the slots 15 and further prevent fastener 14 back-out, the details, materials, and methods of which are described in U.S. patent application Ser. No. 10/653,164 entitled “Bone Plate with Captive Clips”, by Duong, et al., filed Sep. 3, 2003, the entire disclosure of which application is expressly incorporated by reference herein.
It may be preferable to have each slot 15 of substantially the same dimension, size and shape. Each slot 15 may have the configuration as shown in FIGS. 2-3 . Each slot 15 may thus defined by inner edge surfaces of the plate 12 that together extend through the plate 12 between the opposite side surfaces 20 and 22 . A first inner edge surface 30 may provide the slot 15 with a substantially rectangular peripheral shape adjacent to the upper side surface 20 of the plate 12 . A second inner edge surface 32 may provide the slot 15 with a generally shorter and narrower shape, with rounded opposite ends, adjacent to the lower side surface 22 . A first shoulder surface 34 may have a planar contour facing upward within the slot 15 . A second shoulder surface 36 may be located between the first shoulder surface 34 and the second inner edge surface 32 . That shoulder surface 36 may also face upward, but may have a contour with an generally arcuate profile, as shown in FIG. 3 .
Thus, slot 15 may be configured to provide a path of movement along which a fastener 14 is movable into and back outward from an installed position in which the fastener 14 fastens the plate 12 to a vertebra 40 , as shown in FIG. 4 . As the fastener 14 is being tightened into this position, an arcuate lower surface 42 of the fastener head 44 may become seated against the arcuate inner edge surface 36 within the slot 15 . It may be preferable for the entire fastener head 44 to be located within the slot 15 between the upper and lower side surfaces 20 and 22 of the plate 12 .
As further shown in FIGS. 2-3 , a generally shaped region 51 of the slot 15 may be located above the planar shoulder surface 34 . The shaped region 51 may be bounded by the first inner edge surface 30 . An inner peripheral region 53 of the slot 15 may surround the shaped region 51 . The inner peripheral region 53 may be bounded by an inner edge surface 54 that may be recessed from the first inner edge surface 30 around the entire length of the first inner edge surface 30 . As shown in FIG. 2 , the recessed inner edge surface 54 may define opposite end portions 55 of the inner peripheral region 53 . Those portions 55 may be configured as bores that extend oppositely along the longitudinal centerline 57 of the slot 15 .
It may also be preferable for the spring beam retainer devices 18 to be similarly dimensioned, sized, and shaped, as shown in FIGS. 2-3 . In this particular example, each spring-loaded retainer device 18 takes the form of a wire spring 70 . The spring 70 may be shaped as a bar having a generally rectangular cross-section, with rounded corners, substantially uniform along its length. Opposite end portions 72 of the spring 70 may be received closely within the bores 55 to slide longitudinally within the bores 55 . The spring 70 may thus be mounted on the plate 12 to be shifted from a first, unstressed, unengaged condition, as shown in FIG. 2 , to a second, stressed, unengaged condition, as shown in FIG. 5 , under an applied force, and to rebound from the second condition to either a third, unstressed, engaged condition (if fastener 14 is present), or back to the first, unstressed unengaged condition (if no fastener 14 is present) upon release of the applied force.
In this embodiment, the first condition (see FIG. 2 ) of the spring 70 is an unstressed, unengaged rest condition. In this first condition, intermediate portion 74 of the spring 70 may extend longitudinally between the opposite end portions 72 in a linear configuration centered on the longitudinal centerline 55 of the slot 15 . The second condition (see FIG. 5 ) of the spring 70 is a stressed, unengaged condition in which the intermediate portion 74 may be bowed between the opposite end portions 72 , which then may be drawn slightly outward from their rest positions within the bores 55 . Accordingly, when the spring 70 is in the first condition, the intermediate portion 74 of the spring 70 may extend into the path of movement that the fastener 14 may take through the slot 15 toward and into its installed position as it is being implanted into a vertebra 40 . When the spring 70 is in the second condition, it is generally located outside the path of movement of the fastener 14 .
In use, the spring 70 may be urged from the first condition to the second condition by the lower arcuate surface 42 of the fastener 14 as the fastener is lowered into the slot 15 . Initially, the spring 70 may be pushed to one side or the other of the fastener 14 , as the fastener is introduced into the slot 15 . This initial push may be achieved by the surgeon using his or her hand (or a tool) to deflect the spring 70 in a desired direction. As the fastener 14 proceeds further into the slot 15 , and the screw head engages the spring 70 , the lower arcuate surface 42 may urge the spring 70 into a recessed inner peripheral region 53 of a slot 15 .
After engaging a lower arcuate surface 42 of a fastener 14 , the spring 70 may engage an upper arcuate surface 46 as the fastener 14 is further introduced into slot 15 . The spring 70 may remain in a recessed inner peripheral region 53 until the resilient restoring force attempting to return the spring 70 to the unstressed position is sufficient to overcome the axial force provided by the fastener head 44 . An example of this scenario is seen, just before spring 70 returns to an unstressed condition, in FIG. 6 . The relationship between the magnitude and/or direction of the resilient force of spring 70 and axial force provided by fastener head 44 is at least in part determined by the shape of the lower and upper arcuate surfaces 42 , 46 , and the cross-sectional shape and/or surface features of the spring 70 .
Once spring 70 is able to shift back toward the unstressed condition, it may slide and/or rotate over at least a portion of the upper arcuate surface 46 of fastener head 44 , and ultimately may settle in a driving tool slot 81 of fastener head 44 . As stated above, spring 70 may be situated in a third, unstressed condition when a fastener 14 is inserted into slot 15 . Spring 70 may rest either completely or partially in driving tool slot 81 while in the third condition, and may block the fastener 14 from rotating relative to the plate 12 , as shown in FIGS. 4 and 7 . This may restrain the fastener 14 from backing out of the installed position in which it has been implanted into a vertebra 40 . However, the engagement of the spring 70 (in a third condition) with a fastener head 44 generally should not interfere with the ability of fastener 14 to translate within a slot 15 , while the fastener 14 is inserted into a vertebrae 40 and/or in situ.
Spring 70 , while shown in a generally rectangular cross-sectional shape, may be a variety of shapes and/or sizes. For instance, spring 70 may have a circular, elliptical, square, triangular, or other polygonal cross-sectional shape. The cross-sectional shape of spring 70 may also vary along the length of the spring. At least a portion of the spring 70 should have a shape and/or size that is appropriate for at least a partial insertion into a chosen driving tool slot 81 of a fastener 14 .
Moreover, spring 70 may also have a variety of surface textures and finishes. Spring 70 may be relatively smooth, or may instead have serrations, grooves, or other surface features on at least a portion of the outer surface of spring 70 . Furthermore, spring 70 may be of uni-body construction, or instead may be comprised of a plurality of layers.
The sizes, dimensions, and shapes of each of the above described fixation plates and other fixation assembly components may be varied to fit the anatomy of a given patient, depending at least in part on the size of the vertebra the plates will be attached to, and the size of the intervertebral space to be spanned. Fixation assemblies may also be substantially flat, to reduce the overall profile of the assemblies.
It is also expressly contemplated that each of the above described fixation assemblies may be assembled in a multi-level arrangement to span more than one intervertebral disc space. It is also contemplated that each of the above described assemblies may be assembled in corpectomy model, to span the length of at least one removed vertebral body. Variations or combinations of these alternatives are also contemplated.
Each of the fasteners, fixation plates, fastener retainers, and other components disclosed herein may be formed of a titanium alloy such as titanium-aluminum-niobium, which may be anodized. One material for use with each of the plates and screws described herein is Ti-6Al-7Nb, with a density of about 4.52 gm/cc, a modulus of elasticity of about 105 GPa, an ultimate tensile strength of about 900 MPa, and a yield strength of about 800 MPa. Surfaces of the fasteners may also be burr free, with all sharp edges broken to a maximum of 0.1 mm. Spring 70 may be made of any biocompatible, resilient material, including elgiloy and nitinol.
It should be noted that the aforementioned descriptions and illustrations have been provided as examples of the configurations of translation plates that may be designed and assembled using the principles of the invention. These examples will be understood to one of ordinary skill in the art as being non-limiting in that a fixation assembly employing one or more of the disclosed features may be produced as desired or required for a particular patient's need. Thus, the features disclosed are “modular” in nature.
This written description sets forth the best mode of the claimed invention, and describes the claimed invention to enable a person of ordinary skill in the art to make and use it, by presenting examples of the elements recited in the claims. The patentable scope of the invention is defined by the claims themselves, and may include other examples that occur to those skilled in the art. Such other examples, which may be available either before or after the application filing date, are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
While the invention has been shown and described herein with reference to particular embodiments, it is to be understood that the various additions, substitutions, or modifications of form, structure, arrangement, proportions, materials, and components and otherwise, used in the practice and which are particularly adapted to specific environments and operative requirements, may be made to the described embodiments without departing from the spirit and scope of the present invention. Accordingly, it should be understood that the embodiments disclosed herein are merely illustrative of the principles of the invention. Various other modifications may be made by those skilled in the art which will embody the principles of the invention and fall within the spirit and the scope thereof. | A fixation assembly is described, comprising a fixation plate having an upper surface, a lower surface, a longitudinal axis, and a first opening extending from the upper surface through to the lower surface; a first resilient element extending through at least a portion of the first opening; wherein the first opening is configured to receive a first bone fastener, the first bone fastener having a head and a shaft; wherein the first resilient element is deflectable from a first condition to a second condition; and wherein the first resilient element is configured to engage at least a portion of the head of the first bone fastener when the first bone fastener is at least partially inserted into the first opening. A method of use is also described. | 0 |
FIELD OF THE INVENTION
The present invention relates to rock crushing machines and more particularly to such machines wherein oscillatory vibration or motion is produced in opposed jaws by means of eccentric masses or the like.
BACKGROUND OF THE INVENTION
U.S. Pat. No. 3,079,096, entitled "Crushing Apparatus" issued Feb. 26, 1963 to David P. McConnell, father of one of the inventors herein. The crusher described and claimed in that patent is particularly representative of the prior art with respect to the present invention and is accordingly discussed in greater detail below. The jaw crusher of the present invention includes certain features in common with the apparatus of the above patent and also in common with a copending application, Ser. No. 06/943,552 entitled "Improved Jaw Crusher with Multiple Drive Means" and filed Dec. 18, 1986 by David P. McConnell, one of the inventors herein.
Accordingly, both U.S. Pat. No. 3,079,096 and the copending application referred to above are incorporated herein as though set forth in their entirety in order to provide a more complete understanding of the present invention particularly as to common crushing apparatus features.
The crushing apparatus of the present invention also includes certain features in common with apparatus disclosed in another copending patent application, Ser. No. 06/823,309 filed Jan. 28, 1986 by David P. McConnell, one of the inventors herein, entitled "Jaw Crushing Apparatus" and now assigned to the assignee of the present invention. Accordingly, that copending and commonly owned reference is also incorporated herein as though set forth in its entirety.
Referring now to the incorporated references, U.S. Pat. No. 3,079,096 disclosed a jaw crusher of the type generally referred to above wherein an eccentric mass was supported for rotation behind each of its opposed jaws. Substantial forces acting upon the jaws were absorbed by resilient means including wheels with pneumatic tires arranged in shoes or cylindrical tracks. In addition to absorbing tremendous shock loading on the jaws, the resilient tires permitted the jaws to move away from each other as necessary when uncrushable material formed, for example, from hardened steel or the like, entered between the jaws.
Accordingly, the jaw crusher of the reference was particularly effective in crushing materials such as rock while preventing the jaws or other portions of the crusher from being damaged by uncrushable material passing between the jaws.
Other jaw crushers including opposed vibratory jaws operated by rotating eccentric masses have also been disclosed in the prior art. For example, reference is made to U.S. Pat. No. 1,247,701 issued Nov. 27, 1917 to Michaelsen. However, at least for purposes of the present invention, these other prior art jaw crushers are believed to be generally equivalent to that of the above incorporated reference.
Although the prior art jaw crushers discussed above were very effective for their purpose, it has been found desirable to further improve their design for further enhancing jaw crusher operation in a variety of applications.
In particular, it has been found that assembly and disassembly is relatively difficult for such crushers with opposed jaws. This is most noticeable in connection with the jaws themselves which tend to experience substantial wear during operation of the crusher and must accordingly be replaced or rebuilt relatively frequently.
Accordingly, there has been found to remain a need for a jaw crusher exhibiting improvements in the areas discussed above as well as in other areas.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an improved jaw crusher capable of overcoming disadvantages such as those discussed above.
It is a further related object of the invention to provide a jaw crusher having an improved design for supporting at least one jaw in floating relation on a frame structure of the crusher while facilitating assembly and disassembly of the crusher, the improved design including upper and lower elongated resilient members connected with the frame structure behind the one jaw, and upper and lower reaction members connected to the one jaw for respective interaction with the upper and lower elongated resilient members, the upper and lower reaction members being formed in substantially diametric relation for encompassing diametrically opposed portions of the upper and lower elongated resilient members in order to permit oscillatory movement of the one jaw in response to the eccentric means while at the same time limiting travel of the one jaw in all directions on the frame structure.
Preferably, the crusher is designed with both jaws being similarly configured and mounted on its frame structure.
It is preferred that the upper elongated resilient member be replaceably connected to the frame structure to facilitate assembly and disassembly of either or both jaws as drop-in units. It is also preferred that the lower elongated resilient member be connected with the frame structure by additional floating mount means for permitting increased movement of the first jaw relative to the frame structure. Such a configuration is described in greater detail within the incorporated copending reference entitled "Jaw Crushing Apparatus". The additional floating mount provided at the bottom of the jaw is particularly important when the overall configuration of the jaw crusher is considered. As described in greater detail below, lower Portions of the jaws converge toward each other and are preferably generally parallel in order to achieve fine crushing of material hefore it exits from the hottom of the crusher. Increased movement made possible by the additional floating mount at the bottom of the jaws allows these portions of the jaws to move even further apart from each other in order to allow uncrushable material to pass through the crusher without damaging or plugging the crusher.
It is yet another related object of the invention to provide an improved crusher jaw of drop-in configuration as described above for use with a crusher. Here again, it is preferably contemplated that two drop-in jaws of similar design be employed in a single crusher.
Additional objects and advantages of the invention are made apparent in the following description having reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of a jaw crusher constructed in accordance with the present invention.
FIG. 2 is a view taken from the left side of FIG. 1 in order to show additional features of the invention.
FIG. 3 is a fragmentary side view of the opposed jaws in the crusher to better illustrate their construction and configuration.
FIG. 4 is a view of one of the jaws taken from the right side of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A jaw crusher constructed according to the present invention is generally indicated at 10 in the drawings and includes a base frame assembly 12 and a fabricated floating irame or jaw carriage structure 14. The base frame assembly 12 includes a platform 16 and upright frame members 18 and 20. Both the base frame assembly 12 and jaw carriage frame 14 are substantially reinforced as illustrated.
The jaw carriage frame 14 includes opposed upright side Plates 24 and 26 which are rigidly interconnected by cross members 28. The jaw carriage frame 14 is resiliently supported upon the base frame 12 by a plurality of coiled springs 30 interposed between the upright frame members 18 and 20 of the base frame 12 and the cross members 28 of the jaw carriage frame 14. The springs 30 are positioned relative to both the upright frame members 18 and 20 and the cross members 28 by means of positioning cups 32.
A pair of crusher jaws 34 and 36 are mounted on the jaw carriage frame 14 in a manner described in greater detail below ior allowing oscillatory or vibratory movement of the jaws in synchronized relation with each other. The mounting of the jaws 34 and 36 upon the jaw carriage frame 14 is of particular importance because of the very substantial shock forces acting upon the jaws during operation of the crusher.
In any event, it will be more apparent from the following description that, in their oscillatory or vibratory movement, the jaws experience an upward stroke where they move upwardly and away from each other followed by a downward stroke where the jaws move downwardly and toward each other. The upward and downward strokes of the jaws produce vibratory and oscillatory movement in order to develop crushing force on rocks or other material passing between the jaws.
As noted above, the crusher jaws 34 and 36 are of substantially similar construction except that they are formed as mirror images of each other. Accordingly the following description for the crusher jaw 34 also applies to the crusher jaw 36 with similar primed numerical labels being employed. Although both jaws 34 and 36 are described as being similarly configured and mounted in the crusher, it is again noted that one jaw could be relatively fixed with the other jaw being mounted in the manner described below.
Referring now particularly to FIGS. 1 and 3, the crusher jaw 34 is formed with an upper hardened face plate 38 and a lower hardened face plate 42. Both plates 38 and 42 are secured to a backing plate 40 preferably by means of countersunk bolts or studs (not shown) in order to permit their removal or replacement on the jaw.
The angular relationship between the upper and lower face plates 38 and 42 on the crusher jaw 34 and the upper and lower face plates 38' and 42' on the jaw 36 is important for achieving more effective crushing action on rocks or other material passing between the jaws.
Generally, it is desirable for the lower face plates 42 and 42' to be substantially parallel with each other, for example, when fine crushing is desired within the crusher 10. At the same time, the upper face plates 38 and 38' form a wider converging angle for receiving material to be crushed in the crusher 10.
For a further discussion of the jaws 34 and 36 and their preferred configuration, reference is made to the incorporated references noted above.
It is again noted that the present invention is particularly directed toward the manner in which the crusher jaws 34 and 36 are supported for oscillatory vibrating movement in the floating frame structure 14. In addition, the invention is particularly concerned with the configuration of the jaws 34 and 36 themselves in order to permit them to be of a drop-in design for facilitating installation and removal of the jaws from the crusher 10.
Continuing with reference to FIGS. 1, 2 and 3, the upper end of the jaw 34 is supported by an elongated resilient member 43 which is connected to the jaw carriage frame 14 and interacts with an upper reaction member 44 attached to or forming an integral portion of the jaw 34.
The lower portion of the jaw 34 is supported relative to the jaw carriage frame 14 by series connected resilient floating mounts 46 and 48. The floating mount 46 comprises an elongated resilient member similar to the upper member 43. Both the upper elongated resilient member 42 and the floating mount or lower elongated resilient member 46 are formed from compressible and resilient tires 50.
A lower reaction member 52 is attached to or integrally formed on a lower portion of the jaw 34 for interacting with the lower elongated resilient member 46.
The tires or wheels 50 in the lower elongated resilient member 46 are arranged upon a shaft or axle 54 which in turn is supported in resilient, floating relation on the jaw carriage frame 14 by the second resilient floating mount 48.
As illustrated in FIGS. 2 and 3, the second resilient floating mount 48 also comprises compressible and resilient tires 56 mounted on opposite ends of the axle 54 and arranged within additional mounting means in the form of rigid shoes or cylindrical tracks 58. Each of the shoes or tracks 58 is rigidly supported by an adjusting block 60 which is positioned, for example, to adjust spacing between the jaws by means of an adjusting screw assembly 62 secured to the base frame assembly 12.
Thus, the combination of the first and second resilient floating mounts 46 and 48 together with similar mounts 46' and 48' for the other jaw 36 provide a number of advantages within the present invention. Initially, they further extend the effective stroke of the jaws as described above for increasing crushing capacity of the apparatus 10 while also more readily permitting uncrushable material or objects to pass between the jaws and out of the crusher without damaging or plugging the crusher. Other advantages for the series connected floating mounts 46 and 48 are set forth in the incorporated reference entitled "Jaw Crushing Apparatus".
It is again noted that oscillating vibratory travel of each jaw, for example, the jaw 34, is permitted by radial spacing between the pneumatic tires 50 and the lower reaction member 52 together with similar spacing between the tires 56 and the cylindrical track 58 of the second resilient floating mount.
The tires 50 in the upper elongated resilient member 42 are similarly arranged upon a shaft or axle 64 which is adjustably and replaceably connected to the jaw carriage frame 14 by means of a replaceable and adjustable mounting blocks 66 and 68 arranged at each end of the axle 64. The replaceable construction for the upper elongated resilient member 43 is important in connection with the drop-in configuration of the jaw 34 as described in greater detail below.
Referring now particularly to FIG. 3, the drop-in configuration for the jaw 34 is particularly dependent upon the configuration for the upper and lower reaction members 44 and 52. Generally, these members are diametrically arranged with relation to each other so that, in combination, they limit travel of the jaw in all directions in response to operation of eccentric means generally indicated at 70 and described in greater detail below.
With the upper and lower elongated resilient members 43 and 46 being formed from cylindrical tires, for example, the upper and lower reaction members 44 and 52 are also cylindrical but limited in extent to less than 180° in order to facilitate their movement relative to the tires 50.
As may be best seen in FIG. 3, the lower reaction member 52 is approximately 180° in extent while being arranged generally above the lower elongated resilient member 46. At the same time, the upper reaction member 44 is arranged generally beneath the upper elongated resilient member 43. Thus, the lower reaction member 52 tends to support the jaw 34 on the jaw carriage frame 14 and to prevent downward travel of the jaw. At the same time, the upper reaction member 44 tends to prevent or limit excessive upward travel of the jaw 34, for example, in response to operation of the eccentric means 68.
Furthermore, because of the arrangement of the reaction members 44 and 52, with the upper elongated resilient member 42 being removed from the jaw carriage frame 14 as described above, the entire jaw 34 can simply be raised upwardly as viewed in FlG. 3 or lowered downwardly ior installation in the crusher. At the same time, the upper reaction member 44 also serves a restraining function in preventing the upper end of the jaw 34 from collapsing inwardly toward the jaw 36, particularly when the crusher is empty.
Referring particularly to FIG. 1, the eccentric means 68 is illustrated as an elongated eccentric mass arranged upon a shaft 72 supported at its opposite ends by bearings 74 on the jaw carriage frame 14. The elongated configuration of the eccentric mass 68 permits it to be of reduced diameter so that it can be mounted more closely adjacent the jaw 34 as may also be seen in FIGS. 2 and 3.
The shaft 72 is connected by means of a universal drive assembly 76 with a drive shaft 78 which is interconnected with a drive motor 80 by drive belts generally indicated at 82. The universal drive assembly 76 permits the shaft 72 to be disconnected from the drive shaft 78 so that the eccentric means 68 can be assembled and disassembled from the crusher 10 as part of the drop-in jaw assembly 34.
Once again, it is noted that the other jaw 36 is of substantially similar construction and mounting as the jaw 34.
Accordingly, there has been described a novel jaw crusher 10 wherein the jaws 34 and 36 are of drop-in configuration for facilitating installation and removal or replacement of the jaws in the crusher. As noted above, this is particularly important since wear is primarily experienced within the jaws themselves.
Various modifications and additions are believed apparent in addition to those specifically discussed above. Accordingly, the scope of the present invention is defined only by the following appended claims. | A jaw crusher has converging and opposed jaws defining a space for passage of material to be crushed. An improved design for supporting the jaws in floating relation on a frame structure of the crusher includes: upper and lower elongated resilient members connected with the frame structure and upper and lower reaction members connected to each jaw for respective interaction with the elongated resilient members, the upper and lower reaction members being substantially diametrically opposed to each other for permitting oscillatory movement of the jaws while at the same time limiting travel of the jaws in all directions on the frame structure. The improved jaw with upper and lower reaction members as described above facilitates drop-in assembly of the jaws in the crusher. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to seismometers, especially those designed to operate on the ocean floor, and more particularly to a method and apparatus for determining the angle of inclination with respect to the vertical assumed by such a unit during its operation and for leveling the seismic motion detectors carried by such a unit. Seismometers have become an integral component of geological research, especially oil and natural gas exploration. More recently a number of seismometers, commonly referred to as "ocean bottom seismometers" ("OBS's"), have been especially designed and built for remote operation on the ocean's floor in conjunction with such exploration. In such operations a seismic disturbance is artificially generated to create seismic shockwaves which pass through the earth and are refracted at interfaces of rock having diffusing densities. The refracted waves propate back to the earth's surface where they are sensed by seismic motion detectors carried in the seismometer. The use of OBS's poses certain problems not generally encountered in dry land seismometer operations. In seismic exploration on land, the persons deploying the seismic motion detector(s) used can take care to position it (them) so as to provide good seismic coupling to the earth. OBS's used today in deep water exploration are positioned either by being lowered on cables or, more generally, by being dropped in free fall from the ocean's surface. The user has minimal control over the placement of the OBS and generally has no idea of the precise nature of the surface on which the OBS has come to rest. Often, the OBS lands in a position which might not provide good coupling to the seismic waves which it is intended to record. The present invention is a simple and inexpensive method for determining the angle of inclination with respect to the vertical (hereinafter referred to simply as "the angle of inclination") assumed by a seismometer in its operating position, such as an OBS on the ocean floor, and an apparatus for preserving the orientation assumed by the seismometer for later measurement of that angle. Knowing the angle of inclination gives the user some idea of the contour of the ocean floor on which the OBS has fallen. This knowledge can also be used with other available information in later constructing the precise location of the unit on the ocean floor and in evaluating the data gathered and the causes of any failure to obtain data or suitable data. The present invention also assures good coupling of the seismic motion detector to the framework of the seismometer resting directly on the ocean bottom through which the seismic waves travel.
The present invention also comprises a method and apparatus for automatically leveling seismic motion detectors employed in a seismometer. Seismic motion detectors such as geophones are commercially available from numerous commercial sources and are in themselves beyond the scope of this invention. Generally, each such detector has a preferred "operating axis", either vertical or horizontal and will sense the component of motion occurring along an axis parallel to its operating axis. Thus, three orthogonally positioned detectors, one vertical and two horizontal, are needed to fully sense all components of seismic motion. Depending upon the nature of the geological investigation being undertaken, as few as one detector may be used. Means must be provided to align the vertically and horizontally operating detectors, where used, parallel and perpendicular to the vertical, respectively, for operation. Because of the nature of their remote operation, OBS's require self-leveling means for their seismic detectors. The use of gimbal arrangements for leveling OBS seismic motion detectors has been described by T. J. E. Francis et al., in the article "Ocean Bottom Seismograph", published in Marine Geophysical Researches 2 (1975), pp. 195-213 and by S. H. Johnson et al., in the article "A Free-Fall Direct-Recording Ocean Bottom Seismograph", published in Marine Geophysical Researches 3 (1975), pp. 103-117. Rex V. Johnson II et al., in the article "A Direct-Recording Ocean Bottom Seismometer" published in Marine Geophysical Researches 3 (1977), pp. 65-85, described the use of a "boat" floating in a liquid in a hemisphere to level seismic motion detectors in an OBS. The present invention is a novel device for leveling such detectors and, more importantly, can more easily and inexpensively be used than either gimbals or a "boat" with a clamping device such as a spring loaded plunger to preserve the orientation assumed by the leveled seismic detectors so that the angle of inclination assumed by the seismometer can subsequently be determined.
RELATED APPLICATIONS
U.S. application Ser. No. 163,757, filed June 27, 1980 "On-bottom Seismometer Electronic System", Bowden et al. describes an electronic system for timing the various functions performed by an on-bottom seismometer. U.S. application Ser. No. 144,092, filed Apr. 28, 1980, Prior, "Release Mechanism for On-Bottom Seismometer", discloses a release mechanism for such a seismometer.
BRIEF SUMMARY OF THE INVENTION
One or more of the seismic motion detectors carried in a seismometer especially designed to operate on the ocean floor is suspended at the end of a shaft protruding from a ball rotating in an annular seat to form a free moving pendulum. A spring loaded plunger, positioned above the ball, is restrained from contact with its surface by a pin which passes perpendicularly through the plunger and is connected to a linearly acting solenoid. After the seismometer has been positioned for operation, the solenoid is activated by appropriate means causing the pin to be pulled from the plunger which, under the force of its spring, extends to contact the surface of the ball locking it, the shaft and detector(s) in their positions.
The detector(s), support means, solenoid and plunger are preferably mounted to the door of a water-tight instrument housing, a component of the seismometer. In the locked position, there is a rigid connection from the detector(s) through the support means to the door of the water-tight instrument housing which itself is rigidly mounted to the seismometer frame. The frame rests directly on the ocean floor when the seismometer is deployed. The water-tight instrument housing, which is preferably mounted on the lowest portion of the frame, will also tend to embed itself if the ocean floor is mud. This provides a good path for seismic waves traveling through the ocean floor to the chassis of the water-tight compartment. The seismic waves are, in turn, coupled through the rigid connection to the detector, thereby providing better recording of seismic refraction waves than has been provided with prior art devices. After recovery, the angle of inclination that the seismometer assumed with respect to the vertical at the time the ball was clamped can be determined by measuring the acute angle formed by the ball, shaft and detector(s) in their locked position and a surface known to be vertical when the seismometer is in the normal, up-right position it would assume on a flat, horizontal surface. The invention also comprises a method and apparatus for automatically leveling seismic motion detectors, when employed as the pendulum weight, for proper operation.
OBJECTS OF THE INVENTION
One object of the invention is to provide a simple and inexpensive method to determine the angle of inclination with respect to the vertical assumed by a recoverable device, such as a seismometer designed to operate on the ocean floor.
Another object of the invention is to provide a simple and inexpensive apparatus for preserving the orientation assumed by such a device so that its angle of inclination with respect to the vertical can later be determined.
Another object of the invention is to provide a mounting and clamp for a seismic motion detector which provide good acoustic coupling between the ocean bottom and the detector.
Another object of the invention is to provide a simple and inexpensive apparatus for self-leveling the seismic motion detectors used in a seismometer especially designed to operate on the ocean floor.
Another object of the invention is to provide an apparatus which both levels the seismic motion detectors carried in a seismometer especially designed to operate on the ocean floor and preserves the angle of inclination with respect to the vertical that the seismometer assumes during its operation.
BRIEF DESCRIPTION OF THE DRAWINGS
The previously stated features and objects of the present invention, as well as others, will appear more clearly upon reading the following description of the preferred embodiment of the invention depicted in the attached drawings, in which:
FIG. 1 is a view of the seismometer deployed on the sea-bottom;
FIG. 2 is a partially cross-sectioned view of the invention mounting a single geophone; and
FIG. 3 is a partially cross-sectioned view taken along line 2--2 of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, the on-bottom seismometer is of the type described in the aforementioned applications. Briefly, the major components of th OBS depicted in the FIG. 1 include a frame 101, floats 102, an instrument compartment 103 which is sealed, and a ballast tube 104. Power supplies can be carried in the instrument compartment 103, one or more of the floats 102 or both. An identical ballast tube 104 is mounted as the "rear" side of the seismometer viewed in FIG. 1. When the seismometer is deployed on the ocean-bottom, the ballast tubes 104 normally are submerged into the mud or silt of the sea floor. The ballast tubes 104 are rigidly mounted to the frame and provide good seismic coupling between the frame of the seismometer and the ocean bottom. The instrument compartment 103 is preferably mounted at the bottom of the frame 101 to improve the seismometer's stability during descent, ascent and operation. Mounted in this way the instrument compartment 103 will also be embedded when the seismometer comes to rest on a soft, muddy surface thereby improving the seismic coupling between it and the ocean floor. In accordance with one aspect of this invention, the seismic detector is mounted on the inside of the door 12 of the instrument compartment 103. In accordance with the invention, a rigid connection is provided between the detector and the frame 101 of the seismometer to provide a good acoutic path between the sea bottom and the detector.
An acoustic command unit 105 at the surface produces acoustic commands for the on-bottom seismometer. The commands are sensed by a hydrophone 106 mounted on the seismometer and wired to the instrument compartment 103. Such acoustic commands are used, for example, to trigger the clamping of the detector into position after deployment of the seismometer. Acoustic commands are also used to release the seismometer after recording is complete. A timer (not depicted) can alternatively be provided in the seismometer to trigger the clamping of the detector.
FIG. 2 and FIG. 3 depict the preferred embodiment of the invention employed in a seismometer such as that depicted in in FIG. 1. A geophone 1, having a center of gravity 9 and a vertical operating axis (not depicted), is connected by a collar 3 or other suitable means to the end of a shaft 4 protruding from a spherical ball 5 having a center 10. Suitable means such as threading (depicted in FIGS. 1 and 2), glueing, etc. (not shown) are used to affix the collar 3 to the end of the shaft 4. The spherical ball 5 rests in an annular seat 6 provided in a mounting plate 7. To provide symmetrical freedom of motion to the geophone 1 and shaft 4, the annular plane formed within the circumference of the annular seat 6 should be horizontal when the seismometer in which the invention is installed is placed on a flat, horizontal surface. (Hereinafter this orientation of the seismometer shall be referred to as its "normal, up-right position".) The annular seat 6 is provided with a beveled face 6a for improved contact with the surface of the spherical ball 5. The geophone 1, shaft 4, and spherical ball 5, supported in this manner, form a simple pendulum. As a result of this arrangement, a line 8 passing through the center of gravity 9 of the geophone 1 and the center 10 of the spherical ball 5 will be vertically aligned when the geophone 1 is allowed to hang freely at the end of the shaft 4. Ideally, the center of gravity 9 should be located along a line passing through the center 10 of the spherical ball 5 and the central longitudinal axis of the shaft 4, as the line 8 is depicted to run in FIG. 2, to more easily measure the angle assumed by the geophone 1 and shaft 4 when locked into operating position while the seismometer is pitched over, but this alignment is not required to proper operation of the invention. Leads 2 carry the electrical signals between the geophone 1 and appropriate processing and recording equipment (not shown). Geophones and comparable seismic motion detectors are available from a number of commercial sources and are well-known. In the alternative to the vertical geophone depicted in the figures, a horizontal-type seismic motion detector or several seismic motion detectors can be mounted at the end of the shaft 4. The manner of mounting the detectors directly to the end of the shaft 4 or on or in a frame (not depicted) for mounting to the shaft 4 and the arrangement of the detectors are matters of personal preference. The construction, mounting and operation of such detectors are well known to those familiar with seismometer construction. It is only necessary that each detector be mounted with its operating axis parallel (if a "vertical" motion detector) or perpendicular (if a "horizontal" motion detector) to the line 8. Preferably, the detectors should also be mounted in such a way that the line 8 which will pass through the center of gravity of the detector or assembly of detectors coincides with the line passing through the central longitudinal axis of the shaft 4, again for ease of measuring the angle of inclination. Suspended in this fashion, each detector will be automatically aligned with respect to the vertical for proper operation by the pendulum action of the invention.
A stop ring 11 is preferably provided in the mounting plate 7 to prevent damage to the seat 6 which might occur if it were allowed to be struck by the side wall of the shaft 4, during handling or placement of the seismometer mounting the invention. Preferably the centers of the open planar areas formed within the circumferences of the annular seat 6 and stop ring 11 should lie along the line 8 when the seismometer is in its normal, up-right position to assure symmetrical freedom of motion of the geophone 1 and shaft 4 perpendicular to the vertical. The positions of geophone 1 at its outer limits of travel with the stop ring 11 installed are depicted in phantom in both FIG. 2 and FIG. 3. Although a total arc of less than 90° is illustrated, the inner diameter of annular seat 6 could be increased to a small fraction of an inch less than the diameter of the spherical ball 5 and that of the stop ring 11 also increased to allow a total arc of movement greater than 90° but less than 180°. If so constructed this would allow the invention to operate properly until the seismometer is pitched over at almost 90° from its normal, up-right position.
The mounting plate 7 is affixed by suitable means inside the instrument compartment 103 to the planar surface of its door 12. The door 12, which pivots around a vertical axis, is an ideal surface on which to mount the detector as it offers easy access to "cock" a plunger 30 for operation, as will be later described, and simplifies measuring the angle assumed by the geophone 1 and shaft 4 when clamped. The mounting plate 7 is designed to prevent the geophone 1 from striking other surfaces including the inner surface of the door 12. (See FIG. 3). If the invention is used to level one or more seismic motion detectors, the seismometer and enclosure are constructed of suitable materials and in such a way that seismic vibrations are transmitted without significant dampening or filtering from the ocean floor on which the seismometer lies to the surface of the door 12 supporting the invention. Similarly, the means by which the mounting plate 7 is attached to the door 12 and the material from which the mounting plate 7, annular seat 6, spherical ball 5, shaft 4, and collar 3 are constructed are suitable to transmit seismic vibrations without dampening or filtering to the geophone 1. Those knowledgeable with seismometer construction will be familiar with the variety of materials and techniques available to them for constructing the invention.
As depicted in FIGS. 2 and 3, the mounting plate 7 is adapted to receive a plunger shaft 30b which is the central body of the plunger 30. A head 31 is mounted by suitable means, such as a clevis 32, to the end of the plunger shaft 30b closest to the spherical ball 5. The plunger 30 should be positioned on the mounting plate 7 in such a way that when the plunger 30 is extended, its head 31 comes into sufficient contact with the surface of the spherical ball 5 so as to lock the spherical ball 5, shaft 4 and geophone 1 in their assumed orientation. Preferably, the plunger 30 should also be positioned so that a line extending through the central longitudinal axis of the plunger shaft 30b also passes through the center 10 of the spherical ball 5 and the center of the open planar area formed within the circumference of the annular seat 6. This will reduce the likelihood of the plunger 30 imparting a torsional force to the spherical ball 5 when striking it, disturbing the position of the shaft 4 and cylinder 1. The head 31 should be constructed of synthetic rubber of other material suitable to cushion the impact of the plunger 30 when it strikes the surface of the spherical ball 5 so as not to disturb its position or that of the geophone 1 and to grip the surface of the spherical ball 5 so that it does not subsequently rotate. Although not required for proper operation of the invention, the end of the plunger 30 opposite the head 31 is preferably shaped into a handle 30a allowing that end of the plunger to be more easily gripped.
A coil spring 33 is positioned around the plunger shaft 30b. Suitable surfaces such as an overhand 31a of the head 31 and a surface 7a of the mounting plate 7 are provided as a means for compressing the coil spring 33. The coil spring 33 must be selected so as to remain in a sufficiently compressed state when the plunger 30 is fully extended to assure that sufficient forces are imparted by the head 31 to the spherical ball 5 to prevent its further motion or rotation and to further assure that the spherical ball 5 is firmly pressed against the annular seat 6 so as to provide an adequate path for seismic vibrations from the annular seat 6 to the geophone 1.
A first bore 13 is provided in the mounting plate 7 to allow the passage of a pin 15. A second bore 14 is provided in the plunger shaft 30b to receive the pin 15. The purpose of the pin 15 is to restrain the plunger 30 away from the surface of the spherical ball 5 and the first bore 13 and second bore 14 must be suitably located to accomplish this when the pin 15 is positioned within them.
A solenoid 16 is provided as a means for removing the pin 15. The solenoid 16 is mounted to the mounting plate 7 or some other suitable surface by screws 16b or suitable means. A power source (not depicted) supplies electric current through a set of solenoid leads 16a to activate the solenoid 16. The solenoid 16 in FIG. 2 is depicted as having a linearly acting shaft 17 connected by a clevis 18 or other suitable means to an end of the pin 15. This mechanical linkage enables the pin 15 to be removed from the bore 14 in the plunger shaft 30b by the solenoid 16 when the latter is activated. Solenoids equipped with linearly acting shafts are available from a variety of commercial sources and their operation is well-known. Alternatively, any other device which can be activated to produce a linear stroke action adequate to remove the pin 15 from the plunger shaft 30b could be used in place of the solenoid 16 and linearly acting shaft 17.
In the preferred embodiment of the invention depicted in FIG. 2, a second coil spring 19 is positioned around the linearly acting shaft 17. A second plate 20, attached by screws 20a or other suitable means to the mounting plate 7 is provided as a surface against which the second coil spring 19 may be compressed. A face of the solenoid 16 may prove to be adequate for this purpose. The clevis 18 at the end of the pin 15 provides a suitable second surface against which the second coil spring 19 may be compressed. The purpose of the second coil spring 19 is to push the pin 15 to the left, as viewed in FIG. 2, to engage the second bore 14 when the first bore 13 and second bore 14 are aligned.
The operation of the invention is as follows. Before deploying the seismometer carrying the invention, the plunger 30 is cocked for operation by lifting it by its handle 30a and rotating it until the first bore 13 and second bore 14 align. At that point the second coil spring 19 in compression, forces the pin 15 to the left (as viewed in FIG. 2) causing the pin 15 to pass into the second bore 14 and engage the plunger shaft 30b restraining the head 31 from contacting the surface of the spherical ball 5. The seismometer carrying the invention is then deployed for operation as shown in FIG. 1. Once the unit is deployed, the line 8 passing through the center of gravity 9 of the geophone 1 (which is free to swing at the end of the shaft 4) and the center 10 of the spherical ball 5 is immediately and automatically aligned with respect to the vertical by the pendulum action of the invention. The geophone 1, which has been mounted with its vertical operating axis parallel to the line 8, is now positioned for proper operation. After the seismometer has been given an adequate amount of time to stabilize, an electric current is introduced from a power source (not shown) through the solenoid leads 16a activating the solenoid 16 causing the linearly acting shaft 17 to be moved to the right (as viewed in FIG. 2) withdrawing the pin 15 from the second bore 14. The coil spring 33 in compression forces the head 31 of the plunger 30 into contact with the surface of the spherical ball 5 locking it, the shaft 4 and the geophone 1 in their assumed positions. The acute angle formed by the line 8 when the geophone 1 is in its clamped position and in the position it assumes when hanging freely in the seismometer in the latter's normal, up-right position is the angle of inclination assumed by the seismometer. If the line 8 passes through the central longitudinal axis of the shaft 4, the angle of inclination can be determined by measuring the acute angle between the longitudinal side wall of the shaft and a surface, such as the door 12 or one of the walls of the instrument housing 103, known to be vertical when the seismometer is in its normal, up-right position.
Not included as part of the invention and heretofore omitted from this description has been the means by which the current to activate the solenoid 16 is controlled. Several methods, such as internal timers and acoustic signals can be used with on-bottom seismometers to activate switches. For example, a system which can be used for controlling the supply of electrical power to the solenoid 16 is described in the related U.S. application Ser. No. 163,757, filed June 27, 1980, "On-Bottom Seismometer Electronic System", Bowden et al. It is expected the user will select a method for activating the solenoid 16 or other device provided to remove the pin 15 from the plunger 30 which is most compatible with the other features of his seismometer.
Although the principles of the present invention have been described above in relation to a preferred embodiment, it must be understood that the description is only made by way of example and does not limit the scope of the invention. | A geophone is hung from a ball bearing in a pendular fashion so that it is free to swing in any direction. Because it is weighted, it will assume the correct positioning for operation. A clamp, carried with the pendular geophone in a seismometer designed for use on the ocean floor, fixes the geophone in a rigid position when a solenoid is actuated. After the seismometer is deployed on the sea bottom, it is desired to clamp the geophone into its assumed position. The solenoid is fired upon command causing the ball to be clamped. When the seismometer is recovered the angle of inclination with respect to the vertical it assumed at the time when the geophone was clamped can be determined by measuring the angle formed by the clamped geophone and a surface known to be vertical when the seismometer rests on a flat, horizontal surface. | 8 |
FIELD OF THE INVENTION
[0001] The invention relates to a method for drying painted workpieces. The invention additionally relates to a device for drying painted workpieces.
STATE OF THE ART
[0002] Drying devices, for drying painted workpieces, are known from the state of the art. A great multiplicity of such methods and arrangements have long been used in a number of branches of industry.
[0003] Whereas, in the field of industry, the freshly painted workpieces are hardened in drying channels by means of UV light and hot air, the craft sector uses mainly passive drying systems. The painted parts remain in the surface region until they have hardened to such an extent that they can undergo further processing. Rack trucks, for example, are known from the state of the art for storing the freshly treated parts. These trucks usually have a scissors-type connection, to enable the spacing of the supports to be adapted to the length of the workpieces. The workpieces on the rack trucks are moved for drying into drying chambers, where they remain until completely dried.
[0004] DE 10 2010 012 173 B3 describes a device for drying objects, in particular painted vehicle bodies, which comprises a drying tunnel. A painted workpiece is dried in the drying tunnel.
[0005] The drying tunnels known from the state of the art have the disadvantage that, for the painted workpieces, only a certain retention time is planned for drying. In the drying process, the painted workpieces pass through a drying tunnel in a predefined period of time. In this drying tunnel, therefore, it is not possible for the painted workpieces to be dried for differing periods of time, i.e. flexible drying times are not possible.
OBJECT OF THE INVENTION
[0006] The object of the present invention is to rectify the disadvantages of the state of the art. Consequently, it is an object of the present invention to provide a device and a method for drying, in particular for drying painted workpieces, in which flexible drying times can be achieved. A further object of the invention is to leave the workpieces to rest in the drying device, i.e. the workpieces are not subjected to any movement, during the retention time.
Description of the Invention
[0007] The object is achieved by the independent claims. Advantageous developments are defined in the dependent claims.
[0008] For the purpose of achieving the object, the present invention proposes a drying device, in particular for drying painted workpieces, which has at least two drying units, wherein the individual drying unit is set up to receive a number of painted workpieces, and heating means, which are set up to generate a constant temperature in the drying device and in each of the drying units.
[0009] The drying device is preferably designed as a tower or drying tower. The drying device is used for drying painted workpieces. The drying device has at least two drying units, in which the workpieces that are to be dried can be inserted and dried. The drying device may also be a flash-off device, a fume device or a tempering device.
[0010] The term drying is to be understood to include any type of cross-linking, polymerization and hardening of material, in particular the hardening of a paint by radiation. A high surface quality, and therefore a uniformly smooth flow of the paint, is to be achieved in this case.
[0011] The operation of drying the painted workpieces in the drying units of the drying device is preferably performed at 80° C. Correspondingly different temperatures for drying painted workpieces are then selected if paints require a higher or lower temperature for drying on a workpiece.
[0012] The operation of flashing-off the painted workpieces is preferably performed at room temperature in the flash-off device. During the flashing-off operation, the volatile components of a paint applied to a workpiece evaporate.
[0013] During tempering, a material is heated over a longer period of time. Such a method makes it possible, for example, to control the distribution of mechanical stresses in a component. Tempering makes it possible to selectively alter the structure and physical properties of a solid, for example the structure in the case of workpieces made of metal. It is thus possible to control the ageing process or a distress effect of a workpiece.
[0014] The painted workpieces are preferably painted metal sheets, in particular parts from automobile construction, and painted objects made of wood, plastic, porcelain or ceramic, etc.
[0015] A number of painted workpieces are preferably a multiplicity of painted workpieces that can be delivered on a workpiece carrier system, a pallet or other device, and jointly inserted in a drying unit.
[0016] The at least two drying units are dimensioned such that individual workpieces or a certain number of workpieces (for example, on a workpiece carrier system) can be received, and can be dried in the drying unit.
[0017] The drying units are preferably realized as chambers, or drying chambers, which are dimensioned accordingly for drying workpieces.
[0018] The heating means are provided as a heat source for drying the painted workpieces. Such heating means generate, for example, medium-wave or longwave infrared radiation or UV light. Drying can also be effected through the supply of hot air. The heating means are arranged centrally in the drying device, such that each drying unit can be heated to a predefined temperature. A predefined, constant temperature, at which the number of painted workpieces are to be dried, thus ensues in each of the drying units and in the drying device as a whole. In addition to the temperature, the air humidity inside the drying device, and the supply and composition of a gas, can be set.
[0019] During drying, a warm airflow is generated in the corresponding drying unit. During the drying phase, the airflow flows in the horizontal and/or vertical direction in the individual chambers.
[0020] Preferably, the individual chambers have perforated floors, which enable air to flow from chamber to chamber in the drying device. Consequently, in addition to the above-mentioned airflows in the individual chambers of the drying device, which has, for example, drying units arranged above one another, there is vertical airflow from chamber to chamber.
[0021] In a preferred design of the drying device according to the invention, the drying units can be loaded with workpieces independently of each other.
[0022] A first number of painted workpieces is inserted in a correspondingly first drying unit, such that the first drying unit can be loaded with workpieces. A second number of painted workpieces is inserted in a correspondingly second drying unit, such that the second drying unit can also be loaded with workpieces, independently of the first drying unit.
[0023] In a further preferred design of the drying device according to the invention, the drying units have at least one opening, which is set up as an inlet and/or outlet for the workpieces to be dried.
[0024] The openings are closable openings such as, for example, flaps. However, sluices may be provided for closing the openings. The openings must be closable, so that the same constant temperature prevails in the drying units inside the drying device. A supply of air from outside the drying device can thus be prevented.
[0025] In a further preferred design of the drying device according to the invention, the drying device has at least one distributing device, wherein the workpieces can be inserted in and/or removed from the drying units by means of the distributing device.
[0026] The distributing device is designed, on the one hand, to load the drying units of the drying device with painted workpieces. On the other hand, the distributing device is designed to convey the dried workpieces (after completion of drying) back out of the corresponding drying unit.
[0027] In a further preferred design of the drying device according to the invention, the distributing device has a lifting device and a conveying device.
[0028] The lifting device is mounted in a displaceable manner on the distributing device. Displacement of the lifting device is effected vertically along the distributing device, and corresponds to an upward and downward movement of the lifting device. The lifting device additionally has a conveying device. The lifting device lifts the workpieces to the height at which there is a free drying unit to receive the workpieces in the drying device. The workpieces can then be inserted in and/or removed from the drying units by means of the distributing device.
[0029] In a further preferred design of the drying device according to the invention, the dimensions of the drying unit are selected to receive a workpiece carrier system.
[0030] The number of workpieces can be inserted, on a workpiece carrier system, in the drying unit. The workpiece carrier system is, for example, a transport unit for receiving the multiplicity of workpieces, or for receiving only one workpiece. The workpiece carrier system may also be, for example, a band conveyor, mesh conveyor, steel conveyor, belt conveyor or roller conveyor. The conveying device, as described above, may also be realized as a workpiece carrier system.
[0031] In a further preferred design of the drying device according to the invention, the distributing device has a lifting device and/or a shift device.
[0032] Whereas, the lifting device, as described above, can only execute a vertical upward and downward movement along the distributing device, the shift device executes a horizontal movement of the distributing device.
[0033] In a further preferred design of the drying device according to the invention, the drying units are arranged vertically above one another and/or vertically next to one another.
[0034] It is thus possible for a multiplicity of drying units, which are next to one another and above one another, to be loaded with workpieces.
[0035] In a further preferred design of the drying device according to the invention, the drying device has a control unit for controlling the distributing device. The control unit is set to insert the workpieces in a free drying unit in the drying device and to remove the workpieces from the drying device.
[0036] Furthermore, the control unit has a timer, a memory and a processor, for determining the retention time of the workpieces in respectively one of the drying units.
[0037] The timer is used to measure the period of time over which the workpiece to be dried has already been drying in the drying device. The memory stores all information, for example which paint is to be dried on which workpiece, how long the workpieces have already been drying in the drying unit, and how much longer the drying operation will take in which of the drying units. The processor calculates when the workpieces can be removed, fully dried, from the device. The control unit detects whether there is a free drying unit available in the drying device. If a free drying unit is found, the workpiece is inserted in the free drying unit by means of the distributing device, controlled by the control device. As mentioned above, the control unit determines how long a workpiece has to dry at a constant temperature. Following completion of the drying operation, the dried workpiece is removed from the drying unit by means of the controlled distributing device.
[0038] In a further embodiment example of the present invention, further drying devices are provided, which can be accessed by means of a distributing device and a shift device.
[0039] By means of the shift device, the distributing device, together with the lifting device and the conveying device, can be displaced horizontally. Further drying devices, arranged horizontally next to one another, can be accessed, which drying devices, for example, all have the same temperature T 1 in the drying units, as previously described.
[0040] Also provided, however, are drying devices that, unlike the drying devices described above, have a different temperature, T 2 , for drying the workpieces, wherein here, likewise, the temperature T 2 is constant in the drying units.
[0041] For the purpose of achieving the object, the present invention proposes a method for drying, in particular for drying painted workpieces, comprising the following steps: receiving a first number of painted workpieces in a drying unit of a drying device, drying the first number of painted workpieces in the first drying unit at a constant temperature T, receiving at least one second number of painted workpieces in a further drying unit of the drying device, drying the at least second number of painted workpieces in the further drying unit at a constant temperature T, removing the first number of painted workpieces from the respective drying unit after a drying time t 1 , and removing the second number of painted workpieces from the second drying unit after a drying time t 2 .
[0042] In the case of a constant temperature T in the drying device, the first and the second number of workpieces can be dried independently of each other in respect of time. Accordingly, the first number of workpieces can be removed from the drying device, for example, after a time t 1 , and the second number of workpieces can be removed after a time t 2 . Moreover, a further number of workpieces t 3 -ti can be dried in the drying device, independently of each other in respect of time, at a constant temperature T.
[0043] A further preferred design of the method according to the invention for drying provides drying of painted workpieces in at least one second drying device at a constant temperature T 2 .
[0044] In the case of a constant temperature T 2 in the second drying device, the first and the second number of workpieces can be dried independently of each other in respect of time. Accordingly, the first number of workpieces can be removed from the second drying device, for example, after a time t 1 , and the second number of workpieces can be removed after a time t 2 . Moreover, a further number of workpieces t 3 -ti can be dried in the second drying device, independently of each other in respect of time, at a constant temperature T.
BRIEF DESCRIPTION OF THE FIGURES
[0045] FIG. 1 shows a first schematic view of the drying device according to the invention, wherein a first number of painted workpieces is located on a conveying device.
[0046] FIG. 2 shows a second schematic view of the drying device according to the invention, wherein the first number of painted workpieces is located on a lifting device.
[0047] FIG. 3 shows a third schematic view of the drying device according to the invention, wherein the first number of painted workpieces is located in a drying unit.
[0048] FIG. 4 shows a fourth schematic view of the drying device according to the invention, wherein a second number of painted workpieces is being removed from the drying unit.
[0049] FIG. 5 shows a plan view of the drying device according to the invention from FIGS. 1-4 .
[0050] FIG. 6 shows an alternative embodiment of FIG. 5 .
[0051] FIG. 7 shows an alternative embodiment, as compared with FIGS. 1-6 .
[0052] FIG. 8 shows a plan view of the drying device according to the invention from FIG. 7 .
DESCRIPTION OF PREFERRED EMBODIMENTS
[0053] FIG. 1 shows a conveying device 8 , which extends from the painting device 10 to a distributing device 3 .
[0054] Mounted on the distributing device 3 there is a lifting device 4 , which can be displaced vertically upwards, along the distributing device 3 . The lifting device 4 has a conveying device 5 . The conveying device 5 is provided on the lifting device 4 .
[0055] The end of the conveying device 5 that faces away from the lifting device 4 is connected to a drying device 1 .
[0056] The drying device 1 according to the invention is composed of a multiplicity of drying units 2 . 1 to 2 . 15 arranged above one another. For reasons of clarity, not all drying units are denoted individually.
[0057] The drying device 1 additionally has a control unit 12 . The distributing device 3 and the drying device 1 can be controlled by the control unit. The painted workpieces 6 . 1 can be inserted in a free drying unit 2 of the drying device 1 , and the dried workpieces 6 . 1 can be removed from the drying device 1 , by means of the control unit 12 .
[0058] A number of painted workpieces 6 . 1 , which have left the painting device 10 , are located on the conveying device 8 , on the way to the distributing device 3 (arrow A). The workpieces are then placed on the lifting device 4 of the distributing device 3 , in order to be conveyed vertically upwards along the distributing device (arrow B) as represented in FIG. 2 . The lifting device 4 conveys the workpieces up to a height at which there is a free drying unit 2 . 6 available to receive the workpieces 6 . 1 .
[0059] FIG. 2 shows the vertical displacement of the lifting device 4 along the distributing device 3 (arrow B). The original position of the lifting device 4 and of the conveying device from FIG. 1 is represented by a broken line.
[0060] Each drying unit 2 . 1 to 2 . 15 has an opening 7 , which is provided with a flap, in order to prevent the supply of air from outside the drying device 1 . The opening 7 is located on the side of the drying unit from which the workpieces are inserted and removed. For reasons of clarity, only one opening 7 is represented.
[0061] The workpieces to be dried 6 . 1 are located on the conveying device 5 , on the way to the drying device 1 (arrow C).
[0062] As represented in FIG. 3 , the flap 7 has been lifted up. The drying unit 2 . 6 is prepared for the insertion of the workpieces 6 . 1 . The conveying device 5 conveys the workpieces 6 . 1 into the free drying unit 2 . 6 . After the workpieces 6 . 1 have been inserted, the flap 7 is closed again. The drying operation is performed at a constant temperature in the drying device 1 as a whole, in the drying unit 2 . 6 .
[0063] FIG. 4 shows further workpieces 6 . 2 , etc., which have likewise been inserted in further drying units 2 . 4 , etc. in the drying device 1 , for the drying operation at constant temperature. In FIG. 4 , the drying time for the workpieces 6 . 2 has ended, such that the workpieces 6 . 2 can be removed from the drying unit 2 . 4 . Since the drying of the workpieces 6 . 2 is effected independently of the drying of the workpieces 6 . 1 , etc. in respect of time, the drying of the workpieces 6 . 1 , etc. is not complete in this case. The flap 7 is opened in order to remove the dried workpieces 6 . 2 from the drying unit 2 . 4 . The workpieces 6 . 2 are removed in the direction of the arrow D. The conveying device 5 removes the workpieces 6 . 2 from the drying unit 2 . 4 in the direction of the distributing device 3 .
[0064] As represented in the plan view in FIG. 5 , the workpieces 6 . 2 can be transported away by means of a conveying device 9 . For this purpose, the lifting device 4 must first be lowered, with the workpieces 6 . 2 , to the level of the conveying device 9 .
[0065] Provided in FIG. 5 are further drying devices 1 . 1 to 1 . 4 , arranged horizontally next to one another, which all have the same temperature in the drying units (for example, 60° C.)
[0066] FIG. 5 additionally shows a shift device 11 . By means of the shift device 11 , the distributing device 3 , together with the lifting device 4 and the conveying device 5 , can be displaced horizontally (arrow E). Painted workpieces can be inserted in one of the free drying units of the drying devices 1 . 1 to 1 . 4 . After completion of drying, the workpieces can be transported away via the conveying device 9 .
[0067] Like FIG. 5 , FIG. 6 shows a shift device 11 . By means of the shift device 11 , the distributing device 3 , together with the lifting device 4 and the conveying device 5 , can be displaced horizontally (arrow E). In FIG. 6 , further drying devices, arranged horizontally next to one another, are provided in addition to the drying devices 1 . 1 to 1 . 4 . For reasons of clarity, not all drying devices are denoted individually. The further drying devices have, in the respective drying units, temperatures that differ from those of the drying devices 1 . 1 to 1 . 4 (for example, 25° C., 45° C., 60° C. and 80° C.). For reasons of clarity, not all drying devices are denoted individually.
[0068] FIG. 7 shows an alternative embodiment, as compared with FIGS. 1 to 6 . Unlike FIG. 4 , after the drying time for the materials has been completed, the flap 7 ′, not the flap 7 , is opened, in order to remove the dried workpieces from the drying unit. The flap 7 ′ is arranged on the side opposite the flap 7 .
[0069] In FIG. 7 , the workpieces 6 . 1 are removed in the direction of the arrow D. The conveying device 5 ′ transports the workpieces 6 . 1 , in the direction of the distributing device 3 ′, on to the lifting device 4 ′. The lifting device 4 is lowered to the level of the conveying device 9 ′. The workpieces 6 . 1 can be transported away via the conveying device 9 ′.
[0070] Unlike FIG. 6 , FIG. 8 shows a further shift device 11 ′. By means of the shift device 11 ′, the distributing device 3 ′, together with the lifting device 4 ′ and the conveying device 5 ′, can be displaced horizontally (arrow E′). It is thereby possible to remove dried workpieces from the drying device 1 and to deliver them to the conveying device 9 ′ (arrow F′). As in FIG. 6 , further drying devices, arranged horizontally next to one another, are provided in addition to the drying devices 1 . 1 to 1 . 4 . For reasons of clarity, not all drying devices are denoted individually. The further drying devices have, in the respective drying units, temperatures that differ from those of the drying devices 1 . 1 to 1 . 4 (for example, 25° C., 45° C., 60° C. and 80° C.). For reasons of clarity, not all drying devices are denoted individually.
[0071] The invention provides a device and a method for drying, in particular for drying painted workpieces, in which flexible drying times can be achieved and in which the workpieces can rest during the retention time in the drying device.
LIST OF REFERENCES
[0000]
1 drying device
2 drying unit
3 distributing device
4 lifting device
5 conveying device
6 workpiece
7 closure
8 conveying device
9 conveying device
10 painting device
11 shift device
12 control device
13 opening | The present invention relates to a method and a device for drying, in particular for drying painted workpieces ( 6 ), which has at least two drying units ( 2 ), wherein the individual drying unit is set up to receive a number of painted workpieces, and heating means, which are set up to generate a constant temperature in the drying device ( 1 ) and in each of the drying units ( 2 ). | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 09/586,648, filed on Jun. 1, 2000 which is a continuation-in-part of patent application Ser. No. 09/286,650 filed Apr. 6, 1999, entitled “Method and Apparatus For Determining Position in a Pipe”, now U.S. Pat. No. 6,333,699, which claims the benefit of U.S. Provisional Patent Application Ser. No. 60/098,284, filed on Aug. 28, 1998, now abandoned.
This application is related to the following copending patent applications: U.S. patent application Ser. No. 09/656,720, filed on Sept. 7, 2000 and entitled “Method and System for Performing a Casing Conveyed Perforating Process and Other Operations in Wells”; U.S. patent application Ser. No. 09/843,998, filed on Apr. 27, 2001 and entitled “Process and Assembly for Identifying and Tracking Assets”; and U.S. patent application Ser. No. 10/032,114, filed on Dec. 21, 2001 and entitled “Method and Apparatus for Determining Position in a Pipe”.
FIELD OF THE INVENTION
This invention relates to generally to wells used in the production of fluids such as oil and gas. More specifically, this invention relates to a method and system for performing various operations and for improving production in wells.
BACKGROUND OF THE INVENTION
Different operations are performed during the drilling and completion of a subterranean well, and also during the production of fluids from subterranean formations via the completed well. For example, different downhole operations are typically performed at some depth within the well, but are controlled at the surface.
A perforating process is one type of downhole operation that is used to perforate a well casing. A conventional perforating process is performed by placing a perforating tool (i.e., perforating gun) in a well casing, along a section of the casing proximate to a geological formation of interest. The perforating tool carries shaped charges that are detonated using a signal transmitted from the surface to the charges. Detonation of the charges creates openings in the casing and concrete around the casing, which are then used to establish fluid communication between the geological formation, and the inside diameter of the casing.
Another example of a downhole operation is the setting of packers within the well casing to isolate a particular section of the well or a particular geological formation. In this case, a packer can be placed within the well casing at a desired depth, and then set by a setting tool actuated from the surface. Other exemplary downhole operations include the placement of logging tools at a particular geological formation or depth within the well casing, and the placement of bridge plugs, casing patches, tubulars, and associated tools in the well casing.
One critical aspect of any downhole operation involves ascertaining the depth in the well where the operation is to be performed. The depth is typically ascertained using well logs. A conventional well log includes continuous readings from a logging instrument, and an axis which represents the well depths at which the readings were obtained. The instrument readings measure rock characteristics such as natural gamma ray radiation, electrical resistivity, density and acoustic properties. Using these rock characteristics geological formations of interest within the well, such as oil and gas bearing formations, can be identified. The well is initially logged “open hole” which becomes the bench mark for all future logs. After the well is cased, a cased hole log is then prepared and correlated, or “tied in”, to the open hole log.
Using the logs and a positioning mechanism, such as a wire line or coiled tubing, coupled to an odometer, a tool can be placed at a desired depth within the well, and then actuated as required to perform the downhole operation. One problem with conventional logging and positioning techniques is that it is difficult to accurately identify the depth of the tool, and to correlate the depth to the open hole logs.
FIG. 1 illustrates a prior art perforating process being performed in an oil and gas well 10 . The well 10 includes a well bore 12 , and a casing 14 within the well bore 12 surrounded by concrete 16 . The well 10 extends from an earthen surface 18 through geological formations within the earth, which are represented as Zones A, B and C. The casing 14 is formed by tubular elements, such as pipe or tubing sections, connected to one another by collars 20 . In this example the tubular elements that form the casing 14 are about 40 feet long so that the casing collars 20 are forty feet apart. However, tubular elements with shorter lengths (e.g., twenty feet) can be interspersed with the forty feet lengths to aid in depth determinations. Thus in FIG. 1 two of the casing collars 20 are only twenty feet apart.
For performing the perforating operation a perforating tool 22 has been lowered into the casing 14 on a wire line 24 . A mast 26 and pulleys 28 support the wire line 24 , and a wire line unit 30 controls the wire line 24 . The wire line unit 30 includes a drive mechanism 32 that lowers the wire line 24 and the tool 22 into the well 10 , and raises the wire line 24 and the tool 22 out of the well 10 at the completion of the process. The wire line unit 30 also includes an odometer 34 that measures the unwound length of the wire line 24 as it is lowered into the well 10 , and equates this measurement to the depth of the tool 22 within the well.
During formation of the well 10 an open hole log 36 was prepared. The open hole log 36 includes various instrument readings, such as gamma ray readings 38 and spontaneous potential (SP) readings 40 which are plotted as a function of depth in feet. For simplicity only a portion of the open hole log 36 , from about 7000 feet to about 7220 feet, is illustrated. However, in actual practice the entire well 10 from the surface 18 to the bottom of the well 10 may be logged. The open hole log 36 permits skilled artisans to ascertain the oil and gas containing formations within the well 10 and the most productive intervals of those formations. For example, based on the gamma ray readings 38 and the SP readings 40 it is determined that Zone A may contain oil and gas reserves. It is thus desired to perforate the casing 14 along a section thereof proximate to Zone A.
In addition to the open hole log 36 , following casing of the well 10 , cased hole gamma ray readings 44 are made, and a casing collar log 42 can be prepared. The casing collar log 42 is also referred to as a PDC log (perforating depth control log). The casing collar log 42 can be used to identify the section of the casing 14 proximate to Zone A where the perforations are to be made.
Using techniques and equipment that are known in the art, the casing collar log 42 can be accurately correlated, or “tied in”, to the open hole log 36 . However, using conventional positioning mechanisms, such as the wire line unit 30 , it may be difficult to accurately place the perforating tool 22 at the required depth within the well. For example, factors such as stretching, elongation from thermal effects, sinusoidal and helical buckling, and deformation of the wire line 24 can affect the odometer readings, and the accuracy of the odometer readings relative to the open hole odometer readings.
Thus, as shown in FIG. 1 , the odometer readings which indicate the depth of the perforating tool 22 , may not equate to the actual depths, as reflected in the open hole log 36 and the casing collar log 42 . In this example, the odometer readings differ from the depths identified in the open hole log 36 and the casing collar log 42 by about 40 feet. With this situation, when the perforating tool 22 is fired, the section of casing 20 proximate to Zone A may be only partially perforated, or not perforated at all.
Because of these tool positioning inaccuracies, various correlative joint logging and wire logging techniques have been developed in the art. For example, one prior art technique uses electronic joint sensors, and electrically conductive wire line, to determine joint-to-joint lengths, and to correlate the odometer readings of the wire line to the casing collar log. Although these correlative joint logging and wire line logging techniques are accurate, they are expensive and time consuming. In particular, additional crews and surface equipment are required, and additional wire line footage charges are incurred.
In addition to tool positioning inaccuracies, computational errors also introduce inaccuracies in depth computations. For example, a tool operator can make computational errors by thinking one number (e.g., 7100), while the true number may be different (e.g., 7010). Also, the tool operator may position the tool by compensating a desired amount in the uphole direction, when in reality the downhole direction should have been used. These computational errors are compounded by fatigue, the weather, and communication problems at the well site.
It would be desirable to obtain accurate depth readings for downhole tools without the necessity for complicated and expensive correlative joint logging and wire logging techniques. In addition, it would be desirable to control down hole operations and processes without having to rely on inaccurate depth readings contaminated by computational errors. The present invention is directed to an improved method and system for performing operations and processes in wells, in which the depths of down hole tools are accurately ascertained and used to control the operations and processes.
Another limitation of conventional downhole operations that are dependent on depth measurements, is that downhole tools must first be positioned in the well, and then actuated from the surface. This requires additional time and effort from well crews. In addition, surface actuation introduces additional equipment and variables to the operations. It would be advantageous to be able to control downhole operations without the requirement of surface actuation of the downhole tools. With the present invention actuation of downhole tools can be performed in the well at the required depth.
SUMMARY OF THE INVENTION
In accordance with the present invention a method and a system for performing various operations in wells, and for improving production in wells, are provided. Exemplary operations that can be performed using the method include perforating processes, packer setting processes, bridge plug setting processes, logging processes, inspection processes, chemical treating processes, casing patch processes, jet cutting processes and cleaning processes. Each of these processes, when performed in a well according to the method, improves the well and improves production from the well.
In an illustrative embodiment the method is used to perform a perforating process in an oil or gas production well. The well includes a well bore, and a well casing, extending from an earthen or subsea surface into various geological zones within the earth. The well casing includes lengths of pipe or tubing joined together by casing collars.
The method includes the initial step of providing identification devices at spaced intervals along the length of the well casing. The identification devices can comprise active or passive radio identification devices installed in each casing collar of the well casing. Each radio identification device is uniquely identified, and its depth, or location, within the well is accurately ascertained by correlation to well logs. Similarly, each casing collar is uniquely identified by the radio identification device contained therein, and a record of the well including the depth of each casing collar and identification device is established.
The method also includes the step of providing a reader device, and a transport mechanism for moving the reader device through the well casing proximate to the identification devices. In the illustrative embodiment the reader device comprises a radio frequency transmitter and receiver configured to provide transmission signals for reception by the identification devices. The identification devices are configured to receive the transmission signals, and to transmit response signals back to the reader device. The transport mechanism for the reader device can comprise a wire line, tubulars, coil tubing, a robotic mechanism, a fluid transport mechanism such as a pump or a blower, a free fall arrangement, or a controlled fall arrangement such as a parachute.
In addition to transmitting and receiving signals from the identification devices, the reader device is also configured to transmit control signals for controlling a process tool, as a function of the response signals from the identification devices. For example, the reader device can control a perforating tool configured to perforate the well casing. Specifically, the reader device and the perforating tool can be transported together through the well casing past the identification devices. In addition, the reader device can be programmed to transmit the control signal to detonate the perforating tool, upon reception of a response signal from an identification device located at a predetermined depth or location within the well. Stated differently, the reader device can be programmed to control the perforating tool responsive to locating a specific identification device.
As other examples, the reader device can be configured to control setting tools for packers, bridge plugs or casing patches, to control instrument readings from logging tools, and to control jet cutters and similar tools. With the method of the invention the true depth of the process tool can be ascertained in real time by the reader device using response signals from the identification devices. Accordingly, there is no need to ascertain the depth of the tool using an odometer, and expensive wire logging techniques. In addition, operator computational errors are reduced because true depth readings can be provided without the requirement of additional computations. Further, for some processes, there is no need to transmit signals to the surface, as the reader device can be programmed to control the process in situ within the well.
However, it is to be understood that the method of the invention can also be practiced by transmission of the control signals from the reader device to a controller or computer at the surface, and control of the process tool by the controller or computer. In addition, control of the process tool can be performed dynamically as the process tool moves through the well with the reader device, or statically by stopping the process tool at a required depth. Further, the method of the invention can be used to control a multi stage process, or to control a tool configured to perform multiple processes. For example, a combination packer setting and perforating tool can be configured to perform packer setting and perforating processes, as a function of true depth readings obtained using the method of the invention.
In the illustrative embodiment the system includes the identification devices installed in casing collars at spaced intervals along the well casing. The identification devices include a programmable element, such as a transceiver chip for receiving and storing identification information, such as casing collar and depth designations. Each identification device can be configured as a passive device, an active device having an antenna, or a passive device which can be placed in an active state by transmission of signals through well fluids.
The system also includes the reader device and the process tool configured for transport through the well casing. In addition to the transmitter and receiver, the reader device includes one or more programmable memory devices, such as semiconductor chips configured to receive and store information. The reader device also includes a power source such as a power line to the surface, or a battery. In addition, the reader device includes a telemetry circuit for transmitting the control signals, which can be used to control the process tool, and to provide depth and other information to operators and equipment at the surface. The system can also include a computer configured to receive and process the control signals, and to provide and store information in visual or other form for well operators and equipment. Further, the system can include a controller configured to process the control signals for controlling the process tool and various process equipment. The controller can be located at the surface, or on the process tool, to provide a self contained system. Also, the system can be transported to a well site in the form of a kit, and then assembled at the well site.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a prior art downhole operation being performed using well logs and odometer readings from a tool positioning mechanism;
FIG. 2 is a flow diagram illustrating steps in the method of the invention for controlling a perforating process in a well;
FIGS. 3A and 3B are schematic cross sectional views illustrating a system constructed in accordance with the invention for performing the perforating process;
FIG. 3C is an enlarged portion of FIG. 3B , taken along section line 3 C, illustrating a perforating tool of the system;
FIG. 3D is an enlarged portion of FIG. 3A , taken along section line 3 D, illustrating a reader device and an identification device of the system;
FIG. 3E is an enlarged cross sectional view taken along section line 3 E of FIG. 3D illustrating a portion of the reader device;
FIG. 3F is a side elevation view of an alternate embodiment active reader device and threaded mounting device;
FIG. 4A is an electrical schematic for the system;
FIG. 4B is a view of a computer screen for a computer of the system;
FIGS. 5A and 5B are schematic views illustrating exemplary spacer elements for spacing the reader device of the system from the perforating tool of the system;
FIGS. 6A-6D are schematic cross sectional views illustrating various alternate embodiment transport mechanisms for the system;
FIGS. 7A and 7B are schematic cross sectional views illustrating an alternate embodiment system constructed in accordance with the invention for performing a packer setting process in a well;
FIG. 7C is an enlarged portion of FIG. 7A taken along section line 7 C illustrating a threaded connection of a tubing string of the alternate embodiment system; and
FIGS. 8A-8C are schematic cross sectional views illustrating an alternate embodiment multi stage method and system of the invention for performing a packer setting and a perforating processes in combination.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 2 , broad steps in a method for controlling an operation or process in a subterranean well in accordance with the invention are illustrated. The method, broadly stated, includes the steps of:
A. Providing a process tool. B. Providing a reader device in signal communication with the process tool. C. Providing a transport mechanism for the process tool and the reader device. D. Providing spaced identification devices in a well casing readable by the reader device. E. Uniquely identifying each identification device and determining its depth, or location, in the well using well logs. F. Programming the reader device to transmit a control signal to the process tool upon reception of a response signal from a selected identification device. G. Transporting the process tool and the reader device through the well casing. H. Reading the identification devices using the reader device. I. Transmitting the control signal to the process tool upon reception of the signal from the selected identification device to actuate the process tool at a selected depth.
Referring to FIGS. 3A-3D , a system 50 constructed in accordance with the invention is illustrated. The system 50 is installed in a subterranean well 52 , such as an oil and gas production well. In this embodiment the system 50 is configured to perform a perforating process in the well 52 . The perforating process performed in accordance with the invention provides an improved well 52 , and improves production from the well 52 .
The well 52 includes a well bore 54 , and a well casing 56 within the well bore 54 surrounded by concrete 56 . The well 52 extends from an earthen surface 60 through geological formations within the earth, which are represented as Zones E, F and G. The earthen surface 60 can be the ground, or alternately a structure, such as an oil platform located above water. In the illustrative embodiment, the well 52 extends generally vertically from the surface 60 through Zones E, F, and G. However, it is to be understood that the method can also be practiced on inclined wells, and on horizontal wells.
The well casing 56 comprises a plurality of tubular elements 62 , such as lengths of metal pipe or tubing, connected to one another by collars 64 . The casing 56 includes an inside diameter adapted to transmit fluids into, or out of, the well 52 , and an outside diameter surrounded by the concrete 58 . The collars 64 can comprise couplings having female threads adapted for mating engagement with male threads on the tubular elements 62 . Alternately, the collars 64 can comprise weldable couplings adapted for welding to the tubular elements 62 .
Also in the illustrative embodiment the casing 56 is illustrated as having the same outside diameter and inside diameter throughout its length. However, it is to be understood that the casing 56 can vary in size at different depths in the well 52 , as would occur by assembling tubulars with different diameters. For example, the casing 56 can comprise a telescoping structure in which the size thereof decreases with increasing depth.
Based on an open hole well log ( 36 - FIG. 1 ), or other information, it is determined that Zone F of the well 52 may contain oil and gas. It is thus desired to perforate the casing 56 proximate to Zone F to establish fluid communication between Zone F, and the inside diameter of the well casing 56 .
For performing the perforating process, the system 50 includes a perforating tool 68 , and a reader device 70 in signal communication with the perforating tool 68 . The system 50 also includes a plurality of identification devices 72 ( FIG. 3D ) attached to the collars 64 on the casing 56 , and readable by the reader device 70 . In addition, the system 50 includes a transport mechanism 66 W for transporting the perforating tool 68 and the reader device 70 through the well casing 56 to Zone F. If desired, the system 50 can be transported to the well 52 as a kit, and then assembled at the well 52 .
As shown in FIG. 3C , the perforating tool 68 includes a detonator 74 (illustrated schematically) and a detonator cord 76 in signal communication with the detonator 74 . The detonator 74 can comprise a commercially available impact or electrical detonator configured for actuation by a signal from the reader device 70 . Similarly, the detonator cord 76 can comprise a commercially available component. The detonator 74 and the detonator cord 76 are configured to generate and apply a threshold detonating energy to initiate a detonation sequence of the perforating tool 68 . In the illustrative embodiment, the detonator 74 is located on, or within, the perforating tool 68 .
As shown in FIG. 3C , the perforating tool 68 also includes one or more charge carriers 78 each of which comprises a plurality of charge assemblies 80 . The charge carriers 78 and charge assemblies 80 can be similar to, or constructed from, commercially available perforating guns. Upon detonation, each charge assembly 80 is adapted to blast an opening 82 through the casing 56 and the concrete 58 , and into the rock or other material that forms Zone F.
As shown in FIG. 3D , each collar 64 includes an identification device 72 . Each identification device 72 can be attached to a resilient o-ring 86 placed in a groove 84 within each collar 64 .
In the illustrative embodiment, the identification devices 72 comprise passive radio identification devices (PRIDs). PRIDs are commercially available and are widely used in applications such as to identify merchandise in retail stores, and books in libraries. The PRIDs include a circuit which is configured to resonate upon reception of radio frequency energy from a radio transmission of appropriate frequency and strength. Passive PRIDs do not require a power source, as the energy received from the transmission signal provides the power for the PRIDs to transmit a reply signal during reception of the transmission signal.
The identification device 72 includes an integrated circuit chip, such as a transceiver chip, having memory storage capabilities. The integrated circuit chip can be configured to receive RF signals and to encode and store data based on the signals. During a data encoding operation each identification device 72 can be uniquely identified such that each collar 64 is also uniquely identified. This identification information is indicated by the C 1 -C 8 designations in FIGS. 3A and 3B . In addition, the depth of each collar 64 can be ascertained using well logs, as previously explained and shown in FIG. 1 . The depth information can then be correlated to the identification information encoded into the identification device 72 . A record can thus be established identifying each collar 64 and its true depth in the well 52 .
Alternately, as shown in FIG. 3F , identification device 72 A can be in the form of an active device having a separate power source such as a battery. In addition, the identification device 72 A can include an antenna 89 for transmitting signals. Alternately, an identification device (not shown) can be configured to transmit signals through a well fluid or other transmission medium within the well 52 . Such an identification device is further described in previously cited parent application Ser. No. 09/286,650, which is incorporated herein by reference.
As also shown in FIG. 3F , the identification device 72 A can be contained in a threaded mounting device 87 . The threaded mounting device 87 can comprise a rigid, non-conductive material such as a plastic. The threaded mounting device 87 is configured to be screwed into the middle portions of the casing collar 64 ( FIG. 3D ), and to be retained between adjacent tubular elements of the casing 56 . The threaded mounting device 87 includes a circumferential groove 91 for the antenna 89 , and a recess 93 for the identification device 72 A. If desired, the antenna 89 and the identification device 72 A can be retained in the groove 91 and the recess 93 using an adhesive or a suitable fastener.
Referring to FIG. 3E , the reader device 70 is shown in greater detail. The reader device 70 is configured to transmit RF transmission signals at a selected frequency to the identification devices 72 , and to receive RF response signals from the identification devices 72 . As such, the reader device 70 includes a base member 77 having a transmitter 73 configured to transmit transmission signals of a first frequency to the identification devices 72 . The reader device 70 includes a receiver 71 on the base member 77 configured to receive signals of a second frequency from the identification devices 72 .
Preferably, the transmitter 73 is configured to provide relatively weak transmission signals such that only an identification device 72 within a close proximity (e.g., one foot) of the reader device 70 receives the transmission signals. Alternately, the antenna of the reader device 70 can be configured to provide highly directional transmission signals such that the transmission signals radiate essentially horizontally from the reader device 70 . Accordingly, the transmission signals from the reader device 70 are only received by a single identification device 72 as the reader devices passes in close proximity to the single identification device 72 .
In addition to the transmitter 73 and the receiver 71 , the reader device 70 includes a cover 79 made of an electrically non-conductive material, such as plastic or fiberglass. The reader device 70 also includes o-rings 75 on the base member 77 for sealing the cover 79 , and a cap member 81 attached to the base member 77 which secures the cover 79 on the base member 77 . In addition, the reader device 70 includes spacer elements 83 formed of an electrically non-conductive material such as ferrite, ceramic or plastic, which separate the transmitter 73 and the receiver 71 from the base member 77 . In the illustrative embodiment, the base member 77 is generally cylindrical in shape, and the spacer elements 83 comprise donuts with a half moon or contoured cross section.
Referring to FIG. 4A , an electrical schematic for the system 50 is illustrated. As illustrated schematically, each identification device 72 includes a memory device 110 , in the form of a programmable integrated circuit chip, such as a transceiver chip, configured to receive and store identification information. As previously explained, the identification information can uniquely identify each casing collar 64 with an alpha numerical, numerical or other designator. In addition, using previously prepared well logs, the depth of each uniquely identified casing collar 64 can be ascertained.
As also shown in FIG. 4A , the reader device 70 includes the transmitter 73 for transmitting transmission signals to the identification devices 72 , and the receiver 71 for receiving the response signals from the identification devices 72 . The reader device 70 can be powered by a suitable power source, such as a battery, or a power supply at the surface. In addition, the reader device 70 includes a memory device 112 , such as one or more integrated circuit chips, configured to receive and store programming information. The reader device 70 also includes a telemetry circuit 114 configured to transmit control signals in digital or other form, through software 116 to a controller 118 , or alternately to a computer 122 .
As is apparent the software 116 can be included in the controller 118 , or in the computer 122 . In addition, the computer 122 can comprise a portable device such as a lap top which can be pre-programmed and transported to the well site. Also, as will be further explained, the computer 122 can include a visual display for displaying information received from the reader device 70 . The controller 118 , or the computer 122 , interface with tool control circuitry 120 , which is configured to control the perforating tool 68 as required.
In the illustrative embodiment, the tool control circuitry 120 is in signal communication with the detonator 74 ( FIG. 3C ) of the perforating tool 68 . The tool control circuitry 120 can be located on the perforating tool 68 , on the reader device 70 , or at the surface. The reader device 70 is programmed to transmit control signals to the tool control circuitry 120 , as a function of response signals received from the identification devices 72 . For example, in the perforating process illustrated in FIGS. 3A and 3B , coupling C 4 is located proximate to the upper level, or entry point into Zone F. Since it is desired to actuate the perforating tool 68 while it is in Zone F, the reader device 70 can be programmed to transmit actuation control signals through the tool control circuitry 120 to the detonator 74 ( FIG. 3C ), when it passes coupling C 4 and receives response signals from the identification device 72 contained in coupling C 4 . Because coupling C 4 is uniquely identified by the identification device 72 contained therein, and the depth of coupling C 4 has been previously identified using well logs, the perforating process can be initiated in real time, as the perforating tool 68 passes coupling C 4 and enters the section of the well casing 56 proximate to Zone F.
However, in order to insure that the detonation sequence is initiated at the right time additional factors must be considered. For example, the perforating tool 68 and reader device 70 can be transported through the well casing 56 with a certain velocity (V). In addition, the reader device 70 requires a certain time period (T 1 ) to transmit transmission signals to the identification device 72 in coupling C 4 , and to receive response signals from the identification device 72 in coupling C 4 . In addition, a certain time period (T 2 ) is required for transmitting signals to the tool control circuitry 120 and to the detonator 74 ( FIG. 3C ). Further, the charge assemblies 80 require a certain time period (T 3 ) before detonation, explosion and perforation of the casing 56 occur. All of these factors can be considered in determining which identification device 72 in which casing 64 will be used to make the reader device 70 transmit actuation control signals through the tool control circuitry 120 to the detonator 74 ( FIG. 3C ).
In order to provide proper timing for the detonation sequence, the velocity (V) of the perforating tool 68 and the reader device 70 can be selected as required. In addition, as shown in FIGS. 5A and 5B , a spacer element 88 can be used to space the perforating tool 68 from the reader device 70 by a predetermined distance (D). As shown in FIG. 5A , the perforating tool 68 can be above the reader device 70 (i.e., closer to the surface 60 ), or alternately as shown in FIG. 5B can be below the reader device 70 (i.e., farther from the surface 60 ).
As an alternative to a dynamic detonation sequence, the perforating tool 68 can be stopped when the required depth is reached, and a static detonation sequence performed. For example, the reader device 70 can be programmed to send a signal for stopping the perforating tool 68 when it reaches coupling C 6 . In this case, the signal from the reader device 70 can be used to control the wire line unit 92 and stop the wire line 90 . The detonation and explosive sequence can then be initiated by signals from the tool control circuit 120 , with the perforating tool 68 in a static condition at the required depth.
As shown in FIG. 4B , signals from the reader device 70 can be used to generate a visual display 124 , such as a computer screen on the computer 122 , which is viewable by an operator at the surface. The visual display 124 is titled “True Depth Systems” and includes a power switch for enabling power to the reader device 70 and other system components. The visual display 124 also includes a “Depth Meter” that indicates the depth of the reader device 70 (or the perforating tool 68 ) within the well 52 . The visual display 124 also includes “Alarm Indicators” including a “Well Alarm Top” indicator, a “Well Alarm Bottom” indicator, and an “Explosive Device” indicator. The “Alarm Indicators” are similar to stop lights with green, yellow and red lights to indicate varying conditions.
The visual display 124 also includes “Power Indicators” including a “True Depth Reader” power indicator, a “True Depth Encoder” power indicator, and a “System Monitor” power indicator. In addition, the visual display 124 includes various “Digital Indicators”. For example, a “Line Speed” digital indicator indicates the speed at which the reader device 70 , and the perforating tool 68 , are being transported through the well casing 56 . An “Encoder Depth” digital indicator indicates the depth of each identification device 72 as the reader device 70 passes by the identification devices 72 . A “True Depth” indicator indicates the actual depth of the reader device 70 in real time as it is transported through the well casing 56 .
The visual display 124 also includes a “TDS ID” indicator that indicates an ID number for each identification device 72 . In addition, the visual display 124 includes a “TDS Description” indicator that further describes each identification device 72 (e.g., location in a specific component or zone). The visual display 124 also includes a “Time” indicator that can be used as a time drive (forward or backward) for demonstration or review purposes. Finally, the visual display 124 includes an “API Log” which indicates log information, such as gamma ray or SPE readings, from the previously described well logs, correlated to the “Digital Indicators” for depth.
Referring again to FIGS. 3A and 3B , in the embodiment illustrated therein, the transport mechanism 66 W includes a wire line 90 operable by a wire line unit 92 , substantially as previously explained and shown in FIG. 1 . The wire line 90 can comprise a slick line, an electric line, a braided line, or coil tubing. If the controller 118 , or the computer 122 , is located at the surface 60 , the wire line 90 can be used to establish signal communication between the reader device 70 and the controller 118 or the computer 122 .
Referring to FIGS. 6A-6D , alternate embodiment transport mechanisms for transporting the perforating tool 68 and the reader device 70 through the casing 56 are shown. In FIG. 6A , a transport mechanism 66 P comprises a pump for pumping a conveyance fluid through the inside diameter of the casing 56 . The pumped conveyance fluid then transports the perforating tool 68 and the reader device 70 through the casing 56 . In FIG. 6B , a transport mechanism 66 R comprises one or more robotic devices attached to the perforating tool 68 and the reader device 70 , and configured to transport the perforating tool 68 and the reader device 70 through the casing 56 . In FIG. 6C , a transport mechanism 66 G comprises gravity (G) such that the perforating tool 68 and the reader device 70 free fall through the casing 56 . The free fall can be through a well fluid within the casing 56 , or through air in the casing 56 . In FIG. 6D , a transport mechanism 66 PA includes a parachute which controls the rate of descent of the perforating tool 68 and the reader device 70 in the casing 56 . Again, the parachute can operate in a well fluid, or in air contained in the casing 56 .
Referring to FIGS. 7A-7C , an alternate embodiment system 50 A constructed in accordance with the invention is illustrated. The system 50 A is installed in a subterranean well 52 A, such as an oil and gas production well. In this embodiment the system 50 A is configured to perform a packer setting process in the well 52 A.
The well 52 A includes a well bore 54 A, and a well casing 56 A within the well bore 54 A surrounded by concrete 58 A. The well casing 56 A comprises a plurality of tubular elements 62 A, such as lengths of metal pipe or tubing, connected to one another by collars 64 A. The well 52 A extends from an earthen surface 60 A through geological formations within the earth, which are represented as Zones H and I.
For performing the packer setting process, the system 50 A includes a packer setting tool 68 A, an inflation device 98 A for the packer setting tool 68 A, and a reader device 70 A in signal communication with the packer setting tool 68 A. In this embodiment, the inflation device 98 A is located on the surface 60 A such that a wire, or other signal transmission medium must be provided between the packer setting tool 68 A and the inflation device 98 A. The packer setting tool 68 A can include an inflatable packer element designed for inflation by the inflation device 98 A and configured to sealingly engage the inside diameter of the casing 56 A. In FIG. 7B , the inflatable packer element of the packer setting tool 68 A has been inflated to seal the inside diameter of the casing 56 A proximate to Zone I.
The system 50 A also includes a plurality of identification devices 72 ( FIG. 3D ) attached to the collars 64 A on the casing 56 A, and readable by the reader device 70 A. In addition, the system 50 A includes a transport mechanism 66 A for transporting the packer setting tool 68 A and the reader device 70 A through the well casing 56 A to Zone I. In this embodiment, the transport mechanism 66 A comprises a tubing string formed by tubular elements 102 A. As shown in FIG. 7C , each tubular element 102 A includes a male tool joint 94 A on one end, and a female tool joint 96 A on an opposing end. This permits the tubular elements 102 A to be attached to one another to form the transport mechanism 66 A. In addition, the packer setting tool 68 A can include a central mandrel in fluid communication with the inside diameter of the transport mechanism 66 A.
The reader device 70 A is programmed to transmit a control signal to the inflation device 98 A upon actuation by a selected identification device 72 ( FIG. 3D ). For example, in the packer setting process illustrated in FIGS. 7A and 7B , coupling C 4 A is located proximate to the upper level, or entry point into Zone I. Since it is desired to inflate the inflatable packer element of the packer setting tool 68 A while it is proximate to Zone I, the reader device 70 A can be programmed to transmit the control signal to the inflation device 68 A when it reaches coupling C 4 A. In this embodiment a spacer element 88 A separates the packer setting tool 68 A and the reader device 70 A. In addition, the packer setting tool 68 A is located downhole relative to the reader device 70 A.
In order to insure that the packer setting sequence is initiated at the right time additional factors must be considered as previously explained. These factors can include the velocity (V) of the packer setting tool 68 A and the reader device 70 A, and the time required to inflate the inflatable packer element of the packer setting tool 68 A. Alternately, the packer setting tool 68 A can be stopped at a particular coupling (e.g., coupling C 5 A) and then inflated as required. In this case the reader device 70 A can be programmed to transmit the control signals to the visual display 124 ( FIG. 4B ) on the surface 60 A when the packer tool 68 A passes a coupling 64 A at the required depth. The operator can then control the inflation device 98 A to initiate inflation of the packer setting tool 68 A. Alternately the inflation sequence can be initiated automatically by the tool control circuit 120 ( FIG. 4A ).
In each of the described processes the method of the invention provides an improved well. For example, in the perforating process of FIGS. 3A and 3B , the well 52 can be perforated in the selected zone, or in a selected interval of the selected zone. Production from the well 52 is thus optimized and the well 52 is able to produce more fluids, particularly oil and gas.
Referring to FIGS. 8A-8C , a multi stage operation performed in accordance with the method of the invention is illustrated. Initially, as shown in FIG. 8A , a combination tool 130 is provided. The combination tool 134 includes a packer setting tool 132 and a perforating tool 134 , which function substantially as previously described for the packer setting tool 68 A ( FIG. 7B ), and the perforating tool 68 ( FIG. 3A ) previously described. In addition, the combination tool 134 includes the reader device 70 and the casing 56 includes identification devices 72 ( FIG. 3D ) substantially as previously described. As also shown in FIG. 8A , the combination tool 130 is transported through the casing 56 using the gravity transport mechanism 66 G. Alternately, any of the other previously described transport mechanisms can be employed.
Next, as shown in FIG. 8B , the packer setting tool 132 is actuated such that an inflatable packer element of the tool 132 seals the casing 56 at a desired depth. In this embodiment the packer setting tool 132 is a self contained unit, with an integral inflation source. As with the previously described embodiments, the reader device 70 provides control signals for controlling the packer setting tool 132 , and the packer setting process. For example, the inflatable packer element of the packer setting tool 132 can be inflated when the reader device 70 passes a selected coupling 64 , and receives a response signal from the identification device 72 contained within the selected coupling 64 . As also shown in FIG. 8B , the perforating tool 134 separates from the packer setting tool 132 and continues to free fall through the casing 56 .
Next, as shown in FIG. 8C , the perforating tool 132 is controlled such that detonation and explosive sequences are initiated substantially as previously described. Again the reader device 70 provides control signals, for controlling the perforating tool 132 to initiate the detonation and explosive sequences at the proper depth. As indicated by the dashed arrows in FIG. 8C explosion of the charge assemblies 80 ( FIG. 3C ) of the perforating tool 134 forms openings in the casing 58 and the concrete 58 .
Thus the invention provides a method and a system for performing various operations or processes in wells and for improving production from the wells. While the invention has been described with reference to certain preferred embodiments, as will be apparent to those skilled in the art, certain changes and modifications can be made without departing from the scope of the invention as defined by the following claims. | A method for performing operations and for improving production in a well includes the steps of: providing radio identification devices at known locations in the well, and providing a reader device configured to read the identification devices, and to control the operations responsive to signals from the identification devices. The method also includes the steps of providing a process tool, and transporting the process tool and the reader device through the well. The reader device is programmed to control the process tool upon reception of a response signal from a selected identification device. The method can be used to perform perforating processes, packer setting processes, bridge plug setting processes, logging processes, inspection processes, chemical treating processes, and cleaning processes. In addition, the method can be performed dynamically by controlling the tool as it moves through the well, or statically by stopping the tool at a particular location within the well. A system for performing the method includes the identification devices, the reader device, the process tool, and a computer or controller. In addition the identification devices can be placed in casing collars of the well and can be configured as passive devices or as active devices. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to manufacturing processes used to make spherical polyester particles. The process can be exactly adjusted to pick a mean particle size anywhere in the range of from 1 to 200 μm, and can produce particles of very narrow particle size distribution. Particles made by this process have utility in a variety of applications, including applications as powder coatings and as particles suitable for application for toners and use in high resolution electrophotography.
Polymer particles are traditionally prepared by subjecting resin and additive components to intense mixing in an extruder at a temperature above the softening point of the film-forming polymer and then, by means of a milling process bringing the resulting extrudate to a particle form. For applications in powder coating, for example, irregularly shaped powders of particle sizes ranging from 20 to 100 μm are typically achieved. For applications as toners in electrophotography, powders with a mean particle size of from 7 to 20 μm are typically achieved. The milling process to make particles such as this has a number of deficiencies:
1. It leads to powders of irregular structure and broad particle size distribution,
2. It routinely produces significant amounts of oversized and undersized particles (fines), which can result in significant material loss and process expense due to sieving,
3. The irregular shape of the particles plus the broad particle size distribution can lead to less than ideal flow and charge behavior of the particles.
4. There is added expense associated with production of a finished resin and, in a separate step, conducting a milling or other particle generating operation.
To make toner particles suitable for high resolution laser printers and copy machines, for example, 1200 dot per inch resolution, it is necessary to have a particle with a size of 5 μm to meet these resolution requirements. Existing milling technology will make particles of this size only with considerable effort and waste, and the processing and economic problems mentioned above with irregular particle structure and broad particle size distribution are exacerbated as the size of the particle is reduced.
The breadth of a particle size distribution is characterized using not only the parameter d 50 , for which just 50% of the particles are greater than or smaller than the value d 50 , but also two further parameters: d 10 designates the particle size for which 10% of the particles are smaller than this value. Correspondingly, d 90 designates the particle size for which 90% of the particles are finer than the value d 90 . To characterize the breadth of a particle size distribution it is usual to form a quotient which is referred to as the span and is calculated in accordance with the following formula: span=(d 90 −d 10 )/d 50 . The relationship is thus: the smaller the span the narrower the particle size distribution. A powder comprising spheres identical in size would have a span of 0. For milled powders with a mean particle size d 50 of 50 μm, for example, a span of 3-4 is typically obtained.
It is also desirable, on the basis of economic considerations, to have processes for the manufacture of polymer particles which start with either monomeric components or oligomeric components, in which the polymer and the powder are produced in one process step. A process such as this which would produce a powder with the desired average particle size (d 50 ) with a narrow particle size distribution would be of even greater advantage. Some of the advantages would be a reduction in manufacturing cost (via combination of the polymerization and powder production steps, a reduction in the amount of waste, improvement in process yield, reduction in process time and improvement in energy efficiency.
There have been no lack of efforts to develop alternative methods for powder production by means of new technologies without incurring the above mentioned disadvantages in proccessability. The aim is, in general, to prepare particles with a near-ideal spherical form, since such powders exhibit substantially more favorable flow behavior than the irregular milled powders. It has been attempted, for example, to prepare near-spherical particles by spraying polymer melts. The results presented in WO 92/00342 indicated, however, that this leads only to moderate success. The particles obtained by this technique, although having a smoother surface than milled powders, are still far removed from the ideal structure of the sphere.
Another method which has been investigated for the preparation of spherical particles is the spraying of polymers from a supercritical solution, as described, for example, in EP-A-0 661 091 or EP-A-0 792 999. This method too has substantial disadvantages. For example, in the cited applications it is stated that owing to the sudden evaporation of the supercritical “solvent”, a powder is obtained which has a porous structure. When these powders are employed to prepare films there is—in comparison with nonporous powders, an increased occurrence of bubble formation and thus of defects in the coating, since the porous structure means that a large amount of gas is trapped in the powder and must be removed in the process of film formation. The use of supercritical solvents, moreover is technically complex since. for example, it requires operation under high pressure.
A method of producing spherical particles which differs in its principle is to produce a dispersion. Physical laws dictate that, in a dispersion, the perfect spherical form is the preferred geometry of the particles obtained. There has therefore been no lack of attempts in the past to obtain polymer particles which can be used, for example, as binders in coating systems, by preparing them in dispersion. (Keith Barett, Dispersion Polymerization in Organic Media, John Wiley and Sons, London, 1975). GB-1 373 531, for example, describes the preparation of stable dispersions of polycondensation polymers, such as polyesters.
The possibility of using the polymer particles from nonaqueous dispersion processes, based in particular on polyesters, as a powder coating is addressed in DE-C-21 52 515. Here, an existing polymer is brought into dispersion at a temperature <200° C. and, by addition pigments, in some cases at room temperature, a coloration is achieved. However, the resulting particles are described as substantially spherical “aggregates” of primary polymer particles and pigment particles. The isolation of material by spray drying leads to apparently to relatively large structures which it was necessary to convert back into a fine powder by mechanical means. Following the breaking up of the initially formed agglomerates, the stated particle size range is from about 2 to 50 μm, although there is no information whatsoever about the mean particle size or the particle size distribution.
The use, as described in DE-C-21 52 515, of a polymer which has already been condensed to high molecular weights as a starting product for dispersion preparation, moreover, has the following disadvantages: the already considerable viscosity of the polymers makes it difficult to achieve good division of the melt and to obtain a homogeneous particle size distribution.
U.S. Pat. No. 5,312,704 describes a toner composition comprised of pigment particles, and a resin comprised of a monomodal polymer resin or blends. This still suffers from issues described above in the extrusion blending followed by milling process, plus the dispersity of pigment particles as opposed to dyes. U.S. Pat. Nos. 5,660,963, and 5,556,732 all describe polyester resins blended with colorants in a melt extruder, followed by milling.
U.S. Pat. No. 5,346,798 describes a suspension polymerization method to make toner particles. This is .an aqueous dispersion method used to make addition polymers, and is not applicable to the non-aqueous dispersion method described here to make condensation polymer particles.
U.S. Pat. No. 5,621,055 describes a process for producing polymer particles with irregular shapes using a water soluble monomer in a system with a hydrophobic organic solvent, an aqueous solution of the water soluble monomer, and an anionic surfactant.
Accordingly, it is an object of this invention to provide for a manufacturing process to make spherical polyester particles of narrow particle size distribution in one step from either a mixture of monomers or a mixture of oligoesters. The process can be exactly adjusted to pick a mean particle size anywhere in the range of from 1 to 200 μm, and can produce particles of very narrow particle size distribution. Particles made by this process have utility in a variety of applications, including applications as powder coatings and as particles suitable for application for toners and use in high resolution electophotography.
Other objects and advantages of the present invention shall become apparent from the accompanying description and examples.
DESCRIPTION OF THE INVENTION
The present invention achieves this object and provides a process for the production of spherical, non-porous polyester particles which have a mean particle size of between 1 and 200 μm, and a particle size distribution (d 90 −d 10 /d 50 )<1.5, preferably<1.2 which can be used for a variety of applications such as powder coatings, binder systems, adhesives, toners and use in electophotography.
The novel, spherical polyester particles are prepared by:
A. Producing a melt of the starting monomers or oligoesters for the polyester.
B. Slowly adding the molten starting material for the polyester to a rapidly stirred, inert high-boiling heat transfer medium at a temperature which is at least as high as the softening temperature of the starting materials, in the presence of at least one organic dispersion stabilizer, and
C. then heating the reaction mixture to a temperature in the range from 120-280° C., with simultaneous removal of the condensation byproducts, until the polyester has the desired molecular weight, and
D. subsequently and optionally, at a temperature of from 25 to 220° C. addition of additives, if desired, such as charge control agents or flow control agents, end capping reagents and crosslinkers, and
E. thereafter cooling reaction mixture to within the range which is below the softening temperature of the polyester and separating off the polyester powder, and washing off the residual heat transfer medium with an inert, volatile solvent which may be easily removed?in a drying step and drying of the resulting powder.
The dispersion can be dosed in relatively amounts from 0% to 100% either in the molten starting material or in the preheated heat transfer material in order to optimize the particle forming process.
The particle size is controlled by the nature of the polyester employed, the rate of stirring, and most importantly, the amount of organic dispersion stabilizer used and the method of dosing. The particle size distribution is controlled uniquely by the slow addition of the oligoester or monomer melt potentially containing a certain amount of the organic dispersion stabilizer to the heated, stirred solution of heat transfer medium that contains the residual dispersion stabilizer. In contrast, when a mixture of oligoester (or monomers), heat transfer medium and dispersion medium is combined in the cold (room temperature) state and then heated together with stirring, the particle size average (d 50 ) can still be controlled via the above parameters, but the particle size distribution is much larger.
In general the particle size is reduced in raising the stirrer speed. In doing so the span is slightly broadened simultaneously. To circumvent this it is possible to raise the content of the dispersion stabilizer which results also in a smaller average particle size and has only a minor effect on the particle size distribution.
The starting materials employed are preferably oligoesters having viscosity of less than 1000 mPas (measured at 200° C.), in particular<500 mPas, which comprise units of the following formulae:
70 to 100 mol % of structural groups of formula —CO—A1—CO— (1)
0 to 30 mol % of structural groups of the formula —CO—A2—CO— (2)
0 to 50 mol % of structural groups of the formula —O—A3—CO— (3)
0.1 to 10 mol % of structural groups of the formula —CO—A4—CO— (4), preferably 1 to 5 mol %, more preferably 3 mol %.
and diol structural groups of the formula —O—D1—O— (5), O—D2—O— (6), and O—D3—O— (7) in which
A1 is 1,4-phenylene-, 2,6-naphthylene- or 4,4′-biphenylene radicals, which can be present individually or in any desired mixture,
A2 is aromatic radicals other than A1 or araliphatic radicals having 5 to 16, preferably 6 to 12, carbon atoms or cyclic or acyclic aliphatic radicals having 2 to 10 carbon atoms, preferably 4 to 8 carbon atoms.
A3 is aromatic radicals having 5 to 12, preferably 6 to 10, carbon atoms,
A4 is aromatic radicals having an anionic substituent, such as sulfonate, phosphonate, etc.
D1 is alkylene or polymethylene groups having 2 to 4 carbon atoms or cycloalkane or dimethylenecycioalkane groups having 6 to 10 carbon atoms and,
D2 is alkylene or polymethylene groups having 3 to 4 carbon atoms or cycloalkane or dimethylenecycloalkane groups having 6 to 10 carbon atoms other than D1, or bis-phenol A type moieties, or straight-chain or branched alkanediyl groups having 3 to 15, preferably 4 to 8, carbon atoms or radicals of the formula —(C2H4—O)m—C2H4—, in which m is an integer from 1 to 40, where m is preferably 1 or 2 for contents of up to 20 mol % and groups where m=10 to 40 are preferably present only in contents of less than 5 mol %.
D3 is alkylene or polymethylene groups having 2 to 4 carbon atoms or cycloalkane or dimethylenecycloalkane groups having 6 to 10 carbon atoms, or straight-chain or branched alkanediyl groups having 3 to 15, preferably 4 to 8, carbon atoms or radicals of the formula —(C2H4—O)m—C2H4—, in which m is an integer from 1 to 40, where m is preferably 1 or 2 for contents of up to 20 mol % and groups where m=10 to 40 are preferably present only in contents of less than 5 mol %. These groups have an anionic substituent, for example sulfonate, phosphonate.
The aromatic radicals A2 and A3 in their turn can also carry one or two substituents. Preferably, substituted radicals A2 and A3 carry only one substituent. Particularly suitable substituents are alkyi having 1 to 4 carbon atoms, alkoxy having 1 to 4 carbon atoms, and halide, such as chlorine.
Preferably, in accordance with the above statement, the dicarboxylic acid-diol precondensate employed as the starting material for the specific embodiment of the process according to the invention is a reaction product of one or more dicarboxylic acids of the formula HOOC—A1—COOH and one or more dicarboxylic acids of the formula HOOC—A4—COOH and, if appropriate, one or more dicarboxylic acids of the formula HOOC—A2—COOH or hydroxycarboxylic acids of the formula HO—A3—COOH. or functional derivatives of such di- or hydroxycarboxylic acids with one or more diols of the formula HO—D1—OH, and if appropriate one or more dials of the formula HO—D2—OH, in which, in addition to the esters formed from the starting materials, lower polycondensation products (oligomers) and as a rule small amounts of the starting materials are present.
Less preferably, in accordance with the above statement, the dicarboxylic acid-diol precondensate employed as the starting material for the specific embodiment of the process according to the invention is a reaction product of one or more dicarboxytic acids of the formula HOOC—A1—COOH and, if appropriate, one or more dicarboxylic acids of the formula HOOC—A2—COOH or hydroxycarboxylic acids of the formula HO—A3—COOH or functional derivatives of such di- or hydroxycarboxylic acids with one or more diols of the formula HO—D1—OH and HO—D3—OH, and if appropriate one or more diols of the formula HO—D2—OH, in which, in addition to the esters formed from the starting materials, lower polycondensation products (oligomers) and as a rule small amounts of the starting materials are present.
It is preferred first of all to prepare oligoesters of the above described composition in the melt by heating the carboxylic acid components, such as terephthalic, isophthalic, or 5-sulfonyl isophthalic acid, to name just a few, in the form of the free acid or as low molecular mass alkyl esters, together with the diol components, for example ethylene glycol, 1,2-propanediol, 2-methyl-1,3-propanediol, neopentylglycol or bis-hydroxvmethylcyclohexane, in the melt in the presence of a transesterification catalyst, such as compounds of manganese, zinc, tin, antimon or titanium, until the majority of the condensation products water or the lower alkanols, respectively, have been distilled off. In the course of this operation, however, no significant increase is observed in the viscosity of the melt. At 200° C., the viscosity is still <1000 mPas.
It is also possible to make the above oligoesters in the presence of additives such as charge control agents or flow control agents, which are admixed to the monomer mixture before the melt condensation.
An oligomer mixture of this kind can be converted, for example, into a novel dispersion directly at elevated temperature by combination with heat transfer oil and dispersant contained in the oil and/or in the oligomer mixture. This combination may be made preferably by addition of the molten precondensate to a mixture of preheated heat transfer oil and dispersant to give the narrowest particle size distribution. However, it is possible to cool the oligomer mixture for the purpose of storage, which would then be heated and melted before mixing with the heat transfer medium containing dispersant.
In addition, the oligomer mixture can be combined with heat transfer medium and/or dispersant in the cold state, then heated with stirring to conduct the dispersion polymerization reaction.
Less preferably, it is also possible to carry out the preparation of the oligomers in the actual dispersion, meaning the reaction can be conducted starting from monomers, without going through the initial melt-condensation to form the above oligoesters.
In a practical embodiment of the novel process the starting materials, preferably as an oligomer mixture, are added in step (a) in the molten state to a heated, stirred mixture of an inert, high boiling heat transfer medium and at least one organic dispersion stabilizer or dispersion stabilizer mixture. The mixture is heated to a temperature which must lie above the softening temperature of the starting materials, judiciously in the range of from 150 to 280° C.
Heat transfer media (dispersion media) which have proven particularly appropriate are aliphatic heat transfer oils having a boiling point in the range above 140 to 380° C. Such heat transfer oils are preferably, in the technical sense, free from aromatic structural groups: in other words, they contain not more than 2% by weight, more preferably not more than 1% by weight, of aromatic constituents.
Owing to the low polarity of these oils, which are marketed, for example, by Exxon Chemical under the trade names ®Isopar, ®Exxol, or ®Norpar, the polyesters are essentially not swollen. This is a problem which occurs in some cases for aromatic oils, which in principle are equally suitable for the dispersion process.
General rules for the design of appropriate polymeric dispersion stabilizers are given by Keith Barett in “Dispersion Polymerization in Organic Media”, John Wiley and Sons, London, 1975 on pages 45 to 110. Principal requirements are solubility of the polymeric dispersion stabilizer in the dispersion medium used, and polar or reactive groups which allow strong interaction with the particles that are to be dispersed.
For the novel process it is preferred to employ amphiphilic copolymers, preferably organic copolymers, or surface-modified inorganic compounds. Examples of the later are phyllosilicates surfaced-modified with trialkytammonium salts, especially bentonite surface-modified with tralkylammonium salts, or amphiphilic copolymers comprising a polar polymer unit for example poly-N-vinyl pyrrolidone, and an apolar polymer unit, for example long-chain α-olefins such as 1-eicosene.
Such amphiphilic copolymers are marketed by the company ISP Global under the tradename ®Antaron and have been found particularly appropriate. As described, for example, in EP-B-0 392 285. Antaron has already been employed successfully at relatively low temperatures for stabilizing polyurethane dispersions. It has been found that Antaron can be also employed with advantage, however, at temperatures up to 300° C. and results in excellent stability of the dispersions.
The content of the dispersion stabilizer is, in accordance with the invention, in the range from 0.1 to 6% by weight based on the polyester, preferably in the range of from 0.3 to 4% by weight and, in particular, in the range of from 0.5 to 3% by weight in order to obtain particles having the desired size.
In a subsequent step (b) the reaction mixture is heated further to a temperature in the range of from 120 to 280° C. in particular from 200 to 250° C., with the resulting condensation byproducts being removed in parallel. The temperature is maintained until the polyester has reached the desired molecular weight, which is usually in the range of Mn=1000 to 20,000, preferably in the range of 2000 to 10,000. Of decisive importance for the molecular weight is the duration of the reaction, which can be monitored by taking samples.
Following the conclusion of the condensation in step (b), it is also possible, in order to optimize the charge behavior of the toner particle or the coating properties of the polyester—as is desirable for optimum surface quality or transparency—to add additives such as charge control agents, flow assistants or devolatilization assistants, for example. This is done by cooling the mixture to 25 to 200° C. and adding the desired additives at the same time as stirring the reaction mixture. These additives can be added as described above without impacting negatively on the dispersion stability or particle formulation.
The temperature of the reaction mixture is reduced to a temperature which is below the softening temperature of the polyester, preferably <60° C. In this process the polyester is obtained in powder form. The resulting colorless, spherical polyester particles are separated off from the supernatant reaction solution, washed with a volatile, aliphatic hydrocarbon, such as hexane, isohexane, cyclohexane, pentane or butane, to remove excess heat transfer oil, then dried, preferably in a vacuum tumble dryer, at a temperature below the softening point of the polyester.
The polyester particles obtained in the process described are transparent and can be prepared with any desired molecular weight, for example in the range of from Mn=1000 to Mn=20,000, but/even as high as Mn=50,000. The yield is >95%, in general even greater than >98%, especially if the reaction is conducted on a relatively large scale. There are virtually no instances of adhesion in the reactor which could lead to a reduction in yield.
By means of the novel process it is possible to obtain spherical polyester particles having a mean particle size (d 50 ) of from 1 to 200 μm, and a particle size distribution (d 90 −d 10 )/d 50 of <1.5, in particular <1.2 and preferably ≦1.0.
Because of their tailorable size the polyester particles produced according to the instant process are particularly suited for the use in a number of applications. Particles with small sizes may be employed for instance for toners, use in electophotography, while particles with larger sizes, in the range of 20 to 50 μm are useful for the production of powder coatings.
EXAMPLES
Characterization
Inherent Viscosity:
Measured at 25° C. under 2.0% concentration (weight/volume) in N-methyl pyrrolidone containing 0.06% of lithium bromide.
Particle size:
Either dried powder or as-polymerized dispersion was well mixed with Heptane by ultrasonic then evaluated with laser light scattering method using a Malvern Mastersizer® at room temperature.
Glass transition temperature:
Evaluated on the second heating profile with a differential scanning calorimeter (DSC) using 10° C./min. heating rate.
Residual oil in dried powder:
Dried powder was dissolved into organic solvent, e.g. methylene chloride, then measured with gas chromatography. A peak caused by residual oil was calibrated with internal standard.
Residual washing solvent:
Evaluated by thermal gravity analysis (TGA) heating from 35° C. to 300° C. with 10° C./min. under nitrogen. Weight loss at 150° C. from 50° C. was calculated as an amount of residual solvent.
Example 1
NAD Polymerization from Precondensate with 50% Antaron in the Precondensate and 50% Antaron in the Heat Transfer Oil
Into an 250 liter stainless steel reactor equipped with an agitator and a packed column was added dimethyl terephthalate (161.9 Kg), dimethyl-5-sulfonyl isophthalate sodium salt (7.6 Kg), ethylene glycol (64.0 Kg), 2-methyl-1,3-propandiol (23.2 Kg), and dibuthyltinoxide (52.5 gram). The mixture was heated up to 150° C. and held for 30 minutes under nitrogen blanket then heated again to 200° C. in 270 minutes with removing methanol which was the byproduct from the ester inter-exchange reaction between dimethylester and diols. Kept at the temperature for 90 minutes to get 31.4 Kg of distillate. The mixture was cooled down to 150° C. and discharged from the reactor and cooled further. About 200 Kg of waxy white solid obtained (Precondensate A).
Into a 1.5 liter stainless steel main reactor equipped with a 6-blade-type agitator was added isoparaffinic oils, Isopar® P (150 gram) and Isopar® L (300 gram) provided by Exxon Chemical Europe Inc., and vinylpyrrolidone copolymer. Antaron® V220 (6.75 gram) provided by ISP. They were held at 190° C.
A 518.6 gram of solid Precondensate A was weighted in a upper 1.5 liter stainless steel reactor together with Antaron® (6.75 gram) and heated up to 190° C. It melted above 140° C. and became water-like thin liquid at 190° C.
The molted Antaron containing Precondensate A was slowly added into the 1.5 liter reactor containing oils and Antaron within 7 minutes under high-speed stirring (1000 rpm) through a preheated metal tube with a control valve. The molten precondensate reached directly to the oil-surface. The resulting dispersion was kept for another 10 minutes at 190° C.
Then the dispersion was heated up to 210° C. in 30 minutes under nitrogen flow of 25 liter per hour and the constant stirring. The isoparaffinic oil which was a dispersion medium in this stage began to boil at 194° C. The vapor was introduced into a phase-separator through a water-cooler where the distilled ethylene glycol was separated from the oil. The phase-separator held ca. 10 ml of the distilled oil and the rest returned to the dispersion from the top of the reactor through the glass tube where the running oil touched the vapor mixture. The dispersion was kept at 210° C. for 120 minutes removing ethylene glycol. A 57.3 gram of distillate was finally collected through the phase-separator. Then the dispersion was cooled down to ambient temperature and discharged.
The dispersion was filtered with polyester taffeta with pore size of about 40 micron. The filtered powder cake was washed three times with a 900 ml of iso-hexane then dried at 40° C. under vacuum overnight A 440 gram of fine white powder was obtained with a particle size (volume-average size), 11 micron, span 1.18 and I.V., 0.11 dl/g. The dried powder contained 1.6% of residual oil and 1.0% of isohexane.
Example 2
NAD Polymerization from Precondensate with 100% Antaron in the Precondensate
Into an 250 liter stainless steel reactor equipped with an agitator and a packed column was added dimethyl terephthalate (161.9 Kg), dimethyl-5-sulfonyl isophthalate sodium salt (7.6 Kg), ethylene glycol (64.0 Kg), 2-methyl-1,3-propandiol (23.2 Kg), and dibuthyltinoxide (52.5 gram). The mixture was heated up to 150° C. and held for 30 minutes under nitrogen blanket then heated again to 200° C. in 270 minutes with removing methanol which was the byproduct from the ester inter-exchange reaction between dimethylester and diols. Kept at the temperature for 90 minutes to get 31.4 Kg of distillate. The mixture was cooled down to 150° C. and discharged from the reactor and cooled further. About 200 Kg of waxy white solid obtained (Precondensate A).
Into a 1.5 liter stainless steel main reactor equipped with a 6-blade-type agitator was added isoparaffinic oils, Isopar® P (150 gram) and Isopar® L (300 gram) provided by Exxon Chemical Europe Inc. They were held at 190° C.
A 518.6 gram of solid Precondensate A was weighted in a upper 1.5 liter stainless steel reactor together with Antaron® (13.5 gram) and heated up to 190° C. It melted above 140° C. and became water-like thin liquid at 190° C.
The molted Precondensate A containing Antaron was slowly added into the 1.5 liter reactor within 7 minutes under high-speed stirring (1000 rpm) through a preheated metal tube with a control valve. The molten precondensate reached directly to the oil-surface. The resulting dispersion was kept for another 10 minutes at 190° C. Then the dispersion was heated up to 210° C. in 30 minutes under nitrogen flow of 25 liter per hour and the constant stirring. The isoparaffinic oil which was a dispersion medium in this stage began to boil at 194° C. The vapor was introduced into a phase-separator through a water-cooler where the distilled ethylene glycol was separated from the oil. The phase-separator held ca. 10 ml of the distilled oil and the rest returned to the dispersion from the top of the reactor through the glass tube where the running oil touched the vapor mixture. The dispersion was kept at 210° C. for 120 minutes removing ethylene glycol. A 48.2 gram of distillate was finally collected through the phase-separator. Then the dispersion was cooled down to ambient temperature and discharged.
The dispersion was filtered with polyester taffeta with pore size of about 40 micron. The filtered powder cake was washed three times with a 900 ml of iso-hexane then dried at 40° C. under vacuum overnight. A 459 gram of fine white powder was obtained with a particle size (volume-average size), 8 micron, span 1.42 and I.V., 0.08 dl/g. The dried powder contained 2.7% of residual oil and 1.6% of isohexane.
Example 3
NAD Polymerization from Precondensate with 100% Antaron in the Heat Transfer Oil
Into an 250 liter stainless steel reactor equipped with an agitator and a packed column was added dimethyl terephthalate (161.9 Kg), dimethyl-5-sulfonyl isophthalate sodium salt (7.6 Kg), ethylene glycol (64.0 Kg), 2-methyl-1,3-propandiol (23.2 Kg), and dibuthyltinoxide (52.5 gram). The mixture was heated up to 150° C. and held for 30 minutes under nitrogen blanket then heated again to 200° C. in 270 minutes with removing methanol which was the byproduct from the ester inter-exchange reaction between dimethylester and diols. Kept at the temperature for 90 minutes to get 31.4 Kg of distillate. The mixture was cooled down to 150° C. and discharged from the reactor and cooled further. About 200 Kg of waxy white solid obtained (Precondensate A).
Into a 1.5 liter stainless steel main reactor equipped with a 6-blade-type agitator was added isoparaffinic oils, Isopar® P (150 gram) and Isopar® L (300 gram) provided by Exxon Chemical Europe Inc. together with Antaron® (13.5 gram). They were held at 190° C.
A 518.6 gram of solid Precondensate A was weighted in a upper 1.5 liter stainless steel reactor and heated up to 190° C. It melted above 140° C. and became water-like thin liquid at 190° C.
The molted Precondensate A was slowly added into the 1.5 liter reactor within 7 minutes under high-speed stirring (1000 rpm) through a preheated metal tube with a control valve. The molten precondensate reached directly to the oil-surface. The resulting dispersion was kept for another 10 minutes at 190° C.
Then the dispersion was heated up to 210° C. in 30 minutes under nitrogen flow of 25 liter per hour and the constant stirring. The isoparaffinic oil which was a dispersion medium in this stage began to boil at 194° C. The vapor was introduced into a phase-separator through a water-cooler where the distilled ethylene glycol was separated from the oil. The phaseseparator held ca. 10 ml of the distilled oil and the rest returned to the dispersion from the top of the reactor through the glass tube where the running oil touched the vapor mixture. The dispersion was kept at 210 ° C. for 120 minutes removing ethylene glycol. A 48.2 gram of distillate was finally collected through the phase-separator. Then the dispersion was cooled down to ambient temperature and discharged.
The dispersion was filtered with polyester taffeta with pore size of about 40 micron. The filtered powder cake was washed three times with a 900 ml of iso-hexane then dried at 40° C. under vacuum overnight. A 390 gram of fine white powder was obtained with a particle size (volume-average-size), 6.8 micron, span 1.6 and I.V., 0.18 dl/g. The dried powder contained 3.6% of residual oil and 1.6% of isohexane.
Example 4
Up-scaled NAD Polymerization from Precondensate with 100% Antaron in the Heat Transfer Oil
Into an 250 liter stainless steel reactor equipped with an agitator and a packed column was added dimethyl terephthalate (161.9 Kg), dimethyl-5-sulfonyl isophthalate sodium salt (7.6 Kg), ethylene glycol (64.0 Kg), 2-methyl-1,3-propandiol (23.2 Kg), and dibuthyltinoxide (52.5 gram). The mixture was heated up to 150° C. and held for 30 minutes under nitrogen blanket then heated again to 200° C. in 270 minutes with removing methanol which was the byproduct from the ester inter-exchange reaction between dimethylester and diols. Kept at the temperature for 90 minutes to get 31.4 Kg of distillate. The mixture was cooled down to 150° C. and discharged from the reactor and cooled further. About 200 Kg of waxy white solid obtained (Precondensate A).
Into a 100 liter stainless steel main reactor equipped with a 4blade-type agitator was added isoparaffinic oils. Isopar® P (11 kg) and Isopar® L (22 kg) provided by Exxon Chemical Europe Inc. together with Antaron® (695 g). They were held at 190° C.
A 35 kg of solid Precondensate A was weighted in a upper 60 liter stainless steel reactor and heated up to 190° C. It melted above 140° C. and became water-like thin liquid at 190° C.
The molted Precondensate A was slowly added into the 100 liter reactor within 7 minutes under high-speed stirring (1000 rpm) through a preheated metal tube with a control valve. The molten precondensate reached directly to the oil-surface. The resulting dispersion was kept for another 10 minutes at 190° C.
Then the dispersion was heated up to 210° C. in 2.5 hours under nitrogen flow of 250 liter per hour and the constant stirring. The isoparaffinic oil which was a dispersion medium in this stage began to boil at 194° C. The vapor was introduced into a phase-separator through a water-cooler where the distilled ethylene glycol was separated from the oil. The phase-separator held ca. 1.5 l of the distilled oil and the rest returned to the dispersion from the top of the reactor through the glass tube where the running oil touched the vapor mixture. The dispersion was kept at 210° C. for 3 hours removing ethylene glycol. A 5 kg of distillate was finally collected through the phase-separator. Then the dispersion was cooled down to ambient temperature and discharged.
The dispersion was filtered with polyester taffeta with pore size of about 40 micron. The filtered powder cake was washed with iso-hexane then dried at 40° C. under vacuum. A 31 kg of fine white powder was obtained with a particle size (volume-average size), 4.9 micron, span 1.2 and I.V., 0.22 dl/g. The dried powder contained 3% of residual oil.
Example 5
NAD Polymerization from Monomers with 100% Antaron in the Heat Transfer Oil
Into an 1.5 liter stainless steel reactor equipped with an agitator and a packed column was added dimethyl terephthalate (208.8 g), dimethyl isophthalate (196.3 g), dimethyl-5-sulfonyl isophthalate sodium salt (19.1 g), 1,2-propanediol (245.5 g) and dibuthyltinoxide (0.270 g). The mixture was heated up to 150° C. and held for 30 minutes under nitrogen blanket then heated again to 220° C. in 5 hours with removing methanol which was the byproduct from the ester inter-exchange reaction between dimethylester and diols. Kept at the temperature for 90 minutes to get 128 g of distillate. The temperature is then reduced to 190° C. The mixture was then directly discharged into the NAD reactor.
Into a 1.5 liter stainless steel main reactor equipped with a 6-blade-type agitator was added isoparaffinic oils, Isopar® P (150 gram) and Isopar® L (300 gram) provided by Exxon Chemical Europe Inc. together with Antaron® (18 gram). They were held at 190° C.
The resulting portion of precondensate was slowly added as a waterlike thin liquid into the 1.5 liter reactor within 7 minutes under high-speed stirring (1000 rpm) through a preheated metal tube with a control valve. The molten precondensate reached directly to the oil-surface. The resulting dispersion was kept for another 10 minutes at 190° C.
Then the dispersion was heated up to 210° C. in 30 minutes under nitrogen flow of 25 liter per hour and the constant stirring. The isoparaffinic oil which was a dispersion medium in this stage began to boil at 194° C. The vapor was introduced into a phase-separator through a water-cooler where the distilled ethylene glycol was separated from the oil. The phase-separator held ca. 10 ml of the distilled oil and the rest returned to the dispersion from the top of the reactor through the glass tube where the running oil touched the vapor mixture. The dispersion was kept at 210° C. for 4.5 hours removing ethylene glycol. A 50 g of distillate was finally collected through the phaseseparator. Then the dispersion was cooled down to ambient temperature and discharged.
The dispersion was filtered with polyester taffeta with pore size of about 40 micron. The filtered powder cake was washed three times with a 900 ml of iso-hexane then dried at 40° C. under vacuum overnight. A 490 g of fine white powder was obtained with a particle size (volume-average size), 6.4 micron, span 0.8 and I.V., 0.20 l/g. The dried powder contained 3.5% of residual oil and 1% of isohexane.
Example 6
NAD Polymerization
250 g of molten precondensate (containing 8.5 mol % isopththalic acid, 37.5% terephthalic acid and 54 mol % neopentytgiycole) were added to a mixture of isoparaffinic oils (Isopar® L (125 gram) and Isopar® P (125 gram) provided by Exxon Chemical Europe Inc.) together with Antaron® (3.75 gram) in a 1.5 liter stainless steel main reactor equipped with a 6-blade-type agitator at 190° C. and stirred at 1800 rpm. Nitrogen flow was held at 25 l/h.
0.03 g of dibutyltinoxide were added and the mixture was heated to 217° C. within 20 minutes. Distillation of condensation products continued for 135 minutes. Then, the dispersion was cooled down to ambient temperature and discharged.
A sample of the powder dispersed in oil was used for determination of particle size distribution.
The dispersion was filtered with polyester taffeta with pore size of about 40 micron. After filtration, the powder was washed three times with 600 ml of isohexane and dried at 40° C. under vacuum of 200 mbar overnight.
250 g of fine white powder was obtained with a average diameter of 21 μm, a span of 1.0 and an inherent viscosity of 9.7 ml/g.
Examples 7 to 12
NAD Polymerisation
Procedure of NAD polymerisation according to Example 6.
TABLE 1
average particle size (diameter)
Ex.
Oil
[μm]
span
7
Isopar L, 125 g
29
1.0
Isopar P, 125 g
8
Norpar 15, 250 g (Exxon)
29
1.1
9
Risella G05, 250 g (Shell)
22
1.15
10
Isopar L, 125 g
19
0.7
Isopar P, 125 g
11
Norpar 12, 156 g
20
1.2
Norpar 15, 94 g
12
Norpar 12, 156 g
23
1.1
Norpar 15, 94 g
Comparative Example 1 NAD Polymerisation
250 g of precondensate (containing 8.5 mol % isopththalic acid, 37.5% terephthalic acid and 54 mol % neopentylglycole) were added to a mixture of isoparaffinic oils (Isopar® L (125 gram) and Isopar® P (125 gram) provided by Exxon Chemical Europe Inc.) together with Antaron® (3.75 gram) and 0.03 g of dibutyltinoxide in a 1.5 liter stainless steel main reactor equipped with a 6-blade-type agitator at ambient temperature. Nitrogen flow was held at 25 l/h. The mixture was heated up to 217° C. within 20 minutes and stirred at 1800 rpm.
Distillation of condensation products continued for 90 minutes. Then, the dispersion was cooled down to ambient temperature and discharged.
A sample of the powder dispersed in oil was used for determination of particle size distribution.
The dispersion was filtered with polyester taffeta with pore size of about 40 μm. After filtration, the powder was washed three times with 600 ml of isohexane and dried at 40° C. under vacuum of 200 mbar overnight.
250 g of fine white powder was obtained with a average diameter of 36 μm and a span of 1.55.
Comparative Example 2 NAD polymerisation
Procedure of NAD polymerisation according to Comparative Example 1.
250 g of fine white powder was obtained with a average diameter of 25 μm and a span of 1.6. | The invention relates to a process for the production of spherical, polyester particles, wherein the particle size can be exactly adjusted in the range of 1 to 200 μm and a particle size distribution with a span (=d90−d10/d50)≦1.5, as well as the use of the produced particles for toner compositions in electrophotographic and direct printing systems and powder coatings. | 8 |
FIELD OF THE INVENTION
[0001] This invention relates to a monitor and method for the monitoring of the concentration of oxygen in a fuel or in an ullage over a fuel. More particularly, although not exclusively, the monitor and method of the invention may find specific application in measuring the concentration of oxygen in or above aviation fuel, for example, in the fuel tank of an aircraft or in a fuel supply tanker.
BACKGROUND ART
[0002] Aircraft fuel naturally contains some dissolved gas, typically air, and therefore typically contains some dissolved oxygen. The amount of oxygen in fuel decreases with pressure. Therefore, at cruising altitude (i.e., at low ambient pressure), oxygen is degassed from the fuel. From a safety standpoint, it is desirable to have fuel or fuel-rich environments contained in an inert atmosphere. Thus, the release of oxygen from fuel in such an environment is highly undesirable.
[0003] Also, evolved gas from the fuel may increase the risk of air pockets forming in the fuel system of the aircraft. Some aircraft fuel tank arrangements use gravity feed systems including siphons to transfer fuel within the fuel system. Air pockets present in the fuel tank system may act to disrupt the siphon effect in gravity feed systems, the pressure head possibly being insufficient to push the air down the pipes.
[0004] One known technology for estimating oxygen concentration uses electrochemical detection. However, most commonly used electrolytes are not suitable for extreme operating temperatures. In particular, they are not suitable for the low temperatures encountered in aviation applications.
[0005] More recently, oxygen monitors for aircraft fuel tanks have been developed in which the oxygen concentration is monitored by means of a probe containing a luminescent substance. Oxygen acts to quench the luminescence of the luminescent substance and therefore the concentration of oxygen can been derived from measurements of the light emitted from the luminescent substance.
[0006] WO 03/046422 describes one such system in which the oxygen concentration in an aircraft fuel tank is monitored by means of a monitor containing a fluorescent ruthenium complex.
[0007] US 2006/0171845A1 discloses the use of platinum (II) tetrakis(pentafluorophenyl)porphyrin as a fluorescent compound held within an amorphous fluorinated polymer matrix for the detection of oxygen in an aircraft fuel tank.
[0008] In order to be suitable for use in an aircraft fuel tank a monitor must be capable of withstanding the low temperatures, for example, −20° C. to which the fuel tanks are exposed when the aircraft is in flight. Furthermore, for obvious reasons it is desirable that the monitor be reliable and have a lifetime which is numbered in years rather than months. Furthermore, the materials used in the monitor must be compatible with aviation fuel.
[0009] The present inventors have found that the luminescence of some substances is effectively switched off by contact with the aviation fuel and therefore the sensing mechanism becomes inoperative. The reason for that is not known but it is possible that aviation fuel contains certain additives which act to prevent the luminescence. Furthermore, luminescent materials held in a polymer matrix can over time leach out from the polymer into the aviation fuel, thereby reducing the effectiveness of the monitor.
DISCLOSURE OF THE INVENTION
[0010] In order to mitigate at least some of the above mentioned problems the present invention provides a monitor for monitoring the concentration of oxygen in a fuel or in an ullage over a fuel comprising:
[0011] a sensing element comprising a luminescent substance comprising a luminophore and a support in which the luminophore is covalently bound to the support;
[0012] a light source arranged to irradiate the sensing element with light; and
[0013] a photosensor arranged to detect light emitted from the luminescent substance.
[0014] The present inventors have found that covalently bonding the luminophore to a support effectively anchors the luminophore to the support and therefore inhibits leaching of the luminophore away from the sensing element and into the fuel. Surprisingly, the inventors have also found that covalently binding a luminophore to a support can counteract the inactivation of the luminophore by jet fuel, thereby allowing it to retain luminescent activity when used in contact with fuel.
[0015] In a particularly desirable embodiment, the monitor is suitable for use in an aircraft fuel tank. In a further embodiment the monitor is suitable for use in a ground based aviation fuel supply vehicle such as a fuel tanker or in an aviation fuel storage facility.
[0016] In a second aspect the invention provides an aircraft including a fuel tank provided with a monitor according to a first aspect of the invention.
[0017] In a third aspect of the invention, the invention provides a method of detecting oxygen in a fuel or in ullage space above a fuel comprising the steps of:
[0018] irradiating with light a sensing element comprising a luminescent substance comprising a luminophore covalently bound to a support, thereby exciting luminescence in the luminescent substance; and
[0019] detecting light emitted from the luminescent substance.
[0020] Embodiments of the invention can advantageously be used in fuel-flow control applications in aviation to provide a fast and accurate means of monitoring the dissolved oxygen concentration in fuel. With knowledge of dissolved oxygen concentration in fuel, the risk of air pockets in pipes under gravity feed conditions may be gauged and appropriate action taken.
[0021] The term ‘luminescent substance’ as used herein is to be understood as referring to a substance which is useful in the detection of oxygen in accordance with the invention by means of luminescence and luminescence quenching. Luminescence can be considered to be an emission of light which does not result from the temperature of the luminescent substance but rather from the excitation of the luminescent substance, for example, by incident light. Luminescent quenching is the reduction of luminescence which results from the presence of a particular substance such as oxygen. Contact with a quenching substance allows the excited luminescent substance to move from an excited state to a ground state without emitting light, resulting in a reduction in the intensity of the luminescence.
[0022] Light emitted by the luminescent substance must be distinguished from light which is reflected or scattered from the indicated substance.
[0023] The term ‘light’ as used herein includes visible, infrared and ultraviolet light.
[0024] Luminescence is generally sub-divided into two forms known as fluorescence and phosphorescence which are well understood by the skilled person. Most substances which are luminescent are either fluorescent or phosphorescent, but in some cases it is possible that luminescence occurs by a combination of the two mechanisms.
[0025] The term ‘luminophore’ refers to an atom or group of atoms within the luminescent substance which is responsible for the luminescent properties of the luminescent substance. The luminescent substance of the invention comprises a luminophore covalently bound to a support. The luminophore may be directly bonded by a single covalent bound to the support but preferably will be bound to the support via a bridging group as described in more detail below.
[0026] The term ‘support’ should be taken to refer to any solid or semi-solid material to which the luminophore can be covalently bonded and which is suitable for use in the monitor of the present invention.
[0027] Advantageously, the support is a high surface area material, for example, having a surface area of at least 50 m 2 /g, preferably at least 100 m 2 /g and especially preferably at least 150 m 2 /g. The support material may be a finely divided solid such as a powder. Optionally the support is selected from the group consisting of silica, alumina and clay. Silica is an especially preferred support material. In an alternative embodiment, the support may be a polymeric material. Optionally the polymeric material is cross-linked. The support may be, for example, polystyrene optionally cross-linked, for example, with divinylbenzyene. Poly(styrene-co-divinylbenzene) is commercially available in a number of different grades in the form of beads. Furthermore, a number of modified poly(styrene-co-divinylbenzenes) are available having amine substituents which may be conveniently used to form bridging groups with luminophore compounds. Modified silicas having amine groups attached to their surfaces are also commercially available.
[0028] The luminescent substance will typically be prepared by reacting a luminescent compound with a support material to arrive at a product in which a luminophore derived from the luminescent compound is covalently bonded to the support. The skilled person will be aware of a number of suitable luminophores and luminescent compounds for use in the invention. The luminophore may for example comprise a metal complexed with a macrocycle. In a preferred embodiment the luminophore is a metal porphyrin complex, for example a platinum porphyrin or a ruthenium porphyrin. Preferably, the luminophore is a platinum porphyrin complex and more preferably the luminophore is a fluorinated platinum porphyrin complex. An especially preferred luminophore is derived from the reaction of platinum (II) tetrakis(pentafluorophenyl)porphyrin with a support.
[0029] The luminophore desirably has a high quantum yield, that is, it efficiently converts incident radiation into emitted radiation of a different wavelength.
[0030] Preferably, the luminescent substance is a phosphorescent substance and the emitted radiation is phosphorescent radiation.
[0031] The luminophore is covalently bound to the support either by a direct covalent bond or by a bridging group containing a chain of covalent bonds between the support and the luminophore.
[0032] The bridging group may be any group which is suitable for covalently linking the support to the luminophore. Optionally the luminophore is covalently bound to the support via a bridging group comprising an amine, ether or thioether functional group. For example, the bridging group could be an alkyl amine, alkylether or an alkylthioether bridging group.
[0033] In one embodiment, the luminescent substance may be represented by the structural Formula (I);
[0000] Support-R-luminophore (I)
[0034] In which R is either a direct covalent bond or a bridging group.
[0035] Bridging group R in Formula (I) above is in one embodiment represented by the formula -A-N(A 1 )-, -A-O—, -A- or -A-S— where each A is a hydrocarbyl group including from 1 to 50 carbon atoms where hydrocarbyl is defined as an aliphatic or aromatic group optionally comprising one or more heteroatoms, and A 1 is a hydrocarbyl group comprising from 1 to 20 carbon atoms.
[0036] Optionally, the bridging group comprises one or more amine groups.
[0037] The luminescent substance is in one embodiment prepared by reacting a luminescent compound (which is a precursor to the luminophore group) with a support material. For example, the luminescent substance may be prepared by reacting a luminescent compound with a silica modified to carry on its surface amine-containing groups. As a particular example, the present inventors have prepared luminescent substances by reacting platinum (II) tetrakis(pentafluorophenyl)porphyrin with silicas carrying alkylamino groups on their surfaces.
[0038] The term ‘sensing element’ as used herein relates to any element arranged to detect the presence of oxygen in accordance with the present invention. For example, the sensing element may be a window of transparent polymeric material in which the luminescent substance is embedded.
[0039] The sensing element should be able to withstand the conditions experienced in use of the monitor, for example, where the monitor is a monitor in aircraft fuel tank the luminophore should be capable of withstanding repeated low temperatures and contact with aviation fuel over a working life of at least one month and preferably at least one year.
[0040] The sensing element of the invention comprises the luminescent substance. In some cases the luminescent substance may be used alone in its unmodified form as the sensing element, for example, where the luminescent substance is such that it can be attached directly to the tip of an optical fibre and is suitable for direct contact with the fuel to be monitored. However, it will often be preferred to combine the luminescent substance with one or more other materials to form the sensing element. For example, the luminescent substance may be dispersed in one or more polymeric matrix materials. Such polymeric materials may improve the mouldability of the mixture allowing the sensing element to be manufactured in a particular desired form. The matrix material will be desirably be chemically unreactive towards the luminescent substance, be stable in the presence of a fuel, be sufficiently transparent to the light irradiated onto the luminescent substance from the light source and to the light emitted from the luminescent substance, and also be sufficiently permeable to oxygen to allow oxygen from the fuel to travel through the matrix material to the luminescent substance in a reasonable timescale.
[0041] Polysiloxanes are known to have good oxygen permeability and in one embodiment the matrix material comprises a polysiloxane. For example, the matrix material may be a mixture of polystyrene and polysiloxane. Preferably, the matrix material comprises at least 1%, more preferably at least 3% by weight of polysiloxane. A preferred matrix material is a mixture of polystyrene and polysiloxane in which the polysiloxane is present in the range of from 1 to 20%, preferably 1 to 10% by weight.
[0042] Optionally, the polymeric matrix material is a film forming material and the sensing element is in the form a film or coating. The film may be prepared by known techniques, for example, either from a melt of the polymer matrix material and the luminescent substance or a liquid dispersion comprising the matrix material and the luminescent substance which dries to form a film. Advantageously, the sensing element is a film comprising a polymeric matrix material and the luminescent substance dispersed in the polymeric matrix material, the film being associated with, for example, in contact with one or more optical elements such as an optical fibre through which the incident and emitted light right radiation can be carried.
[0043] In addition to the light source, the sensing element and the photosensor, the monitor of the invention optionally comprises one or more additional optical elements such as filters, reflectors and optical fibres for conveying light to and from the sensing element. Preferably, the monitor comprises an optical fibre carrying light from the light source to the sensing element and an optical fibre for carrying light from the sensing element to the photosensor. The optical fibre carrying light from the light source to the sensing element is optionally the same optical fibre which is used to carry from the sensing element to the photosensor, that is, a single optical fibre is used for both tasks. Preferably, the or each optical fibre is in direct contact with the sensing element.
[0044] Preferably, the sensing element is mounted in a vessel for storing the fuel, for example, a fuel tank and the light source and photosensor are located outside the vessel and communicate with the sensing element via optical elements such as optical fibres. That arrangement has the advantages that the monitor occupies a minimum of space inside the fuel tank and the electrical components of the light source and photosensor are safely located remote from the fuel tank.
[0045] The light source may be a light-emitting diode (LED). The light source may comprise one or more LEDs. The or each LED may be low-power LEDs. For example, the LEDs may be configured to be operated by means of electrical power of less than 500 mW and preferably less than 100 mW. The or each LED may for example be arranged to emit light having a maximum radiant intensity of less than 10 mW/Sr (Watts per Steradian) and possibly less than 1 W/Sr. The or each LED may be arranged to emit light having a maximum power density of less than 1 kilowatt per cm 2 and possibly less than 10 watts per cm 2 . The light source when provided in the form of one or more LEDs may have the advantage of having a relatively long life span. For example, the estimated time to failure for the or each LED may exceed 10,000 hours of use. The average life time of the or each LED may therefore exceed several years, thereby requiring little or no maintenance. The light source may be a laser. The light emitted by the light source to excite the luminescent substance is optionally ultraviolet (UV) light. In an alternative embodiment, the exciting radiation is visible light.
[0046] The light source may comprise a filament light bulb. The light source may comprise a fluorescent tube. The light source may comprise one or more filters. The light source may be pulsed during operation of the monitor, such that the light source irradiates the substance with pulsed light. Alternatively, the light source is arranged to irradiate the substance with light of a substantially constant intensity during operation of the monitor.
[0047] The photomonitor may comprise a photodiode. The photomonitor may detect light in the visible spectrum. The monitor may comprise a filter arranged between the photomonitor and the sensing element. The filter may absorb substantially all light from the light source that is incident upon the filter. The filter may transmit light from the luminescent substance.
[0048] The monitor may be arranged to output a signal dependent on the intensity of light detected by the photomonitor. The monitor may be arranged to output a signal, which varies in inverse proportionality to changes in the electrical signal outputted directly by the photomonitor. The monitor may be arranged to output a signal, which is dependent on, for example proportional to, the concentration of oxygen in the fuel or ullage space as measured by the monitor. The output of the monitor may be derived from a measurement of the intensity of light as detected by the photomonitor at a time when the luminescent substance is being irradiated by the light source. Alternatively, or additionally, the output of the monitor may be derived, at least in part, from a measurement of the intensity of light as detected by the photomonitor at a time when the luminescent substance is not being irradiated by the light source.
[0049] Advantageously, the monitor is arranged to monitor the decay in intensity of light emitted from the luminescent substance following a pulse of incident radiation from a light source. By monitoring the rate of decay of emitted radiation rather than simply monitoring the intensity of emitted radiation at a given level of incident radiation the monitoring may be less subject to variations caused by aging of the sensing element.
[0050] The monitor of the invention may be used to give a single measurement of oxygen concentration. Alternatively, the monitor may be used to monitor the concentration of oxygen over a period of time or continuously.
[0051] The monitor of the invention may be used to monitor the concentration of oxygen in or above any fuel. Preferably, the fuel is a hydrocarbon-based fuel. The fuel may be a fuel derived from petroleum. In a preferred embodiment the fuel is a jet fuel. The fuel may comprise kerosene. The fuel may comprise a naphtha-kerosene. The fuel may, for example, be jet A, jet A-1, jet B, or TS-1 fuel. In a preferred embodiment the fuel is jet A fuel.
[0052] The fuel may be contained in any vessel such as a fuel tank or conduit such as fuel supply line. In a preferred embodiment, the monitor is located in a fuel tank and is in direct contact with the fuel in the fuel tank. In another preferred embodiment, the monitor is located in a fuel tank and is arranged to monitor the concentration of oxygen in an ullage space above the fuel.
[0053] In a further aspect the invention provides an aircraft including a fuel tank which is provided with a monitor according to the invention.
[0054] In a further aspect the invention provides a fuel handling apparatus which is provided with a monitor according to the invention. The fuel handling facility may be, for example, a fuel storage depot or a fuel tanker vehicle.
[0055] In a further aspect of the invention the invention provides a method of controlling the oxygen concentration in a fuel comprising the steps of:
[0056] providing a sensing element comprising a luminescent substance comprising a luminophore covalently bound to a support in contact with the fuel or in an ullage space above the fuel;
[0057] irradiating with light the sensing element thereby exciting luminescence is a luminescent substance;
[0058] detecting light emitted from the luminescent substance;
[0059] estimating the oxygen concentration in the fuel or the ullage space based on the detected light; and
[0060] treating the fuel with a diluent gas in dependence upon the estimated level of oxygen concentration.
[0061] The diluent gas may be nitrogen enriched air.
DETAILED DESCRIPTION
[0062] Certain illustrative embodiments of the invention will now be described in detail by way of example only.
Example 1
[0063] Photoluminescent Compounds Prepared from Silica as Support and Platinum (II) Tetrakis(Pentaflurophenyl)Porphyrin as Luminophore Precursor.
[0064] Four different functionalized silicas were used:
[0065] Aminopropyl functionalized silica;
2-(4-ethylenediaminobenzyl)ethyl functionalized silica; 3-(diethylenetriamino)propyl functionalized silica; and 3-propylethylenediamine functionalized silica.
[0069] The functionalised silicas were obtained from Fisher-Acros and typically 9% of the silanol (SiOH) groups were functionalised.
[0070] The structure of the functionalized silicas used can be regarded as, (idealized):
[0000]
[0000] where R═
—CH 2 —CH 2 —CH 2 —NH 2 (aminopropyl, AP) —CH 2 —CH 2 —CH 2 —NH—CH 2 —CH 2 —NH 2 (3-(ethylenediamino)propyl, PED) —CH 2 —CH 2 —CH 2 —NH—CH 2 —CH 2 —NH—CH 2 —CH 2 —NH 2 (3-(diethylenetriamino)propyl, DETAP) —CH 2 —CH 2 —C 6 H 4 —NH—CH 2 —CH 2 —NH 2 (2-(4-ethylenediaminobenzyl)ethyl, EDABE)
[0075] Platinum (II) tetrakis(pentaflurophenyl)porphrin has the structure:
[0000]
[0076] Without wishing to be bound by theory, the porphyrin is believed to undergo substitution of the para fluorine on one of the pentafluorophenyl groups, reacting with an NH 2 or NH group on the functionalised silica. (In the case of the silicas with more than one amino group, it has not yet been established which amino group has reacted). A molecule of HF is eliminated and the overall structure of the silica/porphyrin adduct, for example, the aminopropyl adduct, might thus be represented as:
Bulk silica-Si—O—CH 2 —CH 2 —CH 2 —NH-porphyrin
with the porphyrin being covalently bound to the silica through the aminopropyl bridging group.
[0078] And so in general, one possible structure for the luminescent compound is:
Silica-R-porphyrin, where R is a bridging group comprising an amino group.
[0080] Platinum (II) tetrakis(pentafluorophenyl)porphyrin (20 mg) and functionalized silica (500 mg), were stirred in diglyme (15 ml) at 140° C. for 6 hours, in anhydrous conditions. The solid product was obtained by filtration under reduced pressure, washed with toluene (4×5 ml) and dried at 50° C. for 12 hours.
[0081] Similar preparations were carried out at the increased temperature of 160° C., and it was found that the gains in terms of reaction rate were not significant. However, by increasing the initial mass of dye to 100 mg (instead of 20 mg), the yields were significantly increased.
Example 2
[0082] Luminescent Substances Prepared from Aminofunctionalised Polystyrene as Support and Platinum (II) Tetrakis(Pentafluorophenyl)Porphyrin as Luminophore Precursor.
[0083] Platinum (II) tetrakis(pentafluorophenyl)porphyrin (20 mg) and amino functionalized poly(styrene-co-divinylbenzene) (100 mg), were stirred in diglyme (15 ml) at 140° C. for 6 hours, in anhydrous conditions. The solid product was obtained by filtration under reduced pressure, washed with toluene (4×5 ml) and dried at 50° C. for 12 hours.
Example 3
Polymer Films Comprising Porphyrin/Silica Adducts.
[0084] The porphyrin/silica adducts prepared in Example 1 were incorporated into polymer films, according to the following method. The polystyrene used was ex. BDH, and had a molecular weight of approximately 100,000. The polysiloxane was in the form of a conformal coating from Dow Corning comprising 64% octamethyltrisiloxane, 30% mixture of dimethylsiloxane, methylmethoxysilane, phenylmethoxysilane, methyl silsesqioxane and phenyl silsesquioxane, 3% toluene and 1.7% trimethoxy(methyl)silane.
[0085] Toluene (5 g) was stirred with polystyrene (500 mg) and conformal coating (20 mg) until the polystyrene had dissolved. The porphyrin/silica adduct (20 mg) was added and dispersed by stirring. Films were cast on glass sides, allowing the toluene to evaporate on standing. A range of samples was prepared which contained various proportions of conformal coating and polystyrene. The polysiloxane content was kept greater than 3% by weight in order to retain air permeability.
Monitor Measurements
[0086] The porphyrin/silica adducts prepared in Example 1 were tested in both air and jet fuel A for oxygen sensing ability. The oxygen concentration was varied either by the use of vacuum or by flooding with nitrogen. In the latter case nitrogen was blown over the adduct dry or bubbled through jet fuel containing the adduct. The adducts were irradiated, at 400 nm, by either uv LEDs or a uv lamp. Changes in phosphorescence were noted (by visual inspection) for all of the samples. Photodiodes were used to measure emitted light.
[0087] All of the porphyrin/silica adducts displayed a rapid response to the presence of oxygen, which quenched the phosphorescence. Similar results were obtained with the samples in which the porphyrin/silica adduct was dispersed in a polystyrene/polysiloxane matrix.
Ageing Studies
[0088] The porphyrin/silica adducts were heated according to the following method in a range organic solvents, including jet fuel, to simulate ageing over a long period of time.
[0089] The porphyrin/silica adduct (120 mg) was stirred in toluene (10 ml) at 45° C. for 1 hour, to remove any traces of unbonded porphyrin. UV spectroscopy of a sample of the solvent then revealed no trace of dye. After filtering this was repeated using fresh solvent, heating and stirring for another 3 hours. Further UV measurements revealed no trace of porphyrin in the solvent. After stirring for 4 days at room temperature, more UV readings were taken, with no evidence of porphyrin dissolved in the dye.
[0090] This procedure was repeated with jet fuel, with the same results as for toluene. Filtered samples of the adducts revealed that they still functioned as oxygen sensors after these treatments. XPS studies have confirmed that the porphyrin is bonded to the silica.
[0091] The results show that the porphyrin remained bonded to the silica, and oxygen sensing ability was preserved. | A monitor for monitoring the concentration of oxygen in a fuel or in an ullage over a fuel comprises (i) a sensing element comprising a luminescent substance comprising a luminophore and a support in which the luminophore is covalently bound to the support, (ii) a light source arranged to irradiate the sensing element with light, and (iii) a photosensor arranged to detect light emitted from the luminescent substance. The luminescent substance may be, for example, a platinum porphyrin covalently bound to silica. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to semiconductor integrated circuits and particularly to silicon semiconductor integrated circuits having a radio frequency (RF) circuit processing an RF signal.
[0003] 2. Description of the Background Art
[0004] In recent years, as mobile phones have widely been used and wireless LANs have practically been used, semiconductor integrated circuits that are used in such electronics have been noted and RF semiconductor devices have been noted in particular. To provide electronics with high performance and miniaturize and produce it inexpensively, it is essential that an RF semiconductor device serving as a main component thereof provide high performance have a small size and be produced inexpensively.
[0005] Conventionally, group III-V compound semiconductor having high electron mobility such as GaAs has been a main stream of material for a substrate that is used in an RF semiconductor device. Group III-V compound semiconductor, however, is much more expensive than silicon semiconductor typically used as a material for substrates of semiconductor devices and has been an obstacle to inexpensively producing RF semiconductor devices.
[0006] The recent rapid advance in silicon MOS transistor microfabrication technology has now allowed silicon MOS transistors to have a small gate length less than 0.2 μm. Such silicon MOS transistors allow significantly improved transconductance Gm and have now achieved characteristics applicable as gigahertz RF semiconductor devices.
[0007] If a silicon MOS transistor can be used to fabricate an RF semiconductor device, a significant cost reduction can be achieved and it can also be expected that a baseband portion or any other similar logic circuit portion conventionally fabricated using silicon MOS process techniques is provided in the form of a single chip, and by System On Chip (SOP) a reduction in cost and that in area for mounting can also be achieved. Thus there is a demand for rapidly developing an RF semiconductor device using a silicon substrate and having more satisfactory characteristics.
[0008] As has been described above, a silicon RF semiconductor device has RF characteristics having attained a level sufficiently applicable as an RF semiconductor device. However, it has several disadvantages in SOPing with an RF switch circuit switching on/off an input and output of an RF signal (hereinafter an RF signal processing circuit other than the RF switch circuit will be referred to as a “specific RF circuit”). In particular, if it is used in a radio frequency range of no less than the 5 GHz band, the RF switch circuit's insertion loss is disadvantageously increased and SOPing can hardly be implemented.
[0009] In RF semiconductor devices that are used in mobile phones, wireless LANs and the like, as aforementioned, an RF switch circuit is a significantly important circuit. As shown in FIG. 18, typically a switch circuit 140 is configured by a transmission and reception switch circuit using a single pole double throw (SPDT) switch 140 ′. In reception, the switch receives an RF signal from an antenna 141 and transfers the signal to a reception portion's low noise amplifier (an RF low noise amplification circuit) 150 . In transmission, the switch receives an RF signal from a power amplifier 150 ′ and transmits the signal to antenna 141 .
[0010] Fabricating SPDT switch 140 ′ using an MOS transistor 130 allows SOPing with another, specific RF circuit. A possible, simplest configuration of the SPDT switch is shown in FIG. 19 by way of example. Furthermore, FIG. 20 is an equivalent circuit diagram of the FIG. 19 SPDT switch with a transmission side ON and a reception side OFF. In this SPDT switch an insertion loss increases for the following reason:
[0011] In FIG. 20, C d represents an MOS transistor's source/drain junction capacitance. Through source/drain junction capacitance C d a substrate resistance R si is connected to a circuit. Improving the MOS transistor's ON characteristics entails reducing an ON resistance R ON and a relatively large gate width of approximately 100 μm to 400 μm is accordingly used. As such, source/drain junction capacitance C d would assume a relatively large value. Furthermore, the source/drain junction capacitance C d impedance |z| is represented by 1/(2π×f×C d ) and it decreases for a gigahertz RF frequency range, since frequency f assumes a large value. Consequently, an RF signal flows to substrate resistance R si and an RF signal to be transmitted by a switch would have a loss in transmission, i.e., an insertion loss is introduced. As such, for an RF range (of no less than the 5 GHz band in particular) an insertion loss is significantly increased and a satisfactory switch circuit can hardly be fabricated.
[0012] An SOPed RF silicon semiconductor device needs to employ a substrate formed of silicon providing a small resistance (of approximately 10 mΩ to 10 Ω) to prevent latch-up. As such, in an RF switch circuit, with a large source/drain junction capacitance C d , as described above, the silicon substrate's resistance R si contributes to a significant loss. As such, SOPing with another specific RF circuit has significantly been difficult.
SUMMARY OF THE INVENTION
[0013] The present invention contemplates a semiconductor integrated circuit that can also provide high performance and high reliability when SOPing is employed to provide an RF switch circuit on a silicon substrate to switch on/off an input and output of an RF signal.
[0014] In accordance with the present invention a semiconductor integrated circuit includes a silicon substrate and first and second MOS transistors formed on the silicon substrate. The silicon substrate has a first region and a second region identical in conductivity to the first region and having a lower dopant concentration than the first region. The second MOS transistor is formed on a main surface of the second region and configures an RF switch circuit switching on/off an input and output of an RF signal. The first MOS transistor is formed on a main surface of the first region and configures a specific RF circuit other than the RF switch circuit.
[0015] Thus the first MOS transistor that is biased can provide a depletion layer larger in width, as seen in the direction of the thickness of the silicon substrate, than the second MOS transistor that is biased can. As such, the second MOS transistor can significantly be smaller in source/drain junction capacitance than the first MOS transistor. As a result, the first MOS transistor can be used to configure the specific RF circuit, which requires small-current-leakage characteristics, and the second MOS transistor can be used to configure the RF switch circuit, which essentially requires reduced source/drain junction capacitance, to provide a semiconductor integrated circuit with the specific RF circuit and the RF switch circuit arranged together on a single silicon substrate and having satisfactory characteristics. Note that they can discretely be fabricated in a conventional MOS process fabrication process simply by using an additional photomask.
[0016] The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In the drawings:
[0018] [0018]FIG. 1 is a cross section of a silicon semiconductor integrated circuit of a first embodiment of the present invention including an RF switch circuit and another specific RF circuit;
[0019] [0019]FIG. 2 represents a lateral, one-dimensional dopant concentration profile traversing source and drain diffusion layers of an n type MOS transistor of the RF switch circuit of the silicon semiconductor integrated circuit of the first embodiment;
[0020] FIGS. 3 - 8 show a process for fabricating the silicon semiconductor integrated circuit of the first embodiment;
[0021] [0021]FIG. 9 represents a result of a simulation of a longitudinal, one-dimensional dopant concentration profile traversing the source or drain diffusion layer of the n type MOS transistor of the RF switch circuit or that of an n type MOS transistor of the specific RF circuit in the silicon semiconductor integrated circuit of the first embodiment;
[0022] [0022]FIG. 10 represents a result of a simulation of a profile of an electric field in a silicon substrate of the silicon semiconductor integrated circuit of the first embodiment that is obtained when the RF switch circuit and the specific RF circuit have their n type MOS transistors biased;
[0023] [0023]FIG. 11 represents a result of an estimation of discrete source/drain passage characteristics of an MOS transistor of the RF switch circuit in the silicon semiconductor integrated circuit of the first embodiment by S parameter RF characteristics estimation;
[0024] [0024]FIG. 12 is a Smith chart of S parameter characteristics S 11 of the MOS transistor of the RF switch circuit in the silicon semiconductor integrated circuit of the first embodiment;
[0025] [0025]FIG. 13 represents a result of a measurement of a breakdown voltage between source and drain diffusion layers of the MOS transistor of the RF switch circuit in the silicon semiconductor integrated circuit of the first embodiment;
[0026] [0026]FIG. 14 is a cross section of an RF switch circuit of a silicon semiconductor integrated circuit of a second embodiment of the present invention;
[0027] [0027]FIG. 15 is a cross section of an RF switch circuit of a silicon semiconductor integrated circuit of a third embodiment of the present invention;
[0028] [0028]FIG. 16 is a circuit diagram showing one example of a configuration of an RF switch circuit in an exemplary application of the present invention;
[0029] [0029]FIG. 17 shows another example of the configuration of the RF switch circuit in the exemplary application of the present invention;
[0030] [0030]FIG. 18 shows a circuit configuration of an SPDT switch;
[0031] [0031]FIG. 19 is a circuit diagram of an SPDT switch using an MOS transistor to configure its circuit; and
[0032] [0032]FIG. 20 is an equivalent circuit diagram of the SPDT switch shown in FIG. 19.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] Hereinafter the present invention in embodiments will be described with reference to the drawings.
[0034] First Embodiment
[0035] The present invention in a first embodiment provides a silicon semiconductor integrated circuit with an RF switch circuit and another, specific RF circuit processing an RF signal that are SOPed on a single silicon substrate. Furthermore as the specific RF circuit a logic circuit such as a baseband portion may be included.
[0036] Configuration
[0037] Reference will initially be made to FIG. 1 to describe a configuration of the silicon semiconductor integrated circuit of the present embodiment. The silicon semiconductor integrated circuit in the present embodiment employs an MOS transistor as a semiconductor device used in the specific RF circuit and it also employs an MOS transistor in the RF switch circuit.
[0038] Of the above MOS transistors, a p type MOS transistor 20 for the specific RF circuit includes a p type source diffusion layer 22 and a p type drain diffusion layer 23 on a main surface of a silicon substrate 1 . Source and drain diffusion layers 22 and 23 include lightly doped drain (LDD) diffusion layers 24 and 25 , respectively, adjacent thereto. Furthermore between LDD diffusion layers 24 and 25 a channel doping layer 26 is formed for adjusting a threshold voltage Vth. Furthermore LDD diffusion layers 24 and 25 are surrounded by n + type pocket diffusion layers 27 and 28 formed by shallow ion injection. V th adjusting channel doping layer 26 and n + type pocket diffusion layers 27 and 28 are provided to improve the MOS transistor's basic characteristics, such as ON current characteristics and threshold voltage V th , to sufficiently eliminate source-drain current leakage.
[0039] Furthermore in a substrate region underlying p type MOS transistor 20 of the specific RF circuit a highly doped n well layer 21 is formed to extend in the direction of the depth of silicon substrate 1 from a pn junction interface corresponding to a bottom plane of source and drain diffusion layers 22 and 23 and also to a boundary between layers 22 and 23 and the substrate region. Furthermore, although not shown in the figure, a plurality of highly doped n type layers such as an n type punchthrough stopper layer, an n type isolation layer and an n type buried layer are formed, as required, in the substrate region underlying the pn junction interface. This highly doped n type layers are essential to currently used MOS transistors for example to prevent latch-up and reduce current leakage.
[0040] The specific RF circuit and the RF switch circuit include n type MOS transistors 10 and 30 , respectively, having n type source diffusion layers 12 and 32 , respectively, and n type drain diffusion layers 13 and 33 , respectively on a main surface of silicon substrate 1 . Source and drain diffusion layers 12 and 13 are adjacent to LDD diffusion layers 14 and 15 , respectively, and source and drain diffusion layers 32 and 33 are adjacent to LDD diffusion layers 34 and 35 , respectively. Furthermore between LDD diffusion layers 14 and 15 and between LDD diffusion layers 34 and 35 channel doping layers 16 and 36 are formed, respectively, for adjusting threshold voltage V th . Furthermore, LDD diffusion layers 14 and 15 , and 34 and 35 are surrounded by p + type pocket diffusion layers 17 and 18 , and 37 and 38 , respectively, formed by shallow ion injection.
[0041] With reference to FIG. 2, n type MOS transistors 10 and 30 , with the aforementioned LDD diffusion layers 14 and 15 , and 34 and 35 , threshold voltage V th adjusting channel doping layers 16 and 36 , and furthermore p + type pocket diffusion layers 17 and 18 , and 37 and 38 , have a channel region having an uneven dopant concentration. Furthermore, the channel region's dopant concentration, as seen in a direction parallel to a main surface of silicon substrate 1 , increases in a vicinity of a portion of source and drain diffusion layers 12 and 13 , and 32 and 33 , i.e., LDD diffusion layers 14 and 15 , and 34 and 35 . V th adjusting channel doping layers 16 and 36 , and n + type pocket diffusion layers 17 and 18 , and 37 and 38 are formed to enhance the MOS transistors' basic characteristics (such as ON current characteristics and threshold voltage Vth) and sufficiently eliminate source-drain current leakage. Note that p type MOS transistor 20 also has a channel region having a similar, uneven dopant concentration profile, although different in conductivity.
[0042] Furthermore in a substrate region 1 a underlying p type MOS transistor 10 of the specific RF circuit a highly doped p well layer 11 is formed to extend in the direction of the depth of silicon substrate 1 from a pn junction interface corresponding to a bottom plane of source and drain diffusion layers 12 and 13 and also to a boundary between layers 12 and 13 and substrate region 1 a . Furthermore, although not shown in the figure, a plurality of highly doped p type layers such as a p type punchthrough stopper layer and a p type isolation layer are formed, as required, in substrate region 1 a underlying the pn junction interface. These highly doped p type layers are essential to currently used MOS transistors for example to prevent latch-up and reduce current leakage.
[0043] In contrast, n type MOS transistor 30 of the RF switch circuit overlies a substrate region 1 b free of any highly doped, p type well layer extending from a pn junction interface in the direction of the depth of silicon substrate 1 . Furthermore, a p type isolation layer, a p type punchthrough stopper layer and any other similar, highly doped p type layer are also absent. As such, substrate region 1 b has the initial dopant concentration of silicon substrate 1 . As such, the dopant concentration of substrate region 1 b immediately underlying an interface between source and drain diffusion layers 32 and 33 and substrate region 1 b of n type MOS transistor 30 of the RF switch circuit, is lower than that of substrate region 1 a immediately underlying an interface between source and drain diffusion layers 12 and 13 and substrate region 1 a of n type MOS transistor 10 of the specific RF circuit.
[0044] Fabrication
[0045] Reference will now be made to FIGS. 3 - 8 to describe a process for fabricating the silicon semiconductor integrated circuit of the present embodiment. The silicon semiconductor integrated circuit in the present embodiment is fabricated in accordance with a basic MOS transistor process flow. More specifically, as shown in FIG. 3, silicon substrate 1 initially has a main surface provided with an element isolation film 2 . Then, as shown in FIG. 4, ion injection is provided for forming p type MOS transistor 20 . Then, as shown in FIGS. 5 - 7 , ion injection is provided for forming n type MOS transistors 10 and 30 . Furthermore, as shown in FIG. 8, a gate electrode 4 has a side wall provided with a sidewall 5 to complete a semiconductor integrated circuit configured as shown in FIG. 1.
[0046] Note, however, that to fabricate the semiconductor integrated circuit of the present embodiment, it is necessary to use an additional photomask to selectively, differently configure a substrate region underlying the n type MOS transistor of the specific RF circuit and that underlying the n type MOS transistor of the RF switch circuit. More specifically, n type MOS transistor 30 of the RF switch circuit overlies substrate region 1 b free of any highly doped, p type layer. To achieve this, in forming a plurality of highly doped, p type layers of n type MOS transistor 10 of the specific RF circuit such as p well layer 11 , a p type punchthrough stopper layer and a p type isolation layer a region of silicon substrate 1 that is to be served for n type MOS transistor 30 of the RF switch circuit is covered with photoresist 7 (see FIG. 5). A highly doped, p type layer is thus formed selectively only under n type MOS transistor 10 of the specific RF circuit, while the layer is not formed under n type MOS transistor 30 of the RF switch circuit.
[0047] Result of Simulation
[0048] Reference will now be made to FIGS. 9 and 10 to describe a result of a simulation of electrical characteristics of the silicon semiconductor integrated circuit configured as described above. As has been described above, the n type MOS transistor of the RF switch circuit overlies a substrate region free of any highly doped, p type layer, and, as is apparent from FIG. 9, for the n type MOS transistor of the RF switch circuit a p type dopant concentration immediately under a pn junction interface is significantly smaller than for the n type MOS transistor of the specific RF circuit. More specifically, the n type MOS transistor of the specific RF circuit overlies a p type punchthrough stopper layer, a p type isolation layer, a p well layer or the like and under the pn junction interface a dopant concentration of no less than 10 17 cm −3 is provided, whereas for the n type MOS transistor of the RF switch circuit a dopant concentration of approximately 10 15 cm −3 is provided. This presumably contributes to a larger width, as seen in the direction of the depth of the silicon substrate, of a depletion layer introduced at the pn junction of the n type MOS transistor of the RF switch circuit that is biased than the n type MOS transistor of the specific RF circuit that is biased.
[0049] Furthermore, in FIG. 10, as a region having a high electric field may be considered a region of a depletion layer, presumably for the n type MOS transistor of the specific RF circuit a depletion layer in the vicinity of the pn junction interface would be introduced with a significantly small width, whereas for the n type MOS transistor of the RF switch circuit a depletion layer would extend much deeper than the pn junction interface. More specifically, in a semiconductor integrated circuit designed to have a dopant concentration profile as shown in FIG. 9, presumably for the n type MOS transistor of the specific RF circuit a depletion layer would extend only to a depth of approximately 0.1 μm as measured from the pn junction interface, whereas for the n type MOS transistor of the RF switch circuit a depletion layer would extend as deep as approximately 1 μm.
[0050] Function and Effect
[0051] A silicon semiconductor integrated circuit configured as described above can provide a larger width of a depletion layer extending downward from a pn junction of a MOS transistor of an RF switch circuit that is biased than an n type MOS transistor of another, specific RF circuit that is biased. As such, the former transistor's source/drain junction capacitance Cd can significantly be reduced and accordingly also in an RF range its impedance can sufficiently be increased. This can eliminate a loss of an RF signal that is attributed to a small source/drain junction capacitance Cd of the MOS transistor of the RF switch circuit. An RF semiconductor device with a satisfactory switch function can thus be provided.
[0052] Furthermore, as a p type dopant concentration immediately under a pn junction interface of the source and drain is reduced, a resistance R si of a silicon substrate in a grounding path connected to capacitance C d is also increased and an impedance corresponding to C d and R si together serving as a grounding path that are added together is increased, and a loss of an RF signal in the MOS transistor of the RF switch circuit is further reduced. A high-performance, RF silicon semiconductor device that has not conventionally been implemented for an RF range such as no less than 5 GHz, can thus be provided.
[0053] Note that providing an uneven, lateral, one-dimension dopant concentration laterally traversing source and drain diffusion layers of the n type MOS transistor of the RF switch circuit to form an effectively heavily doped, p type region in a portion laterally adjacent to a pn junction provided by a p + pocket diffusion layer, ensures preventing a depletion layer from laterally extending and also preventing current leakage attributed to puncthrough.
[0054] Prototype
[0055] A prototype device was fabricated and had its electrical characteristics measured, as represented in FIGS. 11 and 12. FIG. 11 represents a result of an estimation of a discrete, n type MOS transistor's source and drain passage characteristics by S parameter RF characteristics estimation. Note that FIG. 11 also represents a result of a measurement of an n type MOS transistor of an RF switch circuit conventionally configured for reference. As shown in FIG. 11, it can be understood that the n type MOS transistor of the RF switch circuit conventionally configured provides a significantly increased insertion loss for an RF range, whereas that of the RF switch circuit in accordance with the present invention provides a hardly increased insertion loss for the RF range.
[0056] [0056]FIG. 12 represents S parameter characteristics S 11 of the n type MOS transistor of the RF switch circuit as conventional and S parameter characteristics S 11 of the n type MOS transistor of the RF switch circuit in accordance with the present invention, as represented in a Smith chart. It can be understood that the n type MOS transistor of the RF switch circuit as conventional provides an arc moving on the chart, starting at the chart's center (50 Ω) and proceeding round in a right downward direction as frequency increases. This indicates that a large source/drain junction capacitance component exists. In contrast, the n type MOS transistor of the RF switch circuit in the present invention does not provide a movement in an arc starting at the chart's center (50 Ω) and proceeding round in the right downward direction. It hardly provides a movement away from the chart's center as frequency increases. That is, it can be understood that junction capacitance is significantly reduced.
[0057] It can thus be understood that the n type MOS transistor of the RF switch circuit in the present invention can exhibit significantly satisfactory RF characteristics. However, its source and drain diffusion layer's bottom surface or a pn junction interface overlies a low p type dopant concentration, and punchthrough characteristics between the source and drain diffusion layers of the MOS transistor may be impaired. FIG. 13 represents a result of a measurement of breakdown voltage between source-drain diffusion layers of the n type MOS transistor of the RF switch circuit of the present embodiment. As can be apparent from the figure, the configuration in the present embodiment provides worse breakdown voltage characteristics than a conventional configuration. More specifically, for a most important power supply voltage (of 1.8V for this MOS transistor) a current leakage in a device used as a switch and having a gate width of approximately 200 μm has a maximal value of approximately 300 nA, which is no less than 100 times a value (of approximately 2 nA at its maximum) of an MOS transistor of another, specific RF circuit.
[0058] For typical logic circuits, an MOS transistor with such a large current leakage cannot be used, since a logic circuit uses a large number of MOS transistors in total, and in total an enormous current would be consumed and reduced power consumption cannot be achieved. An RF switch circuit, as will be described hereinafter, employs as few as two or four devices having a gate width of approximately 200 μm, and a maximal current leakage of 200 nA per MOS transistor is sufficiently acceptable. As such, forming an RF switch circuit of the MOS transistor structured as above, as described in the present embodiment, is not disadvantageous. On the contrary, it can be understood that an effect obtained therefrom is more enormous.
[0059] Second Embodiment
[0060] Reference will now be made to FIG. 14 to describe a second embodiment of the present invention. In the present embodiment a semiconductor integrated circuit is configured similarly as described in the first embodiment, although an isolation film 2 a adjacent to an active region of n type MOS transistor 30 of an RF switch circuit has a width larger than a minimal design rule (a design rule applied in another, specific RF circuit). This can prevent an isolation film from having a reduced device isolating capability attributed to absence of ion injection for isolation and hence prevent current leakage between adjacent devices from increasing. A circuit using an n type MOS transistor free of ion injection for isolation, as assumed in the present invention, includes an RF switch circuit. The circuit employs no more than several MOS transistors. As such, if an isolating oxide film is increased in width, it does not result in a significantly increased chip area or affect the cost.
[0061] Third Embodiment
[0062] Reference will now be made to FIG. 15 to describe a third embodiment of the present invention. In the present embodiment a semiconductor integrated circuit is configured similarly as described in the first embodiment, although isolation film 2 adjacent to an active region of n type MOS transistor 30 of an RF switch circuit overlies a low doped diffusion layer 9 . Thus, the dopant concentration under isolation film 2 adjacent to n type MOS transistor 30 of the RF switch circuit is lower than that under an isolation film adjacent to an active region of an n type MOS transistor of another, specific RF circuit. This can prevent an isolation film from having a reduced device isolating capability attributed to absence of ion injection for isolation in a substrate region, i.e., prevent current leakage between adjacent devices from increasing. Furthermore, the present embodiment allows a chip area to be smaller than the second embodiment does.
[0063] Exemplary Application
[0064] In the present exemplary application the MOS transistor of the RF switch circuit as described in any of the first to third embodiments is used to fabricate an SPDT switch as shown in FIG. 16. N type MOS transistor 30 that is used preferably has a gate width of approximately 10 μm to 1 mm and desirably has a gate length in accordance with a minimal design rule to reduce ON resistance R on . Forming each device's connection line and each terminal's connection line of a transmission line exhibiting a 50 Ω characteristics impedance for an operating frequency, allows more preferable characteristics.
[0065] As such, a p type dopant concentration under a pn junction of source/drain of the n type MOS transistor forming the RF switch circuit, is reduced. A pn junction depletion layer significantly extends and a source/drain junction capacitance significantly decreases. This can significantly reduce a loss of an RF signal passing through the source/drain junction capacitance of the transistor of the RF switch circuit that is attributed to the silicon substrate's resistance and significantly reduce insertion loss, one of the most important RF characteristics of the RF switch circuit.
[0066] Furthermore the MOS transistor of the RF switch circuit as described in any of the first to third embodiments is used to fabricate an SPDT switch as shown in FIG. 17. N type MOS transistor 30 that is used preferably has a gate width of approximately 10 μm to 1 mm and desirably has a gate length in accordance with a minimal design rule to reduce ON resistance R on , as described above. Forming each device's connection line and each terminal's connection line of a transmission line exhibiting a 50 Ω characteristics impedance for an operating frequency, allows more preferable characteristics.
[0067] As such, a p type dopant concentration under a pn junction of source/drain of the n type MOS transistor forming the RF switch circuit, is reduced. A pn junction depletion layer significantly extends and a source/drain junction capacitance significantly decreases. This can significantly reduce a loss of an RF signal passing through the source/drain junction capacitance of the transistor of the RF switch circuit that is attributed to the silicon substrate's resistance and significantly reduce insertion loss, one of the most important RF characteristics of the RF switch circuit.
[0068] Essentially, a series-parallel SPDT switch having an effect improving isolation characteristics is preferably used as a switch circuit. In effect, however, it has been inapplicable, since series-parallel type has conventionally used a larger number of MOS transistors than series type and further increased an increased insertion loss attributed to a source/drain junction capacitance. The present invention can eliminate the increased insertion loss attributed to a source/drain junction capacitance. Accordingly, a series-parallel SPDT switch allowing isolation characteristics to be improved can be used and an SPDT switch having satisfactory RF characteristics can be provided.
[0069] In the above description an RF switch circuit has employed an MOS transistor overlying a substrate region free of injection for isolation to have a low concentration. However, it is not limited thereto. The present invention lies in providing a lower dopant concentration in a substrate region of an MOS transistor of an RF switch circuit than in an MOS transistor of another, specific RF circuit, and it is not limited to any particular level of concentration. As such, for example, the MOS transistor of the RF switch circuit may have its well layer, isolation layer, punchthrough stopper layer and the like formed with a smaller dosage than the MOS transistor of the specific RF circuit to achieve a reduced concentration of a substrate region of the MOS transistor of the RF switch circuit.
[0070] Furthermore, while in the first embodiment a gate oxide film of the MOS transistor of the specific RF circuit and that of the MOS transistor of the RF switch circuit have simultaneously been formed by way of example, they may be provided separately. More specifically, these gate oxide films may be different in thickness. Desirably, however, they are simultaneously provided to simplify the fabrication process.
[0071] Furthermore, desirably, the MOS transistor of the specific RF circuit and that of the RF switch circuit have their respective gates with their respective lengths each set to be a dimension in accordance with a minimal design rule to allow the MOS transistors to have the most excellent gate characteristics.
[0072] Note that in general, semiconductor integrated circuits of this type often employ a p type silicon substrate and the RF switch circuits often employ an n type MOS transistor. Partially, however, a p type MOS transistor can be used and the present invention is also applicable thereto.
[0073] Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims. | A semiconductor integrated circuit device includes a silicon substrate having a first region and a second region identical in conductivity to said first region and having a lower dopant concentration than said first region, a second MOS transistor formed on a main surface of said second region and configuring a radio frequency switch circuit switching on/off an input and output of a radio frequency signal, and a first MOS transistor formed on a main surface of said first region and configuring a radio frequency circuit other than said radio frequency switch circuit. There can be provided a high performance, highly reliable semiconductor integrated circuit with an RF switch circuit provided on a silicon substrate by SOPing. | 7 |
BACKGROUND OF THE INVENTION
Conventional clothes washing machines are of two basic types: a vertical axis, top loading machine and a horizontal axis front loading machine. While front loading machines are generally more economical with respect to water consumption and electrical usage, the top loading machines typically provide easier access. Both types of washing machines include a perforated basket which holds the clothes or articles being washed. In the front loading machine, the clothes are tumbled in the wash water while the basket rotates. In a top loading machines, an oscillating or rotating agitator mixes the clothes and articles in the wash water while the basket remains substantially stationary. At the completion of the wash cycle in either machine, the basket is rotated at a high RPM to extract the wash water from the basket and the clothes therein.
An objective of the present invention is the provision of an improved top loading washing machine.
A further objective is to provide a top loading washer having rotatable agitators/lifters within a washing basket.
A further objective is to provide a novel drive system for rotating the agitators/lifters within a washing basket.
A further objective is to provide a drive system for agitators within a washing basket wherein the drive system is at least partially bathed in washing fluid.
Another objective of the present invention is the provision of a top loading washing machine having low water usage, yet excellent mechanical washing action.
Another objective of the present invention is the provision of a top loading washing machine having a simple and durable construction.
A further objective of the present invention is the provision of an improved top loading, washing machine which is economical to manufacture and to operate.
SUMMARY OF THE INVENTION
The foregoing objects may be achieved by a washing machine having a cabinet with a top opening. A wash basket is mounted within the cabinet for rotation about a wash basket axis. The wash basket has an upwardly facing access opening through which clothes may be loaded and unloaded. At least a first agitator/lifter is mounted in the basket for rotation about an agitator axis which is at an angle different from the angle of the wash basket axis. A drive motor is mounted to the cabinet. A drive mechanism interconnects the motor, the wash basket, and the first agitator for rotating the first agitator about the first agitator axis when the wash basket is held against rotation about its wash basket axis.
It is preferred that a second agitator also be mounted within the wash basket and that it also be driven by the drive mechanism.
A tub at least partially surrounds the wash basket and contains washing fluid. The drive mechanism preferably is at least partially submerged in and bathed by the washing fluid.
While the shape of the washing basket and tub may vary without detracting from the invention, it is preferable that the washing basket and the tub be spherical, and that the agitators each have a concave surface and a convex surface, with the convex surfaces nesting against the spherical walls of the washing basket.
BRIEF DESCRIPTION OF THE FIGURES OF THE DRAWINGS
FIG. 1 is a perspective view of the washing machine of the present invention.
FIG. 2 is a sectional view taken generally along line 2 — 2 of FIG. 1 .
FIG. 3 is a sectional view taken generally along line 3 — 3 of FIG. 2 .
FIG. 4 is an enlarged detailed view of the gear drive mechanism for the present invention.
FIG. 5 is an enlarged detailed view taken generally along line 5 — 5 of FIG. 2 .
FIG. 6 is a pictorial view showing the gear drive assembly and one agitator pan.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings the numeral 10 generally designates the washing machine of the present invention. Washing machine 10 includes a cabinet 12 , a control panel 14 , an access opening 15 (FIG. 2 ), and a door 16 which is hinged to move from an open to a closed position over the access opening 15 .
Mounted within the lower end of the cabinet 12 on a web 23 is a reversible drive motor 18 of conventional construction. Motor 18 has an output shaft 20 which extends upwardly through a bearing 22 in the web 23 . In this embodiment, motor 18 is attached to the web 23 by brackets 24 . Shaft 20 extends upwardly through a clutch 26 shown schematically in FIGS. 2 and 4. Clutch 26 is adapted to respond to rotation of the shaft 20 in a first direction to drive a hub 34 which is connected to a spherically shaped basket 40 . Rotation of the shaft 20 in the opposite direction disengages the clutch 26 and permits the shaft 20 to rotate independently of hub 34 .
As best shown in FIGS. 2 and 4, a tub 28 includes at its lower end a basin 30 for holding washing fluid. Extending upwardly from basin 30 is a spherically shaped lower tub portion 31 . The tub 28 extends upwardly to the top of basket 40 and terminates at an upper edge 32 . A tub cover 33 is attached to the upper edge 32 and extends inwardly over a portion of the top opening 41 of basket 40 . The tub cover 33 is cooperable with access opening 15 for providing a path into basket 40 .
Hub 34 includes a central bore 36 which receives output shaft 20 . Output shaft 20 is attached at its upper end to a drive gear 38 .
Hub 34 extends through the basin 30 by way of a rotary seal arrangement shown schemactially at 43 in FIGS. 2 and 4 and is attached to the basket 40 which includes a spherical portion 42 and a gear box portion 44 in its lower end. Extending over the top of the gear box portion 44 is a curved wall 46 which forms an extension of the spherically shaped walls of spherical portion 42 . Curved wall 46 includes a first gear hole 48 and a second gear hole 50 therein. The space below the curved wall 46 comprises a gear box chamber 52 for housing the gear drive to be described hereafter.
Basket 40 includes a plurality of perforations in its spherical shaped walls 42 for permitting fluid communication between the interior of basket 40 and the tub 28 . Thus, as fluid is introduced into the basket 40 , the fluid flows through apertures 54 and enters the tub 28 also. As further depicted in FIG. 2, the web 23 , drive motor 18 and the washing assembly are shown suspended from the inside of cabinet 10 by a conventional hung strut suspension system 25 which is of known construction and does not comprise part of the instant invention.
Agitator/lifter pans 56 , 58 each include a circular peripheral rim 60 and a circular pan gear 62 which extends circumferentially around the back side of the rim 60 .
Agitator/lifter pans 56 , 58 are each rotatably mounted to the basket 40 by a pan mount assembly 64 which is shown in enlarged detail in FIG. 5 . The spherical portion 42 of basket 40 includes an opening 66 in each of the opposite sides thereof. Opening 66 is surrounded by an annular shoulder 68 . A plug body 70 includes a head 72 and a shank 74 . Spring fingers 76 extend radially outwardly from the shank 74 and are adapted to move yieldably inwardly. The plug 70 is inserted through the opening 66 in the basket wall 42 . During insertion spring fingers 76 cam radially inwardly and slip past the annular shoulders 68 surrounding opening 66 . After the spring fingers clear the annular shoulder 68 they spring outwardly and retain the plug 70 within the opening 66 . Shank 74 of plug body 70 includes a screw receptacle 78 .
Agitator/lifter pans 56 and 58 are each provided with a cylindrical outer sleeve 80 in which is inserted a bearing boss 82 . Inserted within boss 82 is a locking tube 84 having a head 86 and a web 88 . A screw 90 extends through web 88 and is threaded into the screw receptacle 78 of plug 70 . This attaches the agitator pans 56 , 58 to the side walls 42 of basket 40 , while at the same time permitting the agitator pans 56 , 58 to rotate about the cylindrical axes of the sleeves 80 .
Referring to FIGS. 4 and 6, a gear assembly 92 is housed within the gear box chamber 52 and includes a first driven gear 94 which directly engages the annular teeth of the drive gear 38 . First driven gear 94 is connected to a first pan gear 96 by a gear shaft 98 . An idler gear 100 is also directly driven by drive gear 38 . Idler gear 100 , in turn, engages gear 104 which has a second pan drive gear 106 on its upper surface.
In operation, shaft 20 drives gear 38 in a clockwise direction indicated by arrow 108 (FIG. 6 ). This rotates gears 94 , 100 in the directions shown by arrows 110 , 114 respectively. Rotation of gear 94 causes similar rotation of first pan gear 96 in the direction indicated by arrow 112 . First pan gear 96 engages the teeth of the circumferential gear 62 on the back of peripheral rim 60 on agitator pan 56 . This causes rotation of agitator pan 56 about its axis formed by the pan mount assembly 64 .
Rotation of idler gear 100 causes rotation of gear 104 in the direction indicated by arrow 118 . This also causes rotation of second pan gear 106 in the direction indicated by arrow 120 . In this embodiment, the rotational axis of agitator pans 56 and 58 are each located 60 degrees from the vertical rotational axis of the drive gear 38 and opposite one another. Because of this angular disposition, the rotational planes of the circumferential gears 62 and the first and second pan gears 96 , 106 operate at an acute angle with respect to each other.
It should be noted that first and second pan gears 96 , 106 , rotate in opposite directions, thereby causing the agitator pans 56 , 58 to also rotate in opposite directions as indicated by the arrows 122 , 124 in FIG. 3 . Alternately, gearing can be provided to cause agitator pans 56 , 58 to rotate in the same direction if desired.
All the gears in gear assembly 92 are preferably formed of a plastic material so that they can be bathed within the washing fluid within basin 30 of tub 28 and within the gear box chamber 52 of basket 40 . Various types of noncorrosive materials may be used, but the preferred material is a thermoplastic polymer sold under the trademark Carilon by Shell Chemical Company.
As can be seen in FIG. 2 the water or washing fluid level 126 is at approximately the level of the pan mount assemblies 64 . The rotation of the two agitator pans 56 , 58 creates a tumbling action of the fabrics 134 being washed within the washing basket 40 . This tumbling action is facilitated by ribs 128 which are formed on the interior concave surfaces 130 of the agitator pans 56 , 58 . The back surfaces of agitator pans 56 , 58 are convex. While they do not conform precisely to the interior spherical surface of the basket 40 they are shaped to nest against this interior surface with the annular rims 60 of the pans 56 , 58 bearing against the curved spherical wall 42 of basket 40 . The annular rim 60 is provided with a seal 132 which prevents the fabrics or clothing from becoming entangled with the first and second pan gears 96 , 106 which protrude upwardly through the first and second gear holes 48 , 50 in the curved wall portion 46 , and which engage the circumferential gears 62 on the back sides of rims 60 of the agitator pans 56 , 58 .
The present invention has been found to provide superior washing capabilities over prior art washing machines. The tumbling action provided by agitator pans 56 , 58 is a gentle action that minimizes damage and wear to delicate fabrics. Furthermore, the ribs 128 on the interiors of agitator pans 56 , 58 cause a lifting of the washing fluid and improve the cleaning of the fabrics within the basket 40 .
The gear assembly 92 for driving the pans 56 , 58 is submerged within the washing fluid, and is bathed by the washing fluid throughout the operation of the device.
After the washing cycle has been completed, motor 18 is reversed, and the reverse rotation of shaft 20 causes the clutch 26 to engage with the hub 34 , thereby causing the basket 40 to rotate for its spin cycle. During the spin cycle the washing fluid passes outwardly through apertures 54 due to centrifugal force. The fluid within tub 28 is drained away.
In the drawings and specification there has been set forth a preferred embodiment of the invention, and although specific terms are employed, these are used in a generic and descriptive sense only and not for purposes of limitation. Changes in the form and the proportion of parts as well as in the substitution of equivalents are contemplated as circumstances may suggest or render expedient without departing from the spirit or scope of the invention as further defined in the following claims. | A washing machine includes a cabinet with an opening. A wash basket is mounted within the cabinet for rotation about a wash basket axis, and includes an access opening through which clothes may be loaded and unloaded. At least one agitator is mounted within the basket for rotation about an agitator axis which is at an angle different from the angle of the wash basket axis. A drive mechanism bathed by washing fluid interconnects a drive motor, the wash basket, and the agitator for rotating the agitator about its rotational axis. | 3 |
BACKGROUND OF THE INVENTION
The present invention concerns a process for the preparation of aminophenols by the hydroxylation, in liquid superacid medium utilizing hydrogen peroxide, of certain aromatic amines.
The invention allows the introduction of a phenol function on the aromatic ring of the amine in the ortho, meta, and para positions in relation to the amine group, without oxidation of the nitrogen of the amine functional group. The proportion of the meta-aminophenol formed is predominant.
French Pat. No. 82 10644 describes a process for the hydroxylation of anilides; i.e., amides derived from aniline, with hydrogen peroxide in a superacid medium. It is particularly surprising that an analogous process can be applied to unprotected anilines, since prior art very clearly teaches that peroxide compounds (hydrogen peroxide, organic peracids, hydroperoxides, diacyl peroxides) in general attack the nitrogen of the amine function with the formation of hydroxylamine, amine oxide, nitroso derivatives, azo derivatives, azoxy derivatives or polymers. Sometimes an attack on the alkyl groups borne by the nitrogen of secondary and tertiary aromatic amines is observed involving dealkylation reactions or the formation of imines.
These different modes of action of peroxide compounds on aromatic amines are described in the following references:
B. C. CHALLIS and A. R. BUTLER, in "The Chemistry of the Amino Group" (PATAI), p. 320-338, Interscience Publishers, New York, 1968;
M. HEDAYATULLAH, Bull. Soc. Chim. France, 1972, p. 2957-2974; and
J. P. SCHIRMANN and S. Y. DELAVARENNE, "Hydrogen Peroxide in Organic Chemistry", chapter VII, p. 147-156, EDI Paris, 1979.
In the special case of N,N-dialkylanilines, oxidation by peroxydisulfate ions, known under the name of BOYLAND-SIMS reaction, leads to the introduction on the aromatic ring of a sulfate group, later hydrolyzable into a phenol group. This introduction essentially takes place in the ortho position with respect to the amine group, with the para isomer forming in significant proportions only when the two ortho positions are blocked. No meta isomer is formed. This BOYLAND-SIMS reaction has been studied by E. J. BEHRMAN and D. M. BEHRMAN, J. Org. Chem., 43, No. 23, p. 4551-4552 (1978).
SUMMARY OF THE INVENTION
It has now been surprisingly found that aminophenols can be prepared without attack on the amino nitrogen to form undesired products, such as imines.
Briefly stated, the present invention comprises a process for the preparation of aminophenols with an increased proportion of the meta isomer thereof comprising reacting hydrogen peroxide in a superacid liquid medium with an aromatic amine of the formula: ##STR1## in which R 1 and R 2 represent either hydrogen atoms, or a C 1 -C 8 alkyl radical at a temperature of from about -50° C. to 0° C. for a time sufficient to form the aminophenols.
DETAILED DESCRIPTION
According to the present invention, the hydroxylation on the aromatic ring of free amines, yielding large proportions of meta isomers, is achieved by causing hydrogen peroxide to act at low temperatures on the desired amine in a liquid superacid medium.
This liquid superacid medium consists of products which, on HAMMETT's logarithmic scale, have acidities reaching about -25. By way of comparison, 100% sulfuric acid has an acidity of -11 and anhydrous hydrofluoric acid has an acidicity of -10. The liquid superacids used thus have acidities up to 10 14 times higher than those of the customary strong mineral acids. Examples of liquid superacids utilizable in the process of the invention are "magic acid" FSO 3 H-SbF 5 , fluoroantimonic acid HF-SbF 5 , the complexes of trifluoromethane sulfonic acid with antimony pentafluoride CF 3 SO 3 H-SbF 5 , and the complex of hydrofluoric acid with boron trifluoride HF-BF 3 .
The hydrogen peroxide is utilized in the form of commercial aqueous solutions, whose titer can go from 20% to 98% by weight. The commercial solution of 70% by weight of H 2 O 2 is preferably used. The molar ratio of hydrogen peroxide to the substrate to be hydroxylated is generally between 1 and 2.
The proportion of superacid in relation to the aromatic amine can vary within wide limits. Generally, the proportion of superacid increases with the degree of dilution of the aqueous solution of the hydrogen peroxide. With a 70% solution of hydrogen peroxide by weight, from 4 to 20 milliliters of superacid per millimole of substrate are customarily used.
The reaction proceeds at temperatures from about -50° C. to about 0° C., at atmospheric pressure or under pressures exceeding atmospheric pressure, especially when the HF-BF 3 complexes are used. The duration of the reaction is from several minutes to one hour.
The general operating method followed in order to implement the process of the invention is very simple; the liquid superacid, the aromatic amine, and the hydrogen peroxide are successively introduced into a container made of poly(tetrafluoroethylene), or of stainless steel when operating with the HF-BF 3 complexes, equipped with a magnetic agitation apparatus and cooled to the desired temperature. The mixture is kept under agitation for the desired time at the selected temperature. It is then poured on a mixture of water, ice, and sodium bicarbonate. After neutralization, the solution is extracted several times with a low molecular weight organic solvent, such as diethyl ether. After evaporation of the solvent of extraction, the crude product is chromatographed on a silica gel by using as the eluent an organic solvent or a mixture of organic solvents making possible the separation of the reaction products.
According to a variation of this general operating method, one can introduce the hydrogen peroxide into the superacid prior to the substrate to be hydroxylated. According to other variations suitable especially for the HF-BF 3 mixtures, one introduces into the reactor first the substrate, then the superacid and the hydrogen peroxide, or the substrate, then the hydrogen peroxide and the superacid.
The invention will be further illustrated in conjunction with the following examples, which are set forth for purposes of illustration only and not by way of limitation.
EXAMPLE 1
Example 1 exemplifies the hydroxylation of aniline in HF-SbF 5 medium.
(a) According to the general operating method, a mixture of 17.5 ml of anhydrous hydrofluoric acid and 2.5 ml of antimony pentafluoride (molar ratio of SbF 5 /HF=0.04) is cooled to -40° C. To this mixture 4 millimoles of aniline are successively added and 4 millimoles of hydrogen peroxide in the form of a 70% aqueous solution by weight. The reaction mixture is kept under agitation for 15 minutes at -40° C.
After treatment, the crude product obtained, weighing 320 mg, is chromatographed on a silica gel under nitrogen pressure. A 50/50 mixture by volume of hexane and ethyl acetate successively elutes the unconverted aniline, 2-aminophenol, 3-aminophenol, and 4-aminophenol. The structure of the products formed is determined by physical and spectroscopic characteristics (nuclear magnetic resonance, infrared, and mass spectrum) and also from identification with known products.
(b) The above test is repeated, but at a temperature of -20° C. and by using a molar ratio of H 2 O 2 /substrate of 1.5 instead of 1.0.
The quantitative results of these two tests are given in Table I.
TABLE I______________________________________ Relative ProportionsDegree of of the IsomersConversion Yield of (Percentages)Test of the Aniline Aminophenols ortho meta para______________________________________1a 68% 40% 35 57 81b 95% 70.5% 29 51 20______________________________________
EXAMPLE 2
Example 2 exemplifies the hydroxylation of N,N-dimethylaniline in HF-SbF 5 medium with 70% hydrogen peroxide.
A mixture of 15.75 ml anhydrous hydrofluoric acid and 2.25 ml antimony pentafluoride (molar ratio of SbF 5 /HF=0.04) is cooled to -20° C. and to this mixture 4 millimoles of N,N-dimethylaniline are successively added and 4 millimoles of hydrogen peroxide in the form of an aqueous solution of 70% by weight.
The reaction mixture is kept at -20° C. under agitation for 15 minutes. After treatment, 540 mg of crude product are obtained which are chromatographed on silica gel under nitrogen pressure. A 70/30 mixture by volume of hexane and ethyl acetate makes it possible to elute successively:
unconverted N,N-dimethylaniline (12%)
2-hydroxy N,N-dimethylaniline (14%)
3-hydroxy N,N-dimethylaniline (44%)
4-hydroxy N,N-dimethylaniline (26%)
The relative proportions of the hydroxylated isomers are:
ortho: 17%
meta: 52%
para: 31%
Since the para isomer is difficult to identify by nuclear magnetic resonance of the proton, it has been characterized by the NMR spectrum of its acetyl derivative, obtained by the action of acetic anhydride.
EXAMPLE 3
Example 3 exemplifies the hydroxylation of N,N-diethylaniline in HF/SbF 5 medium.
(a) To a mixture of 15.75 ml of anhydrous hydrofluoric acid and 2.25 ml of antimony pentafluoride (molar ratio of SbF 5 /HF=0.04), cooled to -20° C., 4 millimoles of N,N-diethylaniline are successively added and 4.4 millimoles of hydrogen peroxide in the form of a 70% aqueous solution by weight. The reaction mixture is kept under agitation at -20° C. for 15 minutes.
After treatment, the crude product weighing 610 mg is chromatographed on silica gel. The 90/10 mixture by volume of hexane and diethyl ether elutes 390 mg of a mixture composed of unconverted N,N-diethylaniline (312 mg) and of 2-hydroxy-N,N-diethylaniline (78 mg). The determination of the two products present in the mixture is carried out by NMR of the proton.
The 70/30 mixture by volume of hexane and diethyl ether elutes 190 mg of a 3-hydroxy-N,N-diethylaniline.
Finally, the 60/40 mixtures by volume of hexane and diethyl ether elutes 22 mg of a mixture of two products which have not accurately been identified. However, the mass spectrum of the mixture causes a peak which corresponds to 4-hydroxy-N,N-diethylaniline.
(b) The above test is repeated, but by using a molar ratio of H 2 O 2 /substrate of 1.5 instead of 1.1.
In this test, the mixture of the two most polar products eluted by the 60/40 hexane/diethyl ether mixture weights 140 mg.
Table II summarizes the quantitative results of the two tests, 3a and 3b.
The yield of 4-hydroxy-N,N-diethylaniline, insufficiently identified, has not been shown.
TABLE II______________________________________Degreee of Conversion Yields ofof the Hydroxylated DerivativesTest N,N--diethylaniline ortho meta para______________________________________3a 48% 12% 29% --3b 87.5% 11% 49% --______________________________________
EXAMPLE 4
Example 4 exemplifies the hydroxylation of N-ethylaniline in HF-SbF 5 medium.
A mixture of 17.5 ml of anhydrous hydrofluoric acid and 2.5 ml of antimony pentafluoride (molar ratio of SbF 5 /HF=0.04) is cooled to -20° C. and to this mixture 4 millimoles of N-ethylaniline are successively added and 6 millimoles of hydrogen peroxide in the form of a 70% aqueous solution by weight.
The reaction duration under agitation at -20° C. is 15 minutes.
After treatment, 520 mg of crude product are obtained which are chromatographed on silica gel.
The 85/15 mixture by volume of hexane and diethyl ether elutes 23 mg (4.5%) of N-ethylaniline not having reacted.
The 70/30 mixture by volume of hexane and diethyl ether elutes 100 mg (18%) of 2-hydroxy N-ethylaniline.
The 65/35 mixture by volume of hexane and diethyl ether elutes 221 mg (40.5%) of 3-hydroxy-N-ethylaniline.
The 55/45 mixture by volume of hexane and diethyl ether elutes 90 mg (16.5%) of 4-hydroxy-N-ethylaniline.
The relative proportions of hydroxylated isomers thus are:
ortho: 24%
meta: 54%
para: 22%
EXAMPLE 5
Example 5 exemplifies the hydroxylation of N,N-dimethylaniline in HF-SbF 5 medium by 35% hydrogen peroxide.
(a) To a mixture of 17.5 ml of anhydrous hydrofluoric acid and 2.5 ml of antimony pentafluoride (molar ration of SbF 5 /HF=0.04), cooled to -20° C., 2 millimoles of N,N-dimethylaniline are successively added and 3 millimoles of hydrogen peroxide in the form of a 35% aqueous solution by weight.
After 15 minutes of reaction at -20° C. under agitation, the reaction mixture is treated in the usual manner.
240 mg of crude product are obtained, which are chromatographed on silica gel. The unconverted N,N-dimethylaniline is eluted by a 90/10 hexane/diethyl ether mixture by volume. The 2-hydroxy-N,N-dimethylaniline is eluted by an 80/20 mixture of the same solvents. The 70/30 mixture elutes the 3-hydroxy-N,N-dimethylaniline and the 55/45 mixture elutes the 4-hydroxy-N,N-dimethyl-aniline. A 45/55 mixture makes it possible to elute 15 mg of a more polar product which has not been identified.
(b) The preceding test is repeated, but by utilizing a mixture of 7.5 ml of hydrofluoric acid and 2.5 ml of antimony pentafluoride (molar ratio of SbF 5 /HF=0.09) and by placing into the reaction 3.4 millimoles of 35% hydrogen peroxide.
After treatment, 270 mg of crude product are obtained which are chromatographed as above. The 45/55 hexane/diethyl ether mixture elutes 25 mg of an unidentified product.
Table III gives the quantitative results of tests 5a and 5b.
TABLE III______________________________________ Yield ofDegree of Conversion Dimethyl- Relative Proportionsof the amino- of the IsomersTest N,N--dimethylaniline phenols ortho meta para______________________________________5a 54.5% 26.5% 11% 60.5% 28.5%5b 65% 57.5% 12% 63% 25%______________________________________
EXAMPLE 6
Example 6 exemplifies the hydroxylation of N,N-dimethylaniline in CF 3 SO 3 H-SbF 5 medium.
(a) A mixture of 6 ml of trifluoromethane sulfonic acid and of 3 ml of antimony pentafluoride (molar ratio SbF 5 /CF 3 SO 3 H=0.6) is homogenized at -20° C. and to this mixture 3 millimoles of hydrogen peroxide are successively added in the form of a 70% aqueous solution by weight and 2 millimoles of N,N-dimethylaniline. The reaction mixture is kept at -20° C. under agitation for 8 minutes.
After treatment, 125 mg of crude product are obtained. Chromatography of this product, carried out as in Example 5, makes it possible to obtain 40 mg (yield 14.5%) of 3-hydroxy-N,N-dimethylaniline and 40 mg (yield 14.5%) of 4-hydroxy-N,N-dimethylaniline.
(b) The preceding test is repeated, but by introducing the amine into the superacid medium prior to the hydrogen peroxide and by raising the reaction duration to 10 minutes. 160 mg of crude product are obtained. Chromatography makes it possible to recover 28% of unconverted N,N-dimethylaniline and to isolate 48 mg (yield 17.5%) of 3-hydroxy-N,N-dimethylaniline and 20 mg (yield 7.5%) of 4-hydroxy-N,N-dimethylaniline. The 45/55 hexane/diethyl ether mixture elutes 19 mg of an unidentified more polar product.
EXAMPLE 7
Example 7 exemplifies the hydroxylation of N,N-dimethylaniline in FSO 3 H-SbF 5 medium.
A mixture of 6 ml of fluorosulfuric acid and 3 ml of antimony pentafluoride (molar ratio of SbF 5 /FSO 3 H=0.4) is cooled to -20° C. and to this mixture 3 millimoles of hydrogen peroxide are successively added in the form of a 70% aqueous solution by weight and 2 millimoles of N,N-dimethylaniline. The reaction duration under agitation at -20° C. is 15 minutes.
After treatment, 160 mg of crude product are obtained which are filtered on silica gel. The 70/30 mixture by volume of hexane and diethyl ether elutes 62 mg (yield 22.5%) of 3-hydroxy-N,N-dimethylaniline, while the 55/45 mixture of the same solvents elutes 45 mg (yield 16.5% of 4-hydroxy-N,N-dimethylaniline. The remainer of the crude product is composed of unidentified polymer materials.
EXAMPLE 8
Example 8 exemplifies the hydroxylation of N,N-dimethylaniline in HF-BF 3 medium.
Into a container made of poly(tetrafluoroethylene) and cooled to -40° C., 15 ml of anhydrous hydrofluoric acid are poured, in which a stream of boron trifluoride is made to bubble for 15 minutes. Two millimoles of N,N-dimethylaniline are then added and then 2.2 millimoles of hydrogen peroxide (70% aqueous solution by weight). A stream of boron trifluoride is made to bubble again and the medium is kept under agitation at -40° C. for 20 minutes.
After treatment, 250 mg of crude product are obtained which is chromatographed on silica gel. The 85/15 mixture by volume of hexane/diethyl ether elutes the unconverted N,N-dimethylaniline (210 mg--87%). The 70/30 mixture of the same solvents elutes 16 mg (6%) of 3-hydroxy-N,N-dimethylaniline. Only less than 1% of the para-hydroxylated derivative has been formed.
While the invention has been described in connection with a preferred embodiment, it is not intended to limit the scope of the invention to the particular form set forth, but, on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims. | Process for the preparation of aminophenols with an increased proportion of the meta isomer comprising reacting hydrogen peroxide in a superacid liquid medium with anilines, N-alkylaniline, or N,N-dialkylanilines for a time and a temperature, ranging from about -50° C. to 0° C., sufficient to form the aminophenols. | 2 |
FIELD OF THE INVENTION
[0001] The present invention relates to a method for licensing RNC capacity, and in particular to a system for ensuring that Iub throughput does not exceed a licensed rate.
BACKGROUND TO THE INVENTION
[0002] Advances in computing and networking technology have led to the development of new and increasingly complex communications networks, Today, for example, systems such as the Universal Mobile Telecommunications System (UMTS) seek to provide mobile phones, personal computers, and other computing devices with wireless access to the Internet and other networks.
[0003] FIG. 1 is a schematic diagram of a UMTS network. As shown in FIG. 1 , a mobile radio network generally includes a set of base stations and base station controllers. In the UMTS, this network is called the UMTS Terrestrial Radio Access Network (UTRAN), a base station is called a Node B, and a base station controller is called a Radio Network Controller (RNC).
[0004] The UTRAN communicates both with mobile terminals, known as User Equipments (UE), via a Uu interface, and with a Core Network (CN) via an Iu interface. As shown in FIG. 1 , the RNCs are connected:
to the Node B via an Iub interface; to each other via an Iur interface; and to the Core Network CN via an Iu interface.
[0008] The core network CN typically includes equipment for performing circuit and packet switching. For example, the core network CN may include one or more mobile switching centres (MSCs) (not shown) for enabling communication over the public switched telephone network (PSTN). The core network CN may also include a gateway general packet radio service (GPRS) support node (GGSN) (not shown) for interfacing to external packet-based networks such as the Internet. The interface between the RNCs and the MSC is known as Iu-cs, and the interface between the RNCs and the GGSN is Iu-ps.
[0009] The resource allocation within the system is important to maintain the flow of traffic. It is typical for two parties (such as an operator and the seller of the RNC) to describe, in a “Service Level Agreement” (SLA), the conditions for flow rates across interfaces. For example, the SLA may indicate that the operator has bought 50 Mbps Iub-max capacity (i.e. he has agreed that the maximum throughput across the Iub should not exceed 50 Mbps). The seller of the RNC may well provide more Iub capacity than the required 50 Mbps, but the traffic must be limited below the agreed capacity. The SLA is thus not usually enforced by the limitations of the hardware. The preferred solution is to provide more powerful hardware and enforce the SLA using software.
[0010] In many cases there is no direct mapping between the SLA and the required hardware. For example, aggregate Iub throughput (Iub-max) may be sold, but each RNC is connected to several RBSs through the Iub transport network. When the Iub Transport Network is dimensioned for this throughput, then the total peak capacity of Iub must be larger than the licensed capacity, because of spatial variation of the traffic. At the same time, the sum throughput of the interfaces must also be limited to ensure that the license level is not exceeded. In addition, the Iub transport network is owned by the operator and can easily be upgraded. A specific software solution for this purpose is desirable to enforce the limit.
[0011] There are two ways of limiting the throughput of an interface: shaping and policing. In the case of shaping, buffering is used, and the serving rate of the buffer is set to the required maximal throughput. In the case of policing, the out-of-profile packets are dropped without any buffering.
[0012] Where shaping is used, the packet delay is increased by buffering when the traffic is saturated. Self-clocking protocols such as the Transmission Control Protocol (TCP) can react on this delay increase by rate reduction, and in this way resolve the congested situation. This buffering method is used in IP routers and is TCP friendly by nature.
[0013] In some situations buffering is not allowed, or extra buffering delays to the in-profile packets are not desirable. In these situations shaping cannot be used and the throughput must be limited by policing. Several policing methods exist: one example is the Committed Access Rate (CAR) method of Cisco.
[0014] It is desirable to license RNC capacity so that it can operate with more than one interface. This requires that the sum throughput of more than one interface should be limited. For example, if an operator has a license for 50 Mbps Iub capacity, but three 100 Mbps cards installed, the aggregate traffic should still be regulated below 50 Mbps. This requires a distributed RNC capacity licensing algorithm. The actual traffic on the involved interfaces must be measured. Action may then be taken, based on these measurements, to force the licensed capacity.
STATEMENT OF THE INVENTION
[0015] In accordance with one aspect of the present invention there is provided a method of controlling the rate of traffic flow through an Iub interface of a Radio Network Controller, the method comprising:
obtaining a licensed rate at the Radio Network Controller, the licensed rate defining the maximum throughput permitted through the Iub interface; measuring the rate of traffic flow through the Iub interface and all Iu interfaces of the Radio Network Controller; identifying the extent to which packet switched traffic flow through the Iub interface exceeds the licensed rate; and if the packet switched traffic flow through the Iub interface exceeds the licensed rate, dropping packets from traffic flow through the Iub interface to reduce the traffic flow to the licensed rate.
[0020] Since the total throughput (through the Iu interfaces as well as the Iub interface) is measured the RNC can determine the correct goal for the decrease in traffic. Preferably Iu-cs and Iu-ps traffic are distinguished in the measurement. The Radio Network Controller then preferably reduces traffic flow through the Iub interface by a factor
[0000]
max
(
1
,
Iub
-
allowedLevel
Iub
*
Iu
cs
+
Iu
ps
Iu
ps
)
[0000] determined by where Iub, Iu cs and Iu ps are Iub, Iu-cs and Iu-ps traffic throughput levels respectively and allowedLevel is the licensed rate.
[0021] The step of measuring the rate of traffic flow through the Iub and all Iu interfaces is preferably carried out at periodic measurement intervals. If the rate of traffic flow through the Iub interface drops below the licensed rate, packets may continue to be dropped from the traffic flow through the Iub interface to reduce the traffic flow for a predetermined number of measurement intervals. This helps prevent oscillation in the control loop.
[0022] The procedure for dropping packets are dropped from traffic flow through the Iub interface preferably involves a policing method based on a virtual buffer. Upper and lower limits may be defined for occupancy of the virtual buffer, the lower limit determined from a target rate based on the extent to which the traffic flow through the Iub interface exceeds the licensed rate.
[0023] Preferably the virtual buffer occupancy is set to the lower limit when a decision is made that traffic flow should be reduced. The virtual buffer occupancy may be increased whenever a packet is forwarded, the increase in occupancy corresponding to the size of the packet. The virtual buffer occupancy is preferably decreased from a timer pulse by a factor determined by the period of the timer pulse multiplied by the target rate.
[0024] The packet dropping decision is preferably based on a moving average for the virtual buffer occupancy, which is updated every time the virtual buffer occupancy changes. When a packet arrives at the Radio Network Controller, the packet is preferably forwarded if the moving average is smaller than the lower limit. The packet is preferably dropped if the moving average is larger than the upper limit. If the moving average is between the lower and upper limits, the packet is preferably dropped with a probability determined by the extent to which the moving average of the buffer occupancy is higher than the lower limit, although packets below a predetermined size (e.g. 200 bytes) are preferably dropped only if the moving average is larger than the upper limit.
[0025] Preferably the licensed rate obtained by the Radio Network Controller is modifiable by a capacity controller. The licensed rate may be obtained by the Radio Network Controller by subscribing to a licence key. For example,
[0026] In accordance with another aspect of the present invention there is provided a Radio Network Controller comprising:
a rate determining means for obtaining a licensed rate, the licensed rate defining the maximum throughput permitted through an Iub interface of the Radio Network Controller; a traffic flow rate measuring means for measuring the rate of traffic flow through the Iub interface and all Iu interfaces of the Radio Network Controller; a processing means for identifying the extent to which packet switched traffic flow through the Iub interface exceeds the licensed rate; and policing means for dropping packets from traffic flow through the Iub interface to reduce the traffic flow to the licensed rate if the packet switched traffic flow through the Iub interface exceeds the licensed rate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 is a schematic illustration of a UMTS network.
[0032] FIG. 2 is a schematic illustration of the subsystems of an RNC.
[0033] FIG. 3 illustrates a method for controlling traffic flow in line with a licensed throughput rate.
[0034] FIG. 4 is a flow chart illustrating the functionality of a central entity operating throughput licence control.
[0035] FIG. 5 illustrates the operations involved in dropping packets to reduce flow rate.
[0036] FIG. 6 is a schematic illustration of a virtual buffer procedure for dropping packets.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0037] FIG. 2 illustrates subsystems in a typical RNC 201 . It will be noted that the RNC includes at least one Dedicated Channel Subsystem (DCS) 202 . All of the traffic passing through the Iu and Iub interfaces passes through the DCS 202 . The RNC also includes at least one Packet Data Router (PDR) 203. Packet switched traffic (i.e. traffic passing through the Iu-ps interface) passes through the PDR 203 .
[0038] FIG. 3 illustrates a method usable in a situation where an operator has licensed a particular Iub capacity, but the sum of the available capacity is higher than the licensed capacity. A “central entity” 301 of the RNC is informed of the licensed capacity. The central entity can be thought of as a capacity mode of the RNC, and acts as a throughput licence control. The total traffic of all involved interfaces in both directions is measured via DCSs 302 , and this information is provided to the central entity 301 at predetermined measurement periods, e.g. once per second. The central entity 301 compares the licensed rate with the total traffic, and decides whether or not traffic reduction is required. If traffic reduction is required, the central entity orders each PDR 303 to decrease its traffic by a given percentage (identified as “decreaseFactor”) which is calculated from the measured traffic. Each PDR reduces traffic by policing, i.e. out-of-profile packets are dropped without any buffering, as explained above. Since there are no buffers in PDRs, only packet drop is possible.
[0039] In the central entity 301 , hysteresis (described below) is employed to reduce the oscillation in the control-loop (i.e. reduce the number of switch on/off regulation in PDRs). Furthermore, the central entity 301 continues to instruct the PDRs 303 to regulate their traffic until the total traffic has been below the licensed level for several (e.g. 5) measurement periods. This also reduces the oscillation in the control-loop.
[0040] Thus, once per measurement period, the central entity receives from the DCSs the measured throughput in each interface, and issues one of three commands to each PDR:
[0000] (1) Decrease traffic by a fixed percentage (decreaseFactor);
(2) Continue to regulate traffic at reduced rate; or
(3) Cease regulation.
[0041] Each PDR 303 applies a virtual-buffer based policing (i.e. token-bucket based policing) and RED dropping (described below) to make the dropping pattern more random.
[0042] Since the regulation at capacity over licensed level will be carried out by the PDR (i.e. on the Iu-ps) only, it is not enough for the central entity 301 to know only the Iub throughput. For example, suppose the central entity 301 calculates that the Iub throughput is 10% too high and it tells the PDR to reduce its traffic by 10%. The PDR reduces the low priority Packet Switched (PS) and High Speed (HS) Radio Access Bearers (RAB)s by 10% of its total volume. However, the total traffic may include both PS and Circuit Switched (CS) traffic. It may therefore be the case that PS/HS RABs and PS Streaming are only 50% of the total traffic. In this case, only 5% reduction will take place for the example described. Therefore the central entity also needs to know the total Iu throughput (both Iu-cs and Iu-ps, since the regulation will apply to traffic passing through Iu-ps only) in order to set the correct relative decreasing goal for each PDR.
[0043] Once both the Iub and Iu throughput are known, the central entity 301 can then calculate the relative PS part in the total traffic and decides how much each PDR should decrease its traffic volume to meet the goal on Iub level. For example, at traffic above the licensed level, each PDR should decrease its volume by:
[0000]
max
(
1
,
Iub
-
allowedLevel
Iub
*
Iu
cs
+
Iu
ps
Iu
ps
)
[0000] where Iub, Iu cs and Iu ps are node level Iub, Iu-cs and Iu-ps throughput respectively.
[0044] Iub/Iu throughput may be measured by the DCS in a similar manner to that currently used to handle Performance Monitoring (PM) counters. The volume of Dedicated Channel (DCH) traffic can be measured in DcsIub before the various PM counters are stepped. The volume of High Speed Channel (HS) and Common Channel (CCH) traffic can be measured in DcsMacD. The combined traffic volume from each SP board is reported to module Measurement Points (MPs) in certain intervals. The setting of this interval is discussed later. After getting these reports, module MPs will in turn report the volume to central MP.
[0045] FIG. 4 illustrates the steps carried out by the central entity (throughput licence control) 301 . Once the measured throughput from the Iu and Iub interfaces is received 401 from the DCSs, the measured rate is compared 402 to the license rate modified by a factor (1−pHist). pHist is a parameter of the method, which may be set by the operator, or may be a constant. If the measured rate is below the threshold, the PDRs are checked 403 to see if they are currently dropping packets. If they are not currently dropping packets then the process finishes and waits 404 for one second, before receiving 401 the next set of measurements from the DCSs. If the PDRs are dropping packets, then a parameter of the method “nGood” is increased 405 and compared 406 to another parameter “pGood”. pGood may be set by the operator, or may be a constant, and sets the number of consecutive measurement intervals for which the measured rate is below the threshold before the PDRs stop dropping packets. If enough intervals have passed with the rate below the threshold (i.e. nGood>pGood), then the PDRs stop dropping packets 408 . If the measured rate has dropped below the threshold temporarily (e.g. only one measurement was below it) then nGood is not greater than pGood and the PDR continues to drop packets 408 .
[0046] If the measured rate is greater than the threshold, it is then compared 409 to a higher threshold determined by the license rate modified by the factor (1+pHist). If it is higher than this second threshold then the PDRs are instructed 410 to begin dropping packets, and the parameter nGood is set to zero. The measured rate must then drop below the lower threshold (licenseRate×(1−pHist)) for at least pGood measurement intervals for the PDRs to stop dropping packets.
[0047] If the measured rate is between the lower and higher thresholds (i.e. (licenseRate×(1−pHist))<measuredRate<(licenseRate×(1+pHist))), then the PDRs are checked 407 to see if they are dropping packets. If they are not, then they do not start to drop packets. The process finishes and waits 404 for one second, before receiving 401 the next set of measurements from the DCSs. If they are currently dropping packets then they continue to do so 412 , but nGood is set to zero so that the measured rate must still drop below the lower threshold (licenseRate×(1−pHist)) for at least pGood measurement intervals for the PDRs to stop dropping packets. The use of the parameter pHist provides a degree of hysteresis to the process to reduce oscillation of turning the PDR packet dropping on and off when the measured rate is at or near the licensed rate.
[0048] FIGS. 5 and 6 illustrate the operation carried out by the PDRs 303 following instructions from the central entity 301 . When the decreaseFactor is greater than zero, a target throughput (targetRate) is determined, based on the measured throughput (measuredRate) modified by the decreaseFactor. Packets are then dropped 501 to bring the throughput into line with the targetRate. When the decreaseFactor is zero, the PDR continues to operate 502 to drop packets based on the previous parameter settings (i.e. the targetRate is not modified). If the instructions are to “switch off” then no packets are dropped 503 .
[0049] Thus each PDR 303 has two states:
[0000] (1) Regulation is ON. In this state the virtual buffer based dropper is working.
(2) Regulation is OFF. The dropper is switched off, i.e. all packets are forwarded.
In this state there is no need to update the virtual buffer at all.
[0050] Each PDR 303 uses a virtual buffer 601 with capacity C and buffer length B. The virtual buffer occupancy is described by a parameter called “bufferOccupancy”. A moving average of bufferOccupancy is also determined, and described by parameter “MAbufferOccupancy”. MAbufferOccupancy is updated whenever the bufferOccupancy is changed, and the update proceeds as MAbufferOccupancy=0.9 MAbufferOccupancy+0.1 bufferOccupancy. The PDR 303 is configured with time parameters identified as “upper” and “lower” which (when combined with the targetRate) correspond to upper and lower limits on the MAbufferOccupancy. A suitable value for “lower” might be 0.3 seconds.
[0051] When the dropper is switched on (OFF→ON), the bufferOccupancy and MAbufferOccupancy are set to “targetRate×lower”, where targetRate is calculated from the latest measuredRate and decreaseFator (as described above).
[0052] The bufferOccupancy is increased by the packet size whenever a packet is forwarded. In other words, dropped packets do not increase bufferOccupancy.
[0053] The PDR 303 also uses a timer with a suitable period (e.g. 20 ms). The bufferOccupancy is periodically decreased by “targetRate×20 ms” and the maximum of 0 and bufferOccupancy is determined (i.e. the bufferOccupancy is prevented from dropping below zero). There is a higher probability of packets being dropped at the end of each 20 ms interval, but this is not a problem from the perspective of the end-user. There is a small probability that a user is synchronized to this 20 ms and does not have delay variance.
[0054] When a packet 602 arrives, if the MAbufferOccupancy is smaller than the lower limit in bits (lower×targetRate) then the packet is forwarded 603 . If the MAbufferOccupancy is larger than the upper limit then the packet is dropped 604 .
[0055] When the MAbufferOccupancy is between the lower and upper limits then the packet is dropped (provided it is larger than 200 bytes) with a probability determined by pr=(MAbufferOccupancy-lower limit)/(upper limit-lower limit). This is the RED method alluded to above.
[0056] In order to carry this out a random number, denoted by r, is generated between 0 and 1. Then
if r<=pr then drop packet if r>pr then forward packet.
[0059] Small control packets (i.e. IP packet size<200 byte) are only dropped when “MAbufferOccupancy>upper”.
[0060] When a new decreaseFactor is received from the central entity 201 , the targetRate changes as described above. The lower and upper limits in bits are then calculated from the new targetRate. The bufferOccupancy is unaffected by the change in targetRate.
[0061] There is no difference between the handling of TCP and User Datagram Protocol (UDP) packets. Packets are distinguished on the basis of their size only, and there is no need to look into the headers. As previously mentioned, packets smaller than 200 bytes are dropped only when the MAbufferOccupancy is larger than the upper limit. This has the advantage that small packets are normally not dropped, but in the extreme case that most packets are small the total throughput can still be kept below the licensed level.
[0062] A simulation can be performed to determine how the method operates with a licensed capacity that varies over time, and the results of such a simulation are discussed below. The licence capacity was varied as follows:
[0000]
Time
Licence capacity
(seconds)
(Mbps)
0-150
10
150-500
25
500-600
Infinity
600-700
10
700-800
20
800-900
30
900-1000
40
[0063] Three scenarios were simulated. In each case new users were started at intervals of 250/(maximum no. of users) seconds.
[0064] The performance of the three scenarios is compared in the following table:
[0000]
Small
Medium
Large
Downloaded traffic
2882.54
2934.86
2999.07
over TCP [Mbyte]
# IP packets
2312977
2325258
2513754
# Dropped IP packets
260684
252319
42095
# TCP Timeouts
55707
44812
2400
# Fast retransmission &
90836
94715
21150
fast recovery
[0065] It is clear that there is no significant difference among the amount of downloaded data through TCP sessions. This means that, at application level, the performance of the proposed policing method does not depend significantly on the traffic model used. For the traffic models based on small and medium objects there are many more timeouts than for the traffic model based on large objects. This is probably because the TCPs are more sensitive for packet loss in a slow start phase.
[0066] Thus it can be seen that the policing method described keeps the licence rate well. For smaller object sizes the number of timeouts increases, and the deviation in the object bitrates gets larger. However, the TCP throughput does not significantly decrease.
[0067] The methods described above have the advantage that many PDRs are handled at the same time. Furthermore, packet delay is not increased, and the method is TCP friendly.
[0068] In addition to this, the methods described enable the RNC seller to offer lower capacity and thus avoid price pressure per Mbps (“pay as you grow”). It is possible to ensure that operators will not (perhaps unknowingly) load the RNC beyond verified levels. It is also possible to verify higher levels than Iub-max and then sell extra capacity. If the RNC licensing capacity method is never activated then the operator traffic must always be below the licensed rate. However, if the method is constantly activated then it provides an indication that the operator requires additional capacity. | A method of controlling the rate of traffic flow through an Iub interface of a Radio Network Controller is described. The method includes obtaining a licensed rate, which defines the maximum throughput permitted through the Iub interface, at the Radio Network Controller. The rate of traffic flow through the Iub interface and all Iu interfaces of the Radio Network Controller is measured, and the extent to which packet switched traffic flow through the Iub interface exceeds the licensed rate identified. If the packet switched traffic flow through the Iub interface exceeds the licensed rate, packets are dropped from traffic flow through the Iub interface to reduce the traffic flow to the licensed rate. | 7 |
BACKGROUND OF THE INVENTION
[0001] This invention is a nanofabricated membrane including polymerized proteoliposomes. In one embodiment of the present invention, the membrane is a protein-incorporated water selective membrane.
[0002] In a conventional reverse osmosis membrane as provided in U.S. Pat. No. 6,878,278, there is a polyamide surface on a porous membrane employing Schotten-Baumann reaction with multifunctional amine monomer and polyfunctional acyl halide monomer. However, some chemicals such as trimesoyl chloride (TMC) destroy protein functionality because the chemicals have a highly hydrolysing property. That means it is difficult, if not impossible, to in situ incorporate a protein-incorporated polymerized liposomes into the polyamide matrix which is necessary for filling external spaces of the proteolipsomes.
BRIEF SUMMARY OF THE INVENTION
[0003] The present invention generally related to a nanofabricated membrane including polymerized proteoliposomes. The nanofabricated membrane is a bio-nano fused selective membrane using protein-incorporated uv-crosslinkable liposomes with a chemical reactive biocompatible interstitial matrix. In the present invention, internally UV-crosslinked protein-incorporated proteolipsomes are used because the proteoliposomes made by natural lipids have a short life time and a weak resistance to the circumstantial stresses such as a high and low temperature, pressure, ionic strength etc. Furthermore, the proteo-vesicles made by amphiphilic block copolymers provide less consistency in accomplishing proper functionality batch to batch because of the inevitable polydiversity of the polymer.
[0004] The synthesized and UV mediated polymerizable liposomes have UV-crosslinkable chemical structure in the hydrophobic area and higher consistency to make proteoliposomes than amphiphilic triblock copolymer. Additionally, the polymerized proteoliposomes have a strong mechanical resistance to the physical stress. Moreover, the chemical structure of the hydrophilic region of the lipid monomer may be modified to connect to an interstitial matrix or modify the surface of support or base membranes through various induced covalent bonds.
[0005] In one embodiment of the present invention, the present invention seeks to accomplish the following: 1) lipid incorporation into a conventional polyamide surface and 2) a biocompatible polyamide matrix for in situ proteoliposome incorporation using homobifuntional poly ethylene glycol (PEG) crosslinker or amine-dendrimers 3) lipid incorporation into a amine group modified cellulose nanomembrane, mixed cellulose ester nanomembrane, glass surface, and amine modified silicon or any possible materials that can be modified by amine groups.
[0006] In one embodiment of the present invention, the incorporated protein is a member of the Aquaporin family of proteins. However, it should be understood that the present invention is not limited to only this family of proteins. The resulting membrane has a water bypass through Aquaporin mediated water selective transportation and hollow space in the polymerized proteoliposomes in the biocompatibly reconstituted interstitial matrix. This membrane is capable of showing high water selectivity, water permeability, and low energy requirement owing to the Aquaporin functionality.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The features and advantages of the present invention will become apparent from the following detailed description of a preferred embodiment thereof, taken in conjunction with the accompanying drawings, in which:
[0008] FIG. 1 shows an enlarged view of the liposome wall wherein a UV-crosslinkable functional group is present in the hydrophobic part of the lipid monomer;
[0009] FIG. 2 shows a process for reconstructing the polymerized proteoliposome by UV exposure in accordance with one embodiment of the present invention;
[0010] FIG. 3 shows the chemical crosslinking between vesicles in accordance with one example embodiment of the present invention;
[0011] FIG. 4 shows an amine containing phospholipid (e.g. ethanolamine phospholipid) with a hydrophilic part (head group) for surface modification of a thin polyamide layer on the MCE (mixed cellulose ester) and Nylon base membrane in accordance with one embodiment of the present invention;
[0012] FIG. 5 shows the lipid incorporated base membrane to connect the polymerized proteolipsomes on the covalent bond matrix on top of the base membrane in accordance with one embodiment of the present invention;
[0013] FIG. 6 shows in situ embedding polymerized proteolipsomes with uv-crosslinkable amine-PEG hydrogel, biocompatible interstitial matrix wherein: (a) a base membrane is provided in the depth adjustable cast; (b) polymerized proteoliposomes and uv-crosslinkable PEG solutions were doped on the base membranes, if needed EDC mediated crosslinking between amine-PEG and phosphated lipids may be performed; (c) UV curing for membrane hardening; (d) detaching the fabricated membrane from the cast and (e) schematics of cross-section of the in situ embedded membrane in accordance with one embodiment of the present invention. The base membrane will be activated with amine groups or acrylic acids to induce the crosslinking with liposomes and hydrogel. Inkjet printing technology would be used to the in situ embedded membranes.
[0014] FIG. 7 shows a base membrane free desalination filter fabrication with (a) polymerized proteoliposomes coated threads for the weaving method and (b) water resistant fibrous structure between polymerized proteoliposomes with the non-woven method.
DETAILED DESCRIPTION OF THE INVENTION
[0015] In order to obtain a nanofabricated membrane in accordance with the present invention, polymerized proteoliposomes are first formed by incorporating proteins ( 6 ) into UV-crosslinkable liposomes ( 1 ). The UV-crosslinkable liposomes ( 1 ) are synthetic using material that mimic the structure of natural lipids. As shown in FIG. 1 , the UV-crosslinkable liposomes ( 1 ) (for example 1-palmitoyl-2-(10Z,12Z-tricosdiynoyl)-sn-glycero-3-phosphocholine, 1-palmitoyl-2-(10Z,12Z-tricosdiynoyl)-sn-glycero-3-phosphoethanolamine, 1,2-di-(10Z,12Z-tricosdiynoyl)-sn-glycero-3-phosphocholine, 1-2-(10Z,12Z-tricosdiynoyl)-sn-glycero-3-phosphoethanolamine) have UV-crosslinkable chemical structure ( 2 ) in the hydrophobic area ( 3 ); 10,12-pentacosadiynoic acid (PCDA) and its functional derivatives of hydrophilic part (fluorescent diacetylene monomers). It is understood that the UV-crosslinkable chemical structure may be included in one or both of the hydrophobic tails ( 5 ). The UV-crosslinkable liposome also comprises a hydrophilic area ( 4 ). In one embodiment, the UV-crosslinkable chemical structure ( 2 ) may include diacethylene for internal cross-linking. However, the present invention should not be limited to this specific UV-crosslinkable chemical structure ( 2 ) as those of ordinary skill in the art could select additional UV-crosslinkable chemical structures ( 2 ) without departing from the scope of the present invention. FIG. 1 shows one embodiment of the present invention having a schematic structure of 1-Palmitoyl-2-(10Z,12Z tricosadiynoyl)-sn-glycero-3-phosphoethanolamine (Diyne PE) as the hydrophobic area ( 3 ). This internal UV-crosslinking provides a liposome that has strong mechanical resistance to physical stress. After the UV-crosslinkable liposomes ( 1 ) are formed the protein ( 6 ) is incorporated into the wall of the liposomes using known techniques. In one embodiment of the present invention, Aquaporins are used as the proteins ( 6 ) to be incorporated. However, it is understood that other proteins ( 6 ) may be incorporated into the UV-crosslinkable liposomes ( 1 ) as known to those of skill in the art. Once the protein ( 6 ) is incorporated into the UV-crosslinkable liposome ( 1 ), the proteoliposome is polymerized using UV exposure to form the polymerized proteoliposome ( 7 ). FIG. 2 shows the proteoliposome ( 7 ) prior to UV crosslinking. After the proteoliposome is exposed to UV radiation, the polymerized proteoliposome ( 8 ) is formed by UV-crosslinkable functional groups ( 2 ) in the hydrophobic part ( 3 ) of the liposome ( 1 ).
[0016] As shown in FIG. 3 , the head group, or hydrophilic region, ( 4 ), of the polymerized proteoliposomes ( 8 ) are chemical modified to increase connectivity through external crosslinking between proteoliposomes or proteoliposomes and interstitial matrix. The hydrophilic area ( 4 ) of the synthesized lipids may include various multifunctional amines, carboxylates and phosphates. The head groups may be modified using hetero functional crosslinkers for example, N-Hydroxysuccinimide ester (NHS ester)—Biotin or imidoester-Biotin can be used for biotinlyation. The modification is performed by covalent crosslinking using various kinds of chemical conjugates ( 11 ) including, but not limited to, photoreactive crosslinkers, zero-length crosslinkers, homobifunctional crosslinkers, heterobifunctional crosslinkers, trifunctional crosslinkers, dendrimers and other known chemical conjugation methods. In the zero-length crosslink for amide linkage, carbodiimides may be used. In one embodiment of the present invention, EDC (1-ethyl-3-(3-dimethylamineopropyl)carbodiimide hydrochloride is used as the crosslinking agent. However, other carbodiimides may be used without departing from the scope of the present invention. The amine groups of the 2,2′ (Ethylenedioxy)bis(ethylamine) are useful for covalent crosslinking of carboxylate or phosphate groups of the proteoliposomes, through EDC activation. The polymerized proteoliposomes are highly resistant to solvents and other reaction. Therefore, the polymerized proteoliposome itself could be used for a good linker between polymerizable proteoliposomes and polyamide thin layer likewise in the structure between myosin and actin filaments. FIG. 4 shows amine phospholipid (e.g. ethanolamine phospholipid) containing hydrophilic parts ( 4 ) for surface modification of the thin polyamide layer on an MCE (mixed cellulose ester) and Nylon base membrane ( 12 ). To plant the liposomes ( 1 ) in the polyamide thin layer, amine-containing natural lipids and UV-crosslinkable lipids can be used. One or more amine sources are used to form a polyamide matrix that includes hydrophobic parts ( 3 ) that face up on the matrix. FIG. 5 shows the proteoliposomes ( 7 ) prior to UV exposure and the final UV-crosslinked polymerized proteoliposomes ( 8 ) including internal and external crosslinking ( 9 ) of the liposomes ( 1 ) and the liposome modified polyamide matrix ( 12 ).
[0017] To encapsulate the polymerized proteoliposomes ( 8 ) in the matrix, the proteoliposomes ( 7 ) are incorporated with the matrix on the base membrane ( 12 ) simultaneously. This process is referred to herein as “in situ incorporation”. FIG. 6 shows the fabrication process of hydrogel-proteoliposomes. The process includes the following steps: (a) a base membrane ( 13 ) is provided in the depth adjustable cast ( 14 ); (b) polymerized proteoliposomes ( 8 ) and uv-crosslinkable PEG solutions were doped ( 15 ) on the base membranes ( 13 ), if needed EDC mediated crosslinking between amine-PEG and phosphated lipids may be performed and polymerized proteoliposomes activated with NHS-acrylic acid can be used for connecting uv-crosslinkable PEG; (c) UV curing for membrane hardening; and (d) detaching the fabricated membrane from the cast. FIG. 6( e ) shows a schematic of the cross-section of the in situ embedded membrane in accordance with one embodiment of the present invention.
[0018] For further application of the polymerized proteoliposome technology, polymerized proteoliposome coated hydrolyzed nylon threads may be formed as shown in FIG. 7 . The hydrolyzed nylon thread ( 16 ) includes carboxyl and amine groups on its surface for covalent crosslinking with the polymerized proteoliposomes. FIG. 7 shows a desalination filter fabrication that is free from a base membrane with (a) polymerized proteoliposomes coated threads ( 16 ) for a weaving method ( 17 ) and (b) water resistant fibrous structure between polymerized proteoliposomes with a non-woven method for example by exposing them to UV-crosslinking light.
[0019] In another aspect of the invention, polymerized proteoliposomes including the Aquaporin family of proteins incorporated into the liposome wall may be formed into the membranes, including woven structures and non-woven structures, provided above that result in stable films that will only pass water, thus facilitating water purification, desalinization, and molecular concentration through dialysis. The aquaporins exclude the passage of all contaminants, including bacteria, viruses, minerals, proteins, DNA, salts, detergents, dissolved gases, and even protons from an aqueous solution, but aquaporin molecules are able to transport water because of their structure. Water moves through the membrane in a particular direction because of hydraulic or osmotic pressure. Water purification/desalinization can be achieved with a two-chambered device separated by a rigid membrane at its center that is filled with aquaporins. The membrane itself is impermeable to water and separates contaminated water from purified water in the chamber. Only pure water is able to flow between the two chambers. Thus, when sea water or other contaminated water on one side of the membrane is placed under an appropriate pressure, pure water naturally flows into the other chamber. Accordingly, purified water can be obtained from undrinkable sources or, if the source water contained chemicals of interest, the water can be selectively removed, leaving a high concentration of the wanted chemicals in the input chamber.
[0020] Importantly, however, the aquaporins are also suited to this invention for reasons other than their exclusive selectivity for water. Many members of this protein family (such as AquaporinZ (AqpZ) are extremely rugged and can withstand the harsh conditions of contaminated source water without losing function. AqpZ resists denaturing or unraveling from exposure to acids, voltages, detergents, and heat. Therefore, the device can be used to purify source water contaminated with materials that might foul or destroy another membrane, and it can be used in areas that experience consistently high temperatures. AqpZ is also mutable. Since this protein is specifically expressed in host bacteria according to a genetic sequence that influences its final shape and function, a technician can easily change its genetic code in order to change the protein's characteristics. Therefore the protein can be engineered to fulfill a desired application that may be different from the protein's original function. For example, by simply changing a particular amino acid residue near the center of the water channel to cysteine, the Aquaporins produced would bind any free Mercury in the solution and cease transporting water due to the blockage. Thus, these mutant proteins used in a membrane device could detect Mercury contamination in a water sample by simply ceasing flow when the concentration of the toxic substance rises too high.
[0021] Thus, there has been disclosed methods and apparatus utilizing biological components to achieve the highly efficient production of completely pure water from fouled, salty, or otherwise contaminated water. The invention demonstrates the integration of water transporting biological proteins with an external device, and points the way toward a manufacturing pathway capable of large-scale production of water purification devices.
[0022] The contents of U.S. Pat. No. 7,208,089, entitled “Biomimetic membranes”, is expressly incorporated herein by reference. The International patent application, PCT/US08/74163, entitled “Biomimetic Polymer Membrane that Prevents Ion Leakage”, is expressly incorporated herein by reference. The International Patent application, PCT/US08/74165, entitled “Making Functional Protein-Incorporated Polymersomes”, is expressly incorporated herein by reference. The U.S. Provisional application 61/055,207, entitled “Protein Self-Producing Artificial Cell, is expressly incorporated herein by reference.
Example
[0023] The following is an example of one embodiment of the present invention. It is understood that various modifications of this Example may be performed without departing from the scope of the invention.
[0024] 1. Polymerized Proteoliposomes
[0025] The UV reactive polymerizable lipids that have uv-crossliking chemical groups (for example, polyacetylene) in the hydrophobic area (for example, 16:0-23:2 Diyne PC—Avanti cat#790146 or 23:2 Diyne PC—Avaanti cat#870016 or 10-12-pentacosadiynoic acid, polydiacetylene etc.) were dissolved in the chloroform or t-butanol with the concentration of 5 mg/ml. The thin film can be made in 2 ways:
a. The dissolved lipid solution was transferred in the glass vacuum flask that was completely dried. To form the thin film inside the glassware, the solution was dried with gently shaking under the heavy gas (Argon or Nitrogen gas) jet. To remove the solvents completely, the dried thin film was purged over 4 hours or more. b. A solution of the dissolved lipid in t-butanol in a round bottom flask was attached to a rotary vapour and the solvent was removed under reduced pressure at ˜40° C. to 70° C. The film is dried for about 60 minutes or longer to effect complete drying. The film can be used immediately or stored under an inert atmosphere at −80° C.
[0028] Subsequently, the buffer-Aquaporin mixture (the required concentration of buffer (100 mM MOPS-Na, pH 7.5 or 20 mM PBS pH 7.5) detergent (octyl glucoside, triton X-100, dodecyl maltoside etc.) and protein) was added in the thin film formed glassware. Continuously, the mixture with thin film was sonicated under the heavy gas jet until the solution becomes transparent. After that the solution was dialyzed against the assay buffer (50 mM MOPS-Na, 150 mM N-Methyl-D-Glucamine, 1 mM Sodium Azide, pH 7.5 or 20 mM PBS buffer, pH 7.5) for 2 days changing fresh buffer at least 3 times. After dialysis, the dialyzed solution was diluted two times with assay buffer and filtered with 0.22 um of the disposable syringe filter. The functionality of Aquaporin incorporated proteoliposomes was measured before UV polymerization with stop flow light scattering (SFLS). Until this step, whole process should be accomplished in the dark room. To calculate the permeability of the proteoliposomes, dynamic light scattering (DLS) is necessary to measure the size of the liposomes.
[0000] To make polymerized proteoliposomes, the proteoliposomes were polymerized with 254 nm wavelength of UV exposure for 10 minutes.
[0029] 2. Modification of the Head Group of the Lipid Monomers to Increase Connectivity Through External Crosslinking Between Proteoliposomes or Proteoliposomes and Interstitial Matrix.
[0030] To construct the covalent chemical crosslinking, various kinds of chemical conjugations were used such as photoreactive crosslinkers, zero-length crosslinkers, homobifunctional crosslinkers, heterobifunctional crosslinkes, trifunctional crosslinkers, tetrafunctional crosslinkers, dendrimers and so on. In the photoreactive crosslinkers, there are acrylic acid derivates and acryl azide derivates such as NHS-acrylic acid and NHS-ASA (NHS-4-azidosalicylic acid), and bis-[(β-(4-azidosalicylamido)ethyl]disulfide (BASED). In the zero-length crosslinks for amide linkages, there are carbodiimides such as EDC (1-ethyl-3-(3-dimethylamineopropyl)carbodiimide hydrochloride, EDC with Sulfo-NHS(N-hydroxysulfosuccinimide), CMS (1-chclohexyl-3-(2-morpholinoethyl)carbodiimide), DCC (dicyclohexyl carbodiimide), DIC (diisopropyl carbodiimide), Woodward's reagent K (N-ethyl-3-phenylisoxazolium-3′-sulfonate), CDI (N,N′-carbonyldiimidazole). In conventional protein conjugation methods, EDC is a biocompatible mediator for making the peptide bond (amide bond). For this reaction, the amine group is necessary for the covalent crosslink (peptide bond) through EDC activated carboxylate groups or phosphate groups. In the homofunctional crosslinkers, there are homofunctional NHS esters; dithiobis(succinimidylpropinate) (DSP), 3,3′-dithiobis(sulfosuccinimidylpropionate) (DTSSP), disuccinimidyl suberate (DSS), bis(sulfosuccinimidyl)suberate (BS 3 ), disuccinimidyl tartarate (DST), disulfosuccinimidyl tartarate (sulfo-DST), bis[2-(succinimidyloxycarbonyloxy)ethyl]sulfone BSOCOES, bis[2-(sulfosuccinimidyloxycarbonyloxy)ethyl]sulfone (sulfo-BSOCOES), Ethylene glycolbis(succinimidylsuccinate) (EGS), Ethylene glycolbis(sulfosuccinimidylsuccinate) (sulfo-EGS), dicuccinimidyl gluarate (DSG), N,N′-disuccinimidyl carbonate (DSC), and bisNHS(PEG)n. And homofuncitonal imidoesters such as dimethyl adipimidate (DMA), dimethyl pimelimidate (DMP), dimethyl suberimidate (DMS), dimethyl 3,3-dithobispropionimidate (DTBP). In the heterofuncitonal crosslinkers, there are NHS-hydrazine moiet (SANH), NHS-adldyde moiet (SFB) etc. In the trifunctional crosslinkers, there are 4-azido-2-nitrophenylbiocytin-4-nitrophenyl ester (ABNP), sulfosuccinimidyl-2-[6-(biotinamido)-2-(p-azidobenzamido)hexanoamido]ethyl-1,39-dithopropinate (sulfo SBED).
[0031] In the tetrafuntional crosslinker, there are avidin, streptavidin, and neutravidin which can react with 4 biotins.
[0032] Various multifunctional amines, biotins, carboxylates, and phosphates can be added in the hydrophilic area of the synthesized lipids. Additionally, the photoreactive crosslinkers such as acrylic acids, diacethylene, methacrylate are used for inducing the membrane hardening through crosslinking between polymerized proteoliposomes or interstitial matrix.
[0033] 3. Lipid Incorporation into Polyamide Matrix
[0034] The polymerized proteoliposomes are highly resistant to dissolving solvent and other reaction. Therefore, it was determined that the UV-crosslinkable lipid (or liposome, in the following just examplified to as the liped) itself could be used for a good linker between polymerizable proteoliposomes and polyamide thin layer likewise in the structure between myosin and actin filaments. To plant the UV-crosslinkable lipid in the polyamide thin layer, we used ethanolamine included natural lipids and UV-crosslinkable lipid. The ethanolamine group was used as one more amine source to form the polyamide matrix expecting hydrophobic part to face up on the matrix. To do this process, MCE (mixed cellulose ester) and Nylon porous membranes (other membranes such as durapore and isopore membranes could also be used) were soaked in the lipid solvent solution. Subsequently, the solvent was evaporated and incubated in the diamine chemicals such as m-phenylenediamine or any other polyfunctional amine. After removing and drying excess amount of amine source, it was treated with a polyfunctional acylhalide such as trimesoyl chloride (TMC) (or any other acyl derivatives that can form an amide bond) that is dissolved in a non-polar organic solvent like hexane. The reaction is finished in several seconds and the excess amount of TMC was washed in the deionized water completely. A structure as shown in FIG. 4 was expected. Water droplet contact angle observations indicated that the hydrophobicity is increased as would be expected if the hydrophilic parts of the liposomes. After this reaction, we figured out increasing the hydrophobicity of the lipid included matrix is increased. This means hydrophilic area is facing up as expected.
[0035] 4. In Situ Incorporation into Biocompatible Matrix Such as Peg Included Hydrogel or Amine Dendrimers
[0036] For the in situ incorporation of the polymerized proteoliposomes in the interstitial matrix, some biocompatible materials are necessary. Poly ethylene glycol (PEG) and amine-dendrimers are good candidates for the purpose.
[0037] Poly ethylene glycol (PEG) has been used for conjugating biomolecules due to its water solubility and biocompatibility. PEG is a kind of polymer that shows low polydiversity and has capability to incorporate reactive groups such as UV-crosslinkable reagents, metal chelating agents, fluorescence, ligands, etc. In addition, carboxylate group can be attached in the PEG to be able to lead the EDC mediated biocompatible crosslinking reaction with amine groups. The PEG polymer is able to form a hydrogel through attaching the methacrylate UV-crosslinkable chemical. This PEG hydrogel approach was used in hardening lipid planar membrane in previous study. In this example, carboxylated or amine attached PEG hydrogel were used as a nanosized crosslinking spacer between the polymerized proteoliposomes.
[0038] In addition, the cellulose included support membranes can be activated by 3-amiopropyltriethoxysilane (APTES) which can provide primary amine functional group for in situ crosslinking with various kinds of amine mediated crosslinkers. Moreover, the UV-crosslinking groups can be used with that. The FIG. 6 shows the fabrication process of hydrogel-proteoliposomes. The polymerized proteoliposomes solution and UV-crosslinkable PEG hydrogel solution are water-based solutions. The solutions are mixed together and doped on the base membrane in the depth adjustable mould. After curing with UV, a highly compacted and hardened membrane is formed.
[0039] Dendrimers are usually used as multivalent bioconjugating scaffolds that are preconstructed by ethylenediamine (EDA) and emthylacrylate. The size of dendrimers can be regulated in the nanometer level by synthetic stage that is G-0 (1.4 nm, 3 amine surface groups)˜G-4 (4.4 nm, 48 amine surface groups). Those dendrimers have multifunctional amine attached structure and are able to be used as a biocompatible interstitial matrix through crosslinking phosphated or carboxylated groups in the hydrophilic area (head group) of the UV-crosslinkable liposomes through the EDC mediated amide bond formation.
[0040] In addition, another non-toxic process to the protein using poly-L-lysine that is a natural heterobifunctional amine with SMCC can be used to make amide bond with amine groups with EDC mediated reaction. The matrix from both materials is well known as the bio-compatible material that can make a soft cushion to immobilize the polymerized proteoliposomes.
[0041] 5. Fabrication for the Base Membrane Free Reverse Osmosis Membranes.
[0042] For the further application of the polymerized proteolipsome technology, polymerized proteoliposome coated hydrolysed nylon threads can be produced. The hydrolyzed nylon thread in high temperature (80° C.) includes carboxyl groups and amine groups on its surface. Likewise previous mentioned zero length conjugating methods; the polymerized proteoliposomes can be covalently crosslinked on the activated thread with EDC mediated amide bond formation as shown in FIG. 7( a ). Or cellulose treads that are activated by APTES and interacted with amine crosslinkers may be used.
[0043] In addition, it was reported that high density polyethylene may be formed using non-woven fibrous sample with CO 2 spraying ( Ind. Eng. Chem. Res., 1997, 36 (5), pp 1586-1597). The polymerized proteoliposomes of the present invention may be used with these high density polyethylene materials because the polymerized proteoliposomes has high resistance to the outside circumstance.
[0044] Although the present invention has been disclosed in terms of a preferred embodiment, it will be understood that numerous additional modifications and variations could be made thereto without departing from the scope of the invention. | The present invention generally related to a nanofabricated membrane including polymerized proteoliposomes. The nanofabricated membrane is a bio-nano fused selective membrane using protein-incorporated uv-crosslinkable liposomes with a chemical reactive biocompatible interstitial matrix. In the present invention, internally UV-crosslinked protein-incorporated proteolipsomes are used because the proteoliposomes made by natural lipids have a short life time and a weak resistance to the circumstantial stresses such as a high and low temperature, pressure, ionic strength etc. Furthermore, the proteo-vesicles made by amphiphilic block copolymers provide less consistency in accomplishing proper functionality batch to batch because of the inevitable polydiversity of the polymer. | 8 |
TECHNICAL FIELD
[0001] The invention relates to a new family of amine-tunable ruthenium catalysts based on chiral bisdihydrobenzooxaphosphole ligands (BIBOP ligands). The catalysts are useful for asymmetric hydrogenation and transfer hydrogenation of a variety of highly challenging ketones, including heteroaryl cyclic ketones.
BACKGROUND OF THE INVENTION
[0002] Asymmetric reduction of ketones is a key transformation in the pharmaceutical industry for the preparation of enantiomerically pure alcohols, particularly those bearing heterocycles (see, e.g., The handbook of Homogeneous Hydrogenation (Eds.: J. G. De Vries, C. J. Elsevier), Willey-VCH, Weinheim, 2007; and C. Hedberg, in Modern Reduction Methods (Eds.: P. G. Andersson, I. J. Munslow), WILEY-VCH, Weinheim, 2008, pp. 109-134). Chiral RuCl 2 (diphosphine)(diamine) complexes pioneered by Noyori and co-workers catalyze highly efficient asymmetric hydrogenation of a wide array of ketones to afford the corresponding alcohols (see, e.g., T. Ohkuma et al., J. Am. Chem. Soc. 1995, 117, 2675-2676; H. Doucet et al., Angew. Chem. Int. Ed. 1998, 37, 1703-1707; and T. Ohkuma et al., J. Am. Chem. Soc. 1998, 120, 13529-13530). Despite the variety of catalysts described in the literature (see, e.g., K. Mikami et al., Angew. Chem. Int. Ed. 1999, 38, 495-497; M. J. Burk et al., Org. Lett. 2000, 2, 4173-4176; and J. Wu et al., Chem. Eur. J. 2003, 9, 2963-2968); very few ruthenium catalysts have been able to hydrogenate cyclic ketones such as 1-tetralones (see, e.g., T. Ohkuma et al., Org. Lett. 2004, 6, 2681-2683; and T. Touge et al., J. Am. Chem. Soc. 2011, 133, 14960-14963). Furthermore, examples of heteroaryl cyclic ketones hydrogenation are extremely rare. To our knowledge, the only reported asymmetric hydrogenation of a heteroaryl cyclic ketone utilized a Ru-BINAP complex with a 1,4-diamine derived from natural mannitol for the reduction of 4,5,6,7-tetrahydrofuran-4-one (see T. Ohkuma et al, Org. Lett. 2004, 6, 2681-2683). In addition, only a few chiral catalysts have been reported to exhibit turnover numbers (TON, molar ratio of converted substrate to catalyst) over 100,000 with simple aryl methyl ketones, while most of the reported chiral catalysts have TON lower than 1000, making these catalytic systems unsuitable for industrial applications (see, e.g., K. Tsutsumi et al., Org. Proc. Res. Develop. 2009, 13, 625-628). In the synthesis of potential cholesterylester transfer protein (CETP) inhibitors, we needed to perform an asymmetric reduction of the advanced intermediate ketone of type 1 as such as depicted in Scheme 1.
[0000]
[0003] The reduction of 1 was initially conducted with one equivalent of borane-diethylaniline and 15-20 mol % (1R,2S)-cis-1-amino-2-indanol to afford 84% yield of (S)-2 in 96:4 er on multi-kilogram scale. Though the reaction performed well on scale-up, a greener and more efficient catalytic method was desired.
[0004] Therefore, there is a need for a more efficient method for carrying out asymmetric hydrogenations such as that shown in Scheme 1.
BRIEF SUMMARY OF THE INVENTION
[0005] The invention relates to a process of using ruthenium compounds for carrying out asymmetric reduction of ketones (“the process of the invention”). The invention also relates to novel ruthenium compounds (“the compound of the invention”) which are useful for carrying out the process of the inventions.
COMPOUNDS OF THE INVENTION
[0006] In one embodiment (“embodiment 1”), the invention relates to ruthenium compounds of formulae (Ia) and (Ib):
[0000]
[0000] wherein R 1 are both the same and selected from —H, —CH 3 and —OCH 3 ; and
the moiety
represents a diamine ligand selected from the group consisting of compounds 4, 5, 6, 7, 8, 9, and 12:
[0000]
[0007] In another embodiment (“embodiment 2”), the invention relates to the compound of formula (Ia) or (Ib) according to embodiment 1, wherein R 1 is —H.
[0008] In another embodiment (“embodiment 3”), the invention relates to the compound of formula (Ia) or (Ib) according to embodiment 1, wherein R 1 is —CH 3 .
[0009] In another embodiment (“embodiment 4”), the invention relates to the compound of formula (Ia) or (Ib) according to embodiment 1, wherein R 1 is —OCH 3 .
[0010] In another embodiment (“embodiment 5”), the invention relates to the compound of formula (Ia) or (Ib) according to embodiment 1, wherein the diamine ligand is compound 4.
[0011] In another embodiment (“embodiment 6”), the invention relates to the compound of formula (Ia) or (Ib) according to embodiment 1, wherein the diamine ligand is compound 5.
[0012] In another embodiment (“embodiment 7”), the invention relates to the compound of formula (Ia) or (Ib) according to embodiment 1, wherein the diamine ligand is compound 6.
[0013] In another embodiment (“embodiment 8”), the invention relates to the compound of formula (Ia) or (Ib) according to embodiment 1, wherein the diamine ligand is compound 7.
[0014] In another embodiment (“embodiment 9”), the invention relates to the compound of formula (Ia) or (Ib) according to embodiment 1, wherein the diamine ligand is compound 9.
[0015] In another embodiment (“embodiment 10”), the invention relates to the compound of formula (Ia) or (Ib) according to embodiment 1, wherein the diamine ligand is compound 12.
[0016] In another embodiment (“embodiment 11”), the invention relates to the compound of formula (Ia) or (Ib) according to any one of embodiments 5 to 10, wherein R 1 is —OCH 3 .
[0017] In another embodiment (“embodiment 12”), the invention relates to the compound of formula (Ia) or (Ib) according to embodiment 1, wherein the diamine ligand is compound 8.
[0018] In another embodiment (“embodiment 13”), the invention relates to the compound of formula (Ia) or (Ib) according to embodiment 12, wherein R 1 is —H.
[0019] In another embodiment (“embodiment 14”), the invention relates to the compound of formula (Ia) or (Ib) according to embodiment 12, wherein R 1 is —CH 3 .
[0020] In another embodiment (“embodiment 15”), the invention relates to the compound of formula (Ia) or (Ib) according to embodiment 12, wherein R 1 is —OCH 3 .
[0021] In another embodiment (“embodiment 16”), the invention relates to the compound of formula (Ia) according to any one of embodiments 1 to 15.
[0022] In another embodiment (“embodiment 17”), the invention relates to the compound of formula (Ib) according to any one of embodiments 1 to 15.
[0023] In another embodiment (“embodiment 18”), the invention relates to compound 13:
[0000]
[0024] In another embodiment (“embodiment 19”), the invention relates to compound 27:
[0000]
[0025] In another embodiment (“embodiment 20”), the invention relates to compound 28:
[0000]
PROCESSES OF THE INVENTION
[0026] As noted above, the inventors have found that the novel ruthenium compounds of the invention are useful as catalysts for carrying out asymmetric hydrogenation of ketones to provide chiral alcohols (“process of the invention”). Typically, at least about 90% of the ketone is converted to alcohol; more preferably at least about 95% of the ketone is converted to alcohol; most preferably, at least about 99% of the ketone is converted to alcohol.
[0027] The process of the invention also provides an excess of one enantiomer of the alcohol (e.g., the S-enantiomer) relative to the other enantiomer, (e.g., the R-enantiomer). Preferably, the enantiomeric ratio (er) of the isomers of the alcohol formed by the process of the invention is at least about 75:25; more preferably, the er is at least about 85:15; even more preferably, the er is at least about 90:10; still even more preferably, the er is at least about 95:5; most preferably, the er is at least about 99:1.
[0028] In one embodiment (“embodiment 21”), the invention relates to a process for making a chiral alcohol of formula X1, the process comprising reacting a ketone of formula Y1 with hydrogen in the presence of a ruthenium compound, wherein
[0000] the ketone of formula Y1 and the corresponding chiral of formula X1 are as defined below:
[0000]
Ketone (Y1)
Alcohol (X1)
the ruthenium compound is
(a) the compound of formula (Ia) as defined in embodiment 1, wherein R 1 is —OCH 3 , and the diamine ligand is compound 12; or
(b) the compound of formula (Ib) as defined in embodiment 1, wherein R 1 is —OCH 3 , and the diamine ligand is compound 4, 5, 6 and 7.
[0032] In another embodiment (“embodiment 22”), the invention relates to a process for making a chiral alcohol of formula X2, the process comprising reacting a ketone of formula Y2 with hydrogen in the presence of a ruthenium compound, wherein
the ketone of formula Y2 and the corresponding chiral of formula X2 are as defined below:
[0000]
Ketone (Y2)
Alcohol (X2)
the ruthenium compound is
(a) the compound of formula (Ia) as defined in embodiment 1, wherein R 1 is —CH 3 , and the diamine ligand is compound 5;
(b) the compound of formula (Ia) as defined in embodiment 1, wherein R 1 is —OCH 3 , and the diamine ligand is compound 8, 9 or 12; or
(c) the compound of formula (Ib) as defined in embodiment 1, wherein R 1 is —H or —CH 3 , and the diamine ligand is compound 8.
[0038] In another embodiment (“embodiment 23”), the invention relates to a process for making a chiral alcohol of formula X3, the process comprising reacting a ketone of formula Y3 with hydrogen in the presence of a ruthenium compound, wherein
the ketone of formula Y3 and the corresponding chiral of formula X3 are as defined below:
[0000]
Ketone (Y3)
Alcohol (X3)
the ruthenium compound is
(a) the compound of formula (Ib) as defined in embodiment 1, wherein R 1 is —OCH 3 , and the diamine ligand is compound 12; or
(b) the compound of formula (Ia) as defined in embodiment 1, wherein R 1 is —OCH 3 , and the diamine ligand is compound 4, 5, 6 and 7.
[0043] In another embodiment (“embodiment 24”), the invention relates to a process for making a chiral alcohol of formula X4, the process comprising reacting a ketone of formula Y4 with hydrogen in the presence of a ruthenium compound, wherein
the ketone of formula Y4 and the corresponding chiral of formula X4 are as defined below:
[0000] Ketone (Y4) Alcohol (X4)
and
the ruthenium compound is (a) the compound of formula (Ib) as defined in embodiment 1, wherein R 1 is —CH 3 , and the diamine ligand is compound 5; (b) the compound of formula (Ib) as defined in embodiment 1, wherein R 1 is —OCH 3 , and the diamine ligand is compound 8, 9 or 12; or (c) the compound of formula (Ia) as defined in embodiment 1, wherein R 1 is —H or —CH 3 , and the diamine ligand is compound 8.
[0049] In another embodiment (“embodiment 25”), the invention relates to the process of the invention as described in any one of the embodiments 21 to 24, wherein the ketone is contacted with the ruthenium compound prior to reaction with hydrogen.
[0050] In another embodiment (“embodiment 26”), the invention relates to the process of the invention as described in embodiment 25, wherein the ketone is contacted with the ruthenium compound and a solution of potassium tert-butoxide in tert-butanol prior to reaction with hydrogen.
[0051] In another embodiment (“embodiment 27”), the invention relates to the process of the invention as described in embodiment 26, wherein the ketone is contacted with the ruthenium compound, a solution of potassium tert-butoxide, and isopropanol prior to reaction with hydrogen.
[0052] In another embodiment (“embodiment 28”), the invention relates to the process of the invention as described in embodiment 27, wherein the ketone of formula is contacted with the ruthenium compound, and potassium tert-butoxide prior to reaction with hydrogen.
[0053] It will be understood that in the process of the invention described in any one of the embodiments 21 to 28, the ruthenium compounds can be used in isolated form or prepared in situ by reacting the corresponding precatalysts of formula (Va) or (Vb):
[0000]
[0000] with the appropriate ligand of formula 4, 5, 6, 7, 8, 9 or 12 as defined in embodiment 1; wherein R 1 is as defined in embodiment 1. As used herein, the term “isolated” as it relates to a Ru compound and its use in the process of the invention means that the Ru compound is substantially separated from unreacted compound of formula (Va) or (Vb) and diamine ligand prior to use.
[0054] Thus, in one embodiment (“embodiment 29”), the invention relates to the process of carrying out the asymmetric hydrogenation of ketones as described in any one of embodiments 21 to 28, wherein the compound of formula (Ia) or (Ib) is prepared in situ from the reaction of the compound of formula (Va) or (Vb), respectively, with the diamine ligand of formula 4; or the compound of formula (Ia) or (Ib) is prepared in situ from the reaction of the compound of formula (Va) or (Vb), respectively, with the diamine ligand of formula 5; or the compound of formula (Ia) or (Ib) is prepared in situ from the reaction of the compound of formula (Va) or (Vb), respectively, with the diamine ligand of formula 6; or the compound of formula (Ia) or (Ib) is prepared in situ from the reaction of the compound of formula (Va) or (Vb), respectively, with the diamine ligand of formula 7; or the compound of formula (Ia) or (Ib) is prepared in situ from the reaction of the compound of formula (Va) or (Vb), respectively, with the diamine ligand of formula 8; or the compound of formula (Ia) or (Ib) is prepared in situ from the reaction of the compound of formula (Va) or (Vb), respectively, with the diamine ligand of formula 9; or the compound of formula (Ia) or (Ib) is prepared in situ from the reaction of the compound of formula (Va) or (Vb), respectively, with the diamine ligand of formula 12.
[0055] In another embodiment (“embodiment 30”), the invention relates to a process for making the ruthenium compounds of the invention, the method comprising:
[0000] reacting a compound of formula (Va) with the diamine ligand of formula 4 to provide a compound of the invention;
reacting a compound of formula (Vb) with the diamine ligand of formula 4 to provide a compound of the invention;
reacting a compound of formula (Va) with the diamine ligand of formula 5 to provide a compound of the invention;
reacting a compound of formula (Vb) with the diamine ligand of formula 5 to provide a compound of the invention;
reacting a compound of formula (Va) with the diamine ligand of formula 6 to provide a compound of the invention;
reacting a compound of formula (Vb) with the diamine ligand of formula 6 to provide a compound of the invention;
reacting a compound of formula (Va) with the diamine ligand of formula 7 to provide a compound of the invention;
reacting a compound of formula (Vb) with the diamine ligand of formula 7 to provide a compound of the invention;
reacting a compound of formula (Va) with the diamine ligand of formula 8 to provide a compound of the invention;
reacting a compound of formula (Vb) with the diamine ligand of formula 8 to provide a compound of the invention;
reacting a compound of formula (Va) with the diamine ligand of formula 9 to provide a compound of the invention;
reacting a compound of formula (Vb) with the diamine ligand of formula 9 to provide a compound of the invention;
reacting a compound of formula (Va) with the diamine ligand of formula 12 to provide a compound of the invention; or
reacting a compound of formula (Vb) with the diamine ligand of formula 12 to provide a compound of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Abbreviations
[0056] AcOH=acetic acid
ampy=2-aminomethylpyridine
amqui=8-aminoquinoline,
BINAP=(R)-(+)-(1,1′-Binaphthalene-2,2′-diyl)bis(diphenylphosphine),
i-Pr-BIMAH=2-(α-(i-propyl)methanamine)-1H-benzimidazole,
Xyl-BINAP=2,2′-bis(bis(3,5-dimethylphenyl)phosphino)-1,1′-binaphthalene,
DCM=dichloromethane,
daipen=1,1-Bis(4-methoxyphenyl)-3-methyl-1,2-butanediamine,
dpen=1,2-diphenylethane-1,2-diamine,
IPA=isopropyl alcohol,
RUCY™-XylBINAP=Chloro {(R)-(+)-2,2′-bis[di(3,5-xylyl)phosphino]-1,1′-binaphthyl}[1-(4-methoxyphenyl)-1-(4-methoxyphenyl-kC)-3-methyl-1,2-butanediamine]ruthenium(II),
paraphos=13-[(triphenylmethoxy)methyl]tricyclo[8.2.2.2 4,7 ]hexadeca-4,6,10,12,13,15-hexaene-5,11-diyl]bis[diphenylphosphine],
Xyl-Phanephos=4,12-Bis(di(3,5-xylyl)phosphino)-[2.2]-paracyclophane,
P-phos=2,2′,6,6′-Tetramethoxy-4,4′-bis(diphenylphosphino)-3,3′-bipyridine,
Xyl-Skewphos=2,4-bis(di-3,5-xylylphosphino)pentane,
tBu=t-butyl group,
Tot=tolyl group,
Xyl=xylyl group,
Me=methyl group
[0057] The term “er” is the enantiomeric ratio and is the ratio of the percentage of one enantiomer of the alcohol (e.g., the S-enantiomer) to the other enantiomer (i.e., the R-enantiomer).
[0058] Hydrogenation of ketone 1 was evaluated using 32 commercially available RuCl 2 (diphosphine)(diamine) complexes (S/C 50) with t-BuOK in IPA (see Table 1 for representative conditions). This initial screen identified RuCl 2 [(S)-tol-BINAP][(S)-i-Pr-BIMAH] as a suitable catalyst for the reduction of 1 providing (R)-2 in quantitative yield and 98:2 er. Additional screening of solvents revealed RuCl 2 [(S)-tol-BINAP](ampy) (ampy=2-aminomethylpyridine) in ethanol as another active catalytic system, affording (R)-2 in quantitative yield and 98:2 er. However, upon catalyst loading optimization studies, complete conversion was not achieved at S/C<1000, which was not economically feasible for scale-up due to the high cost of the catalysts.
[0000]
TABLE 1
Evaluation of commercial Ru-complexes
for the asymmetric hydrogenation of 1.
Entry
Ru-complex
Conversion(%) a
er b
1
RuCl 2 [(R)-BINAP][(R)-daipen]
11
—
2
RuCl 2 [(R)-Xyl-BINAP][(R)-daipen]
23
5:95
3
RuCl 2 [(R)-BINAP][(R,R)-dpen]
6
—
4
RuCl 2 [(S)-Tol-BINAP][(S)-i-Pr-
100
98:2
BIMAH]
5
RuBr 2 [(S)-Xyl-Skewphos](ampy)
96
8:92
6
RuCl 2 [(R)-Xyl-Phanephos][(S,S)-dpen]
0
—
7
RuCl 2 [(S)-Xyl-P-Phos][(R)-daipen]
1
—
8
RuCl 2 [(S)-Paraphos][(R,R)-dpen]
100
79:21
9
RuCl 2 [(S,S)-DIOP][(S)-i-Pr-BIMAH]
98
26:74
10
(R)-RUCY ™-Xyl-BINAP
10
17:83
11
RuCl 2 [(S)-Tol-BINAP](ampy)
100
98:2
a molar conversion as determined by HPLC;
b recorded as R:S;
c EtOH as solvent Enantiomeric ratios were determined by chiral HPLC;
The R absolute configuration of 2 was determined by chemical correlation to the final product.
[0059] At this point, the reaction was evaluated using BIBOP ligands, which we had previously developed for rhodium-catalyzed hydrogenation of functionalized olefins (see W. Tang et al., Org. Lett. 2010, 12, 176). RuCl 2 (BIBOP)(p-cymene) complexes 3 were prepared from BIBOP and [RuCl 2 (p-cymene)] 2 in EtOH/CH 2 Cl 2 . To evaluate the efficiency of the new catalytic system, the hydrogenation of 1 was explored in-situ with several diamines (Table 2).
[0000]
TABLE 2
Evaluation of Ru-BIBOP/diamine complexes in the reduction of 1.
Conditions:
H 2 (400 psi), 4-5 mol % precatalyst 3, 4-5 mol % diamine, t-BuOK, IPA, 25 ° C., 15 h, molar conversion as determined by HPLC;
er recorded as R:S
[0060] As shown in Table 2, the highest enantioselectivities (over 99:1 er) were observed with ampy, 8,2-aminomethylpyrimidine, 9, and amqui, 12. Interestingly, inverse enantioselectivity was observed when changing the R substituent in the BIBOP ligand from hydrogen (3a) or methyl (3b) to methoxy (3c) with 8 as diamine, going from 9:91 and 6:94 to >99:1 er, respectively. Inverse selectivity effects were also observed with a given phosphine complex 3 and different amines, i.e. 3c provided opposite enantioselectivities with diamines 4 and 5 than 8-12.
[0061] To evaluate the reactivity of the most selective catalysts for the reduction of 1, we synthesized the corresponding RuCl 2 (BIBOP)(diamine) complexes by reaction of 3 with the corresponding diamines in toluene at 110° C. Isomeric mixtures of at least four isomers were observed by 31 P-NMR spectroscopy when using diamines 8, 9 and 12. As reported for other 2-aminomethylpyridine complexes, no differences in reactivity or enantioselectivity were observed regardless of the isomeric ratio of the pre-catalyst mixture. Screening of the pre-made RuCl 2 (MeO-BIBOP)(diamine) catalysts along with optimization of the reaction conditions for solvent, pressure and temperature, allowed the synthesis of (R)-2 using RuCl 2 (MeO-BIBOP)(ampy) at S/C 20,000 under 300 psi of hydrogen on 0.5 kg scale in 98% yield and >99:1 er.
[0062] The prepared catalysts were also efficient for asymmetric transfer hydrogenation applications. When 1 was treated with 0.2 mol % 13 and 10 mol % sodium isopropoxide in IPA at 80° C., a 93% yield of (R)-2 and >99:1 er was obtained. Table 3 shows the results of the asymmetric hydrogenation of an exemplary heteroaryl cyclic ketone (ketone 14) of the invention to provide alcohol 15.
[0000]
TABLE 3
Asymmetric hydrogenation of ketone 14.
Entry
Ru-complex
Conversion (%) a
er b
1
RuCl 2 [(R)-BINAP][(R)-daipen]
98
86:14
2
RuCl 2 [(R)-Xyl-BINAP][(R)-daipen]
100
68:32
3
RuCl 2 [(S)-BINAP][(S,S)-dpen]
100
12:88
4
RuCl 2 [(S)-BINAP][(S)-i-Pr-BIMAH]
100
60:40
5
RuBr 2 [(S)-Xyl-Skewphos[](R)-daipen]
100
87:13
6
RuCl 2 [(R)-Xyl-Phanephos][(S,S)-dpen]
100
56:44
7
RuCl 2 [(S)-Xyl-P-Phos][(R)-daipen]
100
92:8
8
RuCl 2 [(S)-Paraphos][(R,R)-dpen]
100
49:51
9
RuCl 2 [(S,S)-DIOP][(S)-i-Pr-BIMAH]
100
49:51
10
(R)-RUCY ™-Xyl-BINAP
96
35:65
11
3c + 4
100
1:99
12
3c + 5
100
10:90
13
3c + 6
100
5:95
14
3c + 7
100
3:97
15
3c + 8
100
59:41
16
3c + 12
100
90:10
a molar conversion as determined by HPLC;
b recorded as R:S
[0063] The new Ru-BIBOP catalysts also proved to be more selective than 34 commercially available complexes in the reduction of 4,5,6,7,8-tetrahydro-5-quinolinone, 14 (see Table 3 for representative examples). Evaluation of commercial complexes allowed up to 92:8 er by using RuCl 2 [(S)-Xyl-P-Phos][(R)-daipen] (entry 7). The highest enantioselectivities of >97:3 er were obtained when using complex 3c with (R,R)-dpen, 4, or (S)-daipen, 7 (entries 11 and 14). A remarkable inversion of the stereoselectivity was observed when using 3c in combination with 12 (entry 16) instead of diamines 4-7 (entries 11-14). Although some scattered examples of inversion of stereoselectivity can be found in the literature, no general evaluation has been undertaken. [8]
[0064] The reduction of other heterocycles to provide isoquinolines 16-17, benzothiophene 18, benzofuranone 19, and pyrazole 20 also resulted in high selectivities (Table 4).
[0000]
TABLE 4
Asymmetric hydrogenation scope of cyclic ketones of formula (Y1)
or alkyl ketones of formula (Y2) using RuCl 2 (MeO-BIBOP)(diamine).
Reaction conditions:
0.1-2 mol % RuCl2[(2R,2′R,3S,3′S)-MeO-BIBOP](diamine), 0.2 equiv of t-BuOK, IPA, 25° C., 20 h under 400 psi of hydrogen;
The enantiomeric ratios were determined by chiral HPLC and refer to S/R ratios;
Absolute configurations were assigned by comparison of optical rotation with reported data or with authentic samples.
[0065] Complete inversion of enantioselectivity was observed in when using pre-made complexes 26 and 27. These catalysts also provided high stereoselectivities of 1-tetralols 21-22. Aryl alkyl ketones such as acetophenone, p-bromoacetophenone and 3-acetylpyridine were also suitable substrates providing 23-25 in enantiomeric ratios of 94:6, 95:5 and 95:5, respectively, when using the dpen complex 26. Interestingly, in the case of the aryl methyl ketones, no inversion of enantioselectivity was observed when using the amqui complex 27.
Examples
[0066] General procedure for hydrogenation: Hydrogenation of 28 illustrates the typical reaction procedure: To a mixture of 1-tetralone, 28, (10.0 g, 66.4 mmol) and RuCl 2 [(2R,2′R,3S,3'S)-MeO-BIBOP](amqui), 27, (1.0 mg, 0.001 mmol, 0.002 mol %) was added isopropanol (40 mL) and a 1 M solution of t-BuOK in tert-butanol (1.33 mL, 1.33 mmol, 0.02 equiv). The autoclave reactor was first purged with nitrogen, then with hydrogen, and then the reaction mixture was stirred at 60° C. under 400 psi of hydrogen for 20 h. After venting the hydrogen gas, the solvent was removed under reduced pressure. The residue was purified by silica-gel column chromatography with ethyl acetate/hexane (0-50%) as eluent to give (R)-1,2,3,4-tetrahydro-1-naphthol, 29, (colorless oil, 9.6 g, 98% yield, 96:4 er). The er of 1,2,3,4-tetrahydro-1-naphthol was determined by HPLC analysis: column, Chiralcel OJ-3, 4.6×150 mm; eluent, heptane/isopropanol (95:5); flow rate, 1 mL/min; column temperature, 25° C.; retention time (tR) of (R)-1,2,3,4-tetrahydro-1-naphthol, 7.45 min (95.8%); tR of (S)-1,2,3,4-tetrahydro-1-naphthol, 5.75 min (4.2%). [α]D=−31.2 (c=2.0, MeOH).
[0067] Except for cyclic ketone 1 (describe below), the cyclic ketones of formula (Y1) and alkyl ketones of formula (Y2) are commercially available or can be prepared known methods.
[0068] Preparation of cyclic ketone 1: Ketone 1 is prepared according to the method depiction in the Scheme 3 below.
[0000]
[0069] A dried 2 L jacket reactor is flushed with argon and then charged with 3,6-dihydro-2H-pyran-4-carbaldehyde (360.3 g, 57.4 wt %, 1.844 mol) and 5,5-dimethyl-cyclohexane-1,3-dione (336.1 g, >99 wt %, 2.398 mol). Isopropyl acetate (iPrAc, 1.05 L) is charged and the mixture is agitated for 10 min at about 20° C. The mixture is charged with 2,6-lutidine (42.96 mL, 0.369 mol) and then is agitated at reflux (about 90° C.) for 5.5 h with a water separator or Dean-Stark apparatus attached. The reaction is monitored by HPLC analysis. After completion of the reaction, the mixture is cooled to 20° C. and iPrAc (600 mL) is charged followed by aqueous hydrochloric acid (655 mL, 1 mol/L), and the mixture is agitated for 15 min. The aqueous layer is removed and the organic phase is washed with aqueous sodium hydroxide (655 mL, 2 M) and water (655 mL). The organic phase is concentrated to about 650 mL under vacuum and cooled to about 6° C. Heptane (2 L) is charged in over 1 h and the mixture stirred for 14 h at about 6° C. The slurry is filtered and the wet cake is washed with heptane (600 mL) and dried to yield Int-1 as a yellow solid (315.33 g, 96.6 wt %) in 70.5% yield.
[0070] A 2 L jacketed reactor is charged ammonium acetate (668 g, 8.67 mol) and the reactor is flushed with argon. Then 4-methyl-3-oxopentanoate (500 g, 3.47 mols) is charged followed by methanol (1.0 L). The mixture is agitated at 55° C. for 5 h and concentrated in vacuo to about 1 L and then cooled to about 20° C. A solution of iPrAc (1.5 L) is added and the organic phase is washed with water (2×1.0 L). The organic phase is concentrated to provide methyl 3-amino-4-methylpent-2-enoate (Int-2) as yellow oil (560 g, 68 wt %) in 76% yield, which is used directly in next step.
[0071] A dried 2 L jacket reactor is charged with Int-2 (193.5 g, 97.0 wt %, 0.801 mol) and Int-2 (208.9 g, 71.4 wt %, 1.04 mol), and the reactor is flushed with argon. The reaction is charged with acetic acid (AcOH, 950 mL) and the mixture is agitated at 105 to 110° C. for 7 h. The reaction is monitored by HPLC analysis. The mixture is cooled to about 20° C. and agitated for 1 h (significant amount of solids may crystallize out). Water (1.68 L) is charged to the mixture over 1.5 h to form a slurry and stirred for about 3 h. The slurry is filtered and the wet cake is washed with heptane (600 mL) and dried under vacuum at 75° C. for 3 days to yield Int-3 as a yellow solid (170 g, 98.6 wt %) in 58% yield.
[0072] A dried 2 L jacketed reactor is charged with Int-3 (130 g, 93.4 wt %, 0.338 mol) and methylene chloride (DCM) (800 mL), and the mixture is stirred and cooled to about 5° C. 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ, 79.0 g, 0.348 mol) is charged as a slurry in DCM (600 mL) while keeping the temperature at 5 to 10° C. The vessel is rinsed with DCM (2×100 mL) and charged to the reaction mixture. The reaction mixture is stirred for 30 min at 5 to 10° C. and then warmed to about 18 to 22° C. and agitated for 30 min. The reaction is monitored by HPLC analysis. The reaction mixture is concentrated under vacuum to ˜⅓ volume (˜600 mL) and chased with iPrAc (1.5 L) at about 50° C. to 80° C. The mixture is cooled to about 20° C. and charged with iPrAc (1.2 L), and the organic phase is washed with 1 M aqueous NaOH (1.5 L) and water (2×1.0 L). The organic solvents are concentrated under vacuum to about 1 L and the solution then passed through a silica plug. The silica plug is rinsed with iPrAc (500 mL) and the combined filtrates are concentrated to provide 1 as a solid (122 g, 93.2 wt %) in 93% yield. | Disclosed are novel ruthenium compounds of formula (Ia) and (Ib):
wherein R 1 and the moiety | 2 |
This application is a continuation of copending application Ser. No. 825,478, filed on Aug. 17, 1977.
BACKGROUND OF THE INVENTION
The present invention relates to a charger using one or more solar batteries and useful for small-size apparatus such as an electronic wristwatch.
It is well known that a nickel-cadmium (Ni-Cd) battery can be used as a power source for electronic wristwatches in combination with one or more solar batteries (SB). However, the Ni-Cd battery is not preferable because cubic efficiency of battery capacity is poor and the amount of self discharging is large. For instance, when the Ni-Cd battery has a diameter of 11.6 mm and a height of 5.1 mm, the battery capacity is about 20 mAH and the self discharging amounts to nearly 30% for 90 days. In contrast, a sealed type silver oxide battery, which consists of a positive electrode made of Ag, AgO or Ag 2 O and a negative electrode made of Zn or Cd, has excellent properties with respect to cubic efficiency, the self discharging, etc. For instance, in the case of a silver oxide battery of substantially the same size as the above, that is, a diameter of 11.56 mm and a height of 5.33 mm, the battery capacity is about 190 mAH and the amount of self discharging is about 10% per year when the electrolyte is NaOH and about 20% per year when the same is KOH. Moreover, the silver oxide battery shows charging efficiency up to about 90% while the Ni-Cd battery has a charging efficiency of only about 70%. Nonetheless, in the event that the silver oxide battery maintains its charge after full charging, the battery will swell out and the output voltage of the battery will swing. The former is deemed to occur due to the fact that gas is generated within the battery by the over-charging. The latter is deemed to occur because Ag oxide is dissolved into an alkali electrolyte and then shifted into the Zn negative electrode or Zn is deposited in a dendrite or spongy fashion to cause short circuiting.
Even in the prior art Ni-Cd battery, the battery might swell out by gas accumulation within the battery when more than 0.1 CA charging current flows under the full charged condition. To this end, a current limiting resistor or the like is usually connected to suppress the charging current in the order of less than 0.1 CA. However, unlike the Ni-Cd battery, the above-mentioned silver oxide battery will result in expansion of the battery or swinging of the output voltage even when the charging current is limited. A sealed type mercury battery consisting of a positive electrode made of Hg, HgO or Hg 2 O and a negative electrode made of Zn or Cd, must undergo the same circumstances.
Therefore, it is an object of the present invention to provide a charger which overcomes the above-mentioned disadvantages. According to the present invention, a charging current limiting means and a charging voltage limiting means are provided simultaneously in a charger unit including one or more solar batteries and a secondary battery such as a silver oxide battery. In one preferred form, the charging current limiting means and the charging voltage limiting means are enabled only when the solar batteries deliver the output voltage.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and novel features of the present invention are set forth in the appended claims and the present invention as to its organization and its mode of operation will best be understood from a consideration of the following detailed description of the preferred embodiment taken in connection with the accompanying drawings, wherein:
FIG. 1 is a characteristic chart showing relationship between permissible battery voltage and charging current of a silver oxide battery;
FIG. 2 is a circuit diagram showing one preferred form of the present invention;
FIG. 3 is a characteristic chart showing relationship between charging voltage and charging current;
FIG. 4 is a characteristic chart showing a charging property of the silver oxide battery;
FIG. 5 is a circuit diagram showing another embodiment of the present invention;
FIG. 6 is a circuit diagram showing still another embodiment of the present invention;
FIG. 7 is a circuit diagram showing another embodiment of the present invention; and
FIG. 8 is a characteristic curve showing relationship between charging voltage and charging circuit.
DETAILED DESCRIPTION OF THE INVENTION
Although the present invention is equally applicable to the silver oxide battery, the mercury battery or the like, details of the present invention will be set forth by way of example of the silver oxide battery.
FIG. 1 illustrates a battery voltage vs. charging current characteristic of the sealed type silver oxide battery with the numbers on the abscissa indicating the battery voltage E(V) and the numbers on the ordinate indicating the charging current I o (m A ). The battery will be operable well without any expansion or circuit-shorting provided that neither the battery voltage nor the charging current extends beyond a range surrounded by the slant lines. It is obvious from FIG. 1 that the battery voltage E keeps increasing with the development of charging and, if the charging current exceeds such permissible range, then the battery will swell out and short-circuiting will occur. In other words, it is not possible to overcome the swelling out and the short-circuiting of the battery even if the charging current is limited as was typical with the prior art Ni-Cd battery, because of further increasing of the battery voltage E. To solve this problem, it is required that the charging current be suppressed with respect to the battery voltage and therefore not only the charging current but also the battery voltage will be suppressed within the permissible range. Since the battery voltage never increases above the charging voltage, a limitation on the charging voltage means equally a limitation on the battery voltage.
FIG. 2 is a circuit diagram of a charging unit of a solar battery powered electronic wristwatch, wherein the charging current and the charging voltage are both properly limited. Reference 1 represents solar batteries, reference 2 represents a current limiting resistor, reference 3 represents a reverse current preventing diode, reference 4 represents the silver oxide batteries set forth above, and 5 represents a timekeeping circuit. In front of the current limiting resistor 2 and the reverse current preventing diode 3 a voltage switching circuit 6 is provided in parallel with the solar batteries 1. The circuit further comprises a voltage detecting transistor Tr 1 , switching characteristic improving transistors Tr 2 and Tr 3 , a constant voltage element Z such as a Zener diode available for shifting the operating point of the transistor Tr 1 upward and improving a temperature characteristic of the voltage switching circuit 6, a variable resistor R available for adjusting a bias voltage for the transistor Tr 1 , and temperature compensating diodes D 1 -D 3 available for accommodating temperature-depending variations in the permissible range of the battery voltage vs. charging current characteristic.
A voltage (Vo) vs. current (Io) characteristic of the charging unit of FIG. 2 is illustrated in FIG. 3. The silver oxide battery will be charged in proportion to the intensity of incident light onto the solar batteries; the curve (a) showing a process of charging under 15,000 lux, the curve (b) under 30,000 lux and the curve (c) under 50,000 lux. However, it is understood that the charging process is restricted as shown by the curve (d) upon arrival of the full charged condition. The curve (d) is determined mainly by the current limiting resistor 2, the reverse current preventing diode 3, and the voltage switching circuit 6. The leading voltage Vo 1 on the curve (d) is equal to a voltage turning on the voltage switching circuit 6 and the transistors Tr 1 , Tr 2 and Tr 3 minus the forward voltage of the reverse current preventing diode 3 and the incline of the curve (d) is determined by the resistance value of the current limiting resistor 2. FIG. 3 is plotted with 12 serially connected solar batteries each having a working area of 40 mm 2 . If a pair of the silver oxide batteries having substantially the same capacity is serially connected, the battery voltage vs. charging current characteristic assumes the same battery voltage as indicated within the parentheses of FIG. 1. Therefore, the voltage-current characteristic of FIG. 3 is settled within the slant line marked range shown by FIG. 1 to prevent swelling and short-circuiting of the batteries.
FIG. 4 illustrates a charging characteristic of the silver oxide battery at room temperature with the charging current of 3 mA indicating that charging can be accomplished with the charging voltage of 1.65 V. In the case where the two silver oxide batteries are serially connected, the charging current will flow sufficiently with 1.65×2=3.30 (V) as is clear from FIG. 3 so that the utilization of the circuit of FIG. 2 will not disturb the charging process. If there is any difference in the material which constitutes the silver oxide battery or in the characteristics of the serially connected plurality of silver oxide batteries, the battery voltage charging current characteristic will vary. In this instance, the variable resistor R is adjusted to change the on voltage of the voltage switching circuit 6. Alternatively, the resistance value of the current limiting resistor 2 may be varied.
FIGS. 5 and 6 show other embodiments wherein the voltage switching circuit 6 consists of a Zener diode ZD in case of FIG. 5 and consists of a series circuit of two GaP light emitting diodes D'0 and a Si diode D. The former utilizes the avalanche effect of the Zener diode ZD while the latter utilizes the forward voltage addition effects of the diodes. Although the Zener diodes manifest variations in the characteristics and particularly poor trailing properties, they can be overcome by combinations with Si diodes or light emitting diodes of GaP, GaAlAs, GaAs, etc.
Meanwhile, since the voltage switching circuit 6 is connected in front of the reverse current preventing diode 3, current never flows from the silver oxide batteries through the voltage switching circuit. In other words, the voltage switching circuit 6 operates only when incident light is applied to the solar batteries 1.
In case where the two silver oxide batteries are serially connected as stated above, the charging voltage is nearly 3.30 V for example. Assume now that current consumption by the voltage switching circuit 6 mainly the variable resistor R and the diodes D 1 -D 3 is 10 μA. When the solar batteries 1 are exposed to incident light for one (1) hour per day, the current consumption amounts to 10 μA hour/day. However, considering a case where the voltage switching circuit 6 is connected directly to the silver oxide batteries 4, the current consumption will be calculated as 24 hours×10 μA=240 μA hour/day. This shortens the operating life of the batteries more particularly for use in extremely small current operating appliances such as electronic wristwatches. In the event the voltage switching circuit 6 is connected directly to the silver oxide batteries 4 in FIGS. 5 and 6, current flows at all times due to the leading edge and trailing edge characteristics.
Contrarily, according to the above given examples, the circuit operates only when the solar batteries enjoy incident light, and thus enables a 1/24 reduction of the current consumption.
FIG. 7 shows a modification in the voltage switching circuit 6 which is connected in parallel with a series circuit of the solar batteries 1 and the current limiting resistor 2. When using a Schottkey barrier diode as the reverse-current preventing diode 3, the forward voltage may be reduced in comparison with the conventional PN junction diodes. In other words, the utilization of the Schottkey barrier diode permits the charging process to complete with a relatively small photovoltage of the solar battery 1. The voltage switching circuit defined by the dotted line is implemented with semiconductor integrated circuit technology together with the reverse-current preventing diode 3.
The voltage switching circuit 6 includes a voltage detecting transistor Tr 1 ', modified Darlington connected transistors Tr 2 ' and Tr 3 ' available for improving characteristics and Darlington connected switching transistors Tr 4 ' and Tr 5 ' and bias resistor R 1 and R 2 provided for the transistor Tr 1 ', which is biased adjustably with the resistor R 2 . A transistor Tr 6 ' connected between the resistors R 1 and R 2 operates as a diode to improve the temperature characteristic of the voltage switching circuit in union with a base-to-emitter diode characteristic of the transistor Tr 1 '.
The relationship between the voltage Vo and the current Io of the charging assembly of FIG. 2 is plotted in FIG. 8. The charging process is advanced as shown by the curve (a) under 9.6×10 4 lux, the curve (b) under 6.4×10 4 lux and the curve (c) under 3.2×10 4 lux. However, it should be understood that the charging process is restricted under the fully-charged condition as shown by the curve (d). The curve (d)is determined by respective characteristics of the reverse-current diode 3 and the voltage switching circuit 6. In other words, the leading voltage Vo 1 on the curve (d) is equal to the switching voltage of the voltage switching circuit 6 minus the forward voltage of the reverse-current preventing diode 3. The characteristics shown in FIG. 8 are obtained with eight (8) serially connected solar batteries each having working surface area of 12 mm 2 .
In case where the voltage-current characteristic (switching characteristic) of the switching circuit 6 is dull, or in case where an amount of incident light is varied within a wide range as compared with the voltage-current characteristics of the switching circuit, all the charging current Io will not be able to bias in other switching circuit 6 with the same voltage. This results in that the voltage Vo-current Io characteristics will vary for each of amounts of incident light as shown by the dotted lines (a)', (b)' in FIG. 8. When this occurs, the permissible range of the battery voltage-charging current is no longer expected at high intensity for example more than 9.6×10 4 lux.
The switching circuit 6 of FIG. 7 is adapted to exhibit a sharp switching characteristic. When the charging voltage Vo is increased, the voltage detecting transistor Tr 1 ' and the characteristic improving transistors Tr 2 ' and Tr 3 ' are turned on. Within the last stage switching transistors Tr 4 ' and Tr 5 ', the Darlington connection increases the current gain and decreases the on resistor of the transistor Tr 5 '. This makes the switching characteristic sharp together with operation of the characteristic improving transistors Tr 2 ' and Tr 3 '. Therefore, with such an arrangement, the characteristic is not varied upon variations in the amount of incident light so that the charging process is developed in accordance with the solid line characteristic without departing from the permissible range of the battery voltage-charging current shown in FIG. 1.
While only certain embodiments of the present invention have been described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention as claimed. | A charger, which is useful to power a variety of compact type electronic appliances such as an electronic wristwatch, includes one or more solar batteries as a primary battery, and a sealed type silver oxide battery as a secondary battery. Both the amount of charging current amplitude and of charging voltage are limited to protect the sealed silver oxide battery from its own expanse phenomenon. | 8 |
RELATED CASES
This application claims priority to my provisional patent applications, Application Ser. No. 60/134,100, filed May 14, 1999, and application Ser. No. 60/160,771, filed Oct. 21, 1999, for the same invention.
BACKGROUND-FIELD OF INVENTION
The present invention relates to an improved hole opener for use in increasing the diameter of holes in drilling and more specifically, to a hole opener having a set of arms that may be changed to increase the size of the cutter allowed to be used so that a variety of different sized holes might be drilled using the same hole opener body.
In the drilling industry, whether for exploration of oil and gas, mining, water well development or the like, an operator may desire to widen the existing diameter of a hole previously drilled. A number of prior art devices have been used for enlarging such holes. Most hole openers currently in use provide a fixed-arm arrangement which supports a pin through the cutter shell and are prone to failure when excessive wear allows the arm to fail and the pin to collapse, with the possibility that such devices might then be stuck in the hole, necessitating an expensive retrieval job.
SUMMARY OF THE INVENTION
The present invention provides a tubular body with threaded connections at either or both ends to enable connection in a drill string, and further providing a passage therethrough for the passage of drilling fluid, including air. The tubular body supports a plurality of detachable support arms for each cutter which are bolted, pinned, or otherwise removably attached to the tubular body and which engage the outer or distal end of a journal body. The journal body is engaged at its proximal end on a spindle providing an eccentric or otherwise non-circular profile so that the journal cannot be rotated on the spindle. Alternatively, the spindles may also be recessed in the tubular body providing additional structural support for the journals, and further providing a restraint to movement of the journal on the spindle. The journal provides bearings to facilitate rotation of a cutter on the journal. The cutter shell is carried on the journal body and eliminates the customary pin arrangement through the axis of rotation of the cutter body, which was used to support all known prior art hole openers. A pressure compensated means of lubricating the bearings on the journal is also provided thereby increasing the life of the bearings and the useful life of the hole opener.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side cut-away view of a form of the invention showing a smaller cutter shell and arm.
FIG. 2 is another cut-away view of a form of the invention showing the tubular body with a larger cutter shell and arm.
FIG. 3 is an enlarged cross-sectional view of the cutter support arm, journal and cutter shell supported on the tubular body.
FIG. 4 is an end view of the small cutter shells on the tubular body.
FIG. 5 is an end view of the larger cutter shells on the same tubular body shown in FIG. 4 .
FIG. 6 is cross-sectional side view of an alternative embodiment for use in larger diameter holes.
FIG. 7 is an end view of the large diameter hole opener of FIG. 6 .
FIG. 8 is a sectional view of a second form of embodiment of the invention with a pinned cutter arm.
FIG. 9 is a sectional view of the second form of embodiment with a larger cutter arm and larger cutter cone.
FIG. 10 is an enlarged cross-sectional view of the cutter support arm of FIG. 8 .
FIG. 11 is a sectional view of the cutter body through the section line of FIG. 8 .
FIG. 12 is a partial sectional view of the large diameter opener showing the attachment of the cutter arm secured to the body by the pins.
FIG. 13 is a partial sectional view of the large diameter opener showing an alternative attachment of the cutter arm secured to the body by cap head screws and secured by smaller diameter cap head screws.
FIG. 14 is a partial sectional view of another embodiment of the large diameter opener having a recessed seat for the journal body for strength and rigidity and further providing a lubrication reservoir and system for lubricating the bearings during operation.
FIG. 14 a is a cross-sectional view of the recessed groove area formed on the body of the hole opener.
DESCRIPTION OF THE INVENTION
The present invention is for a hole opener providing the means to use the tool for opening more than one diameter with the same tubular body by changing the support arm, the journal supported by that arm and the cutter shell.
In FIG. 1, the hole opener 10 provides a threaded pin 12 and a threaded box 14 at the other end to connect the tubular body 11 to a drill string or the like (not shown). The tubular body 11 provides a passage 16 through its longitudinal extent to allow the passage of drilling fluid, which can be liquid or air used to carry the cuttings from the well bore (not shown). The tubular body 11 is integrally formed with a larger diameter portion 19 . A stair-stepped groove or rabbet 21 extending from adjacent the larger diameter portion 19 to adjacent the eccentric spindle 20 formed on the body 11 to accept support arm 30 . Support arm 30 is secured to the tubular body by a plurality of socket head cap screws 43 , 43 ′ and 43 ″ of varying lengths that attach the support arm body 30 to the body 11 . Each of the socket head cap screws is further secured in the support arm body 30 by retainer ring 45 which is inserted in a groove 45 ′ formed on the interior surface of the support arm. The support arm body 30 provides a spindle 31 , which fits into the space formed by a journal 28 at its distal end. Journal 28 is formed with an eccentric or non-circular profile 22 on its proximal end to mate with spindle 20 on the tubular body 11 to prevent rotation of the journal 28 in either direction, allowing the hole opener to be used in either direction. Journal 28 provides bearings 27 and bearing races 29 to facilitate rotational movement of cutter shell body 25 on the journal 28 . Each of the cutter shells supported on the multiple support arms may be provided with hard facing in a manner well known to those skilled in the art, or may be provided with tungsten carbide buttons (not shown) also in a well known commercial manner. In the preferred embodiment, three support arm-cutter assemblies are provided on the hole opener 10 , but any number greater than three may be provided depending on the size of the hole desired.
Adjacent the cutter shell spindle 20 , the diameter of the body 11 is only increased to an amount equivalent to the smallest hole which the operator may wish to open and provides hard facing (not shown) or tungsten carbide buttons 18 to minimize wear on the tubular body 11 as it moves through the formation to be widened.
Tubular body 11 is additionally formed to provide passageway 50 which permits communication of the drilling fluid from the longitudinal passageway 16 to adjacent the cutter bodies through nozzle holder 52 and nozzle 53 in a manner well known in the drilling industry. The jetting nozzle 53 is recessed in the body of the largest diameter portion of the tubular body 11 spaced between each of the support arms.
FIG. 2 describes the hole opener with the same sized body as shown in FIG. 1, with the larger support arm 60 , journal 70 and cutter body 80 for widening the diameter of a larger hole with the same tubular body 11 . The tubular body 11 may be fitted with alternative sets of support arms 60 , larger journals 70 , and larger cutter shells 80 for a variety of wider hole sizes desired. The socket head cap screws 65 , 66 , and 67 are longer to support the larger support arm 60 on the body, but otherwise function in the same manner and are installed on the body in the same manner as the bolts for the smaller diameter hole opener of FIG. 1 . The function and operation of the hole opener would be equivalent to the hole opener described in connection with FIG. 1 .
FIG. 3 is an enlarged partial view of the hole opener of FIG. 2 showing the stair-stepped groove 21 formed in the large diameter portion body of the tubular body 11 , with the socket head cap screws 65 , 66 , and 67 , and retainer rings 45 seated in retainer ring grooves 45 ′. Cutter shell journal 70 provides additional roller bearings to support the additional cutting surface of the cutter shell 80 and facilitate rotational movement of the cutter shell on the journal. FIG. 3 more clearly shows the hard facing, which may be placed on the exterior surface 81 of the dihedral shaped cutter shell body. The face of cutter shell 80 may again be provided with either hard facing with grooves commonly referred to as a mill tooth cutter in the manner well known in the art or may provide tungsten carbide buttons (not shown).
Socket head cap screws 65 , 66 , and 67 , shown in FIG. 3 are one side view of two adjacent rows of bolts (for a total of six bolts) securing the support arm 60 to the tubular body 11 in the stair-stepped groove 21 , 21 ′, fashioned in the largest diameter portion 19 of the body 11 . Other arrangements of bolts and grooves may be made to the tool body without departing from the spirit of the invention made.
FIG. 3 further more clearly demonstrates the angle of the eccentric support spindle 20 from a normal (perpendicular) to the longitudinal axis of the tool. In prior art hole opener devices, the angle between the cutter axis and a plane perpendicular to the longitudinal axis of the tool supporting was approximately 30°; however, in the present device the angle of the spindle 20 to a perpendicular normal to the body 11 is approximately 20° or less. This lower angle requires less material be removed from the body to allow free rotation of the cutter. This additional material strengthens the overall body leading to longer service life and fewer failures in the field.
FIG. 4 is a partial schematic description of the end view of the hole opener with the smaller cutter shell bodies of FIG. 1 . This view clearly shows the dihedral shape of the cutter faces and the profile of the cutter in the hole. The profile of the hole opener 10 from the end demonstrates that the flow of drilling and fluids is not restricted with bracing or support for cutters permitting the free flow of drilling fluid and cuttings from the cutting face back along the periphery of the hole opener body 11 in the well bore annulus.
FIG. 5 is a similar schematic view of the end of FIG. 2 showing the larger cutter shells on the same hole opener body as FIG. 1 for opening a larger hole. Both FIG. 4 and FIG. 5 are shown without the tungsten carbide buttons shown in FIGS. 1, 2 , and 3 . As the cutter shells are enlarged the flow area around the cutter body is increased because the support arm only increase relative to the size of the cutter attached and does not encroach upon the fluid passage for the larger hole sizes.
FIG. 6 is a side view of a hole opener for use in large diameter holes, which functions in the same manner as the smaller diameter hole openers shown in FIGS. 1, 2 and 3 . A spindle block support gusset 119 is permanently attached to tubular body 111 and spindle block 117 is affixed to said gusset. Threaded pins 112 and threaded boxes 114 are again provided to permit connection of the hole opener 100 in the drill string. The spindle support block provides the attachment support for socket head cap screws 65 , 66 , and 67 to attach the support arm body 60 identical to that used in either FIGS. 1 or 2 . The cutter shell may be changed in a similar manner to go from a smaller diameter hole with hole opener 100 to a larger diameter hole by easily changing the support arm, journal and cutter shell as described herein.
Adjacent each spindle block support gusset, a pilot guide gusset 118 supporting a fluid spout 150 , jetting nozzle holder 152 and jetting nozzle 153 may be permanently attached to the body of the hole opener permitting fluid communication from the longitudinal passage formed through the body 111 of the hole opener to provide means for carrying the cuttings from the cutters up the periphery of the body 111 through the annulus of the well bore (not shown). The pilot guide gusset may be hard faced to prevent wear in a manner well known to the drilling trades such as shown in 121 .
FIG. 7 shows an end view of the large diameter hole opener 100 with threaded box 114 at the center and disclosing the preferred arrangement of the three spindle support block gussets 119 , 119 ′ and 119 ″ on which is affixed the spindle support block 117 into to which is attached the spindle support arms which provide engagement with the journals and cutters on said journals. Adjacent each of the three cutter support spindle blocks are the three fluid communication ports 150 with nozzle holder 152 and nozzle 153 supported on their respective pilot guide gussets 118 , 118 ′ and 118 ″. Each of the support gussets may be connected by support gussets 120 to provide additional lateral support for the gussets.
FIG. 8 is a view of the preferred embodiment of the hole opener with the support arms removably connected to the larger diameter portion 19 of body 11 by pins 68 , 68 ′, and 68 ″. As may be more clearly seen from cross-sectional view shown in FIG. 11, pin 68 is inserted in the enlarged portion 19 of body 11 through passage intersecting the stair-stepped groove 21 . Pin 68 is formed by any material of sufficient strength to secure arm 30 ′ in said groove 21 in a manner well known to those skilled in the art of manufacture of drilling equipment. A cap head bolt 69 is inserted in a slot 69 ″ formed in said body 19 to secure said pin in said body. A passage 69 ′ is provided on the opposite side of body 19 of lesser diameter than the passage provided for the pin 68 to permit the knock-out removal of the pin by an operator to remove or change the cutter arm 30 ′. As may be readily appreciated from FIG. 8, three pins are disclosed to hold the cutter arm in the stair stepped groove. Greater or lesser number of pins may be formed in the enlarged portion 19 of the tool body 11 to accommodate differing service requirements and drilling or hole enlarging environments.
In FIGS. 8 and 9, respectively, cutter arm 30 ′ and 60 ′ support cutter journals 28 and 70 and cutter bodies 25 and 80 in the same manner and operate in the same manner as the hole opener disclosed in FIGS. 1 and 2. The pins 68 , 68 ′ and 68 ″ which are used to secure the cutter arms on the body in FIG. 8 are an alternative and preferred methods of attachment to the cap head bolts of FIG. 1 and 2.
FIG. 10 is an expanded view of spindle support arm 60 ′ mounted on the expanded portion 19 of body 11 (as in FIGS. 1 and 2) with a larger cutter 80 and journal body 70 to permit a larger diameter hole to be enlarged utilizing the same tubular body 11 .
It may be appreciated that the cutter support arm of each FIGS. 1, 2 , 3 , 7 , 8 , 9 and 12 , may be attached in a number of ways to the tubular body (or to the spindle support block of FIG. 7 and 12) without departing from the disclosure and intent of the present invention. For example, the pins 68 , 68 ′ and 68 ″ could have alternatively been bolts or cap head screws with locking bolts or cap head screws. Additionally, the proximal end of the cutter support spindle might be affixed in a recess provided in the body 11 and either pinned or bolted by one or more screws onto the surface of the expanded body surface 19 .
In FIG. 13, an alternative embodiment of the cutter support arm connection is disclosed. Body 19 is tapped to provide threads at 150 for seating cap head screws 168 . A cap head screw 168 is inserted in the body 19 and through the hole machined into the proximal end of the cutter support arm 30 ′ and into the threaded body portion 150 . The cap head screw 168 seating in the threads 150 provides additional support for the cutter arm assembly and lessens the chance of fatigue failure from movement of the arm in the body. A smaller cap head screw 69 is seated adjacent the head of the cutter arm support cap head screw 168 to prevent loosening of the cap head screw 168 during operation.
FIG. 14 shows an alternative embodiment of the opener in which the body 19 is provided with a recess 23 into which is fitted the proximal end of the cutter body journal 70 . The profile shown in FIG. 14 provides rigidity and support for the journal 70 and allows the load placed on the cutter to be more evenly distributed to the body 19 . A cross-sectional view in FIG. 14 a shows the spatial relationship of the spindle 20 , the non-concentric recess 23 , and the upraised surface 17 against which the proximal end of the journal 20 is seated and supported off of the surface of groove 21 . The recess prohibits the movement of the journal which is urged into movement by the movement of the cutter shell around the center post or spindle 20 of the profile thereby reducing the wear on the journal surfaces which mate with the enlarged portion 19 of the opener body 11 and increasing the life of the journal 70 . In this alternative embodiment, the journal body provides a longitudinal pathway through and is fitted with a grease plug 71 and grease nipple 72 in a manner well known to those in the industry, which provides a grease reservoir to provide lubrication during operation. The proximal end of the journal body 70 is fitted with a slotted retainer sleeve 73 , which prevents the bearing plug 24 in the body of the journal 70 , while at the same time allowing communication of grease from the reservoir to the bearing race.
After the cutter body 80 and journal 70 are assembled and mounted on the spindle 20 and secured by cutter arm 60 , grease is injected through the nipple 72 and into the reservoir between the floating grease plug 71 and the top of the spindle 20 . The distal end of the cutter support arm 60 is machined to provide a path for a standard grease gun, in a manner well known to those in the industry. The floating grease plug 71 is assembled with a seal 73 which fits in a groove provided on the surface of the plug 71 , providing sealing engagement of the floating grease plug 71 with the interior surface of the journal body 70 . Grease is retained within the reservoir and bearing surfaces by seal 73 ′ seated in a groove on the inner periphery of journal body 70 , which seals against the exterior surface of spindle 20 . Seals are also provided for grooves machined on the exterior surface of the journal body 70 to prevent ingress of drilling fluid into the bearing surfaces in a manner well known to those in this industry.
Grooves are provided in the journal and bearing race to allow lubrication to occur during operation. The floating grease plug 71 balances the pressure acting on the grease reservoir and the bearing surfaces. As hydrostatic pressure builds against the seal surfaces around the bearings a proportionate pressure moves the floating grease plug 71 down the reservoir to balance the pressure on the interior of the reservoir and bearing surfaces. As the volume of lubricant changes during operation of the cutter, the equalizing pressure also forces the lubricant from the reservoir and around the bearings thereby extending bearing life.
These lubrication features may be used on hole openers with either cap headed screw as described in FIGS. 1, 2 , 3 , 6 , or with pins or screw supports as described in FIGS. 8, 9 , 10 , and 12 .
The present invention permits multiple hole sizes to be worked with one body. The support arm arrangement provides a safe, expedient means for changing the size of the hole sought to be enlarged without significant loss of time. The pin, which supported the spindle of the cutter found in many prior art devices, has been eliminated and the journal, which carries the cutter shell, is supported on both ends minimizing the bending moment associated with prior hole opener devices. The interchangeability of cutter support arms provides an efficient economic means for using a single tool for a variety of hole sizes. | A hole opener ( 10 ) having a tubular body ( 11 ) with threaded ends ( 12, 14 ) for connection in a drill string. The hole opener provides slots or grooves ( 21, 21 ′) along its longitudinal axis ( 16 ) into which are inserted cutter arm support members ( 30, 30′, 60, 60 ′) which may be screwed, ( 43 ) pinned ( 68 ) or bolted ( 168 ) to the body ( 11 ) to permit easy replacement of the support arms ( 30 ). The grooves ( 21, 21 ′) in the body ( 11 ) of the hole opener ( 10 ) also provide a spindle ( 20 ) spatially aligned with the groove ( 21, 21 ′) to support the proximal end of a rotatable journal body ( 28 ) supporting the cutter body ( 25 ) providing hard facing for grinding of the bore hole to be enlarged. The support arms ( 30 ) at their distal end provide further support for the cutter journals ( 70 ). The hole opener ( 10 ) also may provide pressure compensated lubrication mechanism ( 71 ) to provide grease to the bearing surfaces to increase their service life and thereby extend the useful life of the tool. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority from Provisional Application Ser. No. 60/357,807 filed Oct. 26, 2001.
BACKGROUND OF INVENTION
The invention relates to the field of printing using modern, high-feature printers. More specifically, the invention relates to facilitated and flexible processing of complex print job parameters such as document cover and sheet insert specifications.
At the outset, it is useful to review certain terminology which will be used in the following discussions. A print job typically is a data file stored accessibly to an information handling system such as a high function personal computer or a network server. The data file may have been originated in a number of ways known to printing technologists, including original document keying, scanning, use of graphics design programs, and the like. The print job may be understood as defining a sequence of pages. A page is one surface of a sheet. The sheet may be a cut sheet, as in a single piece of what is known to most as letter size paper, or a continuous roll. With two surfaces, a sheet may receive two pages. In transferring a print job to a printer, an operator will create a job ticket which describes to the printer or print server the control functions necessary to cause the print job to appear on the finished pages as desired by the originator. These control functions may include incorporation of special features or elements, repetition from one page to another of certain features or elements, changes in fonts or paper, and the like.
When preparing jobs for printing on high-feature printers, such as the IBM Infoprint 2000 and others, the job originator may specify job ticket instructions or parameters that are best perceived visually. These parameters may specify such elements as front and back covers and preprinted sheets that the system will add to the print job pages at prescribed locations in a sequence of pages.
Existing products and programs require that a job originator specify these parameters using traditional dialogs and by listing preprinted sheet locations by referring to original document pages; for example, “insert preprinted sheet A after page 3”. In such an environment, it is easy for the job originator to make a mistake because there is no visual feedback identifying exactly where each preprinted sheet or cover is to be placed. Some existing products use a proprietary application to provide a ‘tree view’ of the document that shows preprinted sheets as attached to the surrounding original pages.
It is desirable to provide a more intuitive way of accepting user specifications for cover sheets and preprinted inserts and illustrating the same visually. Job originators should be relieved of the need to remember job page numbers and other print parameters, like duplex status, etc., that may need to be adjusted to make the print job come out correctly.
SUMMARY OF INVENTION
The present invention contemplates the display of a print job as a sequence of pages and facilitates operator understanding of the final print job presentation by enabling the creation of what are here called artificial pages representing such elements as cover pages and preprinted sheets which are normally apart from the print job data file. The artificial pages are inserted into a display of the real pages defined by the print job data file or original document and are therefore displayed visually just as the other document pages are displayed. They can be manipulated just like other pages; that is, they can be moved, deleted, replaced and so on. The system remembers which pages are artificial and removes them from the document before printing and saving. All of this is transparent to the job originator.
In order to implement the invention, the job ticket records the information held by the artificial pages. Artificial pages are not tied to any particular real page; they are pages in their own right.
The present invention reduces job ticket errors and increases ticketing speed because it uses an intuitive visual feedback method to confirm the job ticket originator's intent. Preprinted sheets and covers have a certain order and appearance when printed; the invention presents the same order and appearance to the job originator during the ticketing process so the job ticket originator can see the end result before submitting the job.
BRIEF DESCRIPTION OF DRAWINGS
Some of the purposes of the invention having been stated, others will appear as the description proceeds, when taken in connection with the accompanying drawings, in which:
FIG. 1 is a schematic representation of an information handling system and associated printer in which the present invention is implemented.
FIGS. 2 , 3 and 4 are schematic representations of displays generated during exercise of the present invention.
FIG. 5 is a schematic representation of the steps of the method of the present invention, in flowchart form.
FIG. 6 is an illustration of a computer readable medium bearing program instructions effective when executing to implement the present invention.
DETAILED DESCRIPTION
While the present invention will be described more fully hereinafter with reference to the accompanying drawings, in which a preferred embodiment of the present invention is shown, it is to be understood at the outset of the description which follows that persons of skill in the appropriate arts may modify the invention here described while still achieving the favorable results of the invention. Accordingly, the description which follows is to be understood as being a broad, teaching disclosure directed to persons of skill in the appropriate arts, and not as limiting upon the present invention.
Referring now to FIG. 1 , an information handling system implementing the present invention is there shown at 10 with an associated high feature printer 11 . The system 10 has a processor 12 , associated memory 14 , and a display 15 . Appropriate operator manipulated input devices such as a keyboard or pointing device are provided as well known in the applicable arts, but are not illustrated as being well, known. By using the input devices, an operator may cause the system 10 to retrieve and execute programs and operate on data files which may be stored in the memory 14 or otherwise be accessible to the processor 12 as through a network, from a removable disk or the like.
FIGS. 2 through 4 are representations of displays created on the display 15 by execution of programs by the system 10 and illustrate certain distinguishing characteristics of the present invention. In particular, common reference characters are used in the successive Figures to denominate the same element, for ease in understanding. Displayed on the display 15 are a succession of pages as described more fully hereinafter. The display provides the end user interface which accomplishes the purposes of the present invention.
In FIG. 2 , the display 15 presents a sequence of pages 20 , 21 , 22 , 23 which are defined by the print job data file and are denominated in the discussion above as original or real pages.
In FIG. 3 , the display 15 presents the sequence of pages shown In FIG. 2 with the addition of two artificial pages 30 , 31 . As here shown, the artificial page 30 may be a preprinted page which is to appear between real pages 21 and 23 . In that position, the page 30 may be a preprinted divider, special graphics page, or the like. The other artificial page 31 is a cover page. It will be apparent that the plurality of pages may be more than two and that such pages may be distributed among the sequence of pages shown in FIG. 2 .
However, if the first mentioned page 30 were, for example, a second cover page to appear at the beginning of the sequence, then the operator could reposition the page to the beginning of the sequence as shown in FIG. 4 .
As suggested in the immediately preceding discussion, the present invention enables automatic creation of new pages (referred to as “artificial”) that are equivalent in size to the selected media associated with the new pages. Artificial pages are marked as such with text on the page (e.g., “[inserted sheet:StockA]” or “[cover:CoverStockB]”) that identifies the page as either a preprinted insert or a cover page. The invention contemplates that the page designation also includes the stock name to further identify the artificial page.
When a user creates, deletes, or moves an artificial page, the invention notes the change in the job ticket. The user treats artificial pages just like real pages. The user is unaware that the artificial page persists only in the job ticket and not in the original document.
The invention removes all artificial pages before saving the document, before printing the document, and before switching to another job ticket associated with this document. Then, the artificial pages are reapplied after saving, after printing, and after switching to a different job ticket. This way, the artificial pages are not actually stored or printed. Only the job ticket controls where artificial pages are placed.
Inserted sheets are always simplex and a change of media from surrounding pages. In a duplex print job, if the page before the insert was a front sheet side, it becomes a front sheet side with a blank back side. If the page after the insert was a back sheet side, it becomes a front sheet side, and the “sidedness” of subsequent pages is automatically changed to match.
In the preferred embodiment of the invention, inserted pages are numbered with a prefix like “Insert-N” where N is the number of the insert in the document. This leaves the original document page numbering alone so that the user can refer to original page numbers even after inserts are added. An alternative algorithm numbers inserted pages sequentially with the original pages.
The invention allows a user to turn the display of inserts on and off. When inserts are not displayed, which would appear similarly to FIG. 2 , the invention deletes the artificial pages from the document, restoring it to its original condition. Because the job ticket keeps track of the inserts locations, when the user changes the selection to display inserts the invention can create new artificial pages in the correct locations. When printing, the invention removes inserted pages and converts user-selected page ranges (including inserts) to real document page ranges (not including inserts).
If the alternate embodiment is being used and artificial pages are numbered sequentially with real pages, then the document page numbers change when inserts are shown or hidden, and any stored page ranges must change to match the new document numbering. This can be confusing, for example, to an operator who remembered a page range when inserts were shown and now tries to use the range when inserts are hidden. The confusion can be avoided by choosing a different numbering scheme for inserts and leaving original page numbering unaffected, as in the preferred embodiment.
When copying pages from a ticketed source document on disk into a destination document for printing, the invention allows users to specify page ranges including inserts, in which case inserted pages in the source page range are copied to the destination job ticket and the invention automatically adds the corresponding artificial pages to the destination document. The invention also allows users to specify page ranges without inserts, which correspond to the pages of the source document file without job ticketing. In this case, inserted pages that the source ticket identifies as being within the selected page range are optionally copied to the destination document. The invention prompts the user to select whether or not to include the inserted pages in the copy.
When replacing pages in a destination document with pages from a ticketed source document, the invention replaces the destination real pages with the source real pages, and adds any source inserts from the source page range to the destination ticket. Alternatively, the invention could treat the source page range (including inserts) as full pages and replace whatever destination pages (real or insert) with the source pages (real or insert).
Cover sheets are always simplex if preprinted. The invention allows covers to be printed on the front, on the back, or on both sides, in which cases one or two real pages from the document are included as the cover media. When the user selects a particular cover attribute, the invention automatically inserts an artificial page for a preprinted cover, or changes the page attributes of real pages for a print side X choice. Once pages are marked as covers, if the user moves, deletes, inserts or replaces cover pages, the cover attributes are now invalid and the invention removes them (with appropriate warning to the user about what it is doing). The preprinted cover page becomes a simple inserted page, and the real pages become simple page exceptions to choose new media. Alternately, the preprinted cover page could be deleted and the real pages become body pages when the cover attributes are removed.
Program instructions implementing the present invention as here described and shown may be distributed on computer readable media such as the disc 35 shown in FIG. 6 and , when executing on a processor, will follow the steps shown in FIG. 5 .
In the drawings and specifications there has been set forth a preferred embodiment of the invention and, although specific terms are used, the description thus given uses terminology in a generic and descriptive sense only and not for purposes of limitation. | A print job is displayed as a sequence of pages. An operator is enabled to create artificial pages representing such elements as cover pages and preprinted sheets which are normally apart from the print job data file. The artificial pages are inserted into a display of the real pages defined by the print job data file or original document and are therefore displayed visually just as the other document pages are displayed. They can be manipulated just like other pages; that is, they can be moved, deleted, replaced and so on. | 6 |
BACKGROUND
[0001] 1. Field
[0002] The embodiments are generally directed to managing memory, and more specifically to managing memory among heterogeneous computer components.
[0003] 2. Background Art
[0004] A computing device generally includes one or more processing units (e.g., a central processing unit (CPU), a graphics processing unit (GPU), a general purpose GPU (GPGPU), an accelerated processing unit (APU), or the like), that access a shared main memory. The processing units may execute programs (e.g., instructions or threads) that result in accesses to main memory. Because memory accesses may traverse a memory hierarchy including levels of cache and main memory, memory accesses may have different latencies, and may be performed in a different order than what was intended by the programs. In addition there may be conflicts, e.g., when two memory accesses attempt to store data in the same memory location.
[0005] Memory accesses are also called memory events, and examples include a store event (i.e., a memory access request to write data to main memory), a load event (i.e., a memory access request to read data from main memory), and synchronization events that are used to order conflicting memory events.
[0006] Memory consistency models provide rules for ordering memory events. A type of memory consistency model, release consistency with special accesses sequentially consistent (RCsc), provides a framework for event ordering for parallel programs with synchronization. Current systems that implement an RCsc memory model, a write-through (WT) memory system and a write-combining (WC) memory system, have difficulty with synchronization events such as a store release (StRel) synchronization event.
[0007] A StRel synchronization event is a release synchronizing store instruction that acts like an upward memory fence such that prior memory operations are visible to threads that share access to the ordering point before the store event portion of the StRel completes. A load acquire (LdAcq) synchronization event is a synchronizing load instruction that acts as downward memory fence such that later operations cannot occur before the LdAcq operation.
[0008] Upon executing a StRel synchronization event in a WT memory system, data is immediately written-through to main memory which is an inefficient use of the precious bandwidth resources to main memory. In addition, the system tracks acknowledgements for individual store completions which is highly inefficient. Further, upon receiving a load acquire synchronization event, the system performs a full cache flush to invalidate clean and potentially stale data which makes data reuse in the presence of synchronization impossible.
[0009] The WC memory system uses cache hierarchies to coalesce store events. Executing a StRel synchronization event in the WC triggers a slow and intensive cache flush to determine when the prior stores have completed to a next level of hierarchy. A cache flush entails walking through an entire cache hierarchy to track outstanding store events to completion.
[0010] In addition, write-combining caches incur overhead to track dirty bytes in cache lines in the memory hierarchy.
[0011] A hierarchical directory/snooping cache coherence protocol solution is a “read for ownership” solution that could support an RCsc memory consistency model, however, the memory access requests to write data encounter long delays. A requesting processor (e.g., a CPU or GPU) has to read or own a memory block before writing to local cache and completing a store event.
BRIEF SUMMARY OF EMBODIMENTS
[0012] What is needed therefore, are approaches that enforce an RCsc memory model and can execute release synchronization instructions such as a StRel event without tracking an outstanding store event through a memory hierarchy, while efficiently using bandwidth resources. In embodiments, a requesting processor does not have to read or own a memory block before writing in local cache and completing a store event. Certain embodiments may, in certain conditions, improve the performance of both global synchronization events (e.g., writing to main memory for completion) and local synchronization events (e.g., writing to a common ordering point such as level 2 cache for completion) since the cache hierarchy does not need to be flushed and a store event may not need to reach main memory to complete. Further embodiments include decoupling a store event from an ordering of the store event with respect to a RCsc memory model.
[0013] Certain embodiments include a method, computer program product, and a system. For example, a system embodiment includes a set of hierarchical read-only cache and write-only combining buffers that coalesce stores from different parts of the system. In addition, a component maintains a partial order of received store events and release synchronization events to avoid content addressable memory (CAM) structures, full cache flushes, and direct write-throughs to memory. Some embodiments provide RCsc memory model programmability while efficiently using limited bandwidth.
[0014] Certain embodiments further include a read-only cache and a write-only combining cache at respective levels in the memory hierarchy to reduce the overhead in managing the write-combining cache. Data written to cache as a result of a store event for example, is called dirty data, and is different than the data that resides in the location in main memory. Dirty data is eventually written to main memory.
[0015] Certain embodiments also include a method for receiving a memory event. When the memory event is a store event, the method further includes: writing a first data to a write-only, level n cache, where n is an integer representing the level of cache hierarchy. The method further includes writing, to a level n pool, a store entry that includes an address of the first data in the level n cache, where the level n pool maintains a partial order among the store entry, a prior received store entry, and a release marker entry, and when a release marker is present, ordering the store entry in the level n pool to follow a most-recent release marker. When the memory event is a load event, the method further includes searching a read-only, level n cache for a second data, and determining when the second data is present in a corresponding write-only, level n cache.
[0016] A further embodiment includes a computer program product having instructions stored thereon, where the execution of the stored instructions results in a processing unit causes the following steps to be performed. First, a memory event is received. When the memory event is a store event, the next step includes writing a first data to a write-only, level n cache, where n is an integer representing the level of cache hierarchy. Subsequent steps include writing, to a level n pool, a store entry that includes an address of the first data in the level n cache, where the level n pool maintains a partial order among the store entry, a prior received store entry, and a release marker entry, and when a release marker is present, ordering the store entry in the level n pool to follow a most-recent release marker. When the memory event is a load event, the next step includes searching a read-only, level n cache for a second data, and determining when the second data is present in a corresponding write-only, level n cache.
[0017] Another embodiment includes a processing unit configured to perform the following functionality. First, the processing unit receives a memory event. When the memory event is a store event, the processing unit writes a first data to a write-only, level n cache, where n is an integer representing the level of cache hierarchy. Subsequently, the processing unit writes to a level n pool a store entry that includes an address of the first data in the level n cache, where the level n pool maintains a partial order among the store entry, a prior received store entry, and a release marker entry, and when a release marker is present, orders the store entry in the level n pool to follow a most-recent release marker. When the memory event is a load event, the processing unit searches a read-only, level n cache for a second data, and determines when the second data is present in a corresponding write-only, level n cache.
[0018] Further features and advantages of the embodiments, as well as the structure and operation of various embodiments, are described in detail below with reference to the accompanying drawings. It is noted that the embodiments are not limited to the specific embodiments described herein. Such embodiments are presented herein for illustrative purposes only. Additional embodiments will be apparent to persons skilled in the relevant art(s) based on the teachings contained herein.
BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES
[0019] The accompanying drawings, which are incorporated herein and form part of the specification, illustrate the embodiments and, together with the description, further serve to explain the principles of the embodiments and to enable a person skilled in the pertinent art to make and use the embodiments. Various embodiments are described below with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout.
[0020] FIG. 1 illustrates an APU environment, according to an embodiment.
[0021] FIG. 2 illustrates a write-back write-combine system, according to an embodiment.
[0022] FIG. 3A illustrates a GPU with separate read-only cache and write-only cache, according to an embodiment.
[0023] FIG. 3B illustrates a GPU with separate read-only cache, write-only cache, and dirty read buffers (DRBs) according to an embodiment.
[0024] FIG. 4 illustrates a method of handling the receipt of memory events, according to an embodiment.
[0025] FIG. 5 illustrates a method of evicting entries, according to an embodiment.
[0026] FIG. 6 illustrates a method of handing memory synchronization events, according to an embodiment.
[0027] FIG. 7 illustrates a method of evicting entries from a queue, according to an embodiment.
[0028] FIG. 8 illustrates an example computer system in which embodiments may be implemented.
[0029] The embodiments will be described with reference to the accompanying drawings. Generally, the drawing in which an element first appears is typically indicated by the leftmost digit(s) in the corresponding reference number.
DETAILED DESCRIPTION OF EMBODIMENTS
[0030] In the detailed description that follows, references to “one embodiment,” “an embodiment,” “an example embodiment,” etc. indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.
[0031] The term “embodiments” does not require that all embodiments include the discussed feature, advantage or mode of operation. Alternate embodiments may be devised without departing from the scope of the disclosure, and well-known elements of the disclosure may not be described in detail or may be omitted so as not to obscure the relevant details. In addition, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. For example, as used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
[0032] Computing devices process data and provide many applications to users. Example computing devices include, but are not limited to, mobile phones, personal computers, workstations, and game consoles. Computing devices use a central processing unit (“CPU”) to process data. A CPU is a processor which carries out instructions of computer programs or applications. For example, a CPU carries out instructions by performing arithmetical, logical and input/output operations. In an embodiment, a CPU performs control instructions that include decision making code of a computer program or an application, and delegates processing to other processors in the electronic device, such as a graphics processing unit (“GPU”).
[0033] A GPU is a processor that is a specialized electronic circuit designed to rapidly process mathematically intensive applications (e.g., graphics) on electronic devices. The GPU has a highly parallel structure that is efficient for parallel processing of large blocks of data, such as mathematically intensive data common to computer graphics applications, images and videos. The GPU may receive data for processing from a CPU or generate data for processing from previously processed data and operations. In an embodiment, the GPU is a hardware-based processor that uses hardware to process data in parallel.
[0034] Due to advances in technology, a GPU also performs general purpose computing (also referred to as GPGPU computing). In the GPGPU computing, a GPU performs computations that traditionally were handled by a CPU. An accelerated processing unit (APU) includes at least the functions of a CPU and a GPU. The GPU can be a GPGPU.
[0035] In an embodiment, a GPU includes one or more compute units (CUs) that process data. A compute unit (CU) includes arithmetic logic units (ALUs) and other resources that process data on the GPU. Data can be processed in parallel within and across compute units.
[0036] In an embodiment, a control processor on a GPU schedules task processing on compute units. Tasks include computation instructions. Those computation instructions may access data stored in the memory system of a computing device and manipulate the accessed data. In an embodiment, the data may be stored in volatile or non-volatile memory. An example of volatile memory includes random access memory (RAM). Examples of RAM include dynamic random access memory (DRAM) and static random access memory (SRAM). Volatile memory typically stores data as long as the electronic device receives power. Examples of non-volatile memory include read-only memory (ROM), flash memory, ferroelectric RAM (F-RAM), hard disks, floppy disks, magnetic tape, optical discs, etc. Non-volatile memory retains its memory state when the electronic device loses power or is turned off.
[0037] FIG. 1 illustrates an APU environment, according to an embodiment. In the example shown, system 100 is an APU environment that includes CPU 110 , GPU 130 , main memory 150 , and bus 140 .
[0038] Bus 140 may be any type of communication infrastructure used in computer systems, including a peripheral component interface (PCI) bus, a memory bus, a PCI Express (PCIE) bus, front-side bus (FSB), hypertransport (HT), or another type of communication structure or communications channel whether presently available or developed in the future.
[0039] FIG. 2 illustrates a write-combining (WC) system, according to an environment. WC System 200 includes a conventional GPU and bus 140 . WC System 200 includes CUs 210 a and 210 b , and a multi-tiered write-combining cache including Level 1 (L1) caches 220 a and 220 b , as well as Level 2 (L2) cache 240 . L2 cache 240 is shared among CUs 210 in system 200 . Bus 230 is substantially the same as bus 140 of FIG. 1 .
[0040] In WC System 200 , write-combining caches provide coherence for data-race-free programs (e.g., programs free of memory accesses conflicts) by writing updates to an ordering point (e.g., L2 cache 240 or main memory 150 ) at synchronization events. In addition, write-combining caches use a write-back policy that keeps previously written data in cache longer than the WT alternative. This policy increases the chance that the results of two store events coalesce in cache before consuming the limited bandwidth at a synchronization event to evict the data to a next-level cache in the memory hierarchy. However, the cost of a synchronization event in WC System 200 is high. Upon execution of a StRel synchronization event, for example, WC System 200 must perform a full cache flush to find and flush outstanding writes throughout the cache hierarchy to completion to ensure proper ordering of memory events. A write is data written by a store event. WC System 200 searches L1 caches 220 a and 220 b as well as L2 cache 240 to find data previously written, also called dirty data. Once dirty data is found, WC System 200 evicts the dirty data to a next level of cache hierarchy, or main memory 150 if a next-level cache is not present, and waits for acknowledgements to be received before processing another memory event. The cache flush process is a very slow and tedious process to be avoided.
[0041] Embodiments utilize separate read-only cache and write-only combining caches to enforce a RCsc model, and avoid tracking outstanding store events via the memory hierarchy. Embodiments utilize extra knowledge to manage a partial order of outstanding writes and release synchronization events separately from the outstanding writes that move through a memory hierarchy. Because store events are not tracked via the memory hierarchy, acknowledgement messages are not needed for store event completions resulting in reduced traffic. In addition, embodiments allow a store event to complete without having to write-through to main memory 150 .
[0042] A memory fence is an operation used to delay a memory access until the previous memory access has been performed. Synchronization events utilize memory fences to provide order by making results visible (i.e., available for reading) in a globally shared memory so that other instructions in the computing device may utilize the results.
[0043] The RCsc consistency model requires that prior store events that occur before a StRel synchronization event be visible (i.e., readable) in a specified scope (e.g., global or local) and that loads after a LdAcq appear to be executed after the LdAcq. Also, the LdAcqs and StRels themselves obey sequential consistency so a StRel needs to complete the writes before a LdAcq may proceed to read the writes.
[0044] A scope is a group of threads that access a shared memory or a common ordering point. Global scope requires global synchronization and a store event is complete when the data written in main memory 150 is visible to other threads in the system. Local scope requires local synchronization and a store event is complete when the data is written to a common ordering point such as a level 2 cache, and is visible to threads that share access to that common ordering point. The ability to synchronize to a local scope when possible, instead of having to synchronize to a global scope provides considerable savings with regards to limited bandwidth access to main memory, reduced latency, and power savings.
[0045] In write-combining caches, store events are more costly to support than load events because a write-combining cache allows partial cache line writes without exclusive ownership (i.e., allows multiple writers). A system tracks dirty bytes within a cache line to merge writes to different bytes of the same cache line. Most implementations use a respective dirty byte bitmask for a cache line (e.g., 12.5% overhead for 64-byte cache lines) and write out the dirty portions of a cache line on evictions. Thus, write-combining caches incur overhead for implementing a respective dirty byte mask for a cache line in the memory hierarchy.
[0046] Typically, in current GPU and GPGPU applications, the number of load (read) events vastly outnumber store (write) events. And among the store events, a small subset require intermediate visibility before being written to main memory 150 . Thus, the number of read-after-write (RAW) operations is relatively small.
[0047] Embodiments reduce the overhead by splitting a write-combining cache at one or more levels into a read-only cache and a write-only combining cache. Because the number of reads is larger than the number of writes, the read-only cache can be larger and the write-only cache can be smaller. The separation of the read-only and write-only cache encourages data path optimizations such as independent and lazy management of write bandwidth while minimizing implementation complexity. And, as GPU threads seldom perform RAW operations, the potential costs of the separation are low.
[0048] In an embodiment, a special victim buffer called a dirty read buffer (DRB) can be used to provide dirty bit masks on the smaller write-only cache. The DRB keeps track of writes (dirty data) in the write-only cache and sources requests to read dirty data in the write-only cache (i.e., a RAW operation). As RAW operations are infrequent, the DRB is a simple implementation that separates the read-only and write-only operations.
[0049] FIG. 3A illustrates a GPU with separate read-only cache and write-only combining cache, according to an embodiment. System 300 includes a memory hierarchy of read-only caches rL1 370 a , rl1 370 b , and rL2 380 , write-only combining buffers wL1 320 a , wL1 320 b , and wL2 340 , corresponding co-located pool components L1 pool 350 a , L1 pool 350 b and L2 pool 360 , as well as compute units CU 310 a and CU 310 b.
[0050] A read-only cache is also called clean cache and contains data identical to the location in main memory 150 . A read-only cache includes at least one of but is not limited to an address that corresponds to a memory location in main memory, a cache tag, a partial address, a cache line, and an indication of whether the cache line or bytes of the cache line are invalid. The bytes are invalid if the bytes are written to a corresponding write-only cache. To search for a cache line in a cache, a system may search for at least one of an address, a cache tag, or a partial address of the cache line.
[0051] An example of the indication can include a write-only, cache-present bit. When set, the write-only, cache-present bit indicates, for example, that dirty data (i.e., newly written data will be written to main memory 150 ) exists in the corresponding write-only cache for the same cache line. When clear, the write-only, cache-present bit indicates, for example, that no dirty data exists in the corresponding write-only cache for the same cache line.
[0052] The write-only cache can be much smaller than the read-only cache, contains dirty data, i.e., the write-only cache contains data that is different to the location in main memory 150 as it has not yet been written to main memory 150 . A write-only cache includes at least one of but is not limited to an address that corresponds to a memory location in main memory, a cache tag, a partial address, and a dirty byte bitmask.
[0053] Pool components contain knowledge to track outstanding store events separately from the ordering of store events in the memory hierarchy that occurs when enforcing an RCsc memory model. Pool components L1 pool 350 a , L1 pool 350 b , and L2 pool 360 contain knowledge that enables system 300 to track which prior writes and corresponding addresses that may not yet be written back to main memory 150 , without having to perform a cache walk, or implementing power-hungry CAM lookups to track acknowledgements.
[0054] Pool components L1 pool 350 a , L1 pool 350 b , and L2 pool 360 may be implemented for example, by a synchronization First In First Out (S-FIFO) or a Bloom-filter with signatures as are well known in the art. A pool component may contain entries associated with a store event or a release synchronization event. An entry associated with a store event may include but is not limited to an address in main memory and a thread identity of a store event. A thread identity is used to recognize different threads. An entry associated with a release synchronization event is a release marker that may include but is not limited to a thread identity of a release synchronization event.
[0055] The pool and write-only combine cache do not require inclusion. That is, the write-only cache does not need to contain the data associated with all entries in the pool. For example, some data may be evicted early due to cache replacement policies or a load event with a partial hit that causes an early data eviction.
[0056] FIG. 3B illustrates a GPU with separate read-only cache, write-only cache, and dirty read buffers (DRBs) according to an embodiment. A dirty read buffer (DRB) may be collocated with a write-only and read-only cache at a corresponding level and the DRB is used to maintain a separation among read-only cache and write-only cache. A DRB may include but is not limited to include an address, and an indication of the dirty bytes in the write-only cache. In addition to the elements shown in FIG. 3A , FIG. 3B includes DRB 1 375 a and DRB1 375 b , as well as DRB2 385 .
[0057] When a DRB is present, a read-only cache includes at least one of but is not limited to an address that corresponds to a memory location in main memory, a cache tag, a partial address, and a cache line. Unlike FIG. 3A , an indication of whether the cache line or bytes of the cache line are invalid (e.g., write-only, cache-present bit) is not necessary in the read-only cache as the information is found in the corresponding DRB, and reads to the read-only cache and the corresponding DRB can occur in parallel. When the address is found in the DRB, any corresponding data also found in the read-only cache is considered invalid. Bytes in the read-only cache are invalid if new data is written to the address of the bytes in a corresponding write-only cache. To search for a cache line in a cache, a system may search for at least one of an address, a cache tag, or a partial address of the cache line.
[0058] FIG. 4 illustrates a method of handling the receipt of memory events, according to an embodiment. In one example, system 100 and system 300 may be used to demonstrate method 400 . It is to be appreciated that operations in method 400 may be performed in a different order than shown, and method 400 may not include all operations shown. For ease of discussion, and without limitation, method 400 will be described in terms of elements shown in FIG. 1 , FIG. 3A , and FIG. 3B .
[0059] Method 400 begins at step 410 and proceeds to step 415 .
[0060] At step 415 , memory events such as a store, a load, or a release synchronization are received from a compute unit such as CU 310 a . The memory events are read from a software program e.g., instruction code, in program order.
[0061] When a load event is received, at step 420 , method 400 looks for the address of the data in rL1 370 a and checks the write-only, cache-present bit. Method 400 proceeds to step 425 .
[0062] At step 425 , if the data is found in rL1 370 a (a hit), and the write-only, cache-present bit is clear, the data is read and method 400 returns to step 415 to await another memory event. The write-only, cache-present bit being clear indicates that there is no dirty data in the corresponding wL1 320 a waiting to be written to main memory 150 and thus the data in rL1 370 is not stale.
[0063] At step 425 , when the write-only, cache-present bit is set, (i.e., dirty data for the cache line is present in wL1 320 a ) wL1 320 a is checked to see if the load event can be fully satisfied by the dirty bytes present. If the data is found in wL1, 320 a , the load event (read) is completed and method 400 proceeds to step 415 .
[0064] At step 425 , if the data is not found in rL1 370 a (a miss), and the write-only, cache-present bit is clear, method 400 proceeds to step 427 . Also, if a L2 memory hierarchy is not present, method 400 proceeds to step 430 .
[0065] At step 425 , when there is a partial hit in wL1 320 a , for example, the write-only, cache-present bit is set, some of the data is found in wL1 320 a , and a Level-2 memory hierarchy is not present, the dirty bytes are written through from wL1 320 a to main memory 150 (not shown). Method 400 proceeds to step 430 .
[0066] At step 425 , if the data is partially found in wL1 320 a , the dirty data in wL1 320 a is written to wL2 340 . The read request is sent to the next level of the memory hierarchy to L2 cache hierarchy. Method 400 proceeds to step 427 . As noted earlier, a partial hit is an infrequent occurrence due to the low number of RAW operations.
[0067] At step 427 , method 400 looks for the data, or the remaining data in the case of a partial hit, in rL2 380 ; if the data or the remaining data is found in rL2 380 (a hit), and the write-only, cache-present bit is clear, the data is read from rL2 380 and method 400 returns to step 415 to await another memory event.
[0068] At step 427 , if the data is not found in rL2 380 (a miss) and the write-only, cache-present bit is clear, method 400 proceeds to step 430 .
[0069] At step 427 , when the write-only, cache-present bit is set, (i.e., dirty data for the cache line is present in wL2 340 ) wL2 340 is checked to see if the load event can be fully satisfied by the dirty bytes present. If the data is found in wL2 340 , the read is completed and method 400 proceeds to step 415 .
[0070] At step 427 , when the write-only, cache-present bit is set and the data is partially found and read from wL2 340 (a partial hit), the dirty data in wL2 340 is written to main memory 150 . Data at rL1 370 a and rL1 370 b with that address are invalidated, and method 400 proceeds to stop 430 .
[0071] At step 430 , the data is read from main memory 150 . Method 400 proceeds to step 415 .
[0072] In an embodiment, DRBs are implemented at corresponding levels of the memory hierarchy. Method 400 begins at step 410 and proceeds to step 415 .
[0073] When a load event is received, at step 420 , method 400 looks for the address of the data in parallel in rL1 370 a and DRB1 375 a . Method 400 proceeds to step 425 .
[0074] At step 425 , if the data is found in rL1 370 a (a hit), and not in DRB1 375 a , the data is read and method 400 returns to step 415 to await another memory event.
[0075] At step 425 , when the address is found in DRB1 375 a , (i.e., dirty data for the cache line is present in wL1 320 a ) DRB1 375 a is checked to see if the load event can be fully satisfied by the dirty bytes present. If the data is found in DRB1 375 a , the load event (read) is completed and method 400 proceeds to step 415 .
[0076] At step 425 , if the data is not found in rL1 370 a (a miss), or DRB1 375 a , method 400 proceeds to step 427 . Also, if a L2 memory hierarchy is not present, method 400 proceeds to step 430 .
[0077] At step 425 , when there is a partial hit in DRB1 375 a , for example, some of the data is found in DRB1 375 a , and a Level-2 memory hierarchy is not present, the dirty bytes are written through from wL1 320 a to main memory 150 (not shown). Method 400 proceeds to step 430 .
[0078] At step 425 , if the data is partially found in DRB1 375 a (a partial hit), the dirty data in wL1 320 a is written to wL2 340 . The read request is sent to the next level of the memory hierarchy to L2 cache hierarchy. Method 400 proceeds to step 427 .
[0079] At step 427 , method 400 looks for the data, or the remaining data in the case of a partial hit, in parallel in rL2 380 and DRB2 385 ; if the data or the remaining data is found in rL2 380 (a hit), but not in DRB2 385 , the data is read from rL2 380 and method 400 returns to step 415 to await another memory event.
[0080] At step 427 , if the data is not found in rL2 380 (a miss) or DRB2 385 , or if L2 memory hierarchy is not present, method 400 proceeds to step 430 .
[0081] At step 427 , the address is found in DRB2 385 (i.e., dirty data for the cache line is present in wL2 340 ) DRB2 385 is checked to see if the load event can be fully satisfied by the dirty bytes present. If the data is found in DRB2 385 , the read is completed and method 400 proceeds to step 415 .
[0082] At step 427 , when the address is found in DRB2 385 and the data is partially found and read from DRB2 385 (a partial hit), the dirty data in wL2 340 is written to main memory 150 . Data at rL1 370 a and rL1 370 b with that address are invalidated, and method 400 proceeds to stop 430 .
[0083] At step 430 , the data is read from main memory 150 . Method 400 proceeds to step 415 .
[0084] When a store event is received at step 415 , method 400 proceeds to step 435 .
[0085] At step 435 , method 400 writes the data affiliated with an address to wL1 320 a and the data is called dirty data as it is not the same as the memory location at the same address in main memory 150 . The dirty byte bitmask of wL1 320 a is updated to indicate the dirty bytes of cache line associated with the address. In addition, method 400 checks to see if the address is found in rL1 370 a . When the address is found in rL1 370 a , method 400 sets a flag of a cache tag, to indicate that updated data is in the wL1 320 a (e.g., sets the write-only, cache-present bit in the rL1 370 a ). The store operation completes immediately.
[0086] In an embodiment, when a DRB is implemented, e.g., DRB1 375 a , the dirty byte bitmask of DRB1 375 a would be updated. In an embodiment, the write-only, cache-present bit would not be needed in rL1 370 a as the read to rL1 370 a can occur in parallel as a read to DRB1 375 a.
[0087] While the DRB example is not propagated throughout the rest of the specification, one skilled in the art can readily understand how a DRB could be implemented accordingly.
[0088] At step 440 , a store entry is written to L1 pool 350 a that can include but is not limited to the address location in main memory 150 to which the data is to be written, and a thread identity. A thread is a work item involved with the current instruction execution that includes the store event. The L1 pool 350 a maintains a partial order among the store entry, any prior received store entries that may exist, and any release marker entries.
[0089] In an example, two groups of prior store entries may exist in L1 pool 350 a that are separated by a release marker described below. While no particular order within a group of prior store entries exists, the first group of prior store entries is ordered to be evicted before the release marker, and the second group is ordered to be evicted after the release marker. Thus there is partial order in the pool.
[0090] The store entry is written in L1 pool 350 a to follow the most-recent release marker. In the example, the store entry would be added to the second group of existing prior store entries in no particular order.
[0091] Method 400 proceeds to step 415 .
[0092] When a release synchronization event such as a release, a StRel, a fence, a kernel end, or a barrier operation is received at step 415 , method 400 proceeds to step 445 . A release marker is written to L1 pool 350 a and ordered to follow any prior write entries in L1 pool 350 a . The entry of the release marker in L1 pool 350 a triggers eviction of any prior write entries from the L1 pool 350 a . Thus, the release marker will be evicted after the prior entries in L1 pool 350 a to ensure proper visibility of prior writes.
[0093] At step 450 , if the release synchronization event is a StRel, method 400 proceeds to step 455 . At step 455 , method 400 writes data associated with the store event portion of the StRel to wL1 320 a . At step 460 , a corresponding store entry associated with the store event portion of the StRel is made to L1 pool 350 a and ordered to follow the most-recent release marker. The store entry includes an address location in main memory 150 to which the data is to be written, and a thread identity, for example. Method 400 checks to see if the address is found in rL1 370 a . When the address is found in rL1 370 a , method 400 sets the write-only, cache-present bit in the rL1 370 a ; the write-only, cache-present bit may be a bit or a flag in for example, a cache tag, that indicates that updated data is in the wL1 320 a . The method proceeds to step 415 .
[0094] At step 450 , if the release synchronization event is not a StRel, method 400 proceeds to step 415 .
[0095] FIG. 5 illustrates a method of evicting entries, according to an embodiment. In one example, system 100 and system 300 may be used to demonstrate method 500 . It is to be appreciated that operations in method 500 may be performed in a different order than shown, and method 500 may not include all operations shown. For ease of discussion, and without limitation, method 500 will be described in terms of elements shown in FIG. 1 and FIG. 3 .
[0096] Method 500 depicts the flow of operations when evictions from a pool occur. Evictions can occur, for example, when the number of entries in a pool exceeds a settable maximum value, or when a release marker is added to the pool and triggers prior write evictions. Method 500 includes operations at the L1 pool 350 a and L2 pool 360 , for example.
[0097] Method 500 begins at step 510 and proceeds to step 515 .
[0098] At step 515 , method 500 proceeds to step 520 to depict L1 pool 350 a eviction operations.
[0099] At step 520 , method 500 determines whether L1 pool 350 a evicts a store entry or a release marker entry.
[0100] If a release marker is present in L1 pool 350 a and no prior writes exist ahead of the release marker entry, method 500 determines to evict a release marker entry and proceeds to step 525 .
[0101] At step 525 , the release marker is evicted from L1 pool 350 a to L2 pool 360 . The release marker is ordered to follow any prior store entries in L2 pool 360 . The addition of the release marker triggers evictions of any prior store entries from L2 pool 360 , before the eviction of the release marker from L2 pool 360 . When a L2 memory hierarchy is not present, the release marker is evicted from L1 pool 350 a , and an acknowledgement is sent to the originating thread that the release is complete.
[0102] Method 500 proceeds to step 545 .
[0103] At step 520 , if a release marker is present in L1 pool 350 a , the prior store entries in L1 pool 350 a ahead of the release marker are determined to be evicted to a L2 pool 360 , and corresponding data in wL1 320 a are correspondingly evicted to wL2 340 . The prior store entries can be evicted in any order with respect to prior store entries. But, prior store entries and corresponding data in wL1 320 a are evicted before the oldest release marker is evicted. Thus, the written data is guaranteed to be at the next level of the hierarchy by the time the release marker is evicted.
[0104] At step 520 , if L1 pool 350 a is determined to evict a store entry, method 500 proceeds to step 530 .
[0105] At step 530 , method 500 determines if the corresponding data exists in the wL1 320 a . If the corresponding data does not exist, method 500 proceeds to step 535 . At step 535 , a cache replacement policy as is well known in the art, may be enforced and previously evicted the data from wL1 320 a ; the store entry in L1 pool 350 a is evicted to L2 pool 360 . In addition, a special case of a load event with a partial hit may also cause an early data eviction. Thus, embodiments support early evictions from the memory hierarchy. Method 500 proceeds to step 545 .
[0106] At step 530 , if the corresponding data does exist in the wL1 320 a , method 500 proceeds to step 540 .
[0107] At step 540 , the store entry in L1 pool 350 a is evicted to L2 pool 360 . In addition, the corresponding data in L1 cache 320 a is evicted to wL2 340 .
[0108] When a L2 cache hierarchy is not present (not shown), embodiments include the following: evicting the prior store entry from the L1 pool 350 a ; evicting data, when present, from the wL1 320 a associated with the evicted prior store entry to main memory; when the evicted prior store entry is associated with a StRel release synchronization event, signaling completion of release to the originating thread.
[0109] When a L2 cache hierarchy is present and the L2 cache hierarchy is an ordering point (not shown), embodiments further include the following: evicting the prior store entry from L1 pool 350 a ; evicting data, when present, from the wL1 320 a associated with the evicted prior store entry to the ordering point; when the evicted prior store entry is associated with a StRel release synchronization event, signaling completion of release to the originating thread. Thus, a StRel can complete at an ordering point other than main memory, and local synchronization is possible (e.g., receipt of a LdAcq can complete at wL2 340 without having to access main memory 150 ). Note that main memory 150 can also be an ordering point and would be a global ordering point.
[0110] Method 500 proceeds to step 545 .
[0111] At step 515 , method 500 proceeds to step 545 to depict L2 pool 360 eviction operations.
[0112] At step 545 , method 500 determines whether L2 pool 360 evicts a store entry or a release marker entry. Evictions may occur when a release marker entry is added to L2 pool 360 that triggers evictions, or when the number of L2 pool 360 entries exceeds a configurable threshold, for example. If L2 pool 360 evicts a release marker entry, method 500 proceeds to step 550 .
[0113] At step 550 , the release marker is evicted from L2 pool 360 . In addition, method 500 transmits an acknowledgment to the originating thread or original requester, CU 310 a , that the release event is complete. The release completion provides assurance that safe forward progress is possible beyond the release synchronization event.
[0114] Note that for a StRel release synchronization event, CU 310 a does not need to wait for the acknowledgement, but rather CU 310 a can continue processing other memory events until executing the next LdAcq. But, for barrier and fence release synchronization events, CU 310 a waits until a corresponding acknowledgement is received. Further, additional embodiments enable unsynchronized stores, if allowed by the memory model. These unsynchronized stores would not generate a store entry in L1 Pool 350 a , rather, corresponding data could be written to wL1 320 a . Thus, unsynchronized stores would not load pool components with unnecessary operations.
[0115] The method proceeds to step 565 .
[0116] At step 545 , if L2 pool 360 evicts a store entry, method 500 proceeds to step 555 .
[0117] At step 555 , method 500 determines if the corresponding data exists in the wL2 340 . If the corresponding data does not exist, (e.g., due to a cache replacement policy enforcement) the store entry is evicted from L2 pool 360 and method 500 proceeds to step 565 .
[0118] At step 555 , if the corresponding data does exist, method 500 proceeds to step 560 .
[0119] At step 560 , the store entry is evicted from L2 pool 360 . In addition, the corresponding data in wL2 340 is evicted to main memory 150 . Further, if the data was from a store event portion of a StRel, method 500 signals completion of release to the originating thread.
[0120] Embodiments invalidate the data in rL1 370 a and rL1 370 b associated with the corresponding address. The invalidations may be completed by broadcasting invalidation messages to rL1 370 a and rL1 370 b caches, to ensure release consistency. The invalidations are not critical to performance as the invalidations merely delay release synchronization completions and are bound based on the number of entries in L2 pool 360 when a release synchronization event occurs. Note that write evictions and load requests do not stall waiting for invalidations. In addition, the data in rL1 370 a and rL1 370 b can be invalidated with a flash clear, e.g., when a LdAcq is received, all blocks in the cache are invalidated. The flash clear does not need to be associated with the corresponding address.
[0121] Method 500 proceeds to step 565 .
[0122] Logically, L1 pool 350 a , L1 pool 320 b , and L2 pool 360 may be implemented per thread identity or group of threads (e.g., wavefront identity).
[0123] FIG. 6 illustrates a method of handing memory synchronization events, according to an embodiment. In one example, system 100 and system 300 may be used to demonstrate method 600 . It is to be appreciated that operations in method 600 may be performed in a different order than shown, and method 600 may not include all operations shown. For ease of discussion, and without limitation, method 600 will be described in terms of elements shown in FIG. 1 and FIG. 3 .
[0124] The top portion of FIG. 6 includes an execution order of two threads, one from compute unit CU 310 a and another from CU 310 b , communicating a value in a simple system that contains one level of cache including wL1 320 a and wL1 320 b . The lower portion of FIG. 6 illustrates method 600 .
[0125] Method 600 begins at step 601 when CU 310 a issues a store event, ST X (1), and writes data, 1, to a cache block in a cache line of wL1 320 a , associated with address X in main memory 150 . In addition, a store entry is added to L1 pool 350 a that can include but is not limited to the address, X, associated with the data and a thread identity. If prior store entries are present, the new store entry is added to the group of prior store entries and no particular order is maintained. However, if a release marker is present, the new store entry would be ordered to follow the most-recent release marker. If prior store entries are present after the most-recent release marker, the new store entry would join that group and no particular order is maintained among the prior store entries.
[0126] At step 602 , CU 310 a issues a StRel synchronization event that triggers pool evictions through the memory hierarchy to main memory 150 . A release marker (Rel) entry is added to L1 pool 350 a , and is ordered to follow any prior store entries in L1 pool 350 a , to be evicted after the prior write entries in L1 pool 350 a are evicted.
[0127] At step 603 , L1 pool 350 a begins evicting prior write entries ordered before the release marker (Rel). The entry associated with address X is evicted from L1 pool 350 a , and the corresponding data in the cache in wL1 320 a associated with address X is evicted to main memory 150 .
[0128] At step 604 , the prior write entries have been evicted from L1 pool 350 a , the release marker (Rel) is evicted from L1 pool 350 a and an acknowledgement is sent to CU 310 a to signal that the release event portion of the StRel is complete.
[0129] At step 605 , CU 310 a issues the store event portion of the StRel synchronization event and writes data, 2, to a cache in wL1 320 a associated with address A. In addition, a L1 pool 350 a store entry is added that may include but is not limited to the address, A, associated with the cached data, and a thread identity. In an embodiment, an entry of the store event portion of a StRel to L1 pool 350 a will trigger L1 pool 350 a evictions.
[0130] At step 606 , the prior write associated with address A is eventually evicted from L1 pool 350 a (e.g., if the number of pool entries exceed a settable maximum value (not shown) or another release synchronization event occurs (not shown)). When the entry associated with address A is evicted from L1 pool 350 a , the data associated with address A in wL1 320 a is evicted to main memory 150 and signals completion of the release event portion of the StRel synchronization event to other threads in the system. The data at address A in main memory 150 is now visible to all threads in the system.
[0131] At step 607 , CU 310 b issues a load acquire LdAcq synchronization event to complete the synchronization. Method 600 searches wL1 320 b , to read the data at address A, and when the address A is not found (a miss), method 600 searches main memory 150 . When the address A and corresponding data, 2, are found and read from main memory 150 (a hit), the data is copied (i.e., loaded) to wL1 320 b and is transmitted to (i.e., read by) CU 310 b.
[0132] At step 608 , CU 310 b issues a load event and searches wL1 320 b , to read the data at address X, and when the address X is not found (a miss), method 600 searches main memory 150 . When the address X and corresponding data, 1, are found and read from main memory 150 (a hit), the data is copied to wL1 320 b and is read by CU 310 b.
[0133] In an embodiment, a pool can be implemented with a synchronization First In First Out (S-FIFO) that maintains complete order for prior writes as well as a release synchronization event. For example, at step 601 , when a store event occurs, an entry would be made to the tail of an S-FIFO that can include but is not limited to the address, X, associated with the data and a thread identity. If prior writes are present, the new L1 pool 350 a store entry would be added to the tail of the queue and complete order is maintained among the prior writes as well as the release synchronization events.
[0134] When the S-FIFO is filled, method 600 would begin to dequeue the S-FIFO. The dequeuing is similar to a pool component exceeding a settable maximum value. The entry at the top of the S-FIFO and the corresponding cache in the wL1 320 a would be evicted to the corresponding next-level S-FIFO and next-level cache, e.g. wL2 340 if present. If the next-level cache is not present, the entry at the top of the S-FIFO is removed (e.g., popped) and the corresponding data in wL1 320 a is written to main memory 150 .
[0135] Logically there can be a S-FIFO per thread, but physically the S-FIFO can be implemented as a single FIFO, or as many FIFOs that are partitioned based on thread identity or a group of thread identities. Thus the physical implementation can balance space versus performance concerns. In addition, it is submitted that it is within the knowledge of one skilled in the art to understand that the S-FIFO can also be implemented in an architecture that includes a read-write cache rather than separate read and write caches.
[0136] FIG. 7 illustrates a method of evicting entries, according to an embodiment. In one example, system 100 and system 300 may be used to demonstrate method 700 . It is to be appreciated that operations in method 700 may be performed in a different order than shown, and method 700 may not include all operations shown. For ease of discussion, and without limitation, method 700 will be described in terms of elements shown in FIG. 1 and FIG. 3 .
[0137] Method 700 depicts the flow of operations when evictions from a queue such as a First In First Out (FIFO) instead of a pool occur. Evictions can occur, for example, when the number of entries in the FIFO exceeds the size of the FIFO and the entry at the head of the FIFO is popped off the FIFO, or when a release marker is added to the tail of the FIFO and triggers prior write evictions. Method 700 includes operations at a L1 FIFO and L2 FIFO (not shown), for example.
[0138] Method 700 begins at step 710 and proceeds to step 715 .
[0139] At step 715 , method 700 proceeds to step 720 to depict L1 FIFO eviction operations.
[0140] At step 720 , method 700 determines whether L1 FIFO evicts a store entry or a release marker entry.
[0141] When a release marker is present in L1 FIFO and no prior writes exist ahead of the release marker entry, method 700 evicts a release marker entry and proceeds to step 725 .
[0142] At step 725 , the release marker is evicted from the head of L1 FIFO to the tail of L2 FIFO. The addition of the release marker triggers evictions of any prior store entries from L2 FIFO until the release marker itself is evicted from the head of L2 FIFO. When a L2 cache 340 (and hence L2 FIFO) is not present, the release marker is evicted from L1 FIFO, and an acknowledgement is sent to the originating thread that the release is complete.
[0143] Method 700 proceeds to step 745 .
[0144] At step 720 , if a release marker is present in L1 FIFO, the prior store entries in L1 FIFO ahead of the release marker are evicted in turn, to a L2 FIFO, and corresponding data in wL1 320 a are correspondingly evicted to wL2 340 . The prior store entries are evicted in the order of placement in L1 FIFO. Thus, the written data is guaranteed to be at the next level of the hierarchy by the time the release marker is evicted.
[0145] At step 720 , if L1 FIFO evicts a store entry, method 700 proceeds to step 730 .
[0146] At step 730 , method 700 determines if the corresponding data exists in the wL1 320 a . When the corresponding data does not exist, method 700 proceeds to step 735 . At step 735 , a cache replacement policy as is well known in the art, may be enforced and previously evicted the data from wL1 320 a ; the store entry at the head of L1 FIFO is evicted to the tail of L2 FIFO. Thus, embodiments support early evictions from the memory hierarchy.
[0147] Method 700 proceeds to step 745 .
[0148] At step 730 , if the corresponding data does exist in the wL1 320 a , method 700 proceeds to step 740 .
[0149] At step 740 , the store entry at the head of L1 FIFO is evicted to the tail of L2 FIFO. In addition, the corresponding data in wL1 320 a is evicted to wL2 340 .
[0150] When a L2 cache hierarchy is not present (not shown), embodiments include the following: evicting the prior store entry from the head of L1 FIFO; evicting data, when present, from the wL1 320 a associated with the evicted prior store entry to main memory; when the evicted prior store entry is associated with a StRel release synchronization event, signaling completion of release to the originating.
[0151] When a L2 cache hierarchy is present and the L2 cache hierarchy is an ordering point (not shown), embodiments further include the following: evicting the prior store entry from L1 FIFO; evicting data, when present, from the wL1 320 a associated with the evicted prior store entry to the ordering point; when the evicted prior store entry is associated with a StRel release synchronization event, signaling completion of release to the originating thread. Thus, a StRel can complete at an ordering point other than main memory, and local synchronization is possible (e.g., receipt of a LdAcq can complete at wL2 340 without having to access main memory 150 ). Note that main memory can also be an ordering point and would be a global ordering point.
[0152] Method 700 proceeds to step 745 .
[0153] At step 715 , method 700 proceeds to step 745 to depict L2 FIFO eviction operations.
[0154] At step 745 , method 700 determines whether L2 FIFO evicts a store entry or a release marker entry. Evictions may occur when a release marker entry is added to the tail of L2 FIFO that triggers evictions, or when the number of L2 FIFO entries exceeds a configurable threshold, for example. If L2 FIFO determines to evict a release marker entry, method 700 proceeds to step 750 .
[0155] At step 750 , the release marker is evicted from L2 FIFO. In addition, method 700 transmits an acknowledgment to the originating thread or original requester, CU 310 a , that the release event is complete. The release completion provides assurance that safe forward progress is possible beyond the release synchronization event.
[0156] Note that for a StRel release synchronization event, CU 310 a does not need to wait for the acknowledgement, but rather CU 310 a can continue processing other memory events until executing the next LdAcq. But, for barrier and fence release synchronization events, CU 310 a waits until a corresponding acknowledgement is received. Further, additional embodiments enable unsynchronized stores, if allowed by the memory model. These unsynchronized stores would not generate a store entry in L1 FIFO, rather, corresponding data could be written to wL1 320 a . Thus, unsynchronized stores would not load pool components with unnecessary operations.
[0157] The method proceeds to step 765 .
[0158] At step 745 , if L2 FIFO determines to evict a store entry, method 700 proceeds to step 755 .
[0159] At step 755 , method 700 determines if the corresponding data exists in wL2 340 . If the corresponding data does not exist, (e.g., due to a cache replacement policy enforcement) the store entry is evicted from the head of L2 FIFO and method 700 proceeds to step 765 .
[0160] At step 755 , when the corresponding data does exist, method 700 proceeds to step 760 .
[0161] At step 760 , the store entry is evicted from the head of L2 FIFO. In addition, the corresponding data in wL2 340 is evicted to main memory 150 . Further, if the data was from a store event portion of a StRel, method 700 signals completion of release to the originating thread.
[0162] Embodiments invalidate the data in rL1 caches 370 a and 370 b associated with the corresponding address. The invalidations may be completed by broadcasting invalidation messages to the L1 read-only caches, rL1 cache 370 a and rL1 370 b , to ensure release consistency. The invalidations are not critical to performance as the invalidations simply delay release synchronization completions and are bound based on the number of entries in L2 FIFO when a release synchronization event occurs. Note that write evictions and load requests do not stall waiting for invalidations. In addition, the data in rL1 370 a and rL1 370 b can be invalidated with a flash clear, e.g., when a LdAcq is received, all blocks in the cache are invalidated. The flash clear does not need to be associated with the corresponding address.
[0163] Method 700 proceeds to step 765 .
[0164] Logically, L1 FIFO and L2 FIFO may be implemented per thread identity or group of threads (e.g., wavefront identity).
[0165] In another embodiment, a pool of entries can be implemented with a Bloom-filter with a set of entries. A Bloom filter is an inexact representation of a set of elements. Bloom filters are implemented with an array of bits, and that array is indexed through two or more hash functions. To insert an element in the Bloom filter, the element is hashed and corresponding bits are set. To test membership, the element is hashed and corresponding bits are checked. If all bits are set (e.g., to “1”), the element may be in the set. If any one of the bits is cleared (e.g., to “0”), the element is not in the set. Unlike a mathematical set, Bloom filters have no remove function (though a variant called a counting bloom filter does). A signature is a representation of a set of elements. The pool can be implemented with a Bloom filter, an exact list (and/or array), or a FIFO, for example.
[0166] In summary, a prior store event is guaranteed to be ordered in the memory hierarchy whenever the store event has been evicted from a pool, dequeued from a FIFO, or tested for membership in a set using a Bloom-filter.
[0167] Various aspects of the disclosure can be implemented by software, firmware, hardware, or a combination thereof. FIG. 8 illustrates an example computer system 800 in which some embodiments, or portions thereof, can be implemented as computer-readable code. For example, the methods 400 - 700 , of FIGS. 4 through 7 can be implemented in system 800 . Various embodiments are described in terms of the example computer system 800 . After reading this description, it will become apparent to a person skilled in the relevant art how to implement the embodiments using other computer systems and/or computer architectures.
[0168] Computer system 800 includes one or more processors, such as processor 804 . Processor 804 can be a special purpose or a general purpose processor. Examples of processor 804 are CPU 110 and GPU 130 of FIG. 1 , or a GPGPU, or APU as described earlier. Processor 804 is connected to a communication infrastructure 806 (for example, a bus or network) such as bus 140 of FIG. 1 .
[0169] Computer system 800 also includes a main memory 808 , such as random access memory (RAM) such as main memory 150 of FIG. 1 , and may also include a secondary memory 810 . Secondary memory 810 may include, for example, a hard disk drive 812 , a removable storage drive 814 , and/or a memory stick. Removable storage drive 814 may comprise a floppy disk drive, a magnetic tape drive, an optical disk drive, a flash memory, or the like. The removable storage drive 814 reads from and/or writes to a removable storage unit 818 in a well-known manner. Removable storage unit 818 may comprise a floppy disk, magnetic tape, optical disk, etc. that is read by and written to by removable storage drive 814 . As will be appreciated by persons skilled in the relevant art(s), removable storage unit 818 includes a computer usable storage medium having stored therein computer software and/or data.
[0170] In alternative implementations, secondary memory 810 may include other similar means for allowing computer programs or other instructions to be loaded into computer system 800 . Such means may include, for example, a removable storage unit 822 and an interface 820 . Examples of such means may include a program cartridge and cartridge interface (such as that found in video game devices), a removable memory chip (such as an EPROM, or PROM) and associated socket, and other removable storage units 822 and interfaces 820 that allow software and data to be transferred from the removable storage unit 822 to computer system 800 .
[0171] Computer system 800 may also include a communications interface 824 . Communications interface 824 allows software and data to be transferred between computer system 800 and external devices. Communications interface 824 may include a modem, a network interface (such as an Ethernet card), a communications port, a PCMCIA slot and card, or the like. Software and data transferred via communications interface 824 are in the form of signals that may be electronic, electromagnetic, optical, or other signals capable of being received by communications interface 824 . These signals are provided to communications interface 824 via a communications path 826 . Communications path 826 carries signals and may be implemented using wire or cable, fiber optics, a phone line, a cellular phone link, an RF link or other communications channels.
[0172] In this document, the terms “computer program medium” and “computer usable medium” are used to generally refer to media such as removable storage unit 818 , removable storage unit 822 , and a hard disk installed in hard disk drive 812 . Signals carried over communications path 826 can also embody the logic described herein. Computer program medium and computer usable medium can also refer to memories, such as main memory 808 and secondary memory 810 , which can be memory semiconductors (e.g. DRAMs, etc.). These computer program products are means for providing software to computer system 800 .
[0173] Computer programs (also called computer control logic) are stored in main memory 808 and/or secondary memory 810 . Computer programs may also be received via communications interface 824 . Such computer programs, when executed, enable computer system 800 to implement the embodiments as discussed herein. In particular, the computer programs, when executed, enable processor 804 to implement the disclosed processes, such as the steps in the methods 400 - 700 of FIGS. 4-7 as discussed above. Accordingly, such computer programs represent controllers of the computer system 800 . Where the embodiments are implemented using software, the software may be stored in a computer program product and loaded into computer system 800 using removable storage drive 814 , interface 820 , hard drive 812 or communications interface 827 . This can be accomplished, for example, through the use of general-programming languages (such as C or C++). The computer program code can be disposed in any known computer-readable medium including semiconductor, magnetic disk, or optical disk (such as, CD-ROM, DVD-ROM). As such, the code can be transmitted over communication networks including the Internet and internets. It is understood that the functions accomplished and/or structure provided by the systems and techniques described above can be represented in a core (such as a processing-unit core) that is embodied in program code and may be transformed to hardware as part of the production of integrated circuits. This can be accomplished, for example, through the use of hardware-description languages (HDL) including Verilog HDL, VHDL, Altera HDL (AHDL) and so on, or other available programming and/or schematic-capture tools (such as, circuit-capture tools).
[0174] Embodiments are also directed to computer program products comprising software stored on any computer useable medium. Such software, when executed in one or more data processing device, causes a data processing device(s) to operate as described herein. Embodiments employ any computer useable or readable medium, known now or in the future. Examples of computer useable mediums include, but are not limited to, primary storage devices (e.g., any type of random access memory), secondary storage devices (e.g., hard drives, floppy disks, CD ROMS, ZIP disks, tapes, magnetic storage devices, optical storage devices, MEMS, nanotechnological storage device, etc.), and communication mediums (e.g., wired and wireless communications networks, local area networks, wide area networks, intranets, etc.).
[0175] It is to be appreciated that the Detailed Description section, and not the Summary and Abstract sections, is intended to be used to interpret the claims. The Summary and Abstract sections may set forth one or more but not all exemplary embodiments as contemplated by the inventor(s), and thus, are not intended to limit the disclosure and the appended claims in any way.
[0176] The disclosure has been described above with the aid of functional building blocks illustrating the implementation of specified functions and relationships thereof. The boundaries of these functional building blocks have been arbitrarily defined herein for the convenience of the description. Alternate boundaries can be defined so long as the specified functions and relationships thereof are appropriately performed.
[0177] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments that others can, by applying knowledge within the skill of the art, readily modify and/or adapt for various applications such specific embodiments, without undue experimentation, without departing from the general concept of the present disclosure. Therefore, such adaptations and modifications are intended to be within the meaning and range of equivalents of the disclosed embodiments, based on the teaching and guidance presented herein. It is to be understood that the phraseology or terminology herein is for the purpose of description and not of limitation, such that the terminology or phraseology of the present specification is to be interpreted by the skilled artisan in light of the teachings and guidance.
[0178] The breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents. | A method, computer program product, and system is described that enforces a release consistency with special accesses sequentially consistent (RCsc) memory model and executes release synchronization instructions such as a StRel event without tracking an outstanding store event through a memory hierarchy, while efficiently using bandwidth resources. What is also described is the decoupling of a store event from an ordering of the store event with respect to a RCsc memory model. The description also includes a set of hierarchical read-only cache and write-only combining buffers that coalesce stores from different parts of the system. In addition, a pool component maintains partial order of received store events and release synchronization events to avoid content addressable memory (CAM) structures, full cache flushes, as well as direct write-throughs to memory. The approach improves the performance of both global and local synchronization events and reduces overhead in maintaining write-only combining buffers. | 8 |
This application is a division of application Ser. No. 08/688,888 filed Jul. 31, 1996, now U.S. Pat. No. 5,693,420.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a thermally fusible composite fiber, and to non-woven fabric made of such a fiber.
2. Description of the Prior Art
A low-density non-woven fabric of a METSUKE (weight per unit area) between approximately 10 and approximately 45 g/m 2 is used as the surface material for paper diapers, sanitary napkins, and the like. As the uses of non-woven fabrics have become diversified, property requirements for non-woven fabrics have become more strict, and there has been demand for non-woven fabrics which maintain high strength at a minimum weight while retaining a soft texture. In the context of such a recent situation, products such as pants-type diapers are required to have a certain strength, and this is accomplished by heat-sealing non-woven fabrics with each other. For this reason, a non-woven fabric having excellent heat-sealing properties is demanded.
In order to satisfy such a demand, it is necessary that the non-woven fabric be constituted of fine, thermally fusible composite fibers, and that the low-melting component contributing to the thermal fusion of thermally fusible composite fibers have sufficient adhesive strength as well as flexibility.
Examples of thermally fusible composite fibers include the combinations of polypropylene and polyethylene, polyethylene terephthalate and polyethylene, and polyethylene terephthalate and poly (ethylene terephthalate)-co-(ethylene isophthalate). The polyethylene materials include high-density polyethylene, low-density polyethylene, and linear low-density polyethylene.
However, when low-density polyethylene or linear low-density polyethylene is used as the low-melting component of the thermally fusible fibers, the fibers may become adhered to one another at a low temperature, but are easily peeled apart. Also, although the resultant non-woven fabric has a soft feel, it has low strength, low rigidity due to low density, and a sticky feel. For example, Japanese Patent Application Laid-Open No. 63-92722 discloses a. fine thermally fusible composite fiber using linear low-density polyethylene having a low rigidity as the low-melting component, as well as a thermally fusible non-woven fabric comprising such a fiber. However, this fabric has poor heat-sealing properties and a low strength, and does not satisfy the requirements of the non-woven fabric achieving the object of the present invention.
On the other hand, non-woven fabric made of thermally fusible composite fibers in which high-density polyethylene is used as the low-melting component has higher density and rigidity, higher strength, and good heat-sealing properties as compared to non-woven fabrics made of low-density polyethylene and linear low-density polyethylene. However, since the high-density polyethylene used as the low-melting component has a high melting point, the processing temperature must be elevated in order to achieve sufficient non-woven strength and heat-sealing properties. This is disadvantageous in that the resultant non-woven fabric has a stiff feel. Furthermore, although lower non-woven processing temperatures are desirable from the point of view of energy costs, sufficient strength cannot be achieved unless the processing temperature is sufficiently high.
In order to solve such problems, a thermally fusible composite fiber disclosed in Japanese Patent Application Laid-Open No. 2-251612 has as its high-melting component polypropylene or polyester, and as its low-melting component high-density polyethylene, which has many methyl branches in its molecular chain and a relatively low melting point. However, increasing the number of methyl branches in polyethylene generally lowers the density, and increasing the Q value (weight average molecular weight Mw/number average molecular weight Mn) increases the unevenness of the polymer. Both of these effects lower the tensile strength of the low-melting component, lower the adhesive strength of the low-melting component at points where fibers intersect one another, and result in insufficient strength of the fabric itself and of heat sealing.
SUMMARY OF THE INVENTION
It is the object of the present invention to solve the above-mentioned disadvantages in the prior art, and to provide a thermally fusible composite fiber having high strength, having soft feel, and achieving a high heat-sealing strength within a short heat-sealing time.
The inventors of the present invention conducted repeated studies to solve the above problems, and found that a non-woven fabric having a high heat-sealing strength as well as a high fabric strength and a soft feel can be produced by processing into a non-woven fabric a thermally fusible composite fiber having as its low-melting component specific polyethylene. As the result, the inventors found that the desired object was achieved, and completed the present invention.
According to a first aspect of the present invention, there is provided a side-by-side type or sheath-and-core type thermally fusible composite fiber comprising a first component made of polyethylene and a second component made of polyester, said polyethylene occupying continuously at least a portion of the surface of the fiber in the length direction, wherein said polyethylene is a copolymer having 1.6/1,000 C or more methyl branches in its molecular chains, a density from 0.940 to 0.965 g/cm 3 , and a Q value (weight average molecular weight Mw/number average molecular weight Mn) of 4.8 or less.
According to a second aspect of the present invention, there is provided a thermally fusible composite fiber according to the first aspect, wherein the number of methyl branches in the first component is 5.0/1,000 C or more.
According to a third aspect of the present invention, there is provided a non-woven fabric containing at least 20 percent of side-by-side type or sheath-and-core type thermally fusible composite fibers each comprising a first component made of polyethylene and a second component made of polyester, said polyethylene occupying continuously at least a portion of the surface of the fibers in the length direction, wherein said polyethylene is a copolymer having 1.6/1,000 C or more methyl branches in its molecular chains, a density from 0.940 to 0.965 g/cm 3 , and a Q value (weight average molecular weight Mw/number average molecular weight Mn) of 4.8 or less, and wherein the intersections of the fibers are thermally fused by polyethylene which is the first component of said thermally fusible composite fibers.
According to a fourth aspect of the present invention, there is provided a non-woven fabric according to the third aspect, wherein the number of methyl branches in the molecular chains of the first component is 5.0/1,000 C or more.
According to a fifth aspect of the present invention, there is provided a formed article produced using thermally fusible composite fibers according to the first or second aspect.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present invention will next be described in detail.
The polyester resin used in the high-melting component of the thermally fusible composite fiber of the present invention may be any thermoplastic polyester generally used as the material of fibers. For example, the polyester resin may be polyethylene terephthalate, as well as copolymers such as poly (ethylene terephthalate)-co-(ethylene isophthalate)!, preferably having a melting point between 250° and 260° C. and an inherent viscosity between 0.5 and 1.2 (in the mixed solvent of 60% by weight of phenol and 40% by weight of tetrachloroethane at 30° C.).
Polyethylene used in the present invention must be adjusted so as to have a density from 0.940 to 0.965 g/cm 3 . Non-woven fabric made of thermally fusible composite fibers having a density exceeding 0.965 g/cm 3 tends to have a stiff feel, because of a high processing temperature necessary to achieve high strength. In heat sealing, the sheath component flows easily due to a high stiffness of the low-melting component. Also, since a long time is required before the sheath component starts flowing, the heat sealing temperature must be elevated, or the heat sealing time must be adjusted. On the other hand, although non-woven fabric made of thermally fusible composite fibers having a density of less than 0.940 g/cm 3 has a soft feel, high fabric strength and high heat sealing strength cannot be achieved because of a low stiffness of the low-melting component, and therefore, such polyethylene cannot be used. Consequently, from both aspects of strength and feel, the density of the polyethylene material is preferably between 0.940 and 0.965 g/cm 3 , and most preferably between 0.941 and 0.955 g/cm 3 . The term "density" used herein is a value obtained by preparing a test piece using compression molding in accordance with JIS K-6758, and subsequently measuring using the density grade tube method in accordance with JIS K-7112.
The polyethylene resin used in the present invention should have a Q value of 4.8 or less, and more preferably 4.0 or less. If the Q value exceeds 4.8, the tensile strength of the woven fabric lowers, the adhesive strength at the point where fibers formed of the high-melting component intersect and adhere to one another by the fusion of the low-melting component becomes insufficient, and non-woven fabric with high strength cannot be produced when the non-woven fabric is produced by the heat treatment and adhesion of the fibers, because of the broad molecular-weight distribution of the polyethylene forming the low-melting component in the fibers. Although there is no lower limit of the Q value, the lowest value which can be attained in the actual production process is considered to be approximately 3. Heat sealing strength corresponding to the tensile strength is achieved if other conditions are identical.
The Q value used herein is the ratio of the weight average molecular weight to the number average molecular weight, as measured using gel permeation chromatography in an o-dichlorobenzene solution at 140° C.
The number of methyl branches in the molecule chains of the polyethylene resin used in the present invention is preferably 1.6/1,000 C or more, and more preferably 5.0/1,000 C or more. When the density is 0.940, the upper limit of the number of methyl branches is estimated to be approximately 10. The methyl branch used herein is a methyl group branched directly from the main chain of polyethylene, and methyl groups not bonded directly to the main chain, such as the end methyl group of an ethyl branch, are not included. The number of methyl branches is the number of methyl groups directly bonded to the main chain of polyethylene per 1,000 carbon atoms in the main chain. Such methyl groups can be determined quantitatively from the nuclear magnetic resonance spectra of carbon atoms having a mass number of 13.
As seen in linear low-density polyethylene, density decreases as the number of not only methyl branches but also any other branches increases in co-polymerized polyethylene. For this reason, since the low-melting components start flowing at a low temperature, the temperature for processing non-woven fabric can be lowered. However, since ethyl branches or branches larger than ethyl branches cause significant lowering of density, a large number of such branches cannot be introduced. Therefore, methyl branches are most preferred for minimizing lowering of density and for introducing a large number of branches. It was thus found that increasing the number of methyl branches is effective for minimizing decrease in tensile strength due to lowering of density, for improving melt-flow properties at low temperatures, and for producing polyethylene with good heat-sealing properties. However, longer branches may be contained if the density is within the range of the present invention.
By heat sealing the thermally fusible composite fibers of the present invention, which has such specific polyethylene as the low-melting component, non-woven fabrics having high heat-sealing strength are produced even at relatively low temperatures.
Co-polymerized polyethylene of the present invention, which meets the above requirements, is produced by co-polymerizing ethylene with a small amount of propylene in the presence of catalysts such as Ziegler-Natta, chromium oxide, molybdenum oxide, and Kaminski-type catalysts using conventional manufacturing processes such as the solution method, the gas-phase method, or the high-temperature high-pressure ionic polymerization method.
Co-monomers used here are not limited to propylene, but may be 1-olefins having 4 or more carbon atoms, which produce a branch longer than a methyl branch. For example, butene-1, pentene-1, hexene-1, 4-methyl pentene-1, heptene-1, octene-1, nonene-1, and decene-1 may be used singly or in combination. Other α-olefins may also be used if they produce a polyethylene having a density and Q value within the range of the present invention, and two or more α-olefins may be used to produce a terpolymer and so on.
Although the melt-flow rate (MFR; 190° C., ASTM D1238(E)) of the polyethylene used in the present invention may be in the range between 5 and 45, the preferable range is between 8 and 28 because of the ease of spinning. For preventing deterioration of the polymer during spinning and for preventing the discoloration of non-woven fabrics, additives used in ordinary polyolefins, such as antioxidants, light stabilizers, and heat stabilizers, as well as colorants, lubricants, anti-static agents, and delustrants may be combined as required.
The thermally fusible composite fibers are spun into side-by-side type yarns, in which polyester, which is the high-melting component; and polyethylene, which is the low-melting component; are arranged in side-by-side type or into sheath-and-core type yarns in which the polyethylene acts as a sheath. The sheath-and-core type yarns may be concentric or eccentric.
The ratio of the high-melting component to the low-melting component is preferably from 30/70 to 70/30 by weight, and more preferably from 40/60 to 60/40 by weight. Other spinning and drawing conditions may be the same as those for composite fibers consisting of ordinary polyester and polyethylene. Although there is no limitation in the single fiber fineness and the number of crimps of the fibers, for balancing fabric strength and feel, the single fiber fineness is preferably from 0.5 to 6.0 denier, more preferably from 1.0 to 3.0 denier; and the number of crimps is preferably from 5 to 30 crimps per inch, more preferably from 10 to 20 crimps per inch.
The non-woven fabric of the present invention is produced from the thermally fusible composite fibers of the present invention alone, or from mixed fibers containing 20 percent by weight or more, preferably 50 percent by weight or more, the thermally fusible composite fibers of the present invention; by webbing such fibers using well-known methods such as carding, air lay, dry pulp, wet paper making, and tow opening methods; and heat-treating the webs for thermally adhering the intersections of the thermally fusible composite fibers.
The methods of heat treatment include methods using a drier such as a hot-air drier, a suction band drier, or a Yankee drier; as well as methods using a roll such as a flat calender roll or an emboss roll.
There is no limitation in the METSUKE of the non-woven fabric, and it can be changed to meet the requirements of applications. When the non-woven fabric is used for the surface material of paper diapers or sanitary napkins, the METSUKE is preferably from 8 to 50 g/m 2 , and more preferably from 10 to 30 g/m 2 .
Other fibers which can be used in combination with the thermally fusible composite fibers may be any fibers so long as those fibers are not affected by heat treatment, and they do not affect the object of the present invention. Examples include synthetic fibers such as polyester, polyamide, polypropylene, and polyethylene; natural fibers such as cotton and wool, and fibers such as rayon.
Since the low-melting component of the thermally fusible composite fibers acts as a binder in the non-woven fabric of the present invention, if the content of the thermally fusible composite fibers is less than 20 percent, the number of adhesion points at the intersections of the fibers decreases, and high fabric strength cannot be achieved.
Although the thermally fusible composite fibers and the non-woven fabric made of such composite fibers are suitably used as the surface material of paper diapers, sanitary napkins and the like, these fibers and fabrics may also be applied widely to medical uses such as surgical gowns; civil-engineering materials such as drainage or soil improving materials; industrial materials such as oil absorbers; and household materials such as tray mats for packaging fresh foods including fish and meat.
Furthermore, formed products such as cartridge filters may be produced by thermally fusing the composite fibers of the present invention at higher fiber density than in non-woven fabrics.
The present invention will be described in further detail by referring to Examples and Comparative Examples. Methods for evaluating properties used in each example are as follows: Non-woven fabric strength:
The material short fibers were processed into a web having a METSUKE of about 20 g/cm 2 using a miniature carding machine, and passed between metal rolls (upper: emboss roll with 25% boss area, lower: flat roll) having a diameter of 165 mm and keeping a temperature between 120 and 132° C. into a non-woven fabric under the conditions of a linear pressure of 20 kg/cm and a speed of 6 m/min. From the resulting non-woven fabric, test pieces each having a width of 5 cm in the direction of machine movement (MD) and in the direction perpendicular to the machine flow (CD) were prepared, and the tensile strength of each test piece was measured using a tensile tester with a clamp distance of 10 cm and at a pulling speed of 10 cm/min. Heat-sealing properties:
Two test pieces, each having a width of 2.5 cm, were cut from the non-woven fabric used for the above tensile test, and an area of a test piece 1 cm from the end was overlaid on the same area of another test piece, and compressed at a pressure of 3 kg/cm 2 and a temperature between 130° and 145° C. for 0.1 second so as to form a composite piece. The peeling strength was measured using a tensile tester under the conditions of a clamp distance of 10 cm and a pulling speed of 10 cm/min. Feel of non-woven fabrics:
Organoleptic tests were performed by five panel members. When all panel members considered that there was no stiff feel due to wrinkling or the like, and that the sample was soft, the sample was evaluated as good (◯); when three or more panel members considered as above, the sample was evaluated as (Δ); and when three or more panel members considered that the sample has stiff feel due to wrinkling or the like, or the sample lacked in soft feel, the sample was evaluated as poor (X).
EXAMPLES 1-4 AND COMPARATIVE EXAMPLES 1-3
Polyester (polyethylene terephthalate; PET, inherent viscosity (measured in accordance with JIS Z-8808): 0.65) as the high-melting component was extruded at a temperature of 300° C., and high-density polyethylene (all cases except Comparative Example 3) or low-density polyethylene (Comparative Example 3) listed in Table 1 as the low-melting component was extruded at a temperature of 200° C., at a rate of 282 g of total resins per minute from a sheath-and-core type die having 350 holes, each having a diameter of 0.6 mm, so as to form sheath-and-core type composite fiber, the core of which is polyester and the sheath of which is polyethylene, in the polyester/polyethylene ratio of 6:4 (by weight) and having a single fiber denier number of 6.7 d/f. The yarn was drawn to 3.3 times its original length at 90° C., crimped, heat-treated at 80° C. to control shrinkage, and cut into thermally fusible composite fiber staples having a cut length of 51 mm.
The resultant thermally fusible composite fiber staples were passed through a carding machine, and the web produced was processed into a non-woven fabric using emboss/flat rolls at 120°-132° C.
As Table 2 shows, the non-woven fabrics produced from composite fibers of Examples 1-4 according to the present invention had high fabric strength in both lengthwise (MD) and transverse (CD) directions, high heat-sealing strength, and good feel. However, the non-woven fabrics of Comparative Examples 1 and 3 had low fabric strength, and although the non-woven fabric of Comparative Example 2 had high fabric strength, it had poor feel and its processing temperature was high. Regarding heat-sealing strength, as Table 3 shows, the non-woven fabric of Comparative Example 1 had high heat-sealing strength, but its processing temperature was high; that of Comparative Example 2 had low fabric strength and its processing temperature was high; and that of Comparative Example 3 could be processed at a low temperature, but its strength was low. Example 5 and Comparative Examples 4 and 5
Polyester (polyethylene terephthalate; PET, inherent viscosity: 0.65) as the high-melting component at a extrusion temperature of 300° C., and high-density polyethylene or low-density polyethylene listed in Table 1 as the low-melting component at a extrusion temperature of 200° C., were co-extruded at a rate of 282 g of total resins per minute from a sheath-and-core type die having 350 holes, each having a diameter of 0.6 mm, so as to form sheath-and-core type composite fiber, the core of which is polyester and the sheath of which is polyethylene, in the polyester/polyethylene ratio of 6:4 (by weight) and having a single fiber denier number of 6.7 d/f. The yarn was drawn to 3.3 times its original length at 90° C., crimped, heat-treated at 80° C. to control shrinkage, and cut into thermally fusible composite fiber staples having a cut length of 51 mm.
The resultant thermally fusible composite fiber staples (15-25% by weight) were optionally mixed with polyethylene terephthalate fiber staples of a single fiber denier number of 6 d/f and a fiber length of 51 mm (75-85% by weight), and the mixed staples were passed through a carding machine, and the web produced was heat-treated using emboss/flat rolls at 124°-132° C. to form a non-woven fabric in which the intersections of thermally fusible fibers had been fused.
As Tables 2 and 3 show, thermally fused non-woven fabrics containing 20 percent or more by weight of the composite fibers of the present invention (Examples 5 and 6) had high fabric strength, high heat-sealing strength, and good feel. However, the non-woven fabric of Comparative Example 4 and that of Comparative Example 5 containing not more than 20 percent composite fibers of the present invention, had low strength in the transverse direction (CD).
TABLE 1______________________________________Properties of fibers Low-melting componentHigh- MFR Den-melting Type g/10 Me branch/ sity Q valuecomponent *1 min 1000 C g/cm.sup.3 Mw/Mn______________________________________Example 1 PET A1 16 6.6 0.945 4.2Example 2 PET A2 15 2.5 0.955 3.5Example 3 PET A3 18 3.2 0.951 3.9Example 4 PET A4 13 7.1 0.941 4.1Comp.Ex.1 PET a1 14 1.0 0.955 5.2Comp.Ex.2 PET a2 16 <0.3 0.971 3.5Comp.Ex.3 PET b1 19 12.7 0.920 6.5______________________________________ *1: Type A: Highdensity polyethylene according to the present invention (suffixes indicate identification numbers). a: Highdensity polyethylene not according to the present invention (suffixes indicate identification numbers). b: Lowdensity polyethylene
TABLE 2______________________________________ PropertiesConditions of production FabricCon- process MET- strengthtent Other temp. SUKE kg/5 cm% Type fibers °C. g/m.sup.2 MD CD Feel______________________________________Example 1 100 A1 -- 124 21 6.1 1.3 ∘Example 2 100 A2 -- 128 19 7.7 1.8 ΔExample 3 100 A3 -- 128 21 7.5 1.6 ∘Example 4 100 A4 -- 124 22 5.9 1.2 ∘Comp. Ex. 1 100 a1 -- 128 20 5.9 0.8 ΔComp. Ex. 2 100 a2 -- 132 22 8.2 1.8 xComp. Ex. 3 100 b1 -- 120 19 3.9 0.5 ∘Example 5 25 A1 PET 124 22 2.3 0.5 ΔExample 6 25 A4 PET 124 21 2.5 0.7 ΔComp. Ex. 4 25 a2 PET 132 23 2.8 0.8 xComp. Ex. 5 15 A1 PET 124 20 1.7 0.2 Δ______________________________________
TABLE 3______________________________________ Heat-sealing Heat-sealing Content Other temperature strength % Type fibers °C. kg/25 mm______________________________________Example 1 100 A1 -- 135 0.580 140 1.250 145 1.900Example 2 100 A2 -- 135 0.300 140 0.739 145 1.155Example 3 100 A3 -- 135 0.516 140 1.023 145 1.873Example 4 100 A4 -- 135 0.623 140 1.677 145 1.988Comparative 100 a1 -- 135 0.251Example 1 140 0.622 145 1.136Comparative 100 a2 -- 135 --Example 2 140 0.257 145 0.829Comparative 100 b1 -- 130 0.597Example 3 135 0.652 140 0.981Example 5 25 A1 PET 130 -- 135 0.226 140 0.597Example 6 25 A4 PET 130 -- 135 0.279 140 0.639Comparative 25 a2 PET 140 --Example 4 145 0.156 150 0.531Comparative 15 b1 PET 125 --Example 5 130 -- 135 0.348______________________________________
By the use of the thermally fusible composite fiber of the present invention using specific polyethylene as the low-melting component, a non-woven fabric having high strength, good heat-sealing properties, and soft feel was produced.
The thermally fusible composite fibers according to the present invention and non-woven fabrics made of such fibers may be used for hygienic materials which are the surface materials of paper diapers, sanitary napkins, and the like; as well as medical materials such as surgical gowns; civil-engineering materials such as draining or soil improving materials; industrial materials such as oil absorbers; and household materials such as tray mats for packaging fresh foods including fish and meat. | A non-woven fabric comprising thermally fusible composite fibers with shortened heat-sealing time and improved heat-sealing strength is provided. The non-woven fabric is produced using side-by-side type or sheath-and-core type thermally fusible composite fibers comprising a first component consisting of polyethylene and a second component consisting of polyester, said polyethylene occupying continuously at least a portion of the surface of the fiber in the length direction, wherein said polyethylene is a copolymer having 1.6/1,000 C or more methyl branches in its molecular chains, a density from 0.940 to 0.965 g/cm 3 , and a Q value (weight average molecular weight Mw/number average molecular weight Mn) of 4.8 or less. | 3 |
REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of application Ser. No. 09/306,925, filed May 7, 1999, which claims priority to provisional patent application Ser. No. 60/085,102, filed May 12, 1998, commonly owned with the instant application.
BACKGROUND TO THE INVENTION
[0002] This invention relates generally to self propelled devices for cleaning submerged surfaces such as found in swimming pools. More particularly, it relates to friction feet which support swimming pool cleaners relative to and engagable with a surface to be cleaned.
[0003] Mechanical pool cleaners which utilize the flow of water drawn through the cleaner by means of a connecting flexible suction hose in communication with a filtration system pump are well known. Such pool cleaners are termed suction cleaners. Some suction cleaners include devices to establish reciprocating, impulsive, and vibratory forces useful for providing the propulsive force to move the cleaner in a random manner across the surface to be cleaned.
[0004] In U.S. Pat. No. 3,803,658 to Raubenheimer, an apparatus is disclosed which uses a repetitive variation in the flow of fluid through the apparatus to submit various components to variable loads and thereby impart stepwise movement to the apparatus across the surface to be cleaned.
[0005] A suction cleaner described in U.S. Pat. No. 4,023,227 to Chauvier uses the oscillatory movement of a flapper valve located in the operating head of the cleaner to impart impulsive forces to the apparatus for the purpose of moving the apparatus along the surface to be cleaned. U.S. Pat. Nos. 4,133,068, and 4,208,752 to Hofmann also use an oscillatable valve located in the head of the cleaner to provide impulsive forces to the apparatus for the purpose of moving the apparatus along the surface to be cleaned.
[0006] U.S. Pat. Nos. 4,682,833 and 4,742,593 to Stoltz and Kallenbach, respectively, disclose the use of an expansible tubular diaphragm to achieve a pulsating flow of fluid through the cleaner assembly and resultant forces suitable for the displacement of a pool cleaning apparatus over a surface to be cleaned.
[0007] Other means to provide impulsive, vibratory forces to a pool cleaner device are disclosed in U.S. Pat. No. 4,807,318 to Kallenbach, U.S. Pat. Nos. 4,769,867 and 4,817,225 to Stoltz and U.S. Pat. No. 5,404,607 to Sebor.
[0008] U.S. Pat. No. 4,434,519 to Raubenheimer describes a suction cleaner having at least one friction support attached directly to the frame of the cleaner for engaging the submerged surface. The cleaner uses turbine means to impart reciprocating vibratory forces to the frame oblique to the submerged surface and alternately acting through the friction support in two opposed directions, the force in a first direction tending to lift the friction support from the surface and the force in the second direction tending to push the friction support back onto the surface, the resulting effect of said oblique forces and the bias caused by suction causing the apparatus to advance over the surface in a step by step manner. The friction support is a pivotally mounted foot projecting at an angle to the submerged surface and biased towards the vertical of said surface. Further improvements and a later embodiment of the aforementioned device were disclosed by Raubenheimer in U.S. Pat. No. 4,536,908.
[0009] U.S. Pat. No. 5,293,659 to Rief et al. discloses the use of a vibrator device and inclined bristle supports which work together to cause forward movement of the cleaner over the surface to be cleaned. Rief '659 discloses bristle supports inclined resilient supports. The term “resilient” is described as being the inherent characteristic of the support itself to bend. The bottom ends of the supports are offset from their corresponding top ends in a common direction.
SUMMARY OF THE INVENTION
[0010] In view of the foregoing background, it is therefore an object of the present invention to provide improved friction supports for incorporation into swimming pool devices which, in order to achieve forward motion, use the action of reciprocating vibratory forces and such friction supports in engagement with a submerged surface to be cleaned. In particular, it is an object of this invention to improve upon the stiff pivotally mounted friction supports known in the art by integrally forming the resilient biasing means with a stiff, support. This will reduce the number of components and simplify assembly and maintenance. A further object is to integrally form the pivot means or fulcrum with either the housing or the support itself. This will further reduce the number of components, simplify assembly and maintenance. It is yet another object to provide means which will enable oscillatory movement of a stiff or generally rigid support without the need for engagement of the support against a shaft or fulcrum. Yet another object is to use resilient membranes which are predisposed to deform in a desired manner to provide oscillatory movement of the free end of a support, regardless of whether or not the support is initially oriented at an angle to the surface to be cleaned. It is also contemplated that the system and method are useful in fluid environments other than swimming pools and spas. Further, the invention will be useful for incorporation with “pressure end” swimming pool cleaners which operate on the return flow of fluid from a pump, through a flexible hose connected to the cleaner and into the swimming pool.
[0011] According to the present invention, there is provided a device for cleaning surfaces submerged in a liquid. A swimming pool cleaner operable through a vibratory movement thereof is provided and comprises a housing, vibrating means carried by the housing for providing a vibratory movement thereto, a friction support carried by the housing at a first orientation thereto for operably engaging a surface to be cleaned, the friction support having a first end pivotally attached to the housing, and a second free end in frictional contact with the surface to be cleaned, and biasing means operable between the housing and the friction support for biasing the friction support toward the first orientation and limiting movement thereof, which movement displaces the free end and thus the support from the first orientation to a second orientation.
[0012] The cleaner is in communication with a suction pump and motor by means of a flexible elongated hose connected to a coupling located on top of a housing. The cleaner housing incorporates at least one suction chamber comprising an entrance end in proximity to the submerged surface to be cleaned and an exit end communicating with the coupling. A vibrator device is located within at least one suction chamber. At least one support is attached relative to the device for engaging the submerged surface to be cleaned. The support may be partly or wholly manufactured from a rubber-like friction material. Its free end may integrally incorporate or be capable of receiving an attachment incorporating a protuberance, shape, dimension or surface characteristic which will provide a frictional grip against the surface to be cleaned.
[0013] During operation, an inertial mass forming part of the cleaning device, energized by a vibratory device into vibratory or to-and-fro motion, acts through the friction supports to generate reciprocating forces oblique to the surface to be cleaned and in at least two opposed directions in turn, the force in an upwards direction tending to lift the support from the surface and the force in a downwards direction tending to push the friction support back onto the surface, the resultant of the downward force and the downward bias caused by suction, causing the apparatus to advance over the surface in a step by step manner.
[0014] All of the supports disclosed have the following common characteristic: Their free ends are all capable of oscillatory movement between two positions; typically a few millimeters.
[0015] First embodiments of substantially rigid, stiff friction supports (i.e. supports which do not bend and straighten along their length) are pivotally mounted to the cleaner device at an angle to the surface to be cleaned, such that, upon application of a downward force, the support will oscillate about an axis generally lateral to the downward force, the improvement being that means to return the friction support to the first position upon removal of the downward force are integrally formed with the friction support.
[0016] Second embodiments of friction supports are attached and oriented such that the point of contact by each support's free end against the surface to be cleaned is directly below the point of attachment of the support relative to the housing (i.e. the supports are not inclined), the shape of the support between the latter points designed such that, upon application of a downward force, at least a portion of the support will flex and thus produce a resultant force including a component capable of moving the cleaner device in a forward direction.
[0017] Yet other embodiments of friction supports have at least two points of attachment with respect to the housing such that lines drawn between the points of attachment of each support and the point of contact by each support's free end against the surface to be cleaned will not incline in a common direction.
BRIEF DESCRIPTION OF DRAWINGS
[0018] A preferred embodiment of the invention, as well as alternate embodiments are described by way of example with reference to the accompanying drawings in which:
[0019] [0019]FIG. 1 is a cross-section view of a pool cleaner illustrating one embodiment of friction supports of the present invention;
[0020] [0020]FIG. 2 is a bottom plan view of the pool cleaner of FIG. 1;
[0021] [0021]FIG. 3 is a partial enlarged, cross-section view of the friction support of FIG. 1;
[0022] [0022]FIG. 4 is a partial cross-section view of a second embodiment of the friction support of the present invention;
[0023] [0023]FIG. 5 is a partial perspective bottom view of the pool cleaner of FIG. 1;
[0024] FIGS. 6 A- 6 D are partial cross-section views of the friction support of FIG. 1, illustrating operation thereof;
[0025] [0025]FIGS. 7A and 7B are partial cross-section views of a third embodiment of a friction support illustrating operation thereof;
[0026] [0026]FIGS. 8A and 8B are partial cross-section views of a fourth embodiment of a friction support illustrating operation thereof;
[0027] [0027]FIGS. 9A and 9B are partial cross-section views of a fifth embodiment of a friction support illustrating operation thereof;
[0028] [0028]FIGS. 10A and 10B are partial cross-section views of a sixth embodiment of a friction support illustrating operation thereof;
[0029] [0029]FIG. 11 is a partial cross-section view of a seventh embodiment of the present invention;
[0030] [0030]FIGS. 12A and 12B are partial cross-section views of an eighth embodiment of a friction support illustrating operation thereof;
[0031] [0031]FIGS. 13A and 13B are partial cross-section views of a ninth embodiment of a friction support illustrating operation thereof;
[0032] [0032]FIGS. 14A and 14B are partial cross-section views of a tenth embodiment of a friction support illustrating operation thereof;
[0033] [0033]FIGS. 15A and 15B are partial cross-section views of an eleventh embodiment of a friction support illustrating operation thereof;
[0034] [0034]FIGS. 16A and 16B are partial cross-section views of a twelfth embodiment of a friction support illustrating operation thereof;
[0035] [0035]FIGS. 17A and 17B are partial cross-section views of a thirteenth embodiment of a friction support illustrating operation thereof; and
[0036] FIGS. 18 - 29 are partial cross-section views of yet other embodiments of a friction supports of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.
[0038] [0038]FIGS. 1 and 2 show a device 1 for cleaning a surface 2 submerged in a liquid. The cleaner 1 is in communication with a remote suction pump and motor by means of a flexible elongated hose 3 connected to a coupling 4 located on top of a housing 5 . The cleaner housing 5 incorporates at least one suction chamber 6 comprising a fluid entrance end 7 in proximity to the submerged surface 2 to be cleaned and an exit end 8 communicating with the coupling 4 . A vibrator device 9 such as a flapper valve, turbine with weight, turbine with eccentrics or other vibrator device as described in the prior art is located within at least one suction chamber 6 . An outer housing 10 may be fitted to the main housing 5 . At least one support 11 is attached relative to the device 1 for engaging the submerged surface 2 to be cleaned.
[0039] The free end 11 . 2 of the rigid support 11 must be able to move a distance of a few millimeters between a first and a second position, and then spring back to the first position.
[0040] In preferred embodiments illustrated in FIGS. 3 and 4, the support is pivotally mounted at an angle to the surface 2 to be cleaned. FIG. 4 depicts a support 11 with a bore 11 . 5 into which a shaft 11 . 7 is inserted. FIG. 3 depicts a pivot member or fulcrum 11 . 6 integrally formed with the main housing 5 and a support 11 with a bore or cup 11 . 5 adapted to engage with the pivot member 11 . 6 . Rotation of the support 11 about a pivot axis enables oscillatory movement of the free end 11 . 2 of the support. The illustrated supports 11 may be partly or wholly manufactured from a rubber-like friction material and, in operation, are substantially rigid; i.e. do not bend and straighten along their length between the free end 11 . 2 and the opposing end proximate the pivot axis.
[0041] The preferred embodiments shown in FIGS. 3 and 4 are integrally formed with resilient biasing or spring means 11 . 4 to orient the rigid support 11 to a first position and to limit movement of the free end 11 . 2 of the support. This arrangement improves upon the prior art by eliminating the need for a separate orientation spring and stop. The embodiment in FIG. 3 further improves on the prior art because the pivot member 11 . 6 integrally formed with the main housing 5 eliminates the need for a separate shaft and means to position and attach such shaft to the housing 5 .
[0042] As illustrated by FIGS. 1 and 3, to simplify assembly of the device 1 and further reduce the number of separate parts required, support attachment means 11 . 1 may also be integrally formed with the support 11 , or both the support 11 and resilient biasing means 11 . 4 , to enable removable attachment of the support 11 , the main housing 5 and the outer housing 10 . Additionally as illustrated by FIGS. 1, 2 and 5 , the integrally formed supports, resilient biasing means 111 . 4 and attachment means form a membrane-like barrier between dirt-laden fluid flow 12 towards the chamber entrance end 7 and the end of the support proximate and including the pivot bore or cup 11 . 5 . This reduces the detrimental effect of dirt and grit upon the pivoting action of the supports 11 . A modified bore or cup 11 . 6 for engagement with a pivot member 11 . 6 is preferred over a completely round bore 11 . 5 because the modified bore or cup will be less prone to entrap dirt and thus hinder or prevent the support 11 from being able to pivot.
[0043] As depicted in FIG. 4, the free end 11 . 2 of a support 11 may integrally incorporate or be capable of receiving an attachment 11 . 3 incorporating a protuberance, shape, dimension or surface characteristic which will provide a frictional grip against the surface 2 to be cleaned.
[0044] [0044]FIGS. 6A, 6B, 6 C and 6 D illustrate the operation of a pivotable rigid support 11 .
[0045] In operation, the cleaning device 1 is energized by a vibratory device 9 into vibratory or to-and-fro motion. The vibrating mass acts through the rigid friction supports 11 to generate reciprocating forces oblique to the surface 2 to be cleaned and in at least two opposed directions in turn. FIG. 6A shows a support in a neutral position. This state will exist prior to the application of any force other than that applied by an inertial mass forming part of the cleaning device 1 ; i.e. prior to activation of the vibratory device by action of the fluid flow through the suction chamber 6 . A similar state will momentarily exist as the forces applied to the support 11 reciprocate between the downward and upward directions. In FIG. 6B, a force in a downwards direction 14 pushes the friction support 11 against the surface 2 . While the frictional grip of the free end 11 . 2 against the surface 2 maintains the position of the free end 11 . 2 relative to an imaginary point on the surface 2 marked “A”, the downwards force 14 causes the support to pivot which, in turn, causes the resilient biasing means 111 . 4 to deform and the housing to which the support 11 is attached to move a distance “e” in the direction of arrow 13 . Upon reciprocation of the force in the opposite, (upwards) direction, the support 11 will momentarily be lifted from the surface as shown in FIG. 6C. As this occurs, the resilient biasing means 11 . 4 will return the support to the neutral position. FIG. 6D shows, at a moment immediately prior to the re-commencement of the cycle just described, the support 11 re-engaged with the surface and the new position of the free end 11 . 2 of the support 11 relative to point “A” against the surface 2 . The free end 11 . 2 is shown to have moved a distance “e” in the direction of arrow 13 . This illustrates how the cleaner device 1 will, in response to vibration, advance over the surface 2 in a step by step manner.
[0046] [0046]FIG. 7A illustrates a rigid support 11 oriented at an angle to the surface 2 to be cleaned. An upper end 11 . 8 of the support 11 opposing the surface 2 contacting free end 11 . 2 , is shaped and resiliently positioned in slidable engagement with the housing 5 such that, upon application of downward force 14 , the upper end 11 . 8 will pivot against the housing 5 as shown in FIG. 7B. This embodiment eliminates the need for a pivot member 11 . 6 .
[0047] [0047]FIGS. 8A and 8B depict an improvement in which the housing 5 is shaped 5 . 1 to form a groove to receive and position the upper end 11 . 8 of a rigid support 11 .
[0048] [0048]FIGS. 9A and 9B depicts an alternative embodiment where the housing 5 incorporates a pivot member or fulcrum 11 . 6 for engagement with an upper end 11 . 8 of a rigid support 11 .
[0049] [0049]FIGS. 10A and 10B show a rigid support 11 attached to and spaced from a housing 5 by resilient biasing means 11 . 4 and attachment means 11 . 1 such that, upon application and removal of a downward force 14 , at least a portion of the resilient biasing means 11 . 4 will deform thus enabling the rigid support to oscillate and the cleaner 1 to advance across the surface to be cleaned. The degree of oscillation of the rigid support 11 may be controlled by the degree of flexibility, elasticity, length, thickness and shape of attached resilient biasing means 11 . 4 .
[0050] [0050]FIG. 11 provides an example of a rigid support 11 mounted to the housing 5 of a cleaning device 1 and oriented at an inclination to the surface 2 to be cleaned by resilient biasing means 11 . 4 . The support 11 includes an upper end 11 . 8 shaped for pivotal engagement with a pivot member 11 . 6 integrally formed with an adjacent support member 11 .
[0051] As stated, in order to achieve forward movement in response to vibration, the free end of each support must be capable of movement of up to a few millimeters. The rigid (i.e. supports which do not bend and straighten along their length), spring loaded supports 11 like those illustrated in FIGS. 1 through 11 achieve this by being oriented at an inclination relative to the surface 2 to be cleaned and by attachment to the cleaning device 1 in a manner which will enable the supports 11 to oscillate about an axis generally lateral to a downward force 14 . As disclosed below, alternative support configurations can achieve the required movement of their free ends by other means.
[0052] [0052]FIGS. 12A, 12B, 13 A, 13 B provide examples of resilient friction supports 30 , all of which are attached and oriented such that the point of contact by each support's free end 30 . 2 against the surface 2 to be cleaned is directly below the point of attachment 30 . 3 of the support 30 relative to the housing 5 (i.e. in this context the supports are not inclined, at least not in a specific common direction). The shape or geometry of the support between the latter points is designed such that, upon intermittent application of a downward force 14 , at least a portion of the support will deform and thus produce a resultant force including a component capable of moving the cleaner device 1 in step by step increments in a forward direction 13 , such increments indicated in the FIGS. by the dimension “e” in relation to a point “A” against the surface 2 .
[0053] [0053]FIGS. 14A and 14B show a resilient support 40 , a least a portion of which is circular in cross-section and attached such that the point of contact “A” against the surface 2 to be cleaned is directly below the point of attachment 40 . 3 of the support 40 relative to the housing 5 (i.e. the support is not inclined). The free end 40 . 2 of the support 40 need not be in contact with the surface 2 . Upon intermittent application of a downward force 14 , at least a portion of the support will deform and the portion of support 40 . 4 initially in contact with the surface 2 at point A will move in a direction which may be out of contact with the surface 2 . The new point of contact of the support 40 . 5 with the surface 2 will remain substantially below the point of attachment 40 . 3 relative to the housing 5 . The cleaner device 1 will thus move in step by step increments in a forward direction 13 , such increments indicated in the FIGS. by the dimension “e” in relation to a point “A” against the surface 2 . Along the portions of the support 40 . 4 , 40 . 5 which make contact with the surface 2 , friction grip enhancing treads or other means may be attached to or be integrated into the support 40 .
[0054] [0054]FIGS. 15A, 15B, 16 A, 16 B, 17 A and 17 B illustrate supports 50 which are spaced from the housing 5 and have at least two points of attachment 50 . 1 with respect to the housing 5 such that lines drawn between the points of attachment 50 . 1 of each support 50 and the point of contact by each support's free end 50 . 2 against the surface to be cleaned will not incline in a common direction. Upon intermittent application of a downward force 14 , flexible elements 50 . 3 , predisposed to deform in a particular manner, will deform in such manner and thereby cause movement of the cleaner device 1 in step by step increments in a forward direction 13 , such increments indicated in the FIGS. by the dimension “e” in relation to a point “A” against the surface 2 .
[0055] FIGS. 18 - 29 illustrate elevation views of alternate embodiments of friction supports.
[0056] It is to be understood that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. | A swimming pool cleaner is operable through a vibratory movement of its housing through a flow of water past a vibratory element carried within the housing . A friction support is carried by the housing and engages a surface to be cleaned. The friction support has a first end pivotally attached to the housing and a second free end in frictional contact with the surface to be cleaned. The friction support is further biased toward a first orientation and limited in its movement therefrom as the friction support is displaced during vibration of the housing and movement of the pool cleaner. | 4 |
This Application is a continuation of application Ser. No. 09/030,499, filed Feb. 25, 1998, now U.S. Pat. No. 6,689,089.
BACKGROUND OF THE INVENTION
The present invention concerns generally a medical device. More specifically, the present invention concerns a therapeutic catheter for treatment of vessels in a patient. The present invention includes catheters having proximal sensors for measuring changes at the distal end of the catheter.
DESCRIPTION OF RELATED ART
A therapeutic catheter having at last two channels or lumens extending through it in the longitudinal direction is known from EP-A-0 527 312 (corresponds to DE 41 26 886 A1). One lumen is a flow channel to supply liquid with high pressure (for example, 75 bar), from the near or proximal end to the far or distal end of the catheter. The catheter has an open flow path on its distal end at which the liquid in the form of a sharp jet can separate parts of a body tissue in a patient and convey them into the other lumen, which serves as return channel and transports the liquid together with the separated tissue material to the proximal end of the catheter. A similar or therapeutic catheter is also known from the published Patent Application DE 42 01 992 A1. Other known therapeutic catheters, like the one known from U.S. Pat. No. 5,380,273, have one or even two expansion elements, so-called dilation balloons, on the distal end with which blood vessels in a patient can be dilated or blocked. Moreover, mechanical catheters with a rotating tool on their distal end section to remove material in vessels of a patient are known from U.S. Pat. No. 5,092,872 and the unexamined German Applications DE 38 01 318 A1, DE 38 28 478 A1 and DE 43 23 756 A1. PCT-WO 89/09029 also exhibits a mechanical catheter with pivotable tools on the distal catheter end.
During introduction of a catheter into a patient the physician can observe the position of the catheter on an x-ray screen. However, the tissue or condition of the tissue is not recognizable or not clearly recognizable on the x-ray screen. The physician is therefore not capable of checking the therapeutic success on-line during therapy. He receives no feedback as to whether a vascular obstruction, for example, has been sufficiently eliminated. He is forced to adopt an iterative procedure “therapy, control, therapy, and so forth” in which the physician must rely on his experience and feelings in establishing the control intervals. This procedure leads to frequent control angiographies which expose the patient to radiation and contrast agents.
To summarize, this means that, when therapeutic catheters of the aforementioned types are used combined with x-ray imaging devices, the user only receives information concerning the position of the catheter in the patient, but the actual therapeutic function is not visible.
A hydrodynamic thrombectomy catheter in which fluid is guided via a channel system to treat the patient tissue and ultrasound is guided via a separate system to the tip of the catheter for optical monitoring of catheter operation is known from EP 0 483 133 A1. The therapy channel for the fluid and the diagnosis channel for the ultrasound diagnosis are separate and independent of each other.
In catheters in which laser radiation or ultrasound is used to treat patient tissue, the function of the catheter tip in a patient tissue can be monitored simply by reflecting laser beams or ultrasound waves. Such catheters are known, for example, from the following documents: publication of the article “Laser-induced Shockwave Lithotripsy with Microsecond Laser Pulses” in the journal Laser und Optoelektronik 20(4)/1988 by R. Engelhardt, W. Meyer, S. Thomas, P. Oehlert; published Patent Applications DE 43 22 955 A1 and DE 195 22 310 A1; Patent DE 42 40 182 C2, U.S. Pat. No. 5,104,392 and EP 0 582 766 A1. Moreover, a therapeutic catheter for treatment of patent tissue with laser light having an additional internal hollow channel to which a laser beam is transmitted for diagnostic purposes is known from DE 44 37 578 A1. Several therapeutic catheters are also known from EP 0 629 380 A1: a catheter for elimination of stenoses by laser radiation, a catheter with an expandable balloon on the distal end of the catheter to eliminate stenoses, and a catheter to treat patient vessels with ultraviolet light to prevent new formation of stenoses in blood vessels of the patient. No diagnostic possibilities are provided in these last-named catheters.
SUMMARY OF THE INVENTION
The invention is supposed to solve the task of devising a possibility in catheters having fluid channels and/or mechanical tools for therapeutic treatment of patient vessels, through which a signal can be generated in simple fashion, providing the user with information concerning the therapeutic effect of his work with the catheter in a patient.
Catheters according to the present invention can include a fluid channel extending at least from the proximal end to the distal end, and in some embodiments, return from the distal end to the proximal end. External changes in environment of the fluid in the distal end section of the catheter can cause one or more physical values or value changes to the fluid. The value changes can be measured at the proximal end of the catheter.
In one aspect of the invention, sensors or measurement devices on the proximal section of the catheter can measure physical changes in the fluid which are caused by external conditions acting on the fluid in the distal section of the catheter. In one embodiment, the distal section has an expandable element such as an inflatable balloon which can be inflated by fluid in the fluid channel. Sound or pressure can be measured at the proximal end of the catheter. In another embodiment of the invention, the distal section can include an open portion having hydrodynamic jet which can be used to break up a vessel occlusion and sweep broken pieces proximally through the fluid channel. Sound or pressure changes in the fluid caused by changes at the distal end can be measured at the proximal end. In yet another embodiment, a rotating tool at the distal end can be driven by a rotating shaft extending from the distal end to the proximal end. Changes in torque at the proximal end can be measured. The proximally measured changes can be output as optically or acoustically recognizable signals or values. Some embodiments have an acoustic signal generator for converting the detected or measured values into acoustic signals audible to persons.
The fundamental idea of the invention is as follows: when therapeutic catheters are used in which the energy is transported in the form of a liquid or gaseous fluid under pressure or in the form of mechanical energy from the proximal end section to the distal end section, especially to the catheter tip of the catheter and used there for therapy in a patient, the energy is altered by feedback from the patient tissue. Or in other words, the magnitude and type of energy released at the catheter tip to the surroundings is changed by feedback from these surroundings to this energy. In a gaseous or liquid fluid under pressure for removal of material in patient vessels, the pressure of the fluid is changed as a function of the flow resistance of the fluid between the distal end section of the catheter and its surroundings, which is formed by the patient tissue.
Noise also develops in the fluid stream and thus sound waves as a function of whether the fluid encounters patient tissue and/or ablates the patient tissue and/or the ablated or cut patient tissue is drawn by the fluid into the fluid channel. These pressure changes and/or noise or sound waves occurring on the distal end section of the catheter are determined according to the invention on the proximal end section of the catheter by a sensor or measurement device and made acoustically audible [sic] or visually visible [sic] for an operating person of the catheter. Because of this the operating person with reference to this acoustic or optical signal can recognize whether the fluid and in which way the fluid is acting on a patient tissue in a patient. In similar fashion the torque and/or noise developments of a drive shaft, which drives a rotating tool on the distal end of the catheter, are measured by the invention during use of mechanical catheters in the therapeutic treatment of patient vessels. An acoustic and/or visible signal or measurement result is generated as just described from these measurements, with reference to which an operating person can recognize and evaluate the effect of the rotating tool on a patient vessel in a patient. These changes in energy in the form of pressure changes, sound generation or sound changes or torque and torque changes which occur on the distal end section of the catheter, are determined or measured by the invention on the proximal end section of the catheter, during which this measurement is conducted in the same fluid or in the same mechanical element on the proximal end section of the catheter that conveys the energy to the distal end section of the catheter. Thus, according to the invention, the same channel and the same fluid or the same mechanical element is used for therapy of the patient as for signal production. By connecting a sensor or measurement element to the fluid channel or the mechanical drive element on the proximal end section of the catheter the aforementioned changes are recorded and made visible and/or audible to the user. The treatment medium “fluid” or “drive element” thus has a dual function, in which it serves both for therapy and energy transmission from the proximal end section to the distal end section of the catheter and in the opposite direction as an information path from the distal end section to the proximal end section of the catheter. No information path in addition to the therapy path is required for information transmission.
Additional features of the invention are contained in the subclaims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described below with reference to the drawings of preferred variance. In the drawings
FIG. 1 schematically depicts a device with a balloon catheter for therapeutic treatment,
FIG. 2 schematically depicts a device with a mechanical catheter with a rotating shaft,
FIG. 3 schematically depicts a device with a high-pressure fluid catheter for removal of vessel parts in a patient with acoustic and optical means of indication for pressure and/or sound and/or flow rate of the fluid in the catheter.
DETAILED DESCRIPTION OF THE INVENTION
The invention concerns therapeutic catheter a) according to FIG. 1 in the form of balloon catheters (PTA, PTCA) with one or more expandable balloons on the distal end section, in which the measurable form of energy is the pressure and/or volume of a liquid or gas; b) according to FIG. 2 in the form of mechanical catheters whose measurable form of energy is the torque of a rotating tool or a rotating shaft, or changes of this form of energy in the form of sound waves that are generated in mechanical rotating objects during interaction with a patient vessel; c) according to FIG. 3 in the form of hydrodynamic catheters whose measurable form of energy is the kinetic energy and/or the flow rate of the fluid and/or the noise development in the fluid during flow through the catheter, in which the fluid can be liquid or gas.
FIG. 1 schematically depicts a device with a balloon catheter 102 , which has a proximal end section 104 and a distal end section 106 . The distal end section 106 has one or more radially expandable balloons 108 arranged axially in sequence with which blood vessels can be blocked or narrowed blood vessels 12 widened. For this purpose the corresponding balloon 108 can be expanded with fluid from a fluid source 110 mounted on the proximal end section 104 , which can be a liquid or gas, which flows through at least one therapy and information channel 116 of catheter 102 . For this purpose a fluid is conveyed at a predetermined volume or pressure of the fluid source 110 into the corresponding balloon 108 . The fluid source can be a hand-operated piston-cylinder unit or a syringe. The pressure required to fill balloon 108 with a predetermined volume depends on the condition, especially the opening cross section, of the blood vessel 12 to be expanded. In a severely constricted blood vessel 12 a much greater pressure is required to fill the corresponding balloon 108 with a predetermined volume than in an unconstricted or only slightly constricted blood vessel 12 . The time trend of volume and the time trend of pressure during filling of the balloon or balloons 108 can be detected or measured by sensors or means of measurement 114 on the proximal end section 104 of catheter 102 and provide an experienced operating person with acoustic and/or optical information concerning the position and effect of the balloon 108 in blood vessel 12 and concerning the state of blood vessel 12 . The operating person knows the values of a healthy and normal vessel of a comparable person in comparison with these detected or measured values or, if the patient is an animal, of a comparable animal. During filling of the balloon or balloons 108 the fluid flows through channel 116 in direction 117 to the distal end section 106 , whereas during emptying of balloons 108 the fluid flows in the opposite direction 118 through the same (or another) channel 116 to the proximal end section 104 back to the fluid source 110 or to a means of ventilation or storage.
FIG. 2 schematically depicts a device with a mechanical catheter 302 provided with a rotatable shaft extending through it lengthwise. Such mechanical catheters 302 are used, in particular, but not only for thrombectomy and arthrectomy. The shaft 320 is driven by a motor 310 on the proximal end section 304 so that a tool 322 fastened on its distal end can process vascular material on the distal end section 306 of the catheter in a vessel 12 of a patient, for example, ablate, fragment or destroy it. The ablated or fragmented vascular material can remain in the patient or be conveyed by appropriate means to the proximal end section 304 . The torque of shaft 320 depends on how great the resistance of vessel 12 is in the patient to the tool 322 on the distal end of the shaft. The corresponding torque and torque changes of shaft 320 can be measured by a torque sensor 314 on the proximal end section 304 of the catheter. This means that the shaft 320 transmits information from the distal end section 306 to the proximal end section 304 in the form of torque or torque changes, which are measured by torque sensor 314 and optically and/or acoustically displayed. The torque can be displayed as torque or in other measurement units which are a gauge for the operating person of the condition of vessel 12 and the activity of tool 322 in this vessel 12 . The torque sensor 314 can have two angle sensors 324 and 325 arranged on shaft 320 and a torsion spring 326 arranged between them and attached to them, with which the torque transferred by shaft 320 and thus the torque changes can be measured. The energy transmission for therapy of the patient also occurs here through the same element, namely through shaft 320 , from the proximal end section 304 to the distal end section 306 of catheter 302 according to arrow 317 and the information flow concerning the condition of the vessel 12 and the type and scope of the effect of tool 322 on the vessel 12 occurs in the opposite direction according to arrows 318 through the same shaft 320 from the distal end section 306 to the proximal end section 304 . The shaft 320 thus has the function of both a therapeutic element and an information transmission element.
FIG. 3 shows an apparatus with a hydrodynamic catheter 402 for therapeutic treatment of a vessel 12 in a patient with a gaseous or preferably liquid fluid under pressure. The catheter 402 contains a fluid path consisting of a flow channel 430 , a path section 432 open to the outside surroundings on the distal end section 406 of the catheter and a return channel 438 . A pressurized fluid source 410 can convey a pressurized fluid, for example, gas or preferably liquid at very high pressure of, say, 75 bar, on the proximal end section 404 of catheter 402 into the flow channel 430 in the direction of arrow 417 . The pressurized fluid arrives at the distal end section 406 of catheter 402 in the form of a sharp fluid jet in the open path section 432 , treats the vessel 12 there, for example, cuts or fragments the vascular constriction material 434 and then flows into the distal end 436 of the return channel 438 with entrainment of material 434 and then through the latter in the direction of arrow 418 to the proximal end section 404 to a container 440 . A pressure sensor 414 with a defined hydraulic resistance is connected on the proximal end section 404 of return channel 436 . The pressure sensor 414 measures the pressure drop over the hydraulic resistance. The measured pressure varies as a function of flow resistance of the fluid in the flow path of the catheter, for example, the size of the vascular constriction 434 , and as a function of whether and how much material 434 and possibly blood is conveyed by the pressurized fluid from the vessel 12 of the patient in the return channel 438 . The pressure measured by pressure sensor 414 on the proximal end section 404 in return channel 438 is therefore information concerning whether and how the pressurized fluid acts on vessel 12 and what the state of vessel 12 is and whether the pressurized fluid stream is transporting much, little or no vascular constriction material 434 , and also information concerning how the distal end section 406 is positioned relative to the location 434 of vessel 12 being treated. The same pressurized fluid therefore transmits via the same fluid path 430 , 432 , 438 , both the energy for therapy of vessel 12 and also information for the person using the catheter 402 .
The pressure sensor 414 of FIG. 3 is connected via an electronic signal evaluation circuit 442 to an optical display device 444 and/or to an acoustic signal generator 446 , especially an earphone or loudspeaker. The optical display device 444 shows the user of catheter 402 the aforementioned information. The acoustic signal generator 446 generates tones or noises that the user can hear, depending on the information.
The electronic evaluation circuit 442 , the optical display device 444 and the acoustic signal generator 446 can also be used in combination with sensors 114 and 314 of the other FIGS. 1 and 2 in order to convert their signals into an optical display signal and/or an acoustic indication signal.
In the variants according to FIGS. 1 and 3 the fluid can be passed through several channels in parallel instead of through one channel.
Noises develop in the pressurized fluid with a catheter 102 of FIG. 1 and catheter 402 of FIG. 3 as a function of whether the pressurized fluid flows quickly or slowly, whether it fragments particles of vessel 12 and/or whether it changes its pressure. These noises are information concerning the state of vessel 12 and the effect of the pressurized fluid on the distal end section of the catheter. In similar fashion noises develop in the shaft 320 of catheter 302 of FIG. 2 and thus information as a function of the state of vessel 12 and the effect of tool 322 on the distal end section of the catheter. Preferred variants therefore consist of the fact that the sensor 114 of FIG. 1 , the sensor 314 of FIG. 2 and the sensor 314 of FIG. 3 are noise or sound sensors and have means for optical and/or acoustic indication of information, preferably loudspeakers or earphones.
In all variants the information can be recorded and stored automatically in electronic or other means of storage. | Apparatus with a pneumatic or hydraulic or mechanical therapeutic catheter. The therapy energy required to treat internal vessels of the patient is transferred by the same fluid or the same elements from the proximal end section to the distal end section of the catheter that transfer information from the distal end section to the proximal end section of the catheter. The information provides understanding of the estate of the vessel and how the therapy fluid of the therapy element of the catheter acts on the vessel. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a photoelectric conversion apparatus and an image pickup system, and more particularly to a photoelectric conversion apparatus and an image pickup system both of which include a plurality of light receiving portions arrange on a semiconductor substrate, an antireflective film formed above the light receiving portions with an insulation film put between them, and color filter layers of a plurality of colors formed on the antireflective film.
[0003] 2. Description of Related Art
[0004] As a solid state image pickup device, a charge coupled device (CCD) type photoelectric conversion element has conventionally been used in many cases. However, a complementary metal oxide semiconductor (CMOS) type photoelectric conversion element has been reconsidered recently, and a trend of commercialization of product of the CMOS type photoelectric conversion element has been generated owing to the merits of the CMOS type photoelectric conversion element such as its power consumption lower than that of the CCD type photoelectric conversion element, its operability of the use of a single power supply, and its producibility of its light receiving portion and its peripheral circuits by the same CMOS process, which makes it easy to integrate the CMOS type photoelectric conversion element.
[0005] As the configuration of a conventional solid state image pickup device, for example, there is one proposed in Japanese Patent Application Laid-Open No. 2000-12822. An example of the pixel configuration of the disclosed metal oxide semiconductor (MOS) type solid state image pickup device is shown in FIG. 9 . The MOS type solid state image pickup device shown in FIG. 9 is a solid state image pickup device adopting a method in which signal charges are transferred from light receiving portions to detection portions to output potential changes generated by the detection portions. Each pixel of the MOS type solid state image pickup device is composed of a light receiving portion and four transistors of a transfer transistor, an amplifying transistor, a reset transistor and a selection transistor. The transfer transistor is a MOS transistor composed of a light receiving portion 43 , a detection portion 44 a , both of which are n type diffusion regions formed in a p type silicon substrate 40 , and a transfer gate electrode 42 formed above the silicon substrate between both the regions with an insulation film 41 put between the transfer gate electrode 42 and the silicon substrate. The transfer transistor uses the light receiving portion 43 and the detection portion 44 a as its source and its drain, respectively.
[0006] An antireflective film 45 a is formed above the light receiving portion 43 with the insulation film 41 put between them. In such a configuration, by the interference caused by the antireflective film 45 a (silicon nitride film) and the insulation film (silicon oxide film) 41 , and by the interference caused by the films including the above-mentioned two films and an interlayer insulation film formed above the two films, the reflection of light at an interface between the silicon and the silicon oxide film is suppressed to enable the sensitivity to be improved. A reference numeral 46 a denotes an insulation film (silicon oxide film); a reference numeral 44 b denotes an electric field relief region; reference numerals 45 b and 46 b denote side insulation films (silicon nitride film and silicon oxide film).
SUMMARY OF THE INVENTION
[0007] However, the present inventor found that there was a problem that the variation of the film thicknesses of the antireflective films and the variation of the film thicknesses of the insulation films were produced owing to the variation of the film thicknesses at processing processes and the light transmittance changes according to wavelengths to produce the differences of color ratios of B/G and R/G in the case where a color filter is formed on the antireflective film of the configuration of the above-mentioned Japanese Patent Application Laid-Open No. 2000-12822.
[0008] It is an object of the present invention to propose a designing technique of an antireflective film in which no differences of the color ratios of B/G and R/G are produced to realize a photoelectric conversion apparatus having a good color reproducibility even when the film thicknesses of antireflective films and insulation films vary at processing processes.
[0009] For achieving the above-mentioned object, the present invention is a photoelectric conversion apparatus including a plurality of light receiving portions arranged on a semiconductor substrate, antireflective films formed on the light receiving portions, and color filter layers of a plurality of colors formed on the antireflective films, wherein film thicknesses of the antireflective films are changed such that changing directions of spectral transmittances at peak wavelengths of color filters on sides of the shortest wavelengths and at peak wavelengths of color filters on sides of the longest wavelengths after transmission of infrared cutting filters may be the same before and after changes.
[0010] Moreover, the present invention is a photoelectric conversion apparatus including a plurality of light receiving portions arranged on a semiconductor substrate, antireflective films formed on the light receiving portions, and color filter layers of a plurality of colors, the color filter layers formed on the antireflective films, wherein the antireflective films are severally made of a silicon nitride film having a film thickness within a range from 25 nm to 40 nm, and silicon oxide films each having a film thickness of 8 nm or less are formed between the light receiving portions and the antireflective films.
[0011] Moreover, the present invention is a photoelectric conversion apparatus including a plurality of light receiving portions arranged on a semiconductor substrate, antireflective films formed on the light receiving portions, and color filter layers of a plurality of colors, the color filter layers formed on the antireflective films, wherein the antireflective films are severally made of a silicon oxynitride film having a film thickness within a range from 40 nm to 60 nm, and silicon oxide films each having a film thickness of 8 nm or less are formed between the light receiving portions and the antireflective films.
[0012] In the present invention, the antireflective films are films for suppressing reflection on a substrate surface, which reflection is caused by a difference of refractive indices of the substrate and the insulation films, and the antireflective films are films for suppressing reflection on a substrate surface, which reflection is caused by a difference of refractive indices of the substrate and the antireflective films, in the case where the insulation films are not formed between the antireflective films and the substrate.
[0013] According to the present invention, no differences of color ratios between B/G and R/G are produced even when film thicknesses of antireflective films and insulation films vary at processing processes, and a photoelectric conversion apparatus having a good color reproducibility can be realized.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a view showing the configuration of a photoelectric conversion apparatus of an embodiment of the present invention;
[0015] FIG. 2 is a characteristic diagram of spectral transmittances in the case where the film thickness of a silicon oxide film as an insulation film is 8 nm and the film thickness of a silicon nitride film as an antireflective film is 40 nm;
[0016] FIG. 3 is a characteristic diagram of spectral transmittances as a first comparative example in the case where the film thickness of a silicon oxide film as an insulation film is 8 nm and the film thickness of a silicon nitride film as an antireflective film is 50 nm;
[0017] FIG. 4 is a characteristic diagram of spectral transmittances as a second comparative example in the case where the film thickness of a silicon oxide film as an insulation film is 10 nm and the film thickness of a silicon nitride film as an antireflective film is 40 nm;
[0018] FIG. 5 is a diagram showing a designing technique according to a first example of the present invention;
[0019] FIG. 6 is a diagram showing a designing technique according to a second example of the present invention;
[0020] FIG. 7 is a diagram showing a designing technique according to a third example of the present invention;
[0021] FIG. 8 is a block diagram showing a case where a solid state image pickup apparatus of the present invention is applied to a still video camera;
[0022] FIG. 9 is a schematic sectional view showing a conventional solid state image pickup apparatus;
[0023] FIG. 10 is a diagram showing an example of a designing technique according to a conventional antireflective film; and
[0024] FIG. 11 is a diagram showing a principle of the increase of color variations in a conventional example.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] In the following, the attached drawings are referred to while the preferred embodiments of the present invention are described.
[0026] First, the circumstances of the achievement of the present invention are described. An example of the conventional designing technique of the film thicknesses of an insulation film and an antireflective film is shown in FIG. 10 . The ordinate axis of the graph is transmittance (%), and the abscissas axis of the graph is wavelength (μm). The diagram shows how much of the incident light of each wavelength is transmitted to reach a light receiving portion. A reference numeral 501 denotes a spectral characteristic in case of no antireflective films are used, and a reference numeral 502 denotes a spectral characteristic after designing the optimal value of the antireflective film.
[0027] In the conventional designing technique, designing has been performed to adopt a combination of the thicknesses of the antireflective film 45 a and the insulation film 41 in order to show the characteristic which is denoted by the reference numeral 502 in FIG. 10 and is one in which the transmittance (sensitivity) of the wavelength takes the maximum value at the center (near to green). The reason why the conventional designing technique has taken the designing is that the rise of the sensitivity at the central frequency (near to green) would raise the sensitivities at the short wavelength side (near to blue) and the long wavelength side (near to red) at the same time.
[0028] The present inventor found the following fact. That is to say, when the antireflective films 45 a and the insulation films 41 are manufactured by the above-mentioned designing technique, the variations of the film thicknesses of the antireflective films 45 a and the insulation films 41 are produced owing to the unevenness of etching at the time of etching a gate oxide film and the unevenness of deposition at the time of depositing the antireflective film in the processing processes. The differences of color ratios of B/G and R/G become large owing to the variations of the film thicknesses, and then the color reproducibility of sensors becomes bad.
[0029] Table 1 shows variations of color ratios of sensors manufactured by the conventional technique (at the time of supposing that B=450 nm, G=550 nm and R=630 nm). The standard deviation value of ten chips extracted randomly is expressed by σ.
[0030] According to the conventional technique, the variation of B/G is 4.28% at the time of being expressed by the σ, and the variation of R/G is 4.83% at the time of being expressed by the σ.
[0000]
TABLE 1
CHIP
B/G
R/G
1
1.02
0.95
2
1.05
0.94
3
1.05
0.96
4
0.97
1.03
5
1.04
0.99
6
1.08
0.94
7
0.98
1.06
8
1.01
1
9
0.95
1.04
10
1.06
0.92
σ
0.0428
0.0483
[0031] FIG. 11 shows the principle of the enlargement of the variations. A dotted line 601 indicates a spectral characteristic at the time of designing the antireflective film to have the optimum value. A solid line 602 indicates a spectral characteristic at the time when the antireflective film varies toward the thinner direction. A solid line 603 indicates a spectral characteristic at the time when the antireflective film varies toward the thicker direction. When the antireflective film is designed in accordance with the conventional technique, a point 604 where the spectral curve at the time when the film thickness of the antireflective film varies toward the thinner direction and the spectral curve at the time when the film thickness of the antireflective film varies toward the thicker direction of the antireflective film intersect with each other exists at a wavelength near to 550 nm. At the cross point, changing directions on the blue side and the red side reverse. Consequently, when a variation is produced in film thicknesses, the transmittance at a point G (550 nm) does not change so much, but the transmittances at points B (450 nm) and R (630 nm) change greatly. Consequently, large differences of values of color ratios B/G and R/G are produced, and the differences make the color reproducibility bad.
[0032] On the basis of the circumstances described above, the present inventor varied film thicknesses of the insulation films and the antireflective films, and examined them. Consequently, the inventor found that the film thicknesses of the insulation films and the antireflective films could be set in order that the changing directions of the spectral transmittances might be the same at the peak wavelength of the color filter on the side of the shortest wavelength and on the side of the longest wavelength after the transmission of an infrared cutting filter. To put it more concretely, the inventor found that the changing directions of the spectral transmittances were the same when the film thickness of a silicon oxide film used as the insulation film is 8 nm or less and the film thickness of a silicon nitride film used as the antireflective film is within a range from 25 nm to 40 nm. Moreover, the inventor also found that the changing directions of the spectral transmittances were the same when the film thickness of a silicon oxide film used as the insulation film is 8 nm or less and the film thickness of a silicon oxynitride film used as the antireflective film is within a range from 40 nm to 60 nm.
[0033] FIG. 1 shows the configuration of a photoelectric conversion apparatus of the present embodiment. The photoelectric conversion apparatus of the present embodiment adopts a configuration made by providing an Al wiring layer 33 above the solid state image pickup apparatus of the Japanese Patent Application Laid-Open No. 2000-12822, shown in FIG. 9, with an interlayer film (SiO 2 ) 30 put between them, and by providing an Al wiring layer 34 above the Al wiring layer 33 with an interlayer film (SiO 2 ) 31 put between them, and further by providing a flattening layer 35 , a color filter (CF) layer 36 and a flattening layer 37 above the Al wiring layer 34 with an interlayer film (SiO 2 ) 32 put between them. The photoelectric conversion apparatus is further provided with a microlens 38 . The same configuration members as those of the solid state image pickup apparatus of FIG. 9 are here denoted by the same reference marks as those in FIG. 9 , and their descriptions are omitted.
[0034] However, in the case where the decrease of the reflection light should be first considered rather than the problems pertaining to processes such as the increase of dark currents in pixels and the increase of white spots, the insulation film 41 is not always formed on the light receiving portion 43 . This fact is applied to all of the examples described in the following.
[0035] FIG. 2 is a spatial transmittance characteristic diagram of an embodiment of the present invention, in which the thicknesses of the insulation film and the antireflective film are within the above-mentioned range. That is to say, FIG. 2 shows the spectral transmittances in the case where the thickness of a silicon oxide film as the insulation film is 8 nm and the thickness of a silicon nitride film as the antireflective film is 40 nm. FIG. 3 is a spectral transmittance characteristic diagram as a first comparative example, in which the thickness of the silicon oxide film as the insulation film is 8 nm and the thickness of the silicon nitride film as the antireflective film is 50 nm. FIG. 4 is a spectral transmittance characteristic diagram as a second comparative example, in which the thickness of the silicon oxide film as the insulation film is 10 nm and the thickness of the silicon nitride film as the antireflective film is 40 nm. A reference numeral 51 denotes a spectral characteristic in the case where the antireflective film has a designed thickness value. A reference numeral 52 denotes a spectral characteristic in the case where the antireflective film becomes thicker by 10% owing to a variation. A reference numeral 53 denotes a spectral characteristic in the case where the antireflective film becomes thinner by 10% owing to a variation. A reference numeral 54 denotes a spectral characteristic of a blue color filter. A reference numeral 55 denotes a spectral characteristic of a green color filter. A reference numeral 56 denotes a spectral characteristic of a red color filter after the transmission of an infrared cutting filter. The peak wavelengths of the respective filters are 450 nm, 550 nm and 630 nm in the blue color filter, the green color filter and the red color filter, respectively.
[0036] As shown in FIG. 2 , as long as the film thicknesses of the insulation film and the antireflective film are within the above-mentioned range of the embodiment of the present invention, the changing directions of the spectral characteristics between the peak wavelengths of 450 nm and 630 nm of the blue color filter and the red color filter, respectively, are the same. On the other hand, as shown in FIGS. 3 and 4 , in the case where the film thicknesses of the insulation film and the antireflective film are out of the above-mentioned range of the embodiment of the present invention, it can be found that the changing directions of the spectral characteristics between the peak wavelengths of 450 nm and 630 nm of the blue color filter and the red color filter, respectively, are not the same, and that the changing directions of the blue side and the red side are reversed.
Example 1
[0037] In accordance with claim 1 of the present invention, after the insulation film of the photoelectric conversion apparatus of FIG. 1 was formed to be 8 nm thick as a silicon oxide film and the antireflective film was formed to be 30 nm thick as a silicon nitride film, wiring layers were formed. Thereby, a photoelectric conversion apparatus including formed color filter layers of red, green and blue was made. The present example was made to have a variation in the antireflective film. FIG. 5 shows a spectral characteristic of the present example. A reference numeral 101 denotes a spectral characteristic in the case where the antireflective film takes a designed value (30 nm). A reference numeral 102 denotes a spectral characteristic in the case where the antireflective film is thicker by 10% (33 nm) owing to a variation. A reference numeral 103 denotes a spectral characteristic in the case where the antireflective film is thinner by 10% (27 nm) owing to a variation. A reference numeral 104 denotes the spectral characteristic of the blue color filter. A reference numeral 105 denotes the spectral characteristic of the green color filter. A reference numeral 106 denotes the spectral characteristic of the red color filter after the transmission of an infrared cutting filter. The peak wavelength of each filter of blue, green and red is: 450 nm, 550 nm and 630 nm, respectively.
[0038] The spectral characteristics of the photoelectric conversion apparatus made under the above-mentioned conditions are ones shown in FIG. 5 . The spectral characteristics has a feature such that the changing directions of the spectral characteristic (102) in the case where the antireflective film is thicker by 10% and the spectral characteristic (103) in the case where the antireflective film is thinner by 10% are the same between the peak wavelength 450 nm of blue and the peak wavelength 630 nm of red. This tendency was especially notable when the film thickness of the antireflective film was within a range from 25 nm to 40 nm. In the case where the silicon oxide film was not provided below the antireflective film, also the same tendency was exhibited.
[0039] Table 2 shows variations of color ratios of a sensor made by the technique of Example 1. (It is supposed that B=450 nm, G=550 nm and R=630 nm.) Ten chips were randomly extracted, and the values of B/G and R/G of each chip were measured. The standard deviation values σ of the ten chips were obtained to the respective R/G and B/G. By the technique of Example 1, the variation of the B/G was 0.99% when being expressed by σ, and the variation of the R/G was 0.94% when being expressed by σ.
[0000]
TABLE 2
CHIP
B/G
R/G
1
1.01
1.00
2
1.00
0.99
3
1.00
1.01
4
0.99
1.00
5
0.98
1.02
6
1.01
1.00
7
1.00
0.99
8
1.01
0.99
9
1.00
1.00
10
0.99
1.00
σ
0.0099
0.0094
[0040] Because the changing directions of the spectral transmissions are the same between the peak wavelength of blue and the peak wavelength of red by the technique of Example 1, the color ratio variations were improved by 3% in comparison with that by the conventional technique (Table 1). Consequently, a photoelectric conversion apparatus having better color reproducibility in comparison with the one by the conventional technique was realized.
Example 2
[0041] In accordance with claim 1 of the present invention, after the insulation film of the photoelectric conversion apparatus of FIG. 1 was formed to be 8 nm thick as a silicon oxide film and the antireflective film was formed to be 30 nm thick as a silicon nitride film, wiring layers were formed. Thereby, a photoelectric conversion apparatus including formed color filter layers of red, green and blue was made. The present example was made to have a variation in the antireflective film. FIG. 6 shows a spectral characteristic of the present example. A reference numeral 201 denotes a spectral characteristic in the case where the antireflective film takes a designed value (8 nm). A reference numeral 202 denotes a spectral characteristic in the case where the antireflective film is thicker by 10% owing to a variation. A reference numeral 203 denotes a spectral characteristic in the case where the antireflective film is thinner by 10% owing to a variation. A reference numeral 204 denotes the spectral characteristic of the blue color filter. A reference numeral 205 denotes the spectral characteristic of the green color filter. A reference numeral 106 denotes the spectral characteristic of the red color filter after the transmission of an infrared cut filter. The peak wavelength of each filter of blue, green and red is: 450 nm, 550 nm and 630 nm, respectively.
[0042] The spectral characteristics of the photoelectric conversion apparatus made under the above-mentioned conditions are ones shown in FIG. 6 . The spectral characteristics has a feature such that the changing directions are the same between the peak wavelength 450 nm of blue and the peak wavelength 630 nm of red even if the insulating films were varied. This tendency was especially notable when the film thickness of the antireflective film was within a range from 6 nm to 8 nm. In the case where the silicon oxide film was not provided below the antireflective film, also the same tendency was exhibited.
[0043] Table 3 shows variations of color ratios of a sensor made by the technique of Example 2. (It is supposed that B=450 nm, G=550 nm and R=630 nm.) Ten chips were randomly extracted, and the values of B/G and R/G of each chip were measured. The standard deviation values σ of the ten chips were obtained to the respective R/G and B/G. By the technique of Example 2, the variation of the B/G was 0.57% when being expressed by σ, and the variation of the R/G was 0.67% when being expressed by σ.
[0000]
TABLE 3
CHIP
B/G
R/G
1
1.00
1.00
2
1.00
0.99
3
1.00
1.00
4
0.99
1.00
5
1.00
1.00
6
1.01
1.00
7
1.00
1.01
8
1.00
0.99
9
0.99
1.00
10
1.00
1.01
σ
0.0057
0.0067
[0044] Because the changing directions of the spectral transmissions are the same between the peak wavelength of blue and the peak wavelength of red by the technique of Example 2, the color ratio variations were improved by 3.5% or more in comparison with those by the conventional technique (Table 1). Consequently, a photoelectric conversion apparatus having better color reproducibility in comparison with the one by the conventional technique was realized.
Example 3
[0045] In accordance with claim 1 of the present invention, the insulation film of the photoelectric conversion apparatus of FIG. 1 was formed to be 8 nm thick as a silicon oxide film (n=1.66), and the antireflective film was formed to be 50 nm thick as a silicon oxynitride film. After that, wiring layers were formed. Thereby, a photoelectric conversion apparatus including formed color filter layers of red, green and blue was made. The present example was made to have variations in the antireflective film and in the insulation film. FIG. 7 shows spectral characteristics of the present example. A reference numeral 301 denotes a spectral characteristic in the case where the antireflective film takes a designed value. A reference numeral 302 denotes a spectral characteristic in the case where the antireflective film and the insulation film are severally thicker by 10% owing to a variation. A reference numeral 303 denotes a spectral characteristic in the case where the antireflective film and the insulation film are severally thinner by 10% owing to a variation. A reference numeral 304 denotes the spectral characteristic of the blue color filter. A reference numeral 305 denotes the spectral characteristic of the green color filter. A reference numeral 306 denotes the spectral characteristic of the red color filter. The peak wavelength of each filter of blue, green and red is: 450 nm, 550 nm and 630 nm, respectively.
[0046] The spectral characteristics of the photoelectric conversion apparatus made under the above-mentioned conditions are ones shown in FIG. 7 . The spectral characteristics has a feature such that the changing directions of the spectral characteristic (302) in the case where the antireflective film and the insulation film are thicker by 10% and spectral characteristic (303) in the case where the antireflective film and the insulation film are thinner by 10% are the same between the peak wavelength 450 nm of blue and the peak wavelength 630 nm of red. This tendency was especially notable when the film thickness of the insulation film was within a range from 6 nm to 8 nm and the antireflective film was within a range from 40 nm to 60 nm. In the case where the silicon oxide film was not provided below the antireflective film, also the same tendency was exhibited.
[0047] Table 4 shows variations of color ratios of a sensor made by the technique of Example 3. (It is supposed that B=450 nm, G=550 nm and R=630 nm.) Ten chips were randomly extracted, and the values of B/G and R/G of each chip were measured. The standard deviation values σ of the ten chips were obtained to the respective R/G and B/G. By the technique of Example 3, the variation of the B/G was 1.60% when being expressed by σ, and the variation of the R/G was 1.42% when being expressed by σ.
[0000]
TABLE 4
CHIP
B/G
R/G
1
1.02
0.98
2
1.00
0.99
3
0.98
1.01
4
0.99
1.01
5
1.00
1.00
6
1.01
0.98
7
1.03
0.97
8
1.00
0.99
9
0.98
1.01
10
1.00
0.99
σ
0.0160
0.0142
[0048] Because the changing directions of the spectral transmissions are the same between the peak wavelength of blue and the peak wavelength of red by the technique of Example 3, the color ratio variations were improved by 3.5% or more in comparison with those by the conventional technique (Table 1) when being expressed by σ. Consequently, a photoelectric conversion apparatus having better color reproducibility in comparison with the one by the conventional technique was realized.
[0049] Next, an image pickup system using the above-mentioned photoelectric conversion apparatus is described. Referring to FIG. 8 , the details of an embodiment in which the solid state image pickup device of the present invention is applied to a still camera are described.
[0050] FIG. 8 is a block diagram showing a case where the solid state image pickup device is applied to a “still video camera.”
[0051] In FIG. 8 , a reference numeral 1 denotes a barrier used as a protection of a lens and also used as a main switch. A reference numeral 2 denotes a lens for forming an optical image of a subject on a solid state image pickup device 4 . A reference numeral 3 denotes a diaphragm for changing the amount of light passing through the lens 2 . The reference numeral 4 denotes the solid state image pickup device for taking the subject imaged by the lens 2 as an image signal. A reference numeral 5 denotes a circuit processing image pickup signal. A reference numeral 6 denotes an A/D converter for performing the analog-digital conversion of an image signal output from the solid state image pickup device 4 . A reference numeral 7 denotes a signal processing unit for performing various corrections of the image data output from the A/D converter 4 and for performing the compression of the data. A reference numeral 8 denotes a timing generator for outputting various timing signals to the solid state image pickup device 4 , the circuit 5 processing image pick-up signal, the A/D converter 6 and the signal processing unit 7 . A reference numeral 9 denotes a unit of controlling whole and arithmetic operation for controlling various operations and the whole of the still camera. A reference numeral 10 denotes a memory unit for storing image data temporarily. A reference numeral 11 denotes an interface unit for performing the recording or the reading of a recording medium. A reference numeral 12 denotes the detachably mountable recording medium such as a semiconductor memory for performing the recording or the reading of image data. A reference numeral 13 denotes an interface unit for performing the communication with an external computer or the like.
[0052] Next the operation of the still video camera configured as above at the time of photographing is described.
[0053] When the barrier 1 is opened, the main power source is turned on. Next, the power source of the control system is turned on. Furthermore, the power source of the image pickup system circuits such as the A/D converter 6 is turned on.
[0054] Then, the unit of controlling whole and arithmetic operation 9 releases the diaphragm 3 for controlling light exposure. A signal output from the solid state image pickup device 4 is converted by the A/D converter 6 , and then is input to the signal processing unit 7 . According to the data of the signal processing unit 7 , the unit of controlling whole and arithmetic operation 9 performs the operation of an exposure.
[0055] The unit of controlling whole and arithmetic operation 9 judges brightness on the basis of a result of performing the photometry, and controls the diaphragm 3 according to the result of the judgment.
[0056] Next, the unit of controlling whole and arithmetic operation 9 extracts high frequency components on the basis of the signal output from the solid state image pickup device 4 , and performs the arithmetic operation of the distance from the still video camera to a subject. After that, the unit of controlling whole and arithmetic operation 9 drives the lens, and judges whether to be focused or not. When the unit of controlling whole and arithmetic operation 9 judges that the lens is not focused, the unit of controlling whole and arithmetic operation 9 again drives the lens and performs distance measuring.
[0057] After a focused state has been confirmed, the still video camera begins an actual exposure. When the exposure has been completed, an image signal output from the solid state image pickup device 4 receives an A/D conversion by the A/D converter 6 . Then, the converted digital data passes through the signal processing unit 7 to be written in the memory unit by the unit of controlling whole and arithmetic operation 9 .
[0058] After that, the data stored in the memory unit 10 is recorded in the detachably mountable recording medium 12 such as a semiconductor memory through the I/F unit for controlling recording medium under the control of the unit of controlling whole and arithmetic operation 9 . Alternatively, the data stored in the memory unit 10 can be directly input to a computer or the like through the external I/F unit 13 .
[0059] The present invention can be applied to an apparatus using an image pickup apparatus (photoelectric conversion apparatus) mounting a color filter such as a video camera and a still camera.
[0060] This application claims priority from Japanese Patent Application No. 2003-393978 filed on Nov. 25, 2003, which is hereby incorporated by reference herein. | It is a main object of the present invention to suppress the differences of color ratios of B/G and R/G when the film thicknesses of antireflective films and insulation films vary at a processing process. The present invention is a photoelectric conversion apparatus including a plurality of light receiving portions arranged on a semiconductor substrate, antireflective films formed on the light receiving portions with insulation films put between them, and color filter layers of a plurality of colors formed on the antireflective films, wherein film thicknesses of the insulation films and/or the antireflective films are changed such that changing directions of spectral transmittances at peak wavelengths of color filters on sides of the shortest wavelengths and at peak wavelengths of color filters on sides of the longest wavelengths after transmission of infrared cutting filters may be the same before and after changes. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. application Ser. No. 13/774,671, filed on Feb. 22, 2013 to Douglas E. Loveday, entitled “System and Method for a Hydration Garment.”
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This present invention generally relates to garments having the ability to carry water or other beverages.
[0004] Plastic water bottles are generally disposable and are widely used during both indoor and outdoor exercising activities.
[0005] Previous inventions provide a mechanism for attaching a water bottle to an exerciser in order to facilitate hands-free athletic activity. These devices alleviate the inconvenience associated with exercising while manually carrying a bottle. However, the devices often used a belt, loop, or strap to connect the bottle to the exerciser in a loose or dangling manner. When attached in such ways, water bottles often swing a great deal during athletic activities, making exercising difficult. Further, prior water bottle carriers connect to the exerciser via a belt or carrying mechanism that is often clipped to the exerciser's waistband. These devices may inadvertently and unintentionally become unattached from the user's belt with ease.
[0006] 2. Description of Related Art
[0007] The prior art generally falls into two categories. The first category includes attachable water bottle carriers. The second category includes carrying devices that are not configured for holding water bottles, but are permanently affixed to an article of clothing.
[0008] The first category includes inventions that hold bottles via loops, hooks, and other bottle gripping devices. Some inventions utilize an attachment to a waistband or pocket of a pair of pants (or shortened pants) that secures a bottle by the neck through a loop or cord around the bottle. This invention is not permanently affixed to the pants. Additionally, it is typically located on either side of the wearer, over the hip, and near one of the wearer's side pocket. Other inventions are specifically for hands-free water bottle carrying. These patents utilize a device that clips onto a user's waistband or belt and provides a form-fit grip for grasping water bottles that surround approximately three-fourths of the bottle. These inventions are meant for use on the user's side or hip and also contain a stabilizing grip that surrounds the top of the water bottle. Sometimes the bottle can be attached to the user's side or hip by a keychain; this allows the bottle to dangle. Velcro™ could also be used to stick a holder to the side of a piece of exercise equipment. The water bottle is then placed in the holder that is stuck to the equipment.
[0009] The other category includes clothing with permanent item holders. Some inventions include sewn in internal front pockets for storing firearms, ammunition, handcuffs, or police batons. The invention is typically designed for use by law enforcement officials. Belt loops can also be used that surround the user's waist to stabilize two sewn on, optionally permanent, tool carriers that are attached to a pair of pants and located halfway between the wearer's hip and knee. These inventions are typically for carpentry tools.
[0010] So as to reduce the complexity and length of the Detailed Specification, and to fully establish the state of the art in certain areas of technology, Applicant herein expressly incorporates by reference all of the following materials identified in each numbered paragraph below.
[0011] U.S. Patent Publication 2007/0083984 describes a bottle carrier attached to the pocket, belt, or waistband of a pair of pants that attaches near the cap of a bottle.
[0012] U.S. Patent Publication 2005/0109803 describes a bottle carrier that attaches to a waistband or belt via a keychain and holds a bottle just below the bottle's cap.
[0013] U.S. Pat. No. 6,004,033 describes a water receptacle that can be attached to a piece of exercise equipment through the use of Velcro.
[0014] U.S. Pat. No. 7,058,987 describes a pocket sewn into the front of a pair of trousers that can carry weapons or other equipment. It is designed for use by law enforcement officers.
[0015] U.S. Patent Publication 2008/0216212 describes carpenter pants.
[0016] Applicants believes that the material incorporated above is “non-essential” in accordance with 37 CFR 1.57, because it is referred to for purposes of indicating the background of the invention or illustrating the state of the art. However, if the Examiner believes that any of the above-incorporated material constitutes “essential material” within the meaning of 37 CFR 1.57(c)(1)-(3), applicant(s) will amend the specification to expressly recite the essential material that is incorporated by reference as allowed by the applicable rules.
BRIEF SUMMARY OF THE INVENTION
[0017] The present invention provides among other things a system for a hydration support garment. The hydration support garment can include a lower body garment with a rear exterior surface and a receptacle coupled to the rear exterior surface and configured to house a first beverage container. The receptacle comprises a first strap and a receptacle strap perpendicularly intersecting one another. The hydration support garment can also include a securing strap coupled to the rear exterior surface, proximal to an open end of the receptacle, and configured to stabilize the first beverage container against the lower body garment when the first beverage container is housed within the receptacle. The hydration support garment can further include a clip coupled to the lower body garment and configured to clip to a second beverage container, and a second strap coupled to the rear exterior surface and configured to stabilize the second beverage container against the lower body garment when the second beverage container is clipped onto the clip.
[0018] In another embodiment, the hydration support garment may also be comprised of a lower body garment with a rear exterior surface, a receptacle coupled to the rear exterior surface and configured to house a first beverage container, where the receptacle comprises a first strap and a receptacle strap perpendicularly intersecting one another, and a securing strap coupled to the rear exterior surface proximal to an open end of the receptacle and configured to stabilize the first beverage container against the lower body garment when the first beverage container is housed within the receptacle. The hydration support garment may also include a clip coupled to the lower body garment and configured to clip to a second beverage container, and a Velcro patch coupled to the rear exterior surface and configured to receive a mating Velcro patch on the second beverage container to stabilize the second beverage container against the lower body garment when the second beverage container is clipped onto the clip.
[0019] In another embodiment, the hydration support garment may be comprised of a lower body garment with a rear exterior surface, a receptacle coupled to the rear exterior surface at an anchor point and configured to house a beverage container, where the receptacle comprises a first strap and a receptacle strap perpendicularly intersecting one another, and a securing strap coupled to the rear exterior surface proximal to an open end of the receptacle and configured to stabilize the beverage container against the lower body garment when the beverage container is housed within the receptacle. The hydration support garment can also include a compression strap coupled to the rear exterior surface at the anchor point and configured to wrap around one of a wearer's lower torso and a wearer's thigh to stabilize the beverage container against the wearer when the beverage container is housed within the receptacle.
[0020] Aspects and applications of the invention presented here are described below in the drawings and detailed description of the invention. Unless specifically noted, it is intended that the words and phrases in the specification and the claims be given their plain, ordinary, and accustomed meaning to those of ordinary skill in the applicable arts. The inventors are fully aware that they can be their own lexicographers if desired. The inventors expressly elect, as their own lexicographers, to use only the plain and ordinary meaning of terms in the specification and claims unless they clearly state otherwise and then further, expressly set forth the “special” definition of that term and explain how it differs from the plain and ordinary meaning. Absent such clear statements of intent to apply a “special” definition, it is the inventors' intent and desire that the simple, plain and ordinary meaning to the terms be applied to the interpretation of the specification and claims.
[0021] The inventors are also aware of the normal precepts of English grammar. Thus, if a noun, term, or phrase is intended to be further characterized, specified, or narrowed in some way, then such noun, term, or phrase will expressly include additional adjectives, descriptive terms, or other modifiers in accordance with the normal precepts of English grammar. Absent the use of such adjectives, descriptive terms, or modifiers, it is the intent that such nouns, terms, or phrases be given their plain, and ordinary English meaning to those skilled in the applicable arts as set forth above.
[0022] Further, the inventors are fully informed of the standards and application of the special provisions of 35 U.S.C. §112,916. Thus, the use of the words “function,” “means” or “step” in the Detailed Description or Description of the Drawings or claims is not intended to somehow indicate a desire to invoke the special provisions of 35 U.S.C. §112,916, to define the invention. To the contrary, if the provisions of 35 U.S.C. §112,916 are sought to be invoked to define the inventions, the claims will specifically and expressly state the exact phrases “means for” or “step for, and will also recite the word “function” (i.e., will state “means for performing the function of [insert function]”), without also reciting in such phrases any structure, material or act in support of the function. Thus, even when the claims recite a “means for performing the function of . . . ” or “step for performing the function of . . . ,” if the claims also recite any structure, material or acts in support of that means or step, or that perform the recited function, then it is the clear intention of the inventors not to invoke the provisions of 35 U.S.C. §112,916. Moreover, even if the provisions of 35 U.S.C. §112,916 are invoked to define the claimed inventions, it is intended that the inventions not be limited only to the specific structure, material or acts that are described in the preferred embodiments, but in addition, include any and all structures, materials or acts that perform the claimed function as described in alternative embodiments or forms of the invention, or that are well known present or later-developed, equivalent structures, material or acts for performing the claimed function.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0023] A more complete understanding of the present invention may be derived by referring to the detailed description when considered in connection with the following illustrative figures. In the figures, like reference numbers refer to like elements or acts throughout the figures.
[0024] FIG. 1 illustrates a rear view of a hydration garment, according to one embodiment of the invention, including an angled beverage container receptacle.
[0025] FIG. 2 illustrates a rear view of a hydration garment, according to one embodiment of the invention, including a perpendicular beverage container receptacle.
[0026] FIG. 3 illustrates a rear view of a hydration garment, according to one embodiment of the invention, configured to hold two beverage containers.
[0027] FIG. 4 illustrates a rear view of a hydration garment, according to one embodiment of the invention, including a zippered receptacle.
[0028] FIG. 5 illustrates a rear perspective view of a hydration garment, according to one embodiment of the invention, including a tongue and groove holster.
[0029] FIG. 6 illustrates a rear perspective view of a hydration garment, according to one embodiment of the invention, including a snap receptacle.
[0030] FIG. 7 illustrates a rear view of a hydration garment, according to one embodiment of the invention, including first and second beverage container holders.
[0031] FIG. 8 illustrates a rear view of a hydration garment, according to one embodiment of the invention, including a compression strap.
[0032] Elements and acts in the figures are illustrated for simplicity and have not necessarily been rendered according to any particular sequence or embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0033] In the following description, and for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the various aspects of the invention. It will be understood, however, by those skilled in the relevant arts, that the present invention may be practiced without these specific details. In other instances, known structures and devices are shown or discussed more generally in order to avoid obscuring the invention. In many cases, a description of the operation is sufficient to enable one to implement the various forms of the invention. It should be noted that there are many different and alternative configurations, devices and technologies to which the disclosed inventions may be applied. The full scope of the inventions is not limited to the examples that are described below.
[0034] FIG. 1 shows one embodiment of the invention. In it, a neoprene patch 200 may be sewn onto the back of a pair of commercially available or other athletic shorts 100 . Pants or skirts can also be used in lieu of athletic shorts 100 . The patch 200 may contain a substantially cylindrical receptacle 201 that may be sewn on the rear of the athletic pants, shorts, a skirt or other garment such that the substantially cylindrical receptacle may extend away from the user's body. The patch 200 may be located on the posterior of the athletic shorts 100 or other garment. The substantially cylindrical receptacle 201 may be comprised of a first open end 207 and a second open end 208 . The substantially cylindrical receptacle 201 may also include a stabilizing strap 202 that is coupled to one exterior side of the substantially cylindrical receptacle 201 , runs across second open end 208 of the receptacle, and attaches to the opposite exterior side of the second open end 208 of the substantially cylindrical receptacle. The mechanism of attachment may include a hook and loop fastener, such as Velcro™ or a clipping device 203 or another similar mechanism. The first open end 207 may be located distally from the end that the stabilizing strap 202 runs across. Additionally, the invention may comprise an elastic securing strap 204 that is also sewn to the neoprene attachment. The elastic securing strap 204 is located above the first open end 207 of the substantially cylindrical receptacle 201 and is used to secure the water bottle when it is placed in the substantially cylindrical receptacle 201 . The elastic securing strap 204 may also be made of plastic or any other similar material. This application of the invention may also optionally comprise a pocket 205 sewn into the neoprene patch 200 . The pocket 205 can store a cellular telephone, energy gel, a compass, or any other device the user wants. The invention may also comprise a key-storing accessory 206 that may be comprised of wire, magnets, a hook, or a loop, or both. This accessory 206 may be used to store house or car keys. The cylindrical receptacle 201 , elastic securing strap 202 , elastic strap 204 , pocket 205 , and accessory 206 may all be angled with respect to the neoprene belt loop 101 .
[0035] FIG. 2 shows an alternative embodiment to the invention. As shown, the cylindrical receptacle 201 , stabilizing strap 202 , elastic securing strap 204 , pocket 205 , and accessory 206 may be coupled to the neoprene patch 200 perpendicularly with respect to the neoprene belt loop 101 . This embodiment still includes a first open end 207 and a second open end 208 . This embodiment may be more comfortable than FIG. 1 's embodiment to users with certain body shapes or running styles.
[0036] FIG. 3 shows an alternative embodiment to the invention. In FIG. 3 , there is no pocket for a phone or other items, nor is there an attachment for keys. Instead, there may be at least two water bottle holders coupled to the neoprene patch 900 . FIG. 3 shows a first water bottle holder has both a first open end 907 and a second open end 909 . The first water bottle holder may be comprised of a first cylindrical receptacle 901 , a first stabilizing strap 903 , and a first elastic securing strap 905 . FIG. 3 also shows a second water bottle holder that may also have both a first open end 908 and a second open end 910 . The second water bottle holder may be comprised of a second cylindrical receptacle 902 , a second stabilizing strap 904 , and a second elastic securing strap 906 . This embodiment is particularly helpful if the user plans on going on extended exercise excursions.
[0037] FIG. 4 shows an alternative embodiment to the invention. The invention still includes an elastic securing strap 204 , a pocket 205 , and an accessory for keys 206 . It is still designed to secure a water bottle to a pair of athletic shorts. However, in this embodiment, the cylindrical receptacle 307 may be comprised of both an open end 207 and a base 308 . The base 308 is made of mesh, or other similarly supportive materials. The open end 207 is located distally from the base 308 . The receptacle may be attached to the neoprene pouch by zippers 309 .
[0038] FIGS. 5 and 6 show two other alternative embodiments to the invention. Both embodiments may include an elastic securing strap 204 , a pocket 205 , and an accessory for keys 206 . In FIG. 5 's embodiment, however, the mechanism by which the cylindrical receptacle 201 may connect to the neoprene patch 200 is by a detachable tongue 608 and groove 607 holster. The one or more tongues 608 may be attached to the cylindrical receptacle 201 by a hook and loop fastener such as Velcro™ or a similar mechanism and allow for the cylindrical receptacle 201 to slide into the grooves 607 , which form a track, and firmly attach to the neoprene patch 200 . The tongues 608 may slide into the groove 607 of the holster either vertically, horizontally, or at an angle with respect to the user. The tongue and groove holster may work by allowing the tongue 608 to be shaped such that it will slide into the groove 607 and create a secured placement of the cylindrical receptacle 201 within the holster when the tongue 608 reaches an end of the groove 607 along the track. The tongues 608 may couple to the groove 607 holster either by a specially shaped piece at the end of the holster's track, magnets, a tying mechanism, or by any other appropriate fastener. The end of the holster's track may be placed so that it is closer to the waistband of the shorts, pants or skirt than it is to the bottom of the garment, or so it is closer to the bottom of the garment than it is to the garment's waistband. The tongues 608 and grooves 607 may be made out of plastic, wood, lightweight metals, or any other similar materials.
[0039] FIG. 6 also shows an embodiment by which the mechanism of attaching the cylindrical receptacle 201 to the neoprene patch 200 may differ. Instead of using a detachable tongue 608 and groove 607 , as displayed in FIG. 5 , a set of detachable snaps 707 can be used. The snaps 707 may be attached to the outside of the cylindrical receptacle and have corresponding clasps located below snaps 707 that allow the cylindrical receptacle to be buttoned, or “snapped,” securely into the neoprene patch 200 .
[0040] FIG. 7 illustrates a lower body garment 1000 , such as shorts, according to another embodiment of the invention. The shorts 1000 can include a first holder assembly 1001 , a second holder assembly 1002 , and one or more pockets 1003 coupled to a rear or posterior exterior surface of the shorts 1000 . The shorts 1000 can also include an external waistband 1006 and loops 1007 around the external waistband 1006 . As shown in FIG. 7 , the shorts 1000 can be configured to hold multiple beverage containers. For example, the first holder assembly 1001 can house a first beverage container 1004 , such as a water bottle, and the second holder assembly 1002 can house a second beverage container 1005 , such as a water bottle or, more specifically, an empty water bottle. The shorts 1000 can be athletic shorts, compression shorts, or “2-in-1” combination compression and athletic shorts. In some embodiments where the shorts 1000 are compression shorts or 2-in-1 shorts, the external waistband 1006 may not be necessary. In addition, in alternative embodiments, the shorts 1000 can be a skirt or pants.
[0041] In some embodiments, the external waistband 1006 can be permanently coupled to the shorts 1000 in a way that allows a wearer to tighten the shorts against the wearer's waist using the external waistband 1006 and also in a way that allows components such as clips to be clipped around the external waistband 1006 . The external waistband 1006 can be tightened and secured at the front of the shorts 1000 by a tie or buckle (not shown). In one embodiment, the external waistband 1006 can be internal within the waistband of the shorts 1000 , with only the tie or buckle exposed to permit the wearer to tighten the shorts 1000 . In addition, in some embodiments, the external waistband 1006 can be made of nylon and the loops 1007 can be made of neoprene or can be nylon straps.
[0042] As shown in FIG. 7 , the first holder assembly 1001 is configured to hold the first beverage container 1004 and can include a cylindrical receptacle 1008 with a receptacle strap 1009 and a perpendicular stabilizing strap 1010 , and a securing strap 1011 positioned proximal to an open end of the cylindrical receptacle 1008 . The receptacle strap 1009 , the stabilizing strap 1010 , and the securing strap 1011 can be similar to the receptacle components described above with respect to FIGS. 1 and 2 . More specifically, the receptacle strap 1009 and the stabilizing strap 1010 can secure a lower end of the first beverage container 1006 against the shorts 1000 , and the securing strap 1011 can secure an upper end of the first beverage container 1004 against the shorts 1000 .
[0043] According to one embodiment, the receptacle strap 1009 is coupled to the shorts 1000 via a neoprene patch. The stabilizing strap 1010 is coupled on one end to the receptacle strap 1009 , by sewing, snaps, Velcro™ or other suitable connections, and on the other end to a neoprene patch coupled to the shorts 1000 . Finally, the securing strap 1011 is coupled to the external waistband 1006 or one or more loops 1007 . In other embodiments, the receptacle strap 1009 , the stabilizing strap 1010 , and the securing strap 1011 can be coupled to the shorts 1000 in a variety of ways through sewing, Velcro™, snaps, or other suitable coupling methods. For example, each of the receptacle strap 1009 , the stabilizing strap 1010 , and/or the securing strap 1011 can be coupled directly to the shorts 1000 , thus removing the need for the large neoprene patch 200 of FIGS. 1-6 . In another example, one or more smaller neoprene patches (not shown) can be coupled to the shorts 1000 and the receptacle strap 1009 , the stabilizing strap 1010 , and/or the securing strap 1011 can be coupled to the neoprene patches. In yet another example, the receptacle strap 1009 , the stabilizing strap 1010 , and/or the securing strap 1011 can be coupled to nylon straps, which are then coupled to the shorts 1000 . The nylon straps may permit less stretch than the neoprene patches and, as a result, permit less bouncing of the first beverage container 1004 against the shorts 1000 when the wearer is, for example, running.
[0044] As shown in FIG. 7 , the pocket 1003 can be made of neoprene and can be coupled to a neoprene patch or directly to the rear exterior surface of the shorts 1000 . The pocket 1003 can store a cellular telephone, energy gel, a compass, or any other device the wearer wants. In some embodiments, the pocket 1003 may be comprised of wire, magnets, a hook, or a loop, or both in order to securely house a key. While FIG. 7 shows the pocket 1003 in a central position with respect to the rear or posterior of the shorts 1000 and the first holder assembly 1001 lateral to the pocket 1003 , these elements may be switched so that the first holder assembly 1001 is in a central position while the pocket 1003 is lateral to the assembly 1001 . In addition, in some embodiments, as shown in FIG. 7 , the pocket 1003 and the first holder assembly 1001 can be positioned perpendicular to the external waistband 1006 . In other embodiments, the pocket 1003 and/or the first holder assembly 1001 can be angled with respect to the external waistband 1006 .
[0045] FIG. 8 illustrates another embodiment of the invention, which can be incorporated into the embodiment of FIG. 7 . As shown in FIG. 8 , the receptacle strap 1009 is attached to the shorts 1000 at anchor points 1012 and 1013 . A compression strap 1014 can be coupled to the shorts 1000 at the anchor points 1012 , 1013 and configured to wrap around a wearer's thigh or torso. The compression strap 1014 can serve to press the shorts 1000 against the wearer's body at the anchor points 1012 and 1013 in order to prevent the first beverage container 1004 from bouncing against the wearer when the wearer is, for example, running, while not obstructing the wearer's leg movements.
[0046] In some embodiments, the compression strap 1014 is not coupled to the shorts 1000 directly at the anchor points 1012 and 1013 . Rather, more generally, the compression strap 1014 can be coupled to the shorts 1000 at a different anchor point proximal to the cylindrical receptacle 1008 and between about one inch and about two inches below the external waistband 1006 or waistband of the shorts 1000 . In addition, in some embodiments, the compression strap 1014 can be elastic and can be about two inches in width. The compression strap 1014 can also be used with the embodiments described above with respect to FIGS. 1-6 . Furthermore, in some embodiments, compression shorts 1000 , instead of baggier athletic shorts, may take the place of the compression strap 1014 .
[0047] Referring back to FIG. 7 , the second holder assembly 1002 is configured to hold the second beverage container 1005 and can include a clip 1015 , such as a carabiner clip, and a securing strap 1016 . The clip 1015 can be permanently coupled to the shorts 1000 or can clip around the external waistband 1006 or the loops 1007 . The clip 1015 can also clip to the second beverage container 1005 . The securing strap 1016 can be coupled to the rear exterior surface of the shorts 1000 and can be configured to stabilize a lower portion the second beverage container 1005 against the shorts 1000 or, more specifically, against the wearer. The securing strap 1016 can serve to prevent the second beverage container 1005 from dangling freely when clipped to the clip 1015 .
[0048] In addition, the securing strap 1016 can be an elastic strap similar to the securing strap 1011 and/or the receptacle strap 1009 of the first holder assembly 1001 . For example, the securing strap 1016 can be coupled to the shorts 1000 by nylon straps at anchor points 1017 , 1018 . In some embodiments, another compression strap (not shown) can be coupled to the shorts 1000 at the anchor points 1017 , 1018 and configured to wrap around the wearer's thigh or lower torso in order to further prevent the second beverage container 1005 from bouncing when the wearer is, for example, running. In addition, the securing strap 1016 can be positioned perpendicular to the external waistband 1006 or angled with respect to the external waistband 1006 .
[0049] In some embodiments, as shown in FIG. 8 , the second holder assembly 1002 can include the clip 1015 and, rather than the securing strap 1016 , a Velcro™ patch 1019 . The patch 1019 can be coupled to the shorts 1000 below the external waistband 1006 . The second beverage container 1005 can include a mating Velcro™ patch 1020 so that, when the second beverage container 1005 is clipped to the clip 1015 , the second beverage container 1005 can be secured to the patch 1019 via the patch 1020 in order to secure the container 1005 against the shorts 1000 .
[0050] The embodiments described above generally provide a lower body garment to hold one or more beverage containers, such as water bottles, near the backside of the wearer and secure the beverage containers against a wearer's body to prevent substantial bouncing or flopping of the beverage containers while the wearer is, for example, running. Because the beverage container holders are integrated into the lower body garment, no additional items, such as additional belts or packs, may be necessary to hold and secure the beverage containers to the wearer. In addition, because the beverage container holders include cylindrical receptacles and/or elastic straps, the garment can be used with conventional cylindrical water bottles or other cylindrical water bottles of variable circumferences. | This invention is a hydration support garment including a pair of athletic pants or shorts. The hydration support garment is comprised of a cylindrical receptacle sewn onto the rear of the aforementioned athletic apparel that is configured to house a water bottle. In some applications of the invention, the receptacle includes a receptacle strap and a perpendicular stabilizing strap. Some implementations further include an elastic strap that secures the top of the water bottle. Finally, the invention may also contain a second water bottle holder including a clip and another elastic strap or Velcro™ patches. The invention is designed to provide hands-free access to a hydration source in such a way to allow the user of the invention to exercise without manually carrying a water bottle when hydration is unnecessary. | 0 |
This invention was made with government support under grant number CA-53340 awarded by the Department of Health and Human Services.
FIELD OF THE INVENTION
The present invention relates to 2-aminocarbonyl-1,2-bis(methylsulfonyl)-1-(substituted)hydrazines exhibiting antitumor activity in mammals. Methods of treating neoplasia, especially including solid tumors are additional aspects of the present invention.
BACKGROUND OF THE INVENTION
The search for compounds exhibiting enhanced anti-neoplastic activity has focused some attention on nitrosourea compounds such as 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and related agents. Several N-(2-chloroethyl)-N-nitrosoureas (CNUs) have been evaluated clinically and have been shown to possess significant antineoplastic activity against brain tumors, colon cancer and lymphomas (See, DeVita, et al., Cancer Res. 1965, 25, 1876-1881; Nissen, et al., Cancer 1979, 43, 31-40). Characterization of the decomposition products of the clinically used CNUs, such as BCNU and 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU), has resulted in the identification of several reactive products, including chloroethylating, carbamoylating and hydroxyethylating species (See, for example, Montgomery, et al., J. Med. Chem. 1967, 10, 668-674; Montgomery, et al., J. Med. Chem. 1975, 18, 568-571; Weinkam and Lin, J. Med. Chem. 1979, 22, 1193-1198; and Brundrett, R. B., J. Med. Chem. 1980, 23, 1245-1247).
The antitumor activity of the CNUs has been suggested to result from chloroethylation and subsequent crosslinking of DNA (See Kohn, K. W. in Recent Results in Cancer Research (Eds. Carter, S. K., Sakurai, Y., and Umezawa, H.), vol. 76, p. 141, Springer, Berlin (1981)). In support of this view is the observation that many chloroethylating agents with no carbamoylating activity (e.g., clomesone, as discussed by Shealy, et al., J. Med. Chem. 1984, 27, 664-670) possess excellent antineoplastic activity. In addition, replacement of the chloro group in CNUs by a hydroxyl group has resulted in a considerable decrease in antineoplastic activity (Montgomery, J. A., personal communication; cited by Gibson, et al., Cancer Res. 1986, 46, 553-557). Furthermore, there is some evidence that hydroxyethylation of DNA is a carcinogenic and/or mutagenic event (Pelfrene, et al., J. Natl. Cancer Inst. 1976, 56, 445-446; and Swenson, et al., J. Natl. Cancer Inst. 1979, 63, 1469-1473).
While hydroxyethylation seems to have no salutary effect on the antineoplastic activity of the CNUs, there appears to be some uncertainty regarding the role played by the carbamoylating species (i.e., the isocyanate). The isocyanate generated from the CNUs reacts with thiol and amine functionalities on proteins and inhibits DNA polymerase (Baril, et al., Cancer Res. 1975, 35, 1-5.), the repair of DNA strand breaks (Kann, et al., Cancer Res. 1974, 34, 398-402), and RNA synthesis and processing (Kann, et al., Cancer Res. 1974, 34, 1982-1988). In addition, BCNU has been shown to inhibit glutathione reductase, ribonucleotide reductase and thioredoxin reductase (Schallreuter, et al., Biochim. Biophys. Acta 1990, 1054, 14-20). Although it is believed by many that some of these same properties contribute to the toxic side effects of CNUs (Colvin, et al., Biochem. Pharmacol. 1976, 25, 695-699; Wheeler, et al., Cancer Res. 1974, 34, 194-200; and Panasci, et al., Cancer Res. 1977, 37, 2615-2618), it is entirely possible, as speculated by Gibson and Hickman (Gibson and Hickman, Biochem. Pharmacol. 1982, 31, 2795-2800) in their study of the effects of BCNU on the TLX tumor in mice, that intracellular release of isocyanates plays a role in modulating the biological activity of the CNUs against some specific tumor types. Caracemide, an investigational antitumor agent developed by the Dow Chemical Company (Newman and Farquhar, Invest. New Drugs 1987, 5, 267-271 and Slatter, et al., Chem. Res. Toxicol. 1993, 6, 335-340) is thought to act as a latent form of methyl isocyanate. This agent was shown to be active in a number of National Cancer Institute tumor models, including the mammary MX-1 and colon CX-1 human tumor xenografts implanted in the subrenal capsules of athymic mice (Clinical brochure "Caracemide NSC 253272", Division of Cancer Treatment, National Cancer Institute, 1983).
The hydroxyethylating species generated from the CNUs, 2-hydroxyethyldiazohydroxide, is thought to be formed from 4,5-dihydro-1,2,3-oxadiazole which, in turn, has been hypothesized to be the result of an internal cyclization reaction involving the N-nitroso group (Brundrett, R. B., J. Med. Chem. 1980, 23, 1245-1247). The N-nitroso group is also involved in the enzymatic inactivation of the CNUs. For example, BCNU can be inactivated by denitrosation by liver microsomal enzymes in an NADPH-dependent reaction, with the formation of 1,3-bis(2-chloroethyl)urea (Hill, et al., Cancer Res. 1975, 35, 296-301 and Lin and Weinkam, J. Med. Chem. 1981, 24, 761-763). The denitrosation reaction is catalyzed by NADPH:cytochrome P450 reductase in the case of CCNU (Potter and Reed, Arch. Biochem. Biophys. 1982, 216, 158-169 and Potter and Reed, J. Biol. Chem. 1983, 258, 6906-6911). BCNU has also been shown to undergo glutathione-dependent denitrosation catalyzed by rat (Smith, et al., Cancer Res. 1989, 49, 2621-2625) and human (Berhane, et al., Cancer Res. 1993, 53, 4257-4261) glutathione S-transferase mu isoenzymes.
Since tumor cell-catalyzed denitrosation could conceivably be a potential mechanism of resistance to the CNUs, our aim was to synthesize a series of compounds that (a) were capable of generating a chloroethylating or methylating species; (b) were capable of forming a carbamoylating species; (c) were devoid of hydroxyethylating activity; and (d) were free from structural features that would make them highly prone to metabolic inactivation.
We believed that 2-aminocarbonyl-1,2-bis(methylsulfonyl)-1-(substituted)hydrazines (I) might satisfy the above conditions for the following reasons:
(a) Base-catalyzed elimination of compounds I would result in the formation of a chloroethylating or methylating species and a carbamoylating agent as shown below. ##STR1## (b) At least three classes of prodrugs of species II, i.e., 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazine, 1-(2-chloroethyl)-1,2,2-tris(methylsulfonyl)hydrazine (Shyam, et al., J. Med. Chem. 1990, 33, 2259-2264), and 1-acyl-1,2-bis(methylsulfonyl)-2-(2-chloroethyl)hydrazine (Shyam, et al., J. Med. Chem. 1993, 36, 3496-3502), with potent antitumor activity, have been identified.
(c) The formation of a 4,5-dihydro-1,2,3-oxadiazole intermediate may be prevented by the absence of an N-nitroso moiety. This, in turn, may prevent the formation of a 2-hydroxyethylating agent. The absence of an N-nitroso group may also make the compounds less prone to metabolic inactivation.
OBJECTS OF THE INVENTION
It is an object of the invention to provide effective antineoplastic agents effective for treating numerous cancerous conditions, including solid tumors in animals and humans.
It is another object of the invention to provide antineoplastic agents which are capable of generating a car- bamoylating and chloroethylating chemical species.
It is yet a further object of the invention to provide effective antineoplastic agents which are less prone to metabolic inactivation than compounds of related structure.
It is an additional object of the invention to provide pharmaceutical compositions based upon the use of these novel antineoplastic agents.
It is still another object of the invention to provide methods of treating neoplasia, including solid tumors, in animals and humans.
These and/or other objects of the invention may be readily gleaned from the description of the invention which follows.
SUMMARY OF THE INVENTION
The present invention relates to 2-aminocarbonyl-1,2-bis(methylsulfonyl)-1-(substituted)hydrazine compounds of the formula:
CH.sub.3 SO.sub.2 N(Y)N(CONHR)SO.sub.2 CH.sub.3
where
Y is --CH 3 or --CH 2 CH 2 Cl, and
R is C 1 -C 7 alkyl, cyclohexyl, methylcyclohexyl, --CH 2 CH═CH 2 , --CH 2 CH 2 Cl, --CH 2 CH 2 CH 2 Cl, --CH 2 COOC 2 H 5 , --CH(CH 3 )COOC 2 H 5 or --CH(CH 2 C 6 H 5 )COOC 2 H 5 .
In preferred compounds according to the present invention, Y is --CH 2 CH 2 Cl and R is --CH 2 CH 2 Cl, --CH 2 CH═CH 2 or --CH 3 . R is most preferably --CH 2 CH 2 Cl or --CH 3 . The C 1 -C 7 alkyl substituent is preferably selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl and substituted hexyl. The compounds according to the present invention are produced by synthetic methods which are readily known to those of ordinary skill in the art and include the disclosed chemical synthetic methods.
The present invention also relates to pharmaceutical compositions comprising an antineoplastic effective amount of a 2-aminocarbonyl-1,2-bis(methylsulfonyl)-1-(substituted)hydrazine compound as set forth above. These pharmaceutical compositions preferably also include a pharmaceutically acceptable additive, carrier or excipient.
The present invention also relates to a method for treating neoplasia in mammals comprising administering an antineoplastic effective amount of 2-aminocarbonyl-1,2-bis(methylsulfonyl)-1-(substituted)hydrazine compound to a patient suffering from cancer. The treatment of solid malignant tumors comprising administering to a patient an antitumor effective amount of one or more of these agents is a preferred embodiment of the present invention. The treatment of leukemias, lung carcinomas, melanoma, reticulum cell sarcoma, among various other related disease states may also be effected using the compounds of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The term "neoplasia" is used throughout the specification to refer to the pathological process that results in the formation and growth of a cancerous or malignant neoplasm, i.e., abnormal tissue that grows by cellular proliferation, often more rapidly than normal and continues to grow after the stimuli that initiated the new growth cease. Malignant neoplasms show partial or complete lack of structural organization and functional coordination with the normal tissue and most invade surrounding tissues, metastasize to several sites, and are likely to recur after attempted removal and to cause the death of the patient unless adequately treated. As used herein, the term neoplasia is used to describe all cancerous disease states and embraces or encompasses the pathological process associated with malignant hematogenous, ascitic and solid tumors.
The term antineoplastic effective amount is used throughout the specification to describe an amount of the present compounds which is used to treat a patient suffering from a cancerous tumor to prevent the further growth of the neoplasms, bring that growth under control and preferably, produce a remission of the tumor.
The term "therapeutically effective amount" is used throughout the specification to describe that amount of the compound according to the present invention which is administered to a mammalian patient, especially including a human patient, suffering from cancer, to reduce or inhibit the growth or spread of the hematogenous, ascitic or solid tumor. Preferably, the compounds according to the present invention will result in a remission of the malignant hematogenous, ascitic or solid tumor. In the case of solid tumors, the compounds according to the present invention will inhibit the further growth of the tumor tissue and shrink the existing tumor.
The present invention is directed to 2-aminocarbonyl-1,2-bis(methylsulfonyl)-1-(substituted)hydrazine compounds of the formula:
CH.sub.3 SO.sub.2 N(Y)N(CONHR)SO.sub.2 CH.sub.3
where
Y is --CH 3 or --CH 2 CH 2 Cl; and
R is C 1 -C 7 alkyl, cyclohexyl, methylcyclohexyl, --CH 2 CH═CH 2 , --CH 2 CH 2 Cl, --CH 2 CH 2 CH 2 Cl, --CH 2 COOC 2 H 5 , --CH(CH 3 )COOC 2 H 5 or --CH(CH 2 C 6 H 5 )COOC 2 H 5 .
In preferred compounds according to the present invention, Y is --CH 2 CH 2 Cl and R is --CH 2 CH 2 Cl, --CH 2 CH═CH 2 , or --CH 3 . R is most preferably --CH 2 CH 2 Cl or --CH 3 . Where R is C 1 -C 7 alkyl, R is selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl or substituted hexyl.
These compounds, which contain a 2-aminocarbonyl group, exhibit enhanced activity against a broad spectrum of neoplastic disease states, including, for example, numerous solid tumors. In in vivo screening tests, these agents have exhibited broad spectrum activity against a wide range of neoplastic disease states. In one case, where R is CH 2 CH 2 Cl, this compound exhibited unexpectedly greater antineoplastic activity than mitomycin C or cyclophosphamide, among the most effective commercial antineoplastic alkylating agents.
The present compounds represent prodrug forms of intermediates which are believed to exhibit their activity through chloroethylation, methylation and/or carbamoylation mechanisms.
The compounds according to the present invention are primarily useful for their antineoplastic activity, including their activity against solid tumors. In addition, these compositions may also find use as intermediates in the chemical synthesis of other useful antineoplastic agents which are, in turn, useful as therapeutic agents or for other purposes.
Compounds according to the present invention are synthesized by the adaptation of techniques which are well known in the art. 2-Aminocarbonyl-1,2-bis(methylsulfonyl)-1-(substituted)hydrazines (I, Y is --CH 3 or --CH 2 CH 2 Cl ) are synthesized by reacting 1,2-bis(methylsulfonyl)-1-methylhydrazine or 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazine with the appropriate isocyanate (where R is of the indicated structure or a related alkyl structure) in dry acetonitrile in the presence of triethylamine as shown below. The synthesis of the appropriate isocyanate derivative for use in this reaction scheme is well known in the art and uses standard chemical techniques. ##STR2## III. R=--CH 2 CH 2 Cl IV. R=--CH 3
V. R=--CH 2 CH=CH 2
VI. R=--CH 2 CH 2 CH 2 Cl
VII. R=--CH 2 COOC 2 H 5
VIII. R=--CH(CH 3 )COOC 2 H 5
IX. R=--CH(CH 2 C 6 H 5 )COOC 2 H 5
X. R=--C 2 -C 7 alkyl, cyclohexyl or methylcyclohexyl
After synthesis, the residue generally is triturated, washed with dilute acid, dried, triturated again and recrystallized from an appropriate solvent, for example, ethanol or ethanol/petroleum ether. Modification of the disclosed chemical synthetic methods may be readily made by those of ordinary skill in the art in order to provide alternative synthetic pathways to the present compounds.
The present invention also relates to pharmaceutical compositions comprising a therapeutically effective amount of a 2-aminocarbonyl-1,2-bis(methylsulfonyl)-1-(substituted)hydrazine compound as set forth above. A therapeutically effective amount of one or more of these compounds is that amount which may be used to treat patients suffering from cancer such as a malignant tumor. These pharmaceutical compositions preferably also include a pharmaceutically acceptable additive, carrier or excipient. In pharmaceutical compositions according to the present invention which relate to the treatment of malignant solid tumors, those compositions comprise an amount of one or more 2-aminocarbonyl-1,2-bis(methylsulfonyl)-1-(substituted)hydrazine compounds as set forth above effective to inhibit the growth of the treated tumor and, in certain cases, to actually shrink the treated tumor.
One of ordinary skill in the art will recognize that a therapeutically effective amount of the compounds according to the present invention to be used to treat malignant tumors will vary with the disease state or condition to be treated, its severity, the treatment regimen to be employed, the result desired (remission, shrinkage of tumor in combination with surgical techniques or radiation), the type of administration used to deliver the compounds, the pharmacokinetics of the compounds used, as well as the patient (animal or human) treated.
In the pharmaceutical aspect according to the present invention, one or more compounds according to the present invention is formulated preferably in admixture with a pharmaceutically acceptable additive, carrier or excipient. In general, it is preferable to administer the pharmaceutical composition in parenteral-administrable form (preferably, intravenous), but consideration should be given to other formulations administered via intramuscular, transdermal, buccal, subcutaneous, suppository, oral or other route. Of course, one of ordinary skill in the art may modify the formulations within the teachings of the specification to provide numerous formulations for a particular route of administration without rendering the compositions of the present invention unstable or compromising the therapeutic activity.
For example, modifying the present compounds to render them more soluble in water or other vehicle, for example, may be easily accomplished by minor modifications (salt formulation, esterification, etc.) which are well within the ordinary skill in the art. It is also within ordinary skill to modify the route of administration and dosage regimen of a particular compound in order to manage the pharmacokinetics of the present compounds for maximum beneficial effect in the patient to be treated. Sustained and/or controlled release forms of the pharmaceutical compositions are also contemplated by the present invention.
The present compounds are prodrug forms of reactive intermediates. In certain pharmaceutical dosage forms, the present compounds may be modified to other prodrug forms to take advantage of a particular route of administration of the active compounds. One of ordinary skill in the art will recognize how to readily modify the present compounds to alternative prodrug forms to facilitate delivery of active compounds to a targeted site within the patient. The individual of ordinary skill also will take advantage of favorable pharmacokinetic parameters of the prodrug forms, where applicable, in delivering the present compounds to a targeted site within the patient to maximize the intended antineoplastic effect of the compound.
The amount of compound included within the therapeutically active formulations according to the present invention is an effective amount for treating the malignant tumor. In general, a therapeutically effective amount of the compound according to the present invention in dosage form usually ranges from less than about 0.05 mg/kg to about 500 mg/kg of body weight of the patient to be treated, or considerably more, depending upon the compound used, the tumor type to be treated, the ability of the active compound to localize in the tissue to be treated, the route of administration and the pharmacokinetics of the compound in the patient. In the case of treating solid tumors, the compound is preferably administered in amounts ranging from about 0.05 mg/kg to about 250 mg/kg or more at one time. This dosage range generally produces effective blood level concentrations of active compound ranging from about 0.01 to about 500 micrograms per ml of blood in the patient to be treated. The duration of treatment may be for one or more days or may last for several months or considerably longer (years) depending upon the disease state treated.
Administration of the active compound may range from continuous (intravenous drip) to intramuscular, to several oral administrations per day (for example, Q.I.D.) and may include parenteral, including intravenous and intramuscular, oral, topical, subcutaneous, transdermal (which may include a penetration enhancement agent), buccal and suppository administration, among other routes of administration.
To prepare the pharmaceutical compositions according to the present invention, a therapeutically effective amount of one or more of the compounds according to the present invention is preferably intimately admixed with a pharmaceutically acceptable carrier according to conventional pharmaceutical compounding techniques to produce a dose. A carrier may take a wide variety of forms depending on the form of preparation desired for administration, e.g., parenteral or oral.
For parenteral formulations, the carrier may comprise sterile water or aqueous sodium chloride solution in combination with other ingredients which aid dispersion, such as ethanol and other pharmaceutically acceptable solvents, including DMSO, among others. Of course, where solutions are to be used and maintained as sterile, the compositions and carriers must also be sterilized. Injectable suspensions may also be prepared, in which case appropriate liquid carriers, suspending agents and the like may be employed.
In preparing pharmaceutical compositions in oral dosage form, any one or more of the usual pharmaceutical media may be used. Thus, for liquid oral preparations such as suspensions, elixirs and solutions, suitable carriers and additives including water, glycols, oils, alcohols, flavouring agents, preservatives, colouring agents and the like may be used. For solid oral preparations such as powders, tablets, capsules, and for solid preparations such as suppositories, suitable carriers and additives including starches, sugar carriers, such as dextrose, mannitol, lactose and related carriers, diluents, granulating agents, lubricants, binders, disintegrating agents and the like may be used. If desired, the tablets or capsules may be enteric coated or sustained release by standard techniques.
The compounds and compositions according to the present invention are used to treat cancer in mammals, including humans. Generally, to treat malignant tumors, the compositions will be administered in parenteral, preferably intravenous dosage form in amounts ranging from about 25 micrograms up to about 500 mg or more one to four times per day. The present compounds are preferably administered parenterally, but they also may be administered in an alternative manner, for example, orally or even topically or in suppository form.
Compounds according to the present invention may be administered alone or in combination with other agents, especially including other compounds of the present invention. In addition, the administration of one or more compounds according to the present invention with other antineoplastic agents, in combination chemotherapy, such as antimetabolites, etoposide, doxorubicin, taxol, vincristine, cyclophosphamide or mitomycin C, among numerous others, is contemplated by the present invention.
While not being limited by way of theory, it is believed that the compounds according to the present invention primarily induce their therapeutic effect in treating malignant tumors by functioning as combined chloroethylating and carbamoylating agents, without also providing hydroxyethylating activity.
The present invention is now described, purely by way of illustration, in the following examples. It will be understood by one of ordinary skill in the art that these examples are in no way limiting and that variations of detail can be made without departing from the spirit and scope of the present invention.
EXAMPLES
Experimental Section
Synthesis. Melting points were determined in capillary tubes on a Thomas-Hoover melting point apparatus and are uncorrected. 1 H NMR spectra were recorded on a Varian EM-390 spectrometer with tetramethyl silane as an internal standard. Elemental analyses were performed by the Baron Consulting Co., Orange, Conn. and the data were within±0.4% of the theoretical values for the 2-aminocarbonyl-1,2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazines.
Example 1
Synthesis of 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)-2-(2-chloroethyl)aminocarbonylhydrazine (III)
To a stirred solution of 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazine (Shyam, et al.,J. Med. Chem., 1990, 33, 2259-2264) (2.5 g, 0.010 mol) and 2-chloroethyl isocyanate (1.2 g, 0.011 mol) in dry acetonitrile (100 mL) was added triethylamine (1.1 g, 0.011 mol) at room temperature. After an additional 10 min, the reaction mixture was evaporated to dryness in vacuo. The residue was triturated twice with 15 mL quantities of petroleum ether and the petroleum ether layer was discarded each time. The residue was then taken up in ethyl acetate (150 mL) and washed with dilute hydrochloric acid (3×15 mL). The ethyl acetate layer was dried over anhydrous magnesium sulfate and filtered. Upon evaporation of the solvent, a semi-solid residue was obtained which, upon trituration with absolute ethanol, gave a white solid. Recrystallization from ethanol afforded 1.5 g (42.2%) of the title compound: mp 96°-97.5° C.; 1 H NMR (acetone-d6) δ 7.0 (br, 1 H, NH), 3.7-4.2 (m, 4 H, SO 2 NCH 2 CH 2 Cl ), 3.5-3.7 (m, 4H, CONHCH 2 CH 2 Cl), 3.5 and 3.3 (2s, 6 H, 2 CH 3 ). Anal. (C 7 H 15 C 12 N 3 O 5 S 2 ) C, H, N.
Examples 2-7
SYNTHESIS OF 2-AMINOCARBONYL-1,2-BIS(METHYLSULFONYL)-1-(2-CHLOROETHYL)HYDRAZINES
The following compounds were prepared using procedures similar to the one described in example 1 for compound III.
1,2-Bis(methylsulfonyl)-1-(2-chloroethyl)-2-methylaminocarbonylhydrazine (IV) was synthesized according to the method of example 1. Compound IV was recrystallized from ethanol: yield 42.4%; mp 146°-147.5° C.; 1 H NMR (acetone-d6) δ 6.7 (br, 1 H, NH), 3.7-4.2 (m, 4 H, CH 2 CH 2 Cl ), 3.5 and 3.3 (2 s, 6 H, 2 CH 3 ), 2.9 (d, 3 H, NCH 3 ). Anal. (C 6 H 14 ClN 3 O 5 S 2 ) C, H, N.
2-Allylaminocarbonyl-1,2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazine (V) was synthesized according to the method of example 1. Compound V was recrystallized from ethanol: yield 42.2%; mp 105°-106° C.; 1 H NMR (acetone-d6) δ 6.9 (br, 1 H, NH), 5.6-6.1 (m, 1 H, CH═C), 5.4, 5.2 and 5.1 (3 d, 2H, C═CH 2 ), 3.7-4.2 (m, 6 H, NHCH 2 and CH 2 CH 2 Cl), 3.5 and 3.3 (2 s, 6 H, 2 CH 3 ). Anal. (C 8 H 16 ClN 3 O 5 S 2 ) C, H, N.
1,2-Bis(methylsulfonyl)-1-(2-chloroethyl)-2-(3-chloropropyl)aminocarbonylhydrazine (VI) was synthesized according to the method of example 1. Compound VI was recrystallized from ethanol: yield 35.2%; mp 85°-86° C.; 1 H NMR (acetone-d6) δ 6.8 (br, 1 H, NH), 3.7-4.2 (m, 4 H, SO 2 NCH 2 CH 2 Cl ), 3.4-3.8 (m, 6 H, CH 2 CH 2 CH 2 Cl ), 3.5 and 3.3 (2 s, 6 H, 2 CH 3 ). Anal. (C 8 H 17 Cl 2 N 3 O 5 S 2 ) C, H, N.
1,2-Bis(methylsulfonyl)-1-(2-chloroethyl)-2-(ethoxycarbonylmethyl)aminocarbonylhydrazine (VII) was synthesized according to the method of example 1. Compound VII was recrystallized from ethanol: yield 42.2%; mp 121°-122° C.; 1 H NMR (acetone-d6) δ 7.1 (br, 1 H, NH), 3.7-4.4 (m, 8 H, OCH 2 , NHCH 2 and CH 2 CH 2 Cl ), 3.5 and 3.3 (2 s, 6 H, 2 CH 3 ), 1.2 (t, 3 H, CCH 3 ). Anal. (C 9 H 18 ClN 3 O 7 S 2 ) C, H, N.
1,2-Bis(methylsulfonyl)-1-(2-chloroethyl)-2-(1-ethoxycarbonylethyl)aminocarbonylhydrazine (VIII) was synthesized according to the method of example 1. Compound VIII was recrystallized from ethanol: yield 28.0%; mp 111°-112° C.; 1 H NMR (acetone-d6) δ 6.9 (br, 1 H, NH), 3.7-4.6 (m, 7 H, OCH 2 , NHCH and CH 2 CH 2 Cl ), 3.5 and 3.3 (2 s, 6 H, 2 CH 3 ), 1.4 (d, 3 H, CHCH 3 ), 1.2 (t, 3 H, CH 2 CH 3 ). Anal. (C 10 H 20 ClN 3 O 7 S 2 ) C, H, N.
1,2-Bis(methylsulfonyl)-1-(2-chloroethyl)-2-(1-ethoxycarbonyl-2-phenylethyl)aminocarbonylhydrazine (IX) was synthesized according to the method of example 1. Compound IX was recrystallized from ethanol-petroleum ether: yield 12.8%; mp 106°-107° C.; 1 H NMR (acetone-d6) δ 7.1-7.3 (m, 5 H, C 6 H 5 ), 6.8 (br, 1 H, NH), 4.6 (m, 1 H, NHCH), 3.6-4.3 (m, 6 H, OCH 2 and CH 2 CH 2 Cl ), 3.5 (s, 3 H, CH 3 SO 2 ), 3.0-3.3 (s, m, 5 H, CH 2 C 6 H 5 , CH 3 SO 2 ), 1.2 (t, 3 H, CH 2 CH 3 ). Anal. (C 16 H 24 ClN 3 O 7 S 2 ) C, H, N.
2-Aminocarbonyl-1,2-bis(methylsulfonyl)-1-methylhydrazine methylhydrazine compounds containing the same aminocarbonyl substituents are prepared by analogy by following the synthetic protocols described above.
Example 8
Antitumor Activity
Antitumor Activity was tested in several cell lines: L1210 leukemia, B16F10 melanoma, M5076 reticulum cell sarcoma, M109 lung carcinoma and LX-1 lung carcinoma.
Leukemia L1210 Testing
Leukemia L1210 cells were obtained from the Frederick Cancer Research Facility, Division of Cancer Treatment Tumor Repository of the National Cancer Institute, and were maintained by serial passage in tissue culture. Every 8 weeks, tumor cells were injected intraperitoneally into five donor CD 2 F 1 mice 8- to 10- weeks of age and were allowed to grow for 7 days. The peritoneal fluid was withdrawn and the suspension was centrifuged for 5 min at 1600 g. The supernatant was decanted and 10 5 cells/mL were seeded into 10 mL of RPMI 1640 medium supplemented with 10% fetal bovine serum and 1% L-glutamine, and once again maintained in culture. To assay for antineoplastic activity, 0.1 mL of the cell suspension containing 10 5 L1210 leukemia cells was injected ip into each recipient mouse. Test compounds were administered over a wide range of dosage levels, beginning 24 h after tumor implantation, and continued once daily for 6 consecutive days. All drugs were administered ip as a solution in 100% dimethylsulfoxide (DMSO), in a volume not exceeding 0.025 mL. In each experiment, animals were distributed into groups of five mice of comparable weight and maintained throughout the course of the experiment on Purina Laboratory Chow pellets and water adlibitum. Control tumor-bearing animals given comparable volumes of vehicle were included in each experiment. Mice were weighed during the course of the experiments, and the percentage change in body weight from onset to termination of therapy was used as an indication of drug toxicity. Determination of the sensitivity of neoplasms to these agents was based upon the prolongation of survival time afforded by the drug treatments.
Results of L1210 Testing
The tumor-inhibitory properties of compounds III-IX were determined in initial tests by measuring their effects on the survival time of mice bearing the intraperitoneally (ip) implanted L1210 leukemia; the results of these tests are summarized in Table 1, below. With the exception of compound VI, all of the agents synthesized produced "cures" (defined as tumor-free 60 days post-tumor implant) in 100% of mice bearing the L1210 leukemia at one or more of the dosage levels examined following ip administration. It is conceivable that compound VI failed to do so only because it was not evaluated at daily dosage levels greater than 15 mg/kg given for 6 consecutive days. Compound VI did, however, produce a partial cure rate of tumor-bearing mice at the highest dosage level examined. Compounds III and IV appeared to have much better therapeutic potential than the amino acid ester derivatives, i.e., compounds VII, VIII and IX. Thus, the methyl urea derivative (IV) produced a 40% cure rate of tumor-bearing mice at 5 mg/kg administered for 6 consecutive days with no body weight loss. This agent also cured 100% of mice bearing the L1210 leukemia at 10 and 15 mg/kg×6 with less than a 6% loss of body weight. The 2-chloroethyl urea derivative (III), which can be regarded as a structural analog of BCNU, cured 80 to 100% of leukemic mice at 10 to 20 mg/kg×6, although at the highest dose examined, i.e., 20 mg/kg, it appeared to be somewhat toxic, as evidenced by a 10.4% loss in body weight. The allyl urea derivative (V) was also highly efficacious against this tumor, curing 100% of mice receiving a daily dosage of 15 mg/kg given for 6 consecutive days. The amino acid ester derivatives (VII-IX), in general, appeared to be considerably less potent than compounds III-V requiring daily dosage levels in the range of 25 to 100 mg/kg to achieve optimum cure rates, and early deaths of treated mice occurred at higher doses in each case.
TABLE 1______________________________________Effects of 2-Aminocarbonyl-1,2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazines On the Survival Time of MiceBearing the L1210 Leukemia Daily Dose Av.Wt. % 60 DayCompound mg/kg.sup.a Change %.sup.b %T/C.sup.c Survivors______________________________________III 10 -4.7 -- 100 15 -4.0 216 80 20 -10.4 239 80IV 5 +9.9 234 40 10 -5.6 -- 100 15 -2.1 -- 100V 5 -1.6 184 20 10 -2.1 394 40 15 -2.9 -- 100VI 5 -2.8 111 -- 10 -5.6 187 -- 15 -8.8 192 20VII 5 -1.5 151 -- 10 -1.4 202 20 15 -0.5 202 -- 20 -3.7 191 20 25 -0.5 -- 100 50 -2.5 138 80 75 -1.5 119 60 100 -4.0 115 --VIII 5 -2.0 170 -- 10 -1.4 178 20 15 -0.5 185 -- 20 -1.5 227 -- 25 -2.5 239 60 50 -3.3 -- 100 75 -2.5 125 80 100 -2.5 118 --IX 5 -2.5 147 -- 10 -0.5 165 -- 15 -1.9 160 -- 20 -1.9 174 -- 25 -0.9 177 -- 50 -2.0 225 60 100 -2.0 -- 100 150 -5.0 169 20______________________________________ .sup.a Administered ip once daily for six consecutive days, beginning 24 hours after tumor implantation, with 5-10 mice being used per group. .sup.b Average percent change in body weight from onset to termination of therapy. .sup.c %T/C = average survival time of treated/control mice × 100; cures (>60day survivors) are listed separately and are not included in this calculation.
a Administered ip once daily for six consecutive days, beginning 24 hours after tumor implantation, with 5-10 mice being used per group. b Average percent change in body weight from onset to termination of therapy. c % T/C=average survival time of treated/control mice×100; cures (>60-day survivors) are listed separately and are not included in this calculation.
B16F10 Melanoma, M5076 Reticulum Cell Sarcoma, M109 Lung Carcinoma and LX-1 Lung Carcinoma Testing
B16F10 melanoma cells were grown in vitro as monolayers in minimum essential medium with Hank's salts supplemented with 10% fetal bovine serum and 1% 200 mM L-glutamine solution. Solid tumors were produced in C57BL/6 female mice 12- to 14-weeks of age by the intradermal injection in the right flank of each mouse of 0.1 mL of a cell suspension containing 10 6 B16F10 cells/mL from freshly trypsinized cultures. After 10-12 days, animals bearing approximately 100 mm 3 tumors were treated ip with compound III or IV dissolved in 100% DMSO for 6 consecutive days, and tumor volumes were measured on alternate days until reaching 1000 mm 3 .
The M5076 reticulum cell sarcoma was passaged biweekly by sc transfer of tumor fragments into C57BL/6 mice, and the M109 lung carcinoma was similarly passaged in BALB/c mice. The LX-1 human lung carcinoma was passaged sc every two to three weeks in BALB/c-background athymic (nu/nu) mice. For use in these systems, compound III was dissolved in: (a) 100% DMSO and administered by iv injection in a fixed volume of 10 microliters; or (b) DMSO diluted with saline to a final concentration of 10% DMSO and administered iv in a volume of 0.01 milliliter/g of body weight. These different modes of formulation resulted in differences in the optimum effective dose found in the various tumor systems. Mitomycin C and cyclophosphamide were dissolved and administered in saline. BCNU and MeCCNU were dissolved in ethanol and diluted 1:9 (v/v) with water prior to administration.
Five mice per group were employed in experiments with the B16F10 melanoma, and 8 mice per group with the M5076 sarcoma, the M109 carcinoma and the LX-1 carcinoma. A minimum of two dose levels per compound were included in each evaluation and drug therapy was initiated 24 h after tumor implantation for the M5076 sarcoma and M109 carcinoma. In the LX-1 experiment, tumor bearing mice were selected and sorted into treatment and control groups on day 6 post-tumor implant such that all tumor weights ranged from 50-100 mg and median tumor weights per group were reasonably similar. Therapeutic results are presented in terms of: (a) increases in lifespan reflected by the relative median survival time (MST) of treated versus control groups (i.e., %T/C values), and by long-term survivors, and (b) primary tumor growth inhibition (i.e., T-C values) determined by calculating the relative median times for treated (T) and control untreated (C) mice to grow tumors of a 0.5 g size for the LX-1 carcinoma or a 1 g size for the murine neoplasms. Tumor weights were interchangeable with tumor size on the basis of 1 mm 3 =1 mg. The activity criterion for increased lifespan was a T/C of≧125%. The activity criterion for tumor inhibition was a delay in tumor growth consistent with one log 10 cell kill (LCK). The absolute T-C value needed to attain this level of efficacy varied from experiment to experiment and depended upon the tumor volume doubling time of the control mice in each study. Treated mice dying prior to day 10 in the ip M109 experiment, or dying before their tumors achieved 0.5 g for the LX-1 carcinoma or 1 g in size for all other sc tumor models, were considered to have died from drug toxicity. Groups of mice with more than one death due to drug toxicity were not used in the evaluation of antitumor efficacy. Statistical evaluations of data were performed using Gehan's generalized Wilcoxan test (Gehan, Biometrika, 1965, 52, 203-233).
Results of B16F10 Melanoma, M5076 Reticulum Cell Sarcoma, M109 Lung Carcinoma and LX-1 Lung Carcinoma Testing
One of the most active and potent compounds in the series as tested in the L1210 system as described above, compound III, was also evaluated against several other transplanted tumors (Table 2, below). When administered at the highest dose examined, i.e, three ip doses of 50 mg/kg given at 4 day intervals in the ip-implanted M109 lung carcinoma model, this compound produced a %T/C of 267. In the same system, but in a different experiment, the acetyl derivative (X) produced a comparable %T/C of 231 at the highest dosage level examined (60 mg/kg per injection), when the drug was administered ip using the same schedule (Shyam, et al., J. Med. Chem. 1993, 36, 3496-3502).
CH.sub.3 SO.sub.2 N(CH.sub.2 CH.sub.2 Cl )N(COCH.sub.3)SO.sub.2 CH.sub.3X
TABLE 2__________________________________________________________________________Summary of Optimal Antitumor Effects of 1,2-Bis(methylsulfonyl)-1-(2-chloroethyl)-2-(2-chloroethyl)aminocarbonylhydrazine (III)onM109, M5076 and LX-1 TumorsTumor, Treatment Optimal Effective %T/C, (Cures/Total),Site Schedule, Route Dose, mg/kg/injection and/or [T-C, days]__________________________________________________________________________M109, ip q4d × 3; d.1.sup.a ; ip 50 .sup.b,c 267M109, sc q4d × 3; d.1.sup.a ; iv 50.sup.c a).sup.d 115[8.3] q3d × 4; d.1.sup.a ; iv 24[32].sup.c,e b).sup.d 143[9.3] 64.sup.f b).sup.d 145[17.8]M5076, sc q2d × 5; d.1.sup.a ; iv 48.sup.f >157(6/8)LX-1, sc q2d × 5; d.6.sup.a ; iv 40.sup.f [14.5]__________________________________________________________________________ .sup.a Day treatment initiated. .sup.b Highest dose tested. .sup.c Administered in 10% DMSO in saline. .sup.d Each letter (a,b) signifies a different experiment. .sup.e Dose in brackets producing the maximum TC obtained. .sup.f Administered in 100% DMSO.
Compound III was also evaluated against the M109 lung carcinoma implanted subcutaneously (sc). In the initial test using this model, a dose of 50 mg/kg per injection of this compound was administered intravenously (iv) in 10% DMSO in saline every fourth day for a total of three injections. While the maximum %T/C achieved (115) was not considered to be an active result, a meaningful delay in tumor growth (T-C) of 8.3 days was observed under these conditions. Mitomycin C, used as a reference drug, produced a maximum %T/C of 103 and a delay in tumor growth of 10 days (data not shown). A subsequent evaluation of compound III was performed using four different doses on a slightly different schedule, i.e., 24, 32, 48 and 64 mg/kg administered every third day for four total injections, and two vehicles, 10% DMSO in saline and 100% DMSO. When administered in 10% DMSO in saline, compound III produced a maximum %T/C of 143 and a maximum delay in tumor growth of 9.3 days at 24 and 32 mg/kg per injection, respectively; the next higher dose evaluated, 48 mg/kg per injection, was excessively lethal. At the highest level evaluated, 64 mg/kg per injection, made possible by the use of 100% DMSO as the vehicle, compound III achieved a maximum %T/C of 145 and a delay in tumor growth of 17.8 days, without causing any treatment-associated lethalities. The latter antitumor effect was statistically superior (p<0.01) to the best T-C value achieved with this compound in 10% DMSO in saline. Cyclophosphamide and mitomycin C were included as reference drugs in the last experiment. The former compound produced a maximum %T/C of 143 and a delay in tumor growth of 8.8 days, while mitomycin C produced a maximum %T/C of 134 and a T-C value of 9.3 days (data not shown). As reported earlier, compound X achieved a maximum %T/C of 136 and a maximum T-C value of 14.5 days against this tumor (Shyam, et al., J. Med. Chem., 1993, 36, 3496).
Compound III was also evaluated against the M5076 reticulum cell sarcoma implanted sc. When administered iv at a level of 48 mg/kg per injection in 100% DMSO every other day for five days, compound III cured 6 out of 8 mice and consequently, no median time (T-C value) to reach 1 gram size tumors was expressed for this group. Tumor growth in mice receiving only 100% DMSO was indistinguishable from that of untreated control animals. 1-(2-Chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea (MeCCNU) and BCNU were included in this experiment for comparison. The former achieved a maximum %T/C of 128 and a delay in tumor growth of 33.5 days at 16 mg/kg per injection administered iv every fourth day for three total injections, while BCNU, administered iv on the same treatment schedule, produced a %T/C in excess of 157, with 2 out of 8 cures, and a T-C of >62 days (data not shown). Since compound X, a chloroethylating agent with no carbamoylating activity, is much less active than compound III or BCNU against this tumor, it seems probable that the generation of an isocyanate intermediate contributes to the antineoplastic properties of chloroethylating agents against the M5076 sarcoma.
The human lung tumor, LX-1, xenografted sc in athymic mice, was also used to examine the antineoplastic potential of compound III. Treatment was initiated on day 6 post-implant when the median weight of the tumors was approximately 100 mg. A dose of 40 mg/kg per injection of compound III administered iv in 100% DMSO on an every other day schedule for a total of five injections was optimal; this regimen produced a median delay of 14.5 days in the growth of this tumor to a target size of 0.5 g. This level of activity, 1.6 LCK, compared favorably with that obtained with BCNU in the same experiment, which produced a T-C of 11.8 days (1.3 LCK) at the optimum dosage of 20 mg/kg per injection when administered iv every fourth day for a total of three injections.
In addition, both compounds III and IV were evaluated in 100% DMSO against the B16F10 melanoma implanted intradermally (id) in mice (Table III). In an initial experiment, compound IV produced a T-C of 15.5 days at a daily dosage level of 20 mg/kg administered once daily for six consecutive days beginning on day 10 post-implant. In the same experiment, using the same treatment schedule, a growth delay of 11 days was obtained with compound III. In the second experiment, when the daily dose of compound IV was increased to 30 mg/kg, a more substantial growth delay of 25.5 days was achieved, whereas compound III at the same daily dose of 30 mg/kg was less active, with the T-C value obtained being 13.5 days. Thus, the aminocarbonyl component in this class of agents influences the magnitude of the antitumor effects obtained against the B16F10 melanoma.
TABLE 3______________________________________Antitumor Activity of 1,2-Bis(methylsulfonyl)-1-(2-chloroethyl)-2-(2-chloroethyl)aminocarbonylhydrazine (III) and 1,2-Bis(methylsulfonyl)-1-(2-chloroethyl)-2-methyl-aminocarbonylhydrazine (IV) Against sc B16F10 MelanomaCom- Treatment Optimal Effectivepound Schedule, Route Dose, mg/kg/iniection T-C, Days______________________________________III qd × 6; d.10.sup.a ; ip 20.sup.b a).sup.c 11.0 qd × 6; d.12.sup.a ; ip 20.sup.b b).sup.c 5.5 30.sup.b b).sup.c 13.5IV qd × 6; d.10.sup.a ; ip 10.sup.b a).sup.c 5.0 20.sup.b a).sup.c 15.5 qd × 6; d.12.sup.a ; ip 20.sup.b b).sup.c 10.0 30.sup.b b).sup.c 25.5______________________________________ .sup.a Day treatment initiated. .sup.b Administered in 100% DMSO. .sup.c Each letter (a,b) signifies a different experiment.
Summary
In summary, 2-aminocarbonyl-1,2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazines were highly active against the L1210 leukemia in mice. A representative agent of this class, compound III, was found to have substantial activity in several more stringent distal site tumor models, that unexpectedly was better than or equal to some of the best clinically active alkylating agents used for comparison in these assays. Furthermore, a comparison of compounds III and IV against the B16F10 melanoma demonstrated that the aminocarbonyl substituent influenced the degree of antineoplastic activity attainable.
It is to be understood by those skilled in the art that the foregoing description and examples are illustrative of practicing the present invention, but are in no way limiting. Variations of the detail presented herein may be made without departing from the spirit and scope of the present invention as defined by the following claims. | The present invention relates to novel 2-aminocarbonyl-1,2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazines and 2-aminocarbonyl-1,2-bis(methylsulfonyl)-1-methylhydrazines, and their use to treat malignant tumors. The agents are especially useful in the treatment of animal and human cancers. Two preferred agents in this class, especially for use in the treatment of tumors are 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)-2-(2-chloroethyl)aminocarbonylhydrazine and 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)-2-methylaminocarbonylhydrazine. These agents are characterized by the following: they are incapable of undergoing inactivation by the denitrosation mechanism proposed for the inactivation of the CNUs; they are incapable of generating a hydroxyethylating species by the mechanism proposed for the CNUs; and they are capable of chloroethylation or methylation and carbamoylation. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
This is a divisional of U.S. patent application Ser. No. 09/208,313, filed Dec. 9, 1998, now abandoned. Reference is made to commonly-assigned U.S. patent application Ser. No. 09/207,703 filed Dec. 9, 1998, now U.S. Pat. No. 6,361,886, entitled “Electroluminescent Device Improved Hole Transport Layer” by Shi et al; U.S. patent application Ser. No. 09/208,172 filed Dec. 9, 1998, now U.S. Pat. No. 6,465,115, entitled “Electroluminescent Device with Anthracene Derivatives Hole Transport Layer” by Shi et al; U.S. patent application Ser. No. 09/208,071 filed Dec. 9, 1998, now abandoned, entitled “Electroluminescent Device with Arylethylene Derivatives in Hole Transport Layer” by Shi et al; and U.S. patent application Ser. No. 09/191,705 filed Nov. 13, 1998, now abandoned, entitled “A Multistructured Electrode For Use With Electroluminescent Devices” by Hung et al, the disclosures of which are incorporated herein.
FIELD OF THE INVENTION
The present invention relates to organic electroluminescent devices.
BACKGROUND OF THE INVENTION
Organic electroluminescent devices are a class of opto-electronic devices where light emission is produced in response to an electrical current through the device. (For brevity, EL, the common acronym for electroluminescent, is sometimes substituted.) The term organic light emitting diode or OLED is also commonly used to describe an organic EL device where the current-voltage behavior is non-linear, meaning that the current through the EL device is dependent on the polarity of the voltage applied to the EL device. In this embodiment, the term EL and EL devices will include devices described as OLED.
Organic EL devices generally have a layered structure with an organic luminescent medium sandwiched between an anode and a cathode. The organic luminescent medium usually refers to an organic light emitting material or a mixture thereof in the form of a thin amorphous or crystalline film. Representatives of earlier organic EL devices are Gurnee et al U.S. Pat. No. 3,172,862, issued Mar. 9, 1965; Gurnee U.S. Pat. No. 3,173,050, issued Mar. 9, 1965; Dresner, “Double Injection Electroluminescence in Anthracene”, RCA Review, Vol. 30, pp. 322-334, 1969; and Dresner U.S. Pat. No. 3,710,167, issued Jan. 9, 1973. In these prior arts, the organic luminescent medium was formed of a conjugated organic host material and a conjugated organic activating agent having condensed benzene rings. Naphthalene, anthracene, phenanthrene, pyrene, benzopyrene, chrysene, picene, carbazole, fluorene, biphenyl, terpheyls, quarterphenyls, triphenylene oxide, dihalobiphenyl, trans-stilbene, and 1,4-diphenylbutadiene were offered as examples of organic host materials. Anthracene, tetracene, and pentacene were named as examples of activating agents. The organic luminescent medium was present as a single layer having a thickness much above 1 micrometer. The voltage required to drive the EL devices was as much as a few hundreds volts, thus the luminous efficiency of these EL devices was rather low.
In commonly-assigned U.S. Pat. No. 4,356,429, Tang further advanced the art of organic EL device by disclosing a bi-layer EL device configuration. The organic luminescent medium in this bi-layer configuration comprises of two extremely thin layers of organic film (<1.0 micrometer in combined thickness) sandwiched between the anode and cathode. The layer adjacent to the anode, termed the hole-transport layer, is specifically chosen to transport predominantly holes only in the EL device. Likewise, the layer adjacent to the cathode is specifically chosen to transport predominantly electrons only in the EL device. The interface or junction between the hole-transport layer and the electron-transport layer is referred to as the electron-hole recombination zone where the electron and hole recombine to produce electroluminescence with least interference from the electrodes. This recombination zone can be extended beyond the interface region to include portions of the hole-transport layer or the electron-transport layer or both. The extremely thin organic luminescent medium offers reduced electrical resistance, permitting higher current densities for a given voltage applied on the EL device. Since the EL intensity is directly proportional to the current density through the EL device, this thin bi-layer construction of the organic luminescent medium allows the EL device to be operated with a voltage as low as a few volts, in contrast to the earlier EL devices. Thus, the bi-layer organic EL device has achieved a high luminous efficiency in terms of EL output per electrical power input and is therefore useful for applications such as flat-panel displays and lighting.
Commonly-assigned Tang U.S. Pat. No. 4,356,429 disclosed an EL device formed of an organic luminescent medium includes a hole transport layer containing a 1000 Angstrom of a porphyrinic compound such as copper phthalocyanine, and an electron transport layer of 1000 Angstrom tetraphenylbutadiene in poly(styrene). The anode was formed of a conductive indium-tin-oxide (ITO) glass and the cathode was a layer of silver. The EL device emitted blue light when biased at 20 volts at an average current density in the 30 to 40 mA/cm 2 range. The brightness of the device was 5 cd/m 2 .
Further improvements in the bi-layer organic EL devices were taught by commonly-assigned Van Slyke et al U.S. Pat. No. 4,539,507. Van Slyke et al realized dramatic improvements in EL luminous efficiency by substituting the porphyrinic compounds of Tang in the hole-transport layer with an amine compound. With an aromatic tertiary amine such as 1,1-bis(4-di p-tolylaminophenyl)cyclohexane as the hole-transport layer and an electron transport layer of 4,4′-bis(5,7-di-t-pentyl-2-benzoxazolyl)-stilbene, the EL device was capable of emitting blue-green light with a quantum efficiency of about 1.2% photon per injected charge when biased at about 20 volts.
The use of aromatic amines as the material for the hole-transport layer in organic EL devices has since been generally recognized as numerous prior arts have disclosed the utility of various classes of amines in enhancing the EL device performance. Improvements in the hole-transport material parameters include higher hole transport mobility, more amorphous structures, higher glass transition temperature, and better electrochemical stability. Improvements in the organic EL devices with these improved amines include higher luminous efficiency, longer operational and storage life, and a greater thermal tolerance. For example, the improved arylamine hole transport materials have been disclosed in commonly-assigned U.S. Pat. No. 5,061,569 by VanSlyke et al. A series of aromatic amines with glass transition temperature as high as 165° C. designed for high temperature EL devices has been disclosed in commonly-assigned U.S. Pat. No. 5,554,450 by Shi et al. A novel π-conjugated starburst molecule 4,4′,4″-tris(3-methylphenylamino)triphenylamine (m-MTDATA), which forms a stable amorphous glass and functions as an excellent hole transport material, was disclosed in U.S. Pat. No. 5,374,489 by Shirota et al.
The use of organic compounds outside the aromatic amines class for the hole-transport layer in organic EL devices is not common, given the well-known hole-transport properties of the aromatic amines. However, there is a significant disadvantage of using aromatic amines as the hole-transport layer in the bi-layer EL device. Because amines are generally strong electron donors, they can interact with the emissive materials used in the electron-transport layer, resulting in the formation of fluorescence quenching centers and a reduction in the EL luminous efficiency.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide organic compounds outside the class of aromatic amines as the hole transport layer in organic EL devices, which result in enhanced EL performance.
This object is achieved in an organic multilayer electroluminescent device including an anode and cathode, and comprising therebetween:
a hole transport layer; and
an electron transport layer disposed in operative relationship with the hole transport layer;
wherein:
the hole transport layer includes an organic compound having the formula:
wherein:
Ar is an aryl moiety;
n is an integer of from 1 to 6, and
substituents R 1 and R 2 are each individually hydrogen, or alkyl of from 1 to 24 carbon atoms; aryl or substituted aryl of from 5 to 28 carbon atoms; or heteroaryl or substituted heteroaryl of from 5 to 28 carbon atoms; or fluorine, chlorine, bromine; or cyano group.
Polyphenyl hydrocarbon that are used in the hole transporting layer have the feature that do not need to include alkylamino- or arylamino-moieties;
The polyphenyl hydrocarbon or fused polyphenyl hydrocarbon in accordance with the present invention have an ionization potential larger than 5.0 eV.
The hole transport layer in accordance with the present invention effectively works with the electron transport layer or an emissive layer or an electron transport layer which also functions as an emissive layer to provide a highly efficient electroluminescent device.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates the cross-section of a bi-layer organic EL device;
FIG. 2 illustrates the cross-section of an EL device with a modified bi-layer structure; and
FIG. 3 illustrates the energy level diagram of an organic EL device with a bi-layer structure as described in FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates the basic structure used in the construction of organic EL device of this invention. It is a bi-layer structure comprising an organic hole transport layer 30 and an organic electron transport layer 40 . The electron transport layer is also the emissive layer from which electroluminescence originates. Together, they form the organic EL medium 50 . The anode 20 is adjacent to the hole transport layer and the cathode 60 is adjacent to the electrode transport layer. The substrate is layer 10 . This figure is for illustration only and the individual layer thickness is not scaled according to the actual thickness.
FIG. 2 illustrates an alternative construction of the organic EL device of this invention. It is a modified bi-layer structure. The EL medium contains an emissive layer between the hole transport layer and the electron transport layer. This emissive layer is the layer from which electroluminescence originates. Thus, layer 300 is the hole transport layer, layer 400 is the emissive layer, layer 500 is the electron transport layer, and together they form the electroluminescent medium 600 . Layer 200 is the anode and layer 700 is the cathode. The substrate is layer 100 . This figure is for illustration only and the individual layer thickness is not scaled according to the actual thickness.
FIG. 3 illustrates the energy level diagram of an organic EL device with a bi-layer structure as described in FIG. 1 . The organic EL medium is represented by a hole-transport layer with a characteristic low ionization potential energy, and an electron transport layer with a relatively higher ionization potential energy. The ionization potential energy or ionization potential (IP) for a molecular solid is defined as the energy difference between the vacuum level and the highest occupied molecular orbital (HOMO) level of the solid. The vacuum level is usually referred to as the reference level from which the energy levels of the molecular solid are measured. The HOMO is the highest energy level filled with electron and in which the hole is free to move. Similarly, the lowest unoccupied molecular orbital (LUMO) is the lowest energy level devoid of electron and in which free electron is free to move. The energy difference between HOMO and LUMO is the bandgap within which there are no available molecular orbital states. The IP value is a measure of the minimum energy required to remove an electron from the molecular solid and can be easily obtained experimentally by photoemission techniques which have been well described in the literature.
The bi-layer structure as illustrated in FIG. 1 is designed to confine the electron hole recombination at the interface between the hole transport layer and the electron transport layer. This confinement is accomplished by establishing either an electron injection barrier or a hole injection barrier or both at the interface. Referring to the hole injection barrier, it is the difference between the HOMO levels of the hole transport and electron transport layers, as indicated by the symbol, φ, in FIG. 3 . For large φ values, >0.5 eV, the hole migrating through the hole transport layer towards the interface will be unable to overcome the potential energy barrier and will thus be trapped at the hole transport layer side of the interface. Likewise, the electron injection barrier is the difference between the LUMO levels and a large electron injection barrier for electron injection will localize the electron at the electron transport layer side of the interface. As a result of these charge localizations created by a proper choice of the hole transport and electron transport materials, the electron hole pair will tend to recombine at the interface producing electroluminescence which is characteristics of the interface.
Conventional hole transport materials used in EL devices are mostly arylamines because their hole mobility is among the highest found in common organic materials. Materials with a high mobility are desirable for current-driven devices such as organic EL as the voltage require to operate the device will be low. The arylamines are also known to have the lowest ionization potentials among organic materials. Thus, for creating a hole injection barrier between the hole transport layer and the electron transport layer in a bi-layer EL device, arylamines are appropriate. Highly efficient EL devices have been produced using a variety of arylamines as the hole transport layer.
A class of arylamines found particularly useful in organic EL devices is represented by formula II:
wherein
Ar is an arylene group, and arylene moieties are phenyl or phenylene moieties.
n is an integer of from 1 to 4, and
R 1 , R 2 , R 3 and R 4 are independently selected aryl groups.
These arylamines are particularly useful as the hole transport material in EL devices.
Although arylamines are useful as hole transport materials in EL devices, they do have a number of deficiencies. First, as a class of organic materials, they are relatively strong electron donors, meaning that they can be easily oxidized and therefore are unstable in amibient environments. Second, when used as a hole transport layer adjacent to an electron transport layer in an EL device, the arylamines may interact with the electron transport layer to produce non-emissive centers which will result in a loss of electroluminescence. Third, because of the low ionization potential of the arylamines, the hole injection barrier formed between the arylamine hole transport layer and the electron transport layer will cause the holes to localize in the arylamines which will also result in a loss of electroluminescence. For these reasons, new hole transport materials are useful to further improve the EL device performance.
The new hole transport materials in this invention include polyphenyl hydrocarbons with a molecular structure containing at least 20 carbon atoms;
A representative class of the hole transport materials includes:
a) benzene linked polyphenyl hydrocarbons of formula III:
wherein:
n is integer from 1 to 6; and
Ar is a phenyl or substituted phenyl moiety; the substituents on the phenyl moiety are individually hydrogen, or alkyl of from 1 to 24 carbon atoms; aryl or substituted aryl of from 5 to 28 carbon atoms; heteroaryl or substituted heteroaryl of from 5 to 28 carbon atoms; fluorine, chlorine or bromine atoms; or a cyano group.
The following molecular structures constitute specific examples of benzene linked polyphenyl hydrocarbons represented by the general formula III. These compounds are particularly useful as the hole transport material in EL devices.
b) naphthalene linked polyphenyl hydrocarbons of formula IV:
wherein:
n is integer from 1 to 4;
Ar is a phenyl or substituted phenyl moiety; the substituents on the phenyl moiety are individually hydrogen, or alkyl of from 1 to 24 carbon atoms; aryl or substituted aryl of from 5 to 28 carbon atoms; heteroaryl or substituted heteroaryl of from 5 to 28 carbon atoms; fluorine, chlorine or bromine atoms; or a cyano group.
The following molecular structures constitute specific examples of naphthalene linked polyphenyl hydrocarbons represented by the general formula IV. These compounds are particularly useful as the hole transport material in EL devices.
c) phenanthrene linked polyphenyl hydrocarbons of formula V:
wherein:
Ar is a phenyl or substituted phenyl moiety; the substituents on the phenyl moiety are individually hydrogen, or alkyl of from 1 to 24 carbon atoms; aryl or substituted aryl of from 5 to 28 carbon atoms; heteroaryl or substituted heteroaryl of from 5 to 28 carbon atoms; fluorine, chlorine or bromine atoms; or a cyano group.
The following molecular structures constitute specific examples of phenanthrene linked polyphenyl hydrocarbons represented by the general formula V. These compounds are particularly useful as the hole transport material in EL devices.
c) fluorene linked polyphenyl hydrocarbons of formula VI:
wherein:
R is an alkyl group of from 1 to 12 carbon atoms; and
Ar is a phenyl or substituted phenyl moiety; the substituents on the phenyl moiety are individually hydrogen, or alkyl of from 1 to 24 carbon atoms; aryl or substituted aryl of from 5 to 28 carbon atoms; heteroaryl or substituted heteroaryl of from 5 to 28 carbon atoms; fluorine, chlorine or bromine atoms; or a cyano group.
The following molecular structures constitute specific examples of fluorene linked polyphenyl hydrocarbons represented by the general formula VI. These compounds are particularly useful as the hole transport material in EL devices.
e) spirophenyl linked polyphenyl hydrocarbons of formula VII, and VIII:
wherein:
Ar is a phenyl or substituted phenyl moiety; the substituents on the phenyl moiety are individually hydrogen, or alkyl of from 1 to 24 carbon atoms; aryl or substituted aryl of from 5 to 28 carbon atoms; heteroaryl or substituted heteroaryl of from 5 to 28 carbon atoms; fluorine, chlorine or bromine atoms; or a cyano group.
The following molecular structures constitute specific examples of spirophenyl linked polyphenyl hydrocarbons represented by the general formula VII, and VIII. These compounds are particularly useful as the hole transport material in EL devices.
In forming the hole transport layer of the organic EL device, the hole transport materials of this invention can be deposited by a number of methods. The preferred method is by vacuum vapor deposition as these aromatic hydrocarbons have good thermal stability and can be sublimed into thin film. Alternately, they can be dissolved in appropriate solvents and be cast into thin film. Other deposition methods such as printing by the inkjet method, thermal transfer, laser abrasion and sputtering are useful.
The bi-layer EL device is the basic structure providing high luminous efficiencies and low-voltage operation. Alternative EL device structures have been demonstrated providing improved device performance. These alternative device structures include features in addition to the basic bi-layer structure such as the following structure (a) hole injection layer as disclosed in U.S. Pat. No. 4,356,429; (b) cathode modification with alkaline or alkaline halides as disclosed in U.S. Pat. No. 5,776,622; (c) anode modification with plasma-deposited flurocarbons as disclosed in the above cited commonly assigned U.S. patent application Ser. No. 09/191,705 to Hung et al, now abandoned and (d) doped emitter layer inserted between the hole transport and electron transport layer as disclosed in U.S. Pat. No. 4,769,292. These EL device structures retain the hole transport layer as one component of the electroluminescent medium. Therefore, the aromatic hydrocarbon or fused hydrocarbon hole transport materials disclosed in this invention are applicable to these EL device structures as well.
A preferred EL device structure comprises an anode, a hole transport layer, an emissive layer, and an electron transport layer. In this preferred EL structure, the emissive layer is capable of transporting electrons as well, thus it can be considered as an electron transport layer with the added function of being highly luminescent. The principle function is to provide efficient emissive centers for electroluminescence. This emissive layer comprises a host material doped with one or more fluorescent dyes (FD). The fluorescent dye is usually present in an amount on the order of a few molar percent or less of the host material and it is sufficient to cause the EL emission to be predominantly that of the fluorescent dye. Using this method, highly efficient EL devices can be constructed. Simultaneously, the color of the EL devices can be tuned by using fluorescent dyes of different emission wavelengths. By using a mixture of fluorescent dyes, EL color characteristics of the combined spectra of the individual fluorescent dyes are produced. This dopant scheme has been described in considerable details for EL devices by Tang in commonly-assigned U.S. Pat. No. 4,769,292.
An important relationship for choosing a fluorescent dye as a dopant capable of modifying the hue of light emission when present in a host material is a comparison of their bandgap potential which is defined as the energy difference between the highest occupied molecular orbital and the lowest unoccupied molecular orbital of the molecule.
Preferred host materials for the emissive layer of the organic EL device disclosed in this invention are metal chelated oxinoid compounds, including chelates of oxine itself (also commonly referred to as 8-quinolinol or 8-hydroxyquinoline or Alq). Another class of preferred host materials is a mix ligand 8-quinolinolato aluminum chelates which have been disclosed in U.S. Pat. No. 5,141,671. Another class of preferred host materials is di-strylstibene derivatives as disclosed in U.S. Pat. No. 5,366,811.
For efficient energy transfer from the host to the dopant molecule, a necessary condition is that the band gap of the dopant is smaller than that of the host material. Preferred fluorescent dyes used as the dopant in the emissive layer include coumarins, stilbenes, distrylstilbenes, derivatives of anthracene, tetracene, perylenes, rhodamines, and arylamines.
The molecular structures of the preferred fluorescent dyes for the emissive layer in the EL device are listed as follows:
Preferred materials for use in forming the electron transporting layer of the organic EL device are metal chelated oxinoid compounds, including chelates of oxine itself (also commonly referred to as 8-quinolinol or 8-hydroxyquinoline). Representative compounds are 8-hydroquinoline of the group III metals such as Al, In, Mg; and of the group II metals such as Mg, Zn; and of the group I metal such as Li.
Preferred materials for use in forming the an anode modified with fluorocarbons as disclosed in the above disclosed commonly assigned U.S. patent application Ser. No. 09/191,705 by Hung et al., now abandoned.
Preferred materials for use in forming the cathode of the EL devices of this invention are Mg, Li, or alloys of these materials as disclosed in U.S. Pat. No. 5,429,884; and commonly-assigned U.S. Pat. No. 5,776,622 by Tang, Hung and others.
EXAMPLES
The invention and its advantages are further illustrated by the specific examples as follows:
Example 1
Synthesis of 2-naphthylene boronic acid
A solution of n-BuLi (1.6 M in hexane, 100 mL, 0.16 mol) was added via an addition funnel to 2-bromonaphthalene (30.0 g, 0.14 mol) in 200 mL of dry THF at −78° C. The yellow suspension was stirred at this temperature for a half hour, a solution of B(OMe) 3 (26.6 mL, 29.1 g, 0.28 mol) in 150 mL of dry THF was added dropwise, with the temperature kept below −60° C. The resulting colorless solution was allowed to warm to room temperature overnight, then 300 mL of 10 M HCl was added and the mixture stirred for a further one hour under nitrogen. Water and ether were added, and the aqueous layer was extracted several times with ether. The combined organic extracts were dried over MgSO4 and evaporated under reduced pressure to yield a white solid (21.0 g, 95%), which was used in the coupling reaction without further purification.
Example 2
Synthesis of 3,5-di-(m-tolyl)bromobenzene
To a solution of 1,3,5-tribromobenzene(47.3 g, 0.15 mol) in 150 mL of dry tetrahydrofuran (THF) was added 0.5 g of bis-(triphenylphosphine)-palladium(II) chloride under nitrogen. After the solution was degassed with dry nitrogen for 5 minutes, 155 mL of m-tolyl magnesium bromide (0.2 M in THF) was added through an addition funnel at 70° C. under nitrogen. The reaction mixture was stirred under reflux for another two hours after addition. After cooling the reaction mixture was quenched by slowly adding 50 mL of 0.5 N HCl with stirring. Then the solvents were removed via a rotary evaporator. The residue was dissolved in hexane and washed with 0.1 M HCl followed by water. After removing the solvent, the crude residue was purified by chromatography on silica gel using hexane as the eluent. After drying, 28.0 g of, 3,5-di-m-tolyl bromobenzene was collected. Yield 55.3%.
Example 3
Synthesis of 3,5-(1-naphthyl)bromobenzene
To a solution of 1,3,5-tribromobenzene (105.0 g, 0.22 mol) in 500 mL of dry tetrahydrofuran (THF) was added 1.0 g of bis-(triphenylphosphine)-palladium(II) chloride under nitrogen. After the solution was bubbled with dry nitrogen for 5 minutes, 1-naphthylmagnesium bromide, which was prepared from 150.0 g (0.48 mol) of 1-bromonaphthalene in 100.0 mL of dry THF and clean, dry 18.0 g of magnesium in 250 mL of dry THF with 1,2-dibromoethane as an initiator, was added through an addition funnel at 70° C. under nitrogen. The reaction mixture was stirred under reflux for another two hours. After the reaction mixture was cooled, it was quenched by slowly adding 25.0 mL of 5% HCl with stirring. Then the solvents were removed via a rotary evaporator. The residue was dissolved in dichloromethane and washed with 0.1 M HCl followed by water. After removal of solvents, the crude residue was purified by crystallizing from heptane. A 57.0 g of pure 3,5-di(1-naphthyl)bromobenzene was collected. Yield 63.5%.
Example 4
Synthesis of 1,2,4,5-tetra-p-biphenylylbenzene (Compound 10)
Dry Mg turnings (3.9 g, 0.16 mol) and 30 mL of anhydrous THF were added to a 1 L 3-necked round-bottomed flask equipped with a condenser, a nitrogen inlet, an additional funnel and a magnetic stirring bar. 4-Bromobiphenyl (37.2 g, 0.16 mol) was dissolved in 150 mL of THF and placed in an additional funnel. The reaction flask was placed in a 50° C. oil bath and one crystal of iodine was added. Once the reaction started 4-bromobiphenyl was added dropwise to the reaction. After addition, the brownish reaction was heated at reflux for another hour and then cooled to room temperature. A suspension of hexabromobenzene (11.0 g, 0.02 mol) in 150 mL of THF was added dropwise from an additional funnel to the reaction and the mixture was stirred at room temperature overnight. The reaction was quenched with ice and 8% hydrochloric acid and extracted with 400 mL of methylene chloride. The organic layer was washed with saturated sodium chloride solution and dried over magnesium sulfate. Solvent was evaporated and the crude product was washed with hexane and filtered to give pure product.
Example 5
Synthesis of 1,2,4,5-tetra-β′-naphthylbenzene (Compound 9)
The procedure used to synthesize compound 10 was followed.
Example 6
Synthesis of 1,2,4,5-tetra-6′-methoxy-β′-naphthylbenzene (Compound 11)
The procedure used to synthesize compound 10 was followed.
Example 7
Synthesis of 3,3′″,5,5′″-tetra-α-naphthyl-p-terphenyl (Compound 28)
A solution of 3,5-di-α-naphthyl bromobenzene (10 g, 0.0244 mol) in anhydrous THF (70 mL) was added dropwise to magnesium turnings (0.59 g, 0.0244 mol) in 10 mL THF. The solution was heated at 60° C. during the addition and the reaction was initiated using 1,2-dibromoethane. After the addition was complete, the brown solution was heated at reflux for 2 hrs. and then cooled to room temperature. In a separate flask, 1,4-diiodobenzene (2.69 g 0.008 mol) and 0.3 g of dichlorobis(triphenyl phosphine)palladium(II) were placed under nitrogen and 30 mL of anhydrous THF was added. The Grignard reagent prepared about THF solution was then added using needle-transfer and an orange solution resulted. Heat was applied and the solution turned to almost black. The mixture was then heated at reflux for 45 min. and cooled to room temperature during which time a solid precipitated out of solution. A 2.0 M solution of HCl was added to the mixture and after stirring for 30 minutes, the aqueous layer was removed. The solid precipitate was collected by filtration and washed with water and diethyl ether to yield a white solid (4.9 g, 82%)
Example 8
Synthesis of 3,3″,5,5″-tetra-naphthyl-p-quaterphenyl (Compound 29)
A solution of 3,5-di-α-naphthyl bromobenzene (10.0 g, 0.0244 mol) in anhydrous THF (70 mL) was added dropwise to magnesium turnings (0.59 g, 0.0244 mol) in 10 mL THF. The solution was heated at 60° C. during the addition and the reaction was initiated using 1,2-dibromoethane. After the addition was complete, the brown solution was heated at reflux for 2 hrs. and then cooled to room temperature. In a separate flask, 4,4′-diiodobiphenyl (3.3 g 0.008 mol) and 0.3 g of dichlorobis(triphenyl phosphine)palladium(II) were placed under nitrogen and 30 mL of anhydrous THF was added. The Grignard reagent prepared about THF solution was then added using needle-transfer and an orange solution resulted. Heat was applied and the solution turned to almost black. The mixture was then heated at reflux for 45 min. and cooled to room temperature during which time a solid precipitated out of solution. A 2.0 M solution of HCl was added to the mixture and after stirring for 30 minutes, the water layer was removed. The solid precipitate was collected by filtration and washed with water and diethyl ether to yield a white solid (5.3 g, 81%)
Example 9
Synthesis of 2,7-biphenyl-9,9-bis(4-methoxyphenyl)-fluorene (Compound 53)
A solution of 4-brombiphenyl (10.43 g, 0.0448 mol) in anhydrous THF (90 mL) was added dropwise to magnesium turnings (1.09 g, 0.0448 mol) in 10 mL THF. The solution was heated at 60° C. during the addition and the reaction was initiated using 1,2-dibromoethane. After the addition was complete, the red solution was heated at reflux for 2 hrs. and then cooled to room temperature. In a separate flask, 2,7-dibromo-9,9-bis(4-methoxyphenyl)-fluorene (10 g, 0.0187 mol) and 0.65 g of dichlorobis(triphenyl phosphine)palladium(II) were placed under nitrogen and 100 mL of anhydrous THF was added. The Grignard reagent prepared about THF solution was then added using double-needle transfer and an orange solution resulted. Heat was applied and the solution turned a darker orange. The mixture was then heated at reflux for 2 hours during which time a yellow solid precipitated out of solution. A 2.0 M solution of HCl was added to the mixture and after stirring for 30 minutes, the aqueous layer was removed. The solid precipitate was collected by filtration and washed with water and diethyl ether to yield a yellow solid (10.5 g, 83%).
Example 10
Synthesis of 2,7-β-dinaphthyl-9,9-bis(4-methoxyphenyl)-fluorene (Compound 54)
2,7-Dibromo-9,9-bis(4-methoxyphenyl)-fluorene (10.0 g, 0.0187 mol), 2-naphthylboronic acid (7.7 g, 0.0448 mol), Tetrakis(triphenylphosphine)palladium(0) (1.0 g), 75 mL of Toluene and 30 mL of 2N K 2 CO 3 were all placed into a round-bottom flask equipped with a stirring bar and a condenser. The mixture was stirred vigorously and heated at reflux overnight. After cooling to room temperature, the aqueous layer was removed and the solid precipitate was collected by filtration. The resulting solid was heated gently in a 2M HCl solution for 30 minutes and then collected once again by filtration and washed with water and diethyl ether. After drying, 9.17 g of 2,7-β-dinaphthyl-9,9-bis(4-methoxyphenyl)-fluorene was collected. Yield 78%.
The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.
PARTS LIST
10
substrate
20
anode
30
hole transport layer
40
electron transport layer
50
organic EL medium
60
cathode
100
substrate
200
anode
300
hole transport layer
400
emissive layer
500
electron transport layer
600
EL medium
700
cathode | An organic multilayer electroluminescent device including an anode and cathode, and comprising therebetween:
a hole transport layer; and
an electron transport layer disposed in operative relationship with the hole transport layer;
wherein:
the hole transport layer includes an organic compound having the formula:
wherein:
Ar is an aryl moiety;
n is an integer of from 1 to 6; and
substituents R 1 and R 2 are each individually hydrogen, or alkyl of from 1 to 24 carbon atoms; aryl or substituted aryl of from 5 to 28 carbon atoms; or heteroaryl or substituted heteroaryl of from 5 to 28 carbon atoms; or fluorine, chlorine, bromine; or cyano group. | 8 |
FIELD OF THE INVENTION
[0001] This invention is related generally to flow meter technology. More particularly, the invention relates to the field of digital flow meters and systems for use in environments in which it is desired to measure flow rates and temperatures over a wide range without invading or affecting the flow of the fluid which is to be measured.
BACKGROUND OF THE INVENTION
[0002] Flow meters which operate according to a calorimetric principle are used in industrial applications. The calorimetric principle involves heating a heat sensitive element, such as a thermistor or resistance temperature device or detector, which is a temperature dependent element or resistor during exposure to the flow of the fluid to be monitored. The flow cools the heat sensitive element resulting in a resistance change as a function of the velocity of the flow. This resistance change can be evaluated to determine the flow rate. Since the temperature change of the heat sensitive element may be the result of changes in the temperature of the medium as well as the flow, special measures must be taken to compensate for or eliminate the influence of changes in the temperature of the medium. The present invention relates to an improved method and apparatus for measuring flow using calorimetric principles and providing improved turndown ratios and high turndown values by varying the inner diameter of the assembly in which fluid flow is measure.
[0003] One of the primary disadvantages with calorimetric flow meters presently available is the low turndown ratio achieved and low turndown values provided, by such meters. The digital flow meter of the present invention overcomes this disadvantage by providing a meter having turndown ratios is excess of 100 to 1, and preferably in excess of 1000 to 1, and more preferably in excess of 2400 to 1, increasing the ability and accuracy of fluid measurement in low flow situations.
[0004] In addition, existing meters are limited to use with, and calibration in conjunction with, a known fluid. Field conditions often involve mixtures with gases being dissolved therein at different levels. By monitoring the amount of time it takes the fluid to increase in temperature when flow stops and communicating such information digitally to a controller, the data from the meter can be field calibrated for fluids that change due to external dynamics. (As an example only, Thiol mixtures used for odorizing natural gas being used as a driver). As used herein, fluid means a substance that continually deforms or flows under an applied shear stress. Fluids may include liquids, gases, plasmas, slurries, admixtures, liquid carriers and the like, or any combination thereof
OBJECTS OF THE INVENTION
[0005] It is an object of the present invention to provide a digital flow meter capable of achieving turndown ratios is excess of 100 to 1 and in excess of 1000 to 1 and as high as in excess of 2400 to 1 to provide accurate flow rate detection in extremely low fluid flow environments.
[0006] Another object of the present invention is to provide a digital flow meter with is capable of calibration in field environments with unknown fluids to achieve accurate flow measurements.
[0007] Yet another object of the present invention is to provide a digital flow meter which monitors the time it takes the fluid to increase in temperature when flow stops and communicating such information digitally to a controller. A further object of the present invention is to provide a digital flow meter which can provide data which allows the meter to be field calibrated for fluids that change due to external dynamics. Yet a further object of the present invention is to provide a digital flow meter with a measuring tube providing multiple temperature measurements for increasing the accuracy of measuring the fluid flow rate through a wide range of fluid rates.
[0008] Another object of the present invention is to provide a digital flow meter with a measuring sections or machined assemblies having varying inner diameters (ID) over a length to increase the accuracy and sensitivity of the measurement of the fluid flow.
[0009] These and other objects of the invention will be apparent from the following descriptions and from the drawings.
SUMMARY OF THE INVENTION
[0010] Accordingly, the present invention provides a digital flow meter for measuring the flow of a medium including but not limited to a slurry, liquid, plasma, admixture, gas or other fluid using a flow sensor comprising a first resistance temperature device or “RTD” as a temperature sensor arranged along a sampling length through which the fluid flows. The flow sensor also includes a heating device or circuit for periodically heating a second RID to a first temperature. Once heated through controlled pulsing of a power source, the second RTD is then allowed to cool and its resistance changes as a function of the flowing fluid. The changing resistance is reflected in an output signal from the second RTD. A bridge circuit is connected with the second RTD to maintain a constant voltage as the temperature of the fluid changes, thereby to compensate for fluctuations in the temperature of the fluid, whereby the output signal is solely a function of the flow of the fluid. The bridge circuit may include a micro-controller, microprocessor, or a similar digital circuit which accepts inputs, including pulses and temperatures, which can be linearized by the circuit to determine or otherwise obtain the flow rate of the fluid.
[0011] According to a further object of the invention, the heating device preferably comprises a resistance element arranged in spaced relation from the second RTD and a pulse generator connected with the resistance element for periodically energizing the resistance element to heat the second RTD to the first temperature.
[0012] The control device may comprise a transistor, a current or voltage source, an operational amplifier, a micro-controller, a microprocessor or similar integrated or digital circuit. The term “temperature sensitive element” as used herein may include resistance temperature devices, resistance temperature detectors, thermistors, thermocouples temperature sensitive diodes, heatable temperature detectors, other transistors or solid state devices and the like.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] In order that the advantages of the invention will be readily understood, a more detailed description of the invention briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which:
[0014] FIG. 1 is a perspective view of an embodiment of the inventive digital flow meter with enhanced turndown ratio;
[0015] FIG. 1A is a top view of the embodiment of FIG. 1 ;
[0016] FIG. 2 is a perspective view of the flow tube used for fluid flow measurement in the digital fluid flow meter of the present invention;
[0017] FIG. 3 is a top view of the flow tube of FIG. 2 ;
[0018] FIG. 4 is a side view of the flow tube of FIG. 2 ;
[0019] FIG. 5 is a cross-section view of the flow tube of FIG. 2 taken along lines 5 - 5 of FIG. 4 ;
[0020] FIG. 6 is a cross-section view of the flow tube of FIG. 2 taken along lines 6 - 6 of FIG. 4 ;
[0021] FIG. 7 is a cross-section view of the flow tube of FIG. 2 taken along lines 7 - 7 of FIG. 4 ;
[0022] FIGS. 8A and 8B together are a circuit schematic showing two flow sensors used to measure fluid flow in the digital fluid flow meter of the present invention;
[0023] FIG. 8C is a circuit schematic showing an alternative embodiment of an RTD header;
[0024] FIG. 9 is a circuit schematic of the analog to digital converter which converts the temperature outputs of the flow sensors shown in FIGS. 8A and 8B ;
[0025] FIG. 10 is a circuit schematic showing a circuit for voltage regulation to produce the 3.3V DC from the incoming 24V DC power source
[0026] FIGS. 11A , 11 B and 11 C together are a circuit schematic showing the micro-controller to linearize and provide the output of the measure of fluid flow in the digital fluid flow meter of the present invention;
[0027] FIG. 12 is pulse diagram of a no load wave form applied to the circuit of FIGS. 8-11 ; and
[0028] FIG. 13 is pulse diagram of a load wave form applied to the circuit of FIGS. 8-11 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0029] A preferred embodiment of the digital flow meter of the present invention is shown in FIGS. 1 and 1A . As illustrated, a digital flow meter 10 with enhanced turndown ratio includes housing 12 with top 14 encasing the electronic circuitry. Top 14 is secured to housing 12 through fasteners 16 . Fasteners 16 may include rivets, screws, bolts or the like. Power is provided to the digital flow meter through input cord 18 . A preferred embodiment of flow meter 10 includes measuring tube 20 having an input end 22 and an output end 24 . The measurement described below is taken between ends 22 , 24 in measurement section 26 of measuring tube 20 . Fluid flows in the direction from the input end 22 to the output end 24 as shown by the arrows in FIGS. 1 and 1A . It may be appreciated by those skilled in the art that measuring tube 20 may include one or more machined assemblies. Such assemblies may include solid bar stock which is machined with varying inner diameters, varying diameters of bar stock machined with varying inner diameters connected as required, multiple tubes welded together, a manufactured manifold with multiple tubes and the like.
[0030] Flow meter 10 includes one or more flow sensors. Each flow sensor includes one reference resistance temperature device or detector (RTD) and one resistance temperature device or detector (RTD) dissipating heat into the fluid being measured. The flow sensors (not shown) are positioned on measuring tube 20 at various predetermined positions between input end 22 and output end 24 . It will be appreciated by those skilled in the art that placement of the various RTD members is important to obtain the proper and most accurate measurements. Hence it is preferable for the various RTD members forming the flow sensor to be placed the same distance apart with each flow sensor. In addition, it is preferable to keep the RID members as close to parallel as possible with respect to each flow sensor. It is also preferable to keep the RTD members as close to parallel as possible from one flow sensor to the next.
[0031] Referring to FIGS. 2-7 , measuring tube 20 , having input end 22 , output end 24 and measurement section 26 , is shown in detail. As can be seen, within measurement section 26 , there are formed three reduced thickness areas 28 A, 28 B and 28 C. Each of these reduced thickness areas preferably forms a flat surface on which one of the flow sensors is placed. It is preferred that the RTD members be positioned as close as possible to one another, and preferably no more than 0.05″ apart. This positioning provides the most accurate measurements and prevents temperature variations from affecting the measurements. It is preferred that the reduced thickness areas ( 28 A, 28 B and 28 C) be thermally isolated from each other to further improve the accuracy of the temperature measurements and the accuracy of the measurement of the flow rate of the fluid.
[0032] As can be seen in FIG. 4 , each reduced thickness area is formed such that the distance from the wall of the inner diameter of the tube is constant. Such distance between the top of the reduced thickness area to the inner diameter wall of tube 20 is preferably 0.164″. It may be appreciated that distance from the top of the area of reduced thickness to the inner diameter of tube 20 may vary depending on pressure requirements, operating environments and the like. Accordingly, a preferred range may be from approximately 0.05 to approximately 0.25 for fluid flow rates from about 0.05 ml/min to about 120 ml/min. It is desired that this distance be chosen to reduce the response time of the measuring sensor and to reduce any error which may be introduced by the ambient temperature within the measuring areas. Such positioning of the flat surface is required to provide consistency in measuring depth from the RID to the fluid flow within tube 20 .
[0033] As illustrated in FIGS. 3-7 , to provide the improve the sensitivity of the digital flow meter, a reduction in the diameter of the measuring tube 20 is preferable. Such diameter reduction can be in multiple sections as required by the application. As illustrated in FIGS. 3 and 4 , three sections are shown, specifically 30 A, 30 B and 30 C. Each section may be from approximately 1″ to approximately 3″ in length and preferably from approximately 1″ to approximately 2″ in length. It is preferred that each section have at least 10 inner diameter measurements in length before the flat begins ( 28 A, 28 B and 28 C) and 5 inner diameter measurements in length after the flat ( 28 A, 28 B and 28 C) ends. This assures the most constant possible flow profile and provides the greatest accuracy in the measurements being obtained by the digital flow meter. It will be appreciated by those skilled in the art that the number of flats included on tube 20 may be at least 2, more preferably 3, but can be up to N as required by the type of fluid and the type of fluid flow to be measured. Increasing the number of flats or reduced thickness areas increases the sensitivity of the fluid low meter. Such increase may also increase the turndown ratio or rangeability of the fluid flow meter.
[0034] The machining assemblies, of which measuring tube 20 is one preferred variation, may be constructed of any type of compatible material as necessary for the particular application. Preferably, the machining assemblies form at least two (2) inner diameters that are progressively smaller as required by the particular application. Such may be formed by drilling, various machining operations, construction using various preformed materials and similar methods of construction, machining, forming or the like. Multiple inner diameters are formed, and may be preferably offset drilled, so that they become smaller in the direction of fluid flow and may be from 2, 3, 4 N in number where ID 1 >ID 2 >ID 3 >ID N . Providing multiple inner diameters that are reduced, multiplies the effective turndown ratio allowing measurement of fluid flow rates as low as approximately 0.1 ml/min to approximately 0.05 ml/min.
[0035] The turndown ratio of a meter may be defined as a flow measurement term that indicates the range a specific flow meter, or meter type, is able to measure with acceptable accuracy. It is also known as rangeability. Rangeability may be considered the ratio of the maximum flow to the minimum flow of a meter. Measurement of different types of fluids may require more sensitive meters to produce accurate flow measurements. The more sensitive the meter needs to be to accurately measure low rate fluid flow, the higher the turndown ratio needs to be. It is important to obtain a high turndown ratio to match the flow meter capabilities in low flow rate applications.
[0036] As an example, reducing the ID of measurement tube 20 by a factor of 10 times from the first section to the second section and by another factor of 10 times from the second section to the third section provides the following turndown ratios:
[0000] Turndown at flat 1=10(10 ml/min-100 ml/min)
Turndown at flat 1=10(1 ml/min-10 ml/min)
Turndown at flat 1=10(0.1 ml/min-1 ml/min)
Total turndown=10×10×10=1000
[0037] Inner diameters of approximately 1/16″ (0.0625″) to approximately ¼″ (0.25″) may be used based on the application required. More preferably, inner diameters of approximately 1/16″ (0.0625″) to approximately ⅛″ (0.125″) may be used.
[0038] The machined assemblies used for measuring herein, which as described above include measuring tube 20 , may be constructed from stainless steel bar stock which is machined, formed constructed or otherwise prepared as required to form the necessary inner diameter for each required application. Such bar stock may be drilled as necessary or otherwise formed with the required inner diameter to provide the measuring locations as necessary. In other applications, copper or iron may be preferred, but any type of compatible material may be used. It may also be contemplated to coat the inner surface of the machined assemblies to achieve performance is specialty applications. Any type of coating necessary to improve measurement characteristics or performance is contemplated herein.
[0039] The digital flow meter of the present invention may be used in a variety of applications in which it is desired to accurately measure the flow rate of a fluid, known or unknown, behind a wall or within a tube. Such applications may include but are not limited to flow of natural gas, steam, water, petroleum any type of liquid, slurry, admixture or the like. Accurate measurements are obtained with fluid flow rates from approximately 0.05 ml/min to approximately 120 ml/min. Such flow rate ranges in conjunction with ID reductions for typical applications may provide turndown ratios in excess of 2400 to 1 or in excess of a total turndown of 2400.
[0040] It will be appreciated that the sensors may be placed directly in the stream of the fluid for taking their measurements. However, it is preferred that the sensors take their measurements in a non-invasive manner such that they are positioned proximate to but not within the flow stream of the fluid. The pulsed signal from the flow sensors are provided to and read by the micro-controller. Linearization and temperature compensation are performed by the micro-controller. The micro-controller includes a modulated bus output (a proprietary bus provided by Sentry Equipment Corporation of Oconomowoc, Wisconsin under the trademark MODBUS®) for sending data to one or more of a plurality of devices including a Distributed Control System (DCS), a Lab station, an analyzer, an analyzing station or the like. It may be appreciated that the digital flow meter of the present invention may have a variety of options, including but not limited to one or more displays, one or more keypads, one or more keyboards, and other input/output devices.
[0041] In operation, fluid passes through the tube and pulse values are read, linearized, temperature compensated and either displayed, located or stored in a register to be read by and through the MODBUS® output. Fluid temperature may also be displayed or read through the MODBUS® output.
[0042] Now turning to the construction and operation of the preferred embodiment of the circuit, reference is made to FIGS. 8-11 . As can be seen in FIGS. 8A , 8 B and 8 C, an ambient sensor controls a “reference” voltage applied to the “−” input of USA. The RTD header is designated as U 15 in FIG. 8B and U 1 in FIG. 8C . FIG. 8B shows one preferred embodiment of the RTD header while a second preferred embodiment is shown in FIG. 8C .
[0043] As shown in FIGS. 8A , 8 B and 9 , the “+” input to U 12 A is “feedback” from the driven sensor. Resistors R 16 , R 17 and R 18 and R 20 are used for a reference voltage at the op-amp U 12 A, U 12 B for detection of ambient temperature. The error between the reference voltage and the feedback voltage is integrated by U 12 A through resistor R 22 . The “gain” of the integrator is proportional to C 41 (the integrating capacitor shown in FIG. 8A ) and inversely proportional to R 22 (shown in FIG. 8A ). In FIG. 8 , resistor R 23 balances the input bias current on the other input. Such circuit configuration prevents the input bias current applied to the op-amp from affecting the circuit performance and ultimate readings provided thereby.
[0044] Resistors R 24 , R 19 (shown in FIG. 8A ) and capacitor C 42 (shown in FIG. 8A ) form an oscillator at U 12 B. The duty cycle of the oscillator will vary as the output of U 12 A varies. Resistors R 27 and R 25 (shown in FIG. 8A ) form a threshold around which the oscillations occur and resistor R 26 provides hysteresis, to make sure the intended oscillation occurs. U 10 (shown in FIG. 8A ) is the power driver for both resistance temperature devices or detectors (RTDs). The output of the driven RTD is pulsed by the drive circuit, so the reference sensor must also be pulsed. This pulsing is necessary so the error signal does not depend on the duty cycle of the drive circuit.
[0045] As also shown in FIGS. 8A and 8B , U 15 is a header that connects to the RTD board. In the embodiment of FIGS. 8A and 8B , the RID header board may include a 1K ohm resistor connected to selected pins of U 15 . As shown in FIGS. 8A and 8B , this RTD is used for the reference voltage applied to U 12 A. As also shown in FIGS. 8A and 8B , a 100 ohm resistor may be connected between selected pins of U 15 . As shown in FIGS. 8A and 8B , this RTD provides the feedback from the 100 ohm RID. A second temperature sensor (U 13 A, U 13 B shown in FIGS. 8A and 8B ) is located on the RID board. U 12 A, U 12 B is for one flow sensor and U 13 A, U 13 B is for a second flow sensor. As shown, this circuit can handle two flow sensors values and two temperature values. Temperatures are read through an analog to digital converter (ADC U 6 in FIG. 9 ), then to the micro-controller (U 2 shown in FIGS. 11A , 11 B and 11 C).
[0046] Each sensor creates a pulse waveform (see FIGS. 12 and 13 ) that is read into the micro-controller. These pulses are denoted as Pulse 1 and Pulse 2 in FIGS. 8A and 8B . The duty cycle of these waveforms correlates to the flow rate of the liquid being measured. As can be seen in FIG. 12 , the duty cycle for such a pulse is approximately 21.9% with a peak to peak voltage of approximately 2.234 volts with a frequency of approximately 113.1 Hz. FIG. 13 illustrates a pulse duty cycle of approximately 77.2% with a peak to peak voltage of approximately 2.266 volts with a frequency of approximately 117.0 Hz. Again referring to FIGS. 8A and 8B , the micro-controller measures the time that the pulse is on vs. the time the pulse is off and calculates the duty cycle of the sensor. Micro-controller (U 2 ) reads the duty cycle and temperature readings, then linearizes these values to obtain an accurate flow rate of the measured liquid.
[0047] Reference throughout this specification to “one embodiment,” “an embodiment,” “a preferred embodiment” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” “in a preferred embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.
[0048] Furthermore, the described features, advantages, and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the invention may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention. While the present invention has been described in connection with certain exemplary or specific embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications, alternatives, modifications and equivalent arrangements as will be apparent to those skilled in the art. Any such changes, modifications, alternatives, modifications, equivalents and the like may be made without departing from the spirit and scope of the invention. | A digital fluid flow meter for measuring fluid flow past a surface on one side of a wall including first and second reduced thickness areas in the wall spaced from one another, a first detector having a first temperature sensitive element thermally coupled to the first reduced thickness area to provide thermal transfer between fluid in contact with the surface and the first detector, a second detector comprising a second temperature sensitive clement thermally coupled to the second reduced thickness area of said wall to provide thermal transfer between fluid in contact with the surface and the second detector. The digital fluid flow meter includes means for sensing the temperature of the first and second temperature sensitive elements, first and second heating elements for heating the respective temperature sensitive elements proximate to the first and second detectors, respectively. The meter includes means for providing input power and control signals to the first and second heating elements and means for transmitting output signals from the temperature sensing means. The wall may be a tube having reduced diameter sections for improving the turndown ratio, total turndown and sensitivity of the digital fluid flow meter. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 11/282,121, filed Nov. 18, 2005, which is a divisional of U.S. patent application Ser. No. 10/124,599, filed Apr. 16, 2002, now U.S. Pat. No. 6,974,447, which claims the benefit of U.S. Provisional Patent Application Ser. No. 60/284,277, filed on Apr. 17, 2001, the entire contents of which are expressly incorporated herein by reference thereto.
TECHNICAL FIELD
The present invention relates to a high gas barrier primary receptacle system, and more particularly to a receptacle system for medical solutions.
BACKGROUND OF THE INVENTION
There is an ever increasing number of therapeutic fluids being developed for delivery by a flexible receptacle. Many of these therapeutic fluids are sensitive as they degrade or react with gases such as oxygen and carbon dioxide. These therapeutic fluids must be protected from contact by such gases to maintain the efficacy of the therapeutic fluid.
For example, hemoglobin solutions are known to lose their ability to function as blood substitutes during storage. A hemoglobin solution loses its ability to function as a blood substitute because of spontaneous transformation of oxyhemoglobin in the solution to methemoglobin, a physiologically inactive form of hemoglobin which does not function as a blood substitute by releasing oxygen into a patient's bloodstream. To improve shelf life, the blood substitutes industry delays loss of function by refrigerating or freezing the solutions, or controlling the oxygenation state of the hemoglobin within the solution.
Therapeutic hemoglobin solutions are typically oxygenated, stored frozen in conventional oxygen-permeable, 200 ml plastic solution bags, and thawed to room temperature hours before use.
WO 99/15289 describes a multiple layer structure for fabricating medical products. The layer structure has a core layer of an ethylene vinyl alcohol copolymer, a solution contact layer of a polyolefin positioned on a first side of the core layer, an outer layer positioned on a second side of the core layer opposite the solution contact layer, the outer layer being selected from the group consisting of polyamides, polyesters and polyolefins, and a tie layer on each side of the core layer. The tie layer is 0.2-1.2 mils in thickness, and is the only layer of the structure which may be composed of ethylene vinyl acetate.
U.S. Pat. No. 6,271,351 describes a method of storing deoxyhemoglobin in a container which is said to exhibit low oxygen permeability. The container is composed of a layered structure including ethylene vinyl alcohol, but does not include ethylene vinyl acetate.
There is a need for containers having minimal oxygen permeability which would enable deoxygenated hemoglobin solutions to be stored for weeks or months at room temperature and then used as a blood substitute.
Receptacles used for the shipping, storing, and delivery of liquids, such as medical or therapeutic fluids, are often fabricated from single-ply or multiple-ply polymeric materials. Two sheets of these materials are placed in overlapping relationship and the overlapping sheets are bonded at their outer peripheries to define a chamber or pouch for containing liquids. It is also possible to extrude these materials as a tube and to seal longitudinally spaced portions of the tube to define chambers between two adjacent seals. Typically, the materials are joined along their inner surfaces using bonding techniques such as heat sealing, radio-frequency sealing, thermal transfer welding, adhesive sealing, solvent bonding, sonic sealing, and laser welding.
It is also common to provide such receptacles with access ports to provide access to the interior of the receptacle. Access ports typically take the form of one or more end ports (transfer tubes) inserted between the sidewalls of the receptacle or panel ports attached to a sidewall of the receptacle. The end ports typically have a fluid passageway with a closure wall positioned inside the passageway to form a fluid tight seal of the receptacle. The closure, typically in the form of a membrane, must be punctured by an access needle or “spike” to allow for delivery of the contents of the receptacle.
Conventional flexible solution receptacles employing end port designs typically use flexible PVC or soft polyolefins such as LDPE to construct the port tubes. Such materials have sufficient elasticity to grip the outside of an access spike to retain the spike during fluid delivery. The inner diameter of the end ports are dimensioned to be smaller than the outer diameter of the access device. Due to the ductility of PVC or LDPE, the port tube can expand about the outside of the access spike to form an interference fit therewith. However, such receptacle and port closure systems are readily permeated by oxygen and other gases such as carbon dioxide. If such receptacles are to be utilized to house a gas sensitive liquid, such packages must utilize a gas barrier overwrap material.
To provide a stand-alone gas barrier primary receptacle, all components of the receptacle system should be fabricated using barrier material. For medical applications where such receptacles are typically disposed of by incineration, it is desirable to construct the receptacle system components from non-halogen containing polymers. Halogen containing compounds have the potential for creating inorganic acids upon incineration. Further, for medical applications, it is also desirable to construct the receptacle system components from polymers having a low quantity of low molecular weight additives, such as plasticizers, as such low molecular weight components can potentially leach out into the fluids contained or transported therein.
It is well known that certain materials provide a high resistance to the ingress of oxygen or other gases. For example, ethylene vinyl alcohol (EVOH) provides a high barrier to the ingress of oxygen. However, EVOH provides a significant design challenge for use in flexible receptacle systems as EVOH is also know to be a very rigid material. A port tube containing a significant quantity of EVOH will have insufficient elasticity to expand around an access device. Thus, such an EVOH containing port tube cannot be dimensioned to be smaller in diameter than an access device.
Due to the variation in the outer diameter dimensions of access devices commercially, it is also difficult to design a single port tube to have an appropriate diameter to form an interference fit with all access devices commercially available. The spike holder or needle holder has sufficient elastomeric properties to form around an access device and form a grasping hold of the access device. The present invention is provided to solve these and other problems.
SUMMARY OF THE INVENTION
The present invention provides a receptacle for a therapeutic fluid susceptible to deterioration on exposure to a gas such as oxygen or carbon dioxide. The receptacle has walls of sheet material each including at least one layer forming a barrier essentially impermeable to said gas, and a seal sealing the walls together in a region thereof. A transfer tube is sealed in the seal having a proximal end in the receptacle, a distal end accessible from outside the receptacle, a flow passage extending between said proximal and distal ends, and a closure blocking flow through said flow passage adapted to be pierced by a tubular needle for transfer of therapeutic through the needle. The transfer tube and closure are essentially impermeable to said gas.
The present invention further provides a transfer tube for attachment to a receptacle adapted to hold a fluent therapeutic susceptible to deterioration on exposure to gas such as oxygen or carbon dioxide. The transfer tube has a tubular body having a proximal end, a distal end opposite the proximal end, a flow passage extending between said proximal and distal ends adapted to communicate with said receptacle, and a closure blocking flow through the flow passage and adapted to be pierced by a tubular needle for transfer of therapeutic through the needle. The tubular body and closure are essentially impermeable to said gas.
The present invention is also directed to a needle holder for application to the distal end of a transfer tube of a receptacle particularly adapted to hold a fluent therapeutic 10 susceptible to deterioration on exposure to gas such as oxygen or carbon dioxide. The needle holder is adapted to hold in place the carrier of a transfer needle with the needle piercing the transfer tube. The holder has a body having a first annular wall defining a first cavity at a first end of the body, a second annular wall defining a second cavity at a second end of the body, and a flow passage extending between the two cavities, the first annular wall being sized for an interference fit with said transfer tube to releasably attach the needle holder to the transfer tube, and the second annular wall being sized for an interference fit with said needle carrier to releasably attach the needle carrier to the needle holder in a position in which needle is disposed in said flow passage.
Additional features, advantages, and other aspects and attributes of the present invention will be discussed with reference to the following drawings and accompanying specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 a is a plan view of a flowable materials receptacle and closure system;
FIG. 1 b is a cross-sectional view taken along line b-b of FIG. 1 a;
FIG. 1 c is a plan view of a flowable materials receptacle having a fill port and an administration port;
FIG. 2 a is a cross-sectional view of a three-layer tubing;
FIG. 2 b is a cross-sectional view of a two-layer tubing;
FIG. 3 a is a cross-sectional view of a two-layer membrane film;
FIG. 3 b is a cross-sectional view of a three-layer membrane film;
FIG. 3 c is a cross-sectional view of a five-layer membrane film;
FIG. 4 is a cross-sectional view of a membrane film and tube assembly;
FIG. 5 is a side view of a needle or “spike” holder;
FIG. 6 is cross-sectional view of the spike holder of FIG. 6 ;
FIG. 7 is an cross-sectional view taken along line A-A of FIG. 6 ;
FIG. 8 is an assembly of the membrane film and tube assembly with the spike holder or needle holder of FIG. 5 with a spike being introduced therein; and
FIG. 9 is a cross-sectional view of a four-layer membrane film.
DETAILED DESCRIPTION OF THE INVENTION
While this invention is susceptible of embodiments in many different forms, there is shown in the drawings and will herein be described in detail preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated.
FIG. 1 a shows a flowable materials receptacle and closure system generally referred to as 10 . The system includes a flowable materials receptacle 30 , a port (transfer) tube and closure assembly 40 , and a needle or “spike” holder 50 . The relative size of the receptacle 30 , assembly 40 , and spike holder 50 are exaggerated for illustrative purposes. In a preferred form of the invention, the system 10 is useful for containing and delivering a fluent therapeutic susceptible to deterioration on exposure to a gas such as oxygen or carbon dioxide. The system is also particularly well suited for storage and delivery of a buffered solution.
What is meant by “flowable material” is a material that will flow by the force of gravity. Flowable materials therefore include both liquid items and powdered or granular items and the like. Flowable materials receptacles find particular use for storage and delivery of medical or therapeutic fluids and include, but are not limited to, I.V. receptacles, peritoneal dialysis drain and fill receptacles, blood receptacles, blood product receptacles, blood substitute receptacles, nutritional receptacles, food receptacles and the like.
FIGS. 1 a and 8 illustrate the assembly 40 as including a port (transfer) tube 52 and a closure in the form of a wall or membrane 54 . The port tube 52 defines a fluid flow passage 56 and has an end surface 58 . The membrane 54 is shown attached to the port tube end surface 58 . It is contemplated by the present invention the membrane 54 could also be positioned inside the port tube flow passage 56 without departing from the scope of the present invention.
While it is contemplated the port tube 52 can have any number of layers, in a preferred form of the invention the port tube 52 will include either a discrete layer of a barrier material or a blend layer including a barrier material. The barrier material will present a barrier to the passage of gasses or water vapor transmission, and, in a preferred form of the invention, will reduce the passage rate of oxygen therethrough. It is also desirable that all materials in the solution contact layer, and more preferably all materials used in the tubing, be free of halogens, plasticizers or other low-molecular weight or water soluble components that can leach out into the solutions transferred through the tubing. Suitable barrier materials include ethylene vinyl alcohol copolymers having an ethylene content of from about 25% to about 45% by mole percent, more preferably from about 28% to about 36% by mole percent and most preferably from about 30% to about 34% by mole percent.
In an even more preferred form of the invention, the port tube 52 will have multiple layers. FIG. 2 a and FIG. 2 b show respectively a three-layer port tube 52 and a two-layer port tube. The three-layer port tube 52 has an outside or an outermost layer 60 , a core layer 62 and an inside solution contact layer 64 . Similarly, the two-layer port tube 52 has an outside layer 60 and an inside, solution contact layer 64 .
In a preferred form of the invention, the multiple layer transfer tube or port tube 52 will have a discrete layer of a barrier material with the remaining layers being selected from polyolefins. The layers of the tube can be positioned in any order, however, in a preferred form of the invention, the barrier layer is not positioned as the outside layer 60 . Thus, the layers of a three layer tube can be positioned in one of six orders selected from the group: first/second/third, first/third/second, second/first/third, second/third/first, third/first/second, and third/second/first. Further, in tube embodiments having more than two layers, the tube 52 can be symmetrical or asymmetrical from a material aspect and from a thickness of layers aspect.
Suitable polyolefins include homopolymers, copolymers and terpolymers obtained using, at least in part, monomers selected from α-olefins having from 2 to 12 carbons. One particularly suitable polyolefin is an ethylene and α-olefin interpolymer (which sometimes shall be referred to as a copolymer). Suitable ethylene and α-olefin interpolymers preferably have a density, as measured by ASTM D-792 of less than about 0.915 g/cc and are commonly referred to as very low density polyethylene (VLDPE), ultra low density ethylene (ULDPE) and the like. The α-olefin should have from 3-17 carbons, more preferably from 4-12 and most preferably 4-8 carbons. In a preferred form of the invention, the ethylene and α-olefin copolymers are obtained using single site catalysts. Suitable single site catalyst systems, among others, are those disclosed in U.S. Pat. Nos. 5,783,638 and 5,272,236. Suitable ethylene and α-olefin copolymers include those sold by Dow Chemical Company under the AFFINITY trademark, Dupont-Dow under the ENGAGE trademark and Exxon under the EXACT and PLASTOMER trademarks.
The polyolefins also include modified polyolefins and modified olefins blended with unmodified olefins. Suitable modified polyolefins are typically polyethylene or polyethylene copolymers. The polyethylenes can be ULDPE, low density (LDPE), linear low density (LLDPE), medium density polyethylene (MDPE), and high density polyethylenes (HDPE). The modified polyethylenes may have a density from 0.850-0.95 g/cc. The polyethylene may be modified by grafting or otherwise chemically, electronically or physically associating a group of carboxylic acids, and carboxylic acid anhydrides. Suitable modifying groups include, for example, maleic acid, fumaric acid, itaconic acid, citraconic acid, allylsuccinic acid, cyclohex-4-ene-1,2-dicarboxylic acid, 4-methylcyclohex-4-ene-1,2-dicarboxylic acid, bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid, x-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid, maleic anhydride, itaconic anhydride, citraconic anhyride, allylsuccinic anhydride, citraconic anhydride, allylsuccinic anhydride, cyclohex-4-ene-1,2-dicarboxylic anhydride, 4-methylcyclohex-4-ene-1,2-dicarboxylic anhydride, bicyclo[2.2.1]hept-5-ene2,3-dicarboxylic anhydride, and x-methylbicyclo[2.2.1]hept-5-ene-2,2-dicarboxylic anhydride.
Examples of other modifying groups include C 1 -C 8 alkyl esters or glycidyl ester derivatives of unsaturated carboxylic acids such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, glycidyl acrylate, glycidal methacrylate, monoethyl maleate, diethyl maleate, monomethyl maleate, diethyl maleate, monomethyl fumarate, dimethyl fumarate, monomethyl itaconate, and diethylitaconate; amide derivatives of unsaturated carboxylic acids such as acrylamide, methacrylamide, maleicmonoamide, maleic diamide, maleic N-monoethylamide, maleic N,N-diethylamide, maleic N-monobutylamide, maleic N,N dibutylamide, fumaric monoamide, fumaric diamide, fumaric N-monoethylamide, fumaric N,N-diethylamide, fumaric N-monobutylamide and fumaric N,N-dibutylamide; imide derivatives of unsaturated carboxylic acids such as maleimide, N-butymaleimide and N-phenylmaleimide; and metal salts of unsaturated carboxylic acids such as sodium acrylate, sodium methacrylate, potassium acrylate and potassium methacrylate. More preferably, the polyolefin is modified by a fused ring carboxylic anhydride and most preferably a maleic anhydride.
The polyolefins also include ethylene vinyl acetate copolymers, modified ethylene vinyl acetate copolymers and blends thereof. The modified EVA has an associated modifying group selected from the above listed modifying groups.
In one preferred form of the invention, the tube 52 has a solution contact layer 64 of a modified EVA copolymer sold by DuPont Packaging under the trademark BYNEL® CXA, a core layer 62 of an EVOH and an outside layer 60 of a modified EVA, again preferably CXA. Such a structure is symmetrical from a materials standpoint. According to a preferred form of the invention, such tubing will have layers of the following thickness ranges: outside layer 60 from about 0.002 inches to about 0.042 inches, preferably about 0.010 inches, the core layer 62 from about 0.016 inches to about 0.056 inches, preferably about 0.039 inches, and the solution contact layer 64 of from about 0.002 inches to about 0.042 inches, preferably about 0.010 inches.
In another preferred form of the invention, the tube 52 has a solution contact layer 64 of an EVOH, a core layer 62 of a modified EVA and preferably BYNEL® CXA and an outside or outermost layer 60 of an ethylene and α-olefin copolymer. Such a structure is symmetrical from a materials standpoint. The tube layers can have various relative thicknesses. According to a preferred form of the invention, tube 52 will have layers of the following thickness ranges: outside layer 60 from about 0.002 inches to about 0.042 inches; the core layer 62 from about 0.002 inches to about 0.042 inches; and the solution contact layer 64 from about 0.016 inches to about 0.056 inches. The outermost layer 60 of EVA is well suited for bonding to the transfer tube, especially upon heat sealing.
In a further preferred form, the tube 52 has a solution contact layer 64 of BYNEL® CXA, a core layer 62 of EVOH, and an outside layer 60 of a blend of 50% ULDPE and 50% CXA. Such tubing will have layers of the following thickness ranges: outside layer 60 from about 0.002 inches to about 0.042 inches, preferably about 0.010 inches; the core layer 62 from about 0.016 inches to about 0.056 inches, preferably about 0.039 inches; and the solution contact layer 64 of from about 0.002 inches to about 0.042 inches, preferably about 0.010 inches.
In a preferred form of the invention, the port tube 52 shall have the following dimensions: inside diameter from about 0.100 inches to about 0.500 inches and the wall thickness shall be from about 0.020 inches to about 0.064 inches. The port tube 52 can be prepared by injection molding, extrusion, coextrusion or other polymer processing techniques well known in the art.
Turning our attention now to the closure 54 , the membrane film forming the closure 54 can have any number of layers, but in a preferred form of the invention has multiple layers. The membrane film 54 , in a preferred form of the invention, shall have a barrier layer as defined above. FIG. 3 a shows a two-layer structure 54 having an outside layer 72 and an inside layer 70 . FIG. 3 b shows a three-layer structure 54 having an outside layer 72 , an inside layer 70 and a core layer 74 . FIG. 3 c shows a five-layer structure 54 having an outside layer 72 , an inside layer 70 , a core layer 74 , and two tie layers 76 . In a preferred form of the invention, one layer shall be of a barrier material defined above and the remaining layer or layers shall be selected from the polyolefins defined above, polyamides and polyesters. One of the inside layer 70 or outside layer 72 shall define a tubing contact layer or seal layer.
Suitable polyamides include those obtained from a ring-opening reaction of lactams having from 4-12 carbons. This group of polyamides therefore includes, but is not limited to, nylon 6, nylon 10 and nylon 12.
Acceptable polyamides also include aliphatic polyamides resulting from the condensation reaction of di-amines having a carbon number within a range of 2-13, aliphatic polyamides resulting from a condensation reaction of di-acids having a carbon number within a range of 2-13, polyamides resulting from the condensation reaction of dimer fatty acids, and amide containing copolymers. Thus, suitable aliphatic polyamides include, for example, nylon 66, nylon 6,10 and dimer fatty acid polyamides.
Suitable polyesters include polycondensation products of di- or polycarboxylic acids and di or poly hydroxy alcohols or alkylene oxides. Preferably, the polyesters are a condensation product of ethylene glycol and a saturated carboxylic acid such as ortho or isophthalic acids and adipic acid. More preferably the polyesters include polyethyleneterephthalates produced by condensation of ethylene glycol and terephthalic acid; polybutyleneterephthalates produced by a condensations of 1,4-butanediol and terephthalic acid; and polyethyleneterephthalate copolymers and polybutyleneterephthalate copolymers which have a third component of an acid component such as phthalic acid, isophthalic acid, sebacic acid, adipic acid, azelaic acid, glutaric acid, succinic acid, oxalic acid, etc.; and a diol component such as 1,4-cyclohexanedimethanol, diethyleneglycol, propyleneglycol, etc. and blended mixtures thereof.
In a preferred form of the invention, the membrane structure shall have five layers as shown in FIG. 3 c and is described in detail in commonly assigned U.S. Pat. No. 6,083,587 which is incorporated herein by reference and made a part hereof. The outside layer 72 is a polyamide and preferably nylon 12, the two tie layers 76 are a modified EVA copolymer, the core layer 74 is an EVOH and the inner layer 70 is a modified EVA. In a preferred form of the invention the inside layer 70 defines the tubing contact layer.
Further, the structure shown in FIG. 3 c has the following layer thickness ranges: outside layer 72 from about 0.0005 inches to about 0.003 inches; the tie layers 76 from about 0.0005 inches to about 0.02 inches; the core layer 74 of from about 0.0005 inches to about 0.0015 inches; and an inside layer 70 of from about 0.008 inches to about 0.012 inches.
In another preferred form, the membrane structure has four layers as shown in FIG. 9 . FIG. 9 shows a membrane 126 having an outer layer 128 of a polyamide, preferably nylon and more preferably a nylon 12, a third layer 130 of a modified ethylene vinyl acetate, preferably CXA, a second layer 132 of a barrier material, preferably EVOH, and an inner solution contact layer 134 of a modified ethylene vinyl acetate, preferably CXA.
The outer layer 128 has a thickness of a range of about 0.0003 to 0.0007 inches, and preferably about 0.0005 inches. The third layer 130 has a thickness range of between 0.0003 to 0.0007 inches, and preferably about 0.0005 inches. The second layer 132 has a thickness range of between 0.0007 to 0.0013 inches, and preferably about 0.001 inches. The inner layer 134 has a thickness of between 0.006 and 0.01 inches, and preferably about 0.008 inches. The membrane film can be formed by extrusion, coextrusion, lamination, extrusion coating, or other polymer processing technique well known in the art.
Turning our attention now to the receptacle 30 ( FIGS. 1 a , 1 b and 1 c ). In a preferred form of the invention the receptacle 30 is of a polymeric material or structure and more preferably includes a barrier material as an additive to a layer or as a discrete barrier layer as defined above. In a preferred form of the invention, the receptacle has sidewalls 80 which are positioned in registration and sealed along a peripheral seam 82 . The sealing can be carried out by conductive heat sealing or inductive heat sealing such as through radio frequency sealing or can be sealed by other methods well known in the art. The peripheral seam 82 , preferably, has an outer seal 84 , an inner seal 86 and a material depot 88 positioned therebetween. One or more access or administration ports 89 can be provided as is well known in the art. In a preferred form of the invention the receptacle can have a fill port 89 ′ on one end of the container and a administration port 89 on an opposite end of the container. The administration port can be the closure assembly 40 described above. The fill port 89 ′ can have the same structure as the administration port or, in a more preferred form of the invention, will be of a polyolefin material, a polyolefin blend or one of the other materials set forth above but will not include the gas barrier material of the administration port. The fill port 89 ′ can be removed after filling the container by a hot knife or during a step of sealing the container after filling. The material depot 88 defines an unsealed portion where material from the seals 84 and 86 can flow. The sidewalls 80 define a fluid containing chamber 90 . The fluid chamber is capable of storing flowable materials and more preferably is capable of forming a fluid tight seal. The receptable and closure assembly will preferably have an oxygen permeability of less than 0.10 cc/day, more preferably less than 0.075 cc/day and most preferably less than 0.04 cc/day, or any range or combination of ranges therein.
In a preferred form of the invention, the sidewalls 80 are of a multiple layer structure and can include the material structures as shown in FIGS. 3 a to 3 c and the description set forth above for these structures. In a preferred form of the invention, the sidewall 80 has five layers. The structure is the same as that disclosed in FIG. 3 c but includes an additional layer outward from inside layer 70 . The inner layer is preferably a polyolefin and more preferably an ethylene and α-olefin copolymer. The relative thicknesses of the layers is fully set forth in U.S. Pat. No. 6,083,587 at column 5, line 64 through column 6, line 8.
The receptacle 30 shall have the following physical properties: modulus of elasticity of the sidewall of the receptacle is less than 60,000 psi and more preferably less than 40,000 psi; is suitable of storing an oxygen sensitive composition for at least about 6 months, more preferably at least about 1 year, more preferably at least about 2 years and even more preferably at least about 3 years; is capable of achieving these storage periods at temperatures of about room temperature and more preferably from 5° C. to about 45° C.
Turning our attention now to FIG. 4 showing a port tube/closure assembly 40 . The assembly 40 preferably is constructed without the use of solvents or adhesives. The assembly 40 has one of the closure 54 described above formed into a disk shape and attached to the port tube end surface 58 . The closure can also be attached inside the port tube flow passage 56 . The closure 54 can be placed in contact with the end surface 58 of the port tube and attached thereto using conductive heat sealing, inductive heat sealing (such as using radio frequency energies), ultrasonic welding, vibration welding, or other techniques well known in the art.
It should be understood that a port tube 52 having any of the constructions described above can be combined with a closure 54 having any of the constructions described above. Thus, an assembly of a port tube 52 having any number of layers and a closure 54 having two layers, three layers or more is contemplated by the present invention. It is also contemplated that a port tube 52 having two layers, three layers or more could be combined with a membrane film 54 having any number of layers.
The spike holder 50 (which also may be referred to as a needle holder) is shown in FIGS. 1 a , and 5 - 8 . The spike holder 50 has a body 100 having a first annular wall defining a first cavity or chamber 110 at a first end of the body, a second annular wall defining a second cavity or a second chamber 112 at a second end of the body, and a flow passage 114 connecting the first and second chambers. The first chamber 110 is dimensioned to telescopically receive an end portion 116 of the port tube 52 . In a preferred form of the invention the spike holder is fixedly attached to the port tube but could be releasably attached without departing from the scope of the present invention. It is contemplated by the present invention the annular wall could extend into the port tube flow passage 56 and attach thereto without departing from the present invention. The second chamber 112 is dimensioned to have an interference fit with an access spike or transfer needle 117 described below. As noted herein, the term interference fit means that the second chamber 112 has an identical or smaller dimension than the spike holders inserted therein but is capable of deforming (e.g., elastically) around the insert to hold the inserted device by friction. It is contemplated the second chamber 112 will fixedly attach to the insert or releasably attach to the insert. In a preferred form of the invention, the first chamber 110 and the second chamber 112 have a generally circular cross-sectional shape, the first chamber 110 having a first diameter and the second chamber 112 having a second diameter, the first diameter being larger than the second diameter.
In a preferred form of the invention, the spike holder 50 has an outwardly extending flange 118 at an intermediate portion thereof. The flange 118 is positioned generally at the intersection of the first chamber 110 and the second chamber 112 . The flange 118 has a first surface 120 which is textured to facilitate handling and manipulation of the holder. In one embodiment, this texture is provided by a plurality of buttresses 122 around the first annular wall of the body 100 . In a preferred form of the invention, the flange 118 is generally circular in cross-sectional shape and the buttresses 122 are circumferentially spaced about the first surface 120 . The buttresses are shown having a generally tear-drop shape, however, they could be of numerous different shapes without departing from the present invention. The buttresses are provided to form a gripping surface for those handling the spike holder 50 . It may also be desirable to add an internal shoulder or other feature to the spike holder 50 to limit the extent the transfer tube can be inserted into the flow passage.
The spike holder 50 is formed from a polyolefin as defined above and more particularly is an ethylene and α-olefin copolymer. The spike holder 50 can also have a textured or matte finish on a portion or the entire outer surface 124 of the holder 50 for ease of handling. The spike holder 50 can be formed by any suitable polymer forming technique known to those skilled in the art and preferably the spike holder 50 is formed by injection molding. The spike holder 50 can also include a membrane film 54 ′ positioned in the passageway 114 in lieu of or in addition to the membrane 54 .
In a preferred form of the invention, the spike holder 50 is formed directly over the end portion 116 of the port tube/membrane film assemblies 40 described above. Such a process is conventional and referred to as an overmolding process. The overmolding process includes the steps of: (1) providing a tubing as set forth above; providing a mold for forming a spike holder; inserting a portion 116 of the tubing 52 into the mold; and supplying polymeric material to the mold to form a spike holder on the tubing.
In an embodiment of the invention, the tubing, closure, and/or container sidewalls are comprised of a multilayer polymeric structure which includes a first layer of an ethylene vinyl alcohol copolymer having first and second sides, and a second layer of a modified ethylene vinyl acetate copolymer attached to the first side of the first layer. The second layer has a thickness of greater than 1.2 mils, preferably at least 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, or 3.0 mils. The polymeric structure optionally includes a third layer attached to the second side of the first layer. Preferably, the third layer comprises a polyamide or polyester as described herein. In one embodiment, the sidewalls of a container include a core layer, outside layer, or solution contact layer comprising a modified ethylene vinyl acetate copolymer as described herein. In another embodiment, the polymeric structure comprises an outside layer of a polyamide or polyester, a core layer of an ethylene vinyl alcohol copolymer, and a sealing layer of a modified ethylene vinyl acetate copolymer, wherein the core layer is between the outside and sealing layers. This polymeric structure optionally includes one or more tie layers attached to the core layer.
The receptacles of the present invention are used to store deoxyhemoglobin solutions or other therapeutic fluids which react with oxygen. The receptacles are filled with the solution in a low oxygen or oxygen free environment, sealed, and then stored at about 5 to 45° C. for weeks or months prior to use. Conventional methods of filling and sealing containers in a low oxygen or oxygen free environment are suitable for the invention. After storage, the deoxyhemoglobin solution contains less than 15% methemoglobin and is physiologically acceptable for administration to a patient. In a preferred embodiment, the deoxyhemoglobin solutions are stored at room temperature and ambient conditions.
The following is an example of the present invention and is not intended to limit the claims of the present invention.
EXAMPLE
Several 250 ml volume receptacles were fabricated as shown in FIG. 1 c with a fill port and an administration port. Each receptacles had a total nominal surface area of approximately 450 cm 2 . The administration port had a core layer of an EVOH and an outside layer of a modified EVA (CXA) and a solution contact layer of a modified EVA (CXA). A membrane film was sealed to a distal end of the administration port. The membrane had an outer layer 134 of nylon 12, a third layer 130 of a modified ethylene vinyl acetate (CXA), a second layer 132 of EVOH, and an inner solution contact layer 128 of a modified ethylene vinyl acetate (CXA) (see FIG. 9 ). The fill port was injection molded of ethylene vinyl acetate (EVA). The receptacle sidewalls were fabricated from a five-layer structure as shown in FIG. 3 c . An outside layer 72 was nylon 12, two tie layers 76 were a modified EVA copolymer (CXA), a core layer 74 was an EVOH and the inner layer 70 was a metallocene catalyzed ultra low density polyethylene. The empty containers were sterilized by exposure to gamma radiation. The sterile containers were aseptically filled with an oxygen sensitive indicator solution through the fill port and the fill port was sealed and removed by a heated bar. The oxygen permeability of the containers were measured at 70% relative humidity at temperatures of 4° C., 23° C. and 40° C. and found to be 0.0008, 0.0041, and 0.0396 cc/day/package, respectively.
It is understood that, given the above description of the embodiments of the invention, various modifications may be made by one skilled in the art. Such modifications are intended to be encompassed by the claims below. | The present invention provides a receptacle ( 30 ) for a therapeutic fluid susceptible to deterioration on exposure to a gas such as oxygen or carbon dioxide. The receptacle ( 30 ) has walls of sheet material each including at least one layer forming a barrier essentially impermeable to such gas, and a seal sealing the walls together in a region thereof. A transfer tube ( 40 ) is sealed in the seal having a proximal end in the receptacle ( 30 ), a distal end accessible from outside the receptacle ( 30 ), a flow passage ( 56 ) extending between said proximal and distal ends, and a closure ( 54 ) blocking flow through the flow passage ( 56 ) adapted to be pierced by a tubular needle for transfer of therapeutic through the needle. The transfer tube ( 40 ) and closure ( 54 ) are essentially impermeable to said gas. | 8 |
BACKGROUND OF THE INVENTION
The invention relates to an electromagnetic patterning system of the class defined in the generic part of claim 1.
Patterning systems of this kind operate on the principle of using electromagnetic means to shift or swing the control elements associated individually with the knitting tools into one of at least two positions in accordance with a pattern. This process, referred to as "sorting the control elements," is necessary in order to bring the knitting tools at a later point in time, and in relation to the position of the control elements, into a knit or missknit position, for example. To avoid having to provide each individual control element with its own electromagnetic patterning system, it is common practice to provide only one patterning system on each knitting system of the knitting machine and to perform the sorting of the control elements either by moving the control elements past the parts of the patterning system which produce the sorting, or, vice versa, by moving the parts which produce the sorting past the control elements. This relative movement is produced, for example, by the rotation of the needle cylinder of a circular knitting machine or the motion of the slide of a flat knitting machine.
There are essentially two possibilities for performing the sorting. The one possibility (German Fed. Pat. 12 69 762) consists in performing the swinging or shifting of the control elements by purely electromagnetic means. This is accomplished, for example, by providing an electromagnetic control pole with a pole face disposed transversely of the direction of the relative movement, which leaves the control elements that run past it either in their current position or pulls them by a defined, even through small amount, to a position different from their current position. According to the other possibility (German Fed. Pat. 15 85 211), however, the shift or swing of the control elements is achieved by mechanical means, for example in that a resiliently biased spring rod is either held by magnetic force or swung by sprung force in the area of the control pole.
These and all comparable electromagnetic patterning system have it in common that the sorting of the control elements i.e., their shifting or swinging to one of the two positions, must take place while the control elements are moving past the control pole. As a rule, holding poles are also provided which follow the control pole in the direction of movement, but their purpose is only to intensify the sorting started in the area of the control poles, i.e., to increase the distances between the control elements in the one or the other position. It follows that the electrical signals fed to the control poles must last at least long enough for the control elements to be shifted or swung by the necessary amount, and that the reliability of the sorting is all the poorer as the relative velocity between the control elements and the control poles is greater and the distance between the individual control elements is smaller. Moreover, control or holding poles with comparatively greater power are needed, and this is undesirable not only for reasons of power consumption, but also because it results in the danger that the control or holding poles will act not only on the control element that is to be selected but also on at least one adjacent control element, thereby impairing reliability of operation.
It is the object of the invention to improve the patterning system of the kind defined above such that it will operate faster, be less liable to trouble, and operate with less powerful control poles or holding poles.
This is to be achieved by making the duration of the excitation of the control poles independent of the swinging or shifting movements of the control elements.
THE INVENTION
The distinctive features of claim 1 are provided for the achievement of this object.
Additional advantageous features of the invention will be found in the subordinate claims.
The invention brings with it a number of advantages. The control elements are provided at the location of the electromagnetic control pole only with an address in the form of a magnetic north or south pole, i.e., they are neither swung nor shifted transversely of the direction of the relative movement. The addresses imparted to the control elements by the control pole are retained, even when the control elements again leave the control pole, and they can then be utilized, at any distance from the control pole, for performing a sort, i.e., shifting or swinging of the control elements, by means of at least one magnetic holding pole which is in the form of a magnetic north or south pole. On the basis of this kind of control, the holding poles do not have to be disposed immediately following the control poles. Furthermore, the control poles need to be excited only for as long as is necessary for the reliable magnetization of the control elements moving past them. This length of time is substantially shorter than the excitement time required in patterning systems of the prior art. Lastly, control poles of comparatively low power can be used, because the magnetic field strengths required for the magnetization of the control elements are lower than the field strengths necessary for the pulling or compensation of the prior-art control elements.
The invention will be further explained hereinbelow through embodiments in conjunction with the appended drawing.
DESCRIPTION OF THE DRAWINGS
FIGS. 1 to 5 show diagrammatically five embodiments of the system according to the invention;
FIGS. 6 and 7 show the cross section and the plan view of an addressing magnet for the patterning system according to FIGS. 1 to 5;
FIG. 8 shows a plan view of a sorting magnet for the patterning system according to FIGS. 1 to 5;
FIGS. 9 and 10 show sections along line IX--IX of FIG. 8 for differently magnetized control elements;
FIG. 11 shows a second embodiment of the sorting magnet;
FIG. 12 shows the hysteresis curve of a control element for patterning system according to FIGS. 1 to 5;
FIG. 13 shows the development of a segment of the cam periphery of a circular knitting machine having a patterning system according to FIG. 2, wherein the cam tracks needed for knitting are shown in the left view and those needed for missknitting are shown in the bottom half;
FIGS. 14 and 17 represent enlarged sections along lines A--A, B--B, C--C and D--D through the portion of the cam periphery which has a patterning system according to FIG. 2 and a portion of the needle cylinder of the circular knitting machine,
FIGS. 18 to 24 are sections taken along lines A--A and D--D to I--I of FIG. 13; they are similar to FIGS. 14 to 17, but correspond in scale to FIG. 13; and
FIGS. 25 to 28 a prefered embodiment of this invention in similar to FIGS. 1, 14, 15 and 17.
DESCRIPTION OF PREFERRED EMBODIMENTS
In each of FIGS. 1 to 5, there is shown in plan a plurality of control elements 1 which, in accordance with FIG. 6, consist of a ferromagnetic rod or spring wire having a circular cross section and a diameter of about 0.5 mm. The points represented in solid black in FIGS. 1 to 5 mean that the control elements 1 have at their visible end a residual or remanent magnetic north pole, while the control elements 1 represented as circles have at their visible end a residual or remanent magnetic south pole. Each of the control elements 1, as it will be explained later on, is associated with a knitting tool, e.g., a needle, a jack, a sinker or a plush hook or sinker or the like, and moves in the direction of the arrow in FIGS. 1 to 5, i.e., from left to right.
According to FIG. 1, the control elements coming from the left are divided into two positions, the upper position I, for example, signifying that the corresponding knitting tools in a preceding knitting system have performed a knit, while the lower position II corresponds to a previous non knit or missknit. Before arriving at the knitting system that is next in the direction of the arrow, the control elements of position I first run onto a cam piece or lobe 2 by which they are swung or shifted transversely of their direction of movement to the position II. In this position II, the address sections 3 of all the control elements (FIG. 6) run directly past an addressing pole 4 of an addressing magnet 5. According to FIG. 6, the addressing magnet 5 consists, for example, of a U-shaped core 6 of soft iron around which a coil 7 is wound. The two free ends of the core 6 constitute controllable poles in the form of addressing poles, namely the addressing pole 4 and an additional addressing pole 8 which, when the control elements 1 pass by, can act upon an additional address section 9 thereof. If current is made to flow through the coil 7 in the one direction by the application of an electrical signal, the addressing pole 4 is a magnetic north pole, for example, while at the same time the addressing pole 8 is a magnetic south pole. In the opposite direction of the current, the addressing pole 4 is accordingly south-magnetic, but addressing pole 8 is northmagnetic, as it is assumed in FIG. 6 and indicated by the letters "N" and "S", respectively. The assumed polarization has the result that the control element 1 is magnetized oppositely, i.e., the address section 3 becomes a magnetic north pole (therefore represented in solid black in figure 6), while the address section 9 becomes a magnetic south pole.
On account of the remanence of the ferromagnetic material, the information is kept stored in the address sections 3 and 9 in the form of north or south poles, when the control elements 1 move on to emerge from the range of action of the addressing magnets 5 and approach a sorting magnet 10. The latter contains a permanent sorting pole 11 in the form of a south pole on the one side, and a permanent sorting pole 12 in the form of a north pole on the other side of the path of movement of the control elements 1, both sorting poles 11 and 12 being disposed at the level of the address sections 3. The sorting pole 11 can, according to FIGS. 8 to 10, also consist of the one end of a bar pole shoe 14, whose other end is joined to the one pole of a permanent magnet 15 whose other pole is engaged with one end of another bar pole shoe 16 which forms with its opposite end an additional sorting pole 17 situated at the level of the addressing sections 9. Accordingly, the sorting pole 12 can be the one end of a bar pole shoe 18 which is combined with an additional bar-shaped pole shoe 20 having a sorting pole 19, and with a permanent magnet 21, to form an additional horseshoe magnet.
The ends of the pole shoes 18 and 20 which have the sorting poles 12 and 19 extend, according to FIGS. 1 and 8, substantially parallel to the direction of movement of the control elements 1 entering position II and the immediate vicinity thereof, and they can have a entry ramp 22 at the entry end. The ends of pole shoes 14 and 16 which have the sorting poles 11 and 17, however, are convexly curved transversely of the path of movement of the control elements 1 and are arranged such that they first form an entry funnel with the entry ramp 22, then confront one another at a distance corresponding substantially to the diameter of the control elements 1, and finally, in the manner of an exit funnel, they are at a constantly increasing distance from the sorting poles 12 and 19 across the path of movement of the control elements. The control elements 1 are therefore brought by the entry funnel at first close to the sorting poles 11, 12, 17 and 19, and then, depending on the polarization of their address sections 3 and 9, they are repelled by sorting poles of like polarity and attracted by sorting poles of different polarity, as indicated in FIGS. 9 and 10 for the two possible addresses. Thus, the control elements provided with a south magnetic address section 3 remain in position II after leaving the sorting magnets 10, while the control elements 1 provided with a north magnetic address section 3 are deflected transversely of their direction of movement. As soon as their distance from the control elements remaining in position II is sufficiently great, the deflected control elements run onto a cam 23 of a nonmagnetic material extending into the exit funnel of the sorting magnet 10, and are steered thereby into position I. The control elements 1 separated in this manner then remain in the positions I and II represented in the left portion of FIG. 1 until they enter the next-following knitting system, where they will again be sorted according to the pattern.
As shown especially in FIGS. 9 and 10, for the sorting of the control elements 1 into one or the other positions, which is performed by means of the sorting magnets, that is, to the one or the other side of the cam 23, it matters not whether the sorting magnet 10 acts on only one of the address sections 3 or 9 or on both address sections 3 and 9 of the control elements 1. In principle, it would suffice to have the sorting magnet 10 act on only one of the two address sections 3 or 9 and to close the lines of force of the control element 1 through the air, by having two permanent magnets 24, represented in FIG. 11, acting only on the address sections 3.
The invention is thus based on the idea of addressing the control elements 1 in the area of the addressing magnet 5 in at least one active address section 3, i.e., of making them north magnetic or south magnetic, and of sorting them according to their particular addresses in the area of a sorting magnet 10 disposed behind the addressing magnet 5 in the direction of movement. This principle requires that the magnetic field strengths developed by the sorting magnet 10 be lower than the coercivity of the control elements 1 in the area of the address sections, so that none of the sorting poles can cause any remagnetization of the address sections and hence an erasure or falsification of the stored information, and furthermore that the remanence in the area of the address sections be sufficiently great, since otherwise, in view of the common tolerances, the forces that could be exercised by the sorting poles on the control elements could not be as great as is necessary for their reliable sorting into one or the other position. Lastly, it is to be noted, however, that the coercivity should not be so great that appreciable magnetic field strengths are required for the reverse magnetization of the address sections, because this is undesirable for energy reasons on the one hand, and on the other hand it might have undesirable effects on the control elements that are immediately adjacent to control elements that are to be addressed.
So-called semihard magnetic materials, whose hysteresis curve is represented in FIG. 12, have proven to be suitable for the purposes of the invention, Therein, the field strengths needed for the magnetization are recorded along the abscissae in amperes per centimeter, and the polarization obtained is recorded along the ordinates in teslas. From FIGS. 12 it is apparent that the coercivity, starting out from the saturation level, is approximately 50 amperes per centimeter, while the remanence, also starting out from saturation, amounts to about 1.5 teslas. These values are well suited for addressing and sorting a rod or spring wire consisting of this material, several centimeters long and about 0.5 mm thick in the manner represented in FIG. 1.
In the embodiment according to FIG. 1, current must flow in one or the other direction through the coil 7, for the reverse magnetization of the address sections 3 and 9 in accordance with the pattern. In the embodiment according to FIG. 2, this is avoided by disposing ahead of the addressing pole a permanent north or south magnetic biasing pole 26 which is, for example, a portion of a biasing magnet 27 and can be part of a horseshoe magnet represented in FIGS. 9 and 10. The biasing pole 26 is to reverse-magnetize the address sections 3 or 9 so that, regardless of which polarization they have before reaching the biasing pole 26, they will leave the latter with a certain, always equal premagnetization (bias). The magnetic field strength developed by the biasing pole 26 is therefore greater than the coercivity of the address sections 3 and 9. In the case of the example in FIG. 2, it is assumed that the biasing pole 26 is a south pole, so that all control elements 1 leaving it have been polarized north-magnetic in the associated addressing section 3, as the solid black dots indicate. Therefore no control signal is fed to the coil 7 if the address is to remain north-magnetic, while it is fed with a signal of a certain direction if reverse magnetization to a south pole is desired. In contrast to FIG. 1, therefore, only signals of types "O" or "L" are needed, instead of types "+L" and "-L."
As an additional difference from FIG. 1, in the embodiment according to FIG. 2 a sorting magnet 28 is provided, which has at least two confronting sorting poles 29 and 30, both of which are of convex configuration transversely of the path of movement of the control elements 1. This brings it about that the control elements 1 are deflected, depending on their polarization, both by the sorting pole 29 and by the sorting pole 30, transversely of their direction of movement. In this case the sorting poles 29 and 30 are best made so long that the associated control elements 1 exit into the positions I and II, respectively, so that a cam corresponding to cam 23 (FIG. 1) can be omitted. On the other hand, it is necessary,in contrast to FIG. 1, to provide ahead of the biasing pole 26 two cams 31 and 32 in order to shift or swing the control elements distributed to positions I and II into a basic position situated between these two positions I and II. In this basic position the control elements 1 then move past the biasing pole 26 and the addressing pole 4 to the entry funnel of the sorting magnet 28.
In the embodiment according to FIG. 3, a biasing magnet 34 is provided with a biasing pole 35 which is configured convexly across the path of movement of the control elements 1, and is disposed such that both the control elements 1 that are in position I and those in position II run against it and they are all swung or shifted to position II by the extremity at the exit side of the biasing coil 34. From there on, the addressing and sorting corresponding to those according to FIG. 1.
The embodiment according to FIG. 4 differs from that of FIG. 3 only in the construction of the sorting magnet 36. The latter contains a sorting pole 37 that is convexly curved transversely of the direction of movement, and which begins at the level of position II, then rises convexly across the path of movement of the control elements 1 until position I is reached, and then descends convexly across the path of movement of the control elements 1 until it again reaches position II. The control elements 1 which are polarized in the area of the addressing magnet 5 are therefore first shifted or swung into position I by the sorting pole 37 regardless of their address, and then those control elements 1 are withdrawn from position I back to position II which are polarized oppositely in comparison to the sorting pole 37. The control elements provided with the same polarization as the sorting pole 37 are repelled by the sorting pole as soon as they reach it and are thereby released from the sorting pole 37, so that they not only reach position I but also remain therein.
In the embodiment according to FIG. 5, two patterning system are provided, which are associated with two successive knitting systems of a knitting machine. The patterning system is configured in the left part of FIG. 5 the same as in FIG. 1, while the patterning system represented in the right part of FIG. 5 is the same as the one in FIG. 1 except that it has a sorting magnet 38 which has sorting poles 39 and 40 having polarities opposite those of FIG. 1. By this measure it is possible, in a simple manner, to knit, with the patterning system on the right in FIG. 5, a pattern that is the opposite, or a negative pattern, of that of the left patterning system, without the need for re-addressing, since the control elements 1 with a north-magnetic address, for example, brought into position I, are brought by the right-hand patterning system into position II, and vice versa, if no control signals to change the polarization are fed to the right-hand addressing magnet 5. Such patterning systems are therefore especially suitable for the production of 1:1, 2:2, or other such patterns.
The application of the patterning system according to the invention to a circular knitting machine with a rotating needle cylinder will now be described with the aid of FIGS. 13 to 24.
FIG. 13 shows two identical elevational views of a cylindrical cam 46, as seen in each case from the center of the machine. In the left view, the cam tracks that determine knitting are emphasized, and in the right view the cam tracks that determine missknitting are emphasized. The same applies to the cross sections represented in FIGS. 18 to 24, in which there is also represented a needle cylinder 47 of the circular knitting machine. The direction of rotation of the needle cylinder 47 is indicated by an arrow in FIG. 13. According to FIGS. 13 and 18, needles 48 with butts 49 are mounted for axial displacement in the channels of the needle cylinder 47, and the butts slide in a needle butt track 50 formed by cam sections. Under the needles 48 are jacks 51 having butts 52 which slide in a jack butt track 53 formed by sections of the cam and are mounted in the channels of the needle cylinder 47 both for axial displacement and for swiveling radially. In the backs of the jacks 51 there are mounted resiliently flexible control springs 54 made, for example, of spring steel. The latter have in their upper portions resilient return-spring sections 55 which thrust against the bottom of the channel and against the back of the jack, and serve for the purpose of biasing the jacks 51 resiliently outward. In a middle or lower section the control springs 54 have a slide foot or butt 56 which consists of a U-shaped section bent radially outward, which reaches beneath the lower jack extremities into a control spring foot track 57. At their bottom end the control springs 54 lastly have a selector foot or butt 58, which can consist of an end of the spring adjoining the slide foot 56 and extending radially outward, which is obtained by another U-shaped bend of the control spring 54. The control springs 54 are resiliently deformable parallel to the axis of the needle cylinder in the portions including the slide feet 56 and the selector feet 58, and furthermore they are mounted so as to be axially displaceable in the cylinder channels. To increase the contact area between the control spring and the control element 1, it is advantageous to flatten the round wire cross section in the area of the control element 1 or to bend it sharply at 180°.
Underneath each control spring 54 there is provided a control element according to the invention, which is disposed substantially parallel to the axis of the needle cylinder 47 and is mounted for swiveling radially. According to FIG. 14, the periphery of the needle cylinder 47 is provided with axis-parallel grooves which are defined on both sides by separators or partition walls 60. In the portion of the needle cylinder 47 associated with the needles 48 and jacks 51, barriers or web plates 61 are inserted into the grooves, which form the channels serving to accommodate the needles and jacks. In the section of the needle cylinder 47 underneath the latter the separator walls 60 are provided with portions 62 and 63 which extend radially outwardly, the radially outermost portions 63 having each a recess into which the bottom end of a control element 1 is inserted for swiveling radially. Into the cylinder grooves formed by the portions 62 and 63 there are loosely inserted plates 65 which rest on the bottom of the grooves and are haled in the cylinder grooves by two mounting springs 66 and 67 one over the other, in the form, for example, of helical springs tightly surrounding the needle cylinder. The position of the mounting springs 66 and 67 is secured by corresponding notches in the portions 63 and in the plates 65. The upper mounting spring 67 is disposed at such an axial level that hooks 68 obtained by bending the bottom ends of the control elements 1 come under them, so that the control elements 1 are thus secured in the position seen in FIG. 14. This arrangement has the advantage that the control elements 1 can be inserted individually into the channels formed by the plates 65, after the removal of the cam jacket 46, and can easily be replaced if necessary. The plates 65 consist preferably of a nonmagnetic material, such as spring bronze or plastic.
In FIG. 14 there can furthermore be seen a biasing magnet 71 acting on the upper ends of the control elements 1; it consists of a U-shaped magnet of the kind indicated in FIGS. 9 and 10 and has a permanent magnet 72 and two pole shoes 73 and 74 which are disposed at the level of the address sections 3 and 9, not shown, of the control elements 1, and form with their free ends the biasing poles. On each side of the control elements 1 there is furthermore a wear-resistant guide 75 and 76 consisting preferably of nonmagnetic material, between which the upper ends of the control elements 1 slide, in order to protect the biasing poles against wear. The biasing magnet 71 and the radially outer guide 76 are suspended from a mounting plate 77 fastened to the cam, while the radially inner guide 75 is mounted on a cover 78 removably fastened on the mounting plate 77. The entry ends of the guides 75 and 76 can be curved to match the cams 31 and 32 (FIG. 2).
In FIG. 15, the upper end of the control elements 1, after leaving the biasing magnet 71, is guided on between the guides 75 and 76 and moves past an addressing magnet 79 that follows in the direction of rotation of the needle cylinder 47, and which has a U-shaped core 81 whose free ends form the addressing poles associated with the address sections 3 and 9, which are not shown. The addressing magnet 79 is suspended from the mounting plate 77.
FIGS. 16 and 17 show the sorting process. At a point situated behind the addressing magnet 79 in the direction of rotation of the needle cylinder 47, there is provided a sorting magnet 82 (FIG. 13) acting on the upper address sections 3, which are not shown. The sorting magnet 82 has on the one side of the path of movement of the control elements 1 sorting pole 83, e.g., a north pole, and on the other side of the path of movement an additional sorting pole 84 of the opposite type, e.g., a south pole. The radially inner sorting pole 83 is fastened to the cover 78, and the radially outer sorting pole 84 is fastened to the mounting plate 77. FIG. 16 shows the position of a control element 1 at about the point where the sorting poles 83 and 84 are closest together, while FIG. 17 shows a control element 1 of this kind in the area of the exit funnel of the sorting magnet 82, which can be swung either radially outward (missknit) or radially inward (knit), depending on its addressing. In the knit position the control element 1 lies against the portion 62. Aside from this, the described embodiment has the advantage that the plate 65 can reach in the axial direction right up to the mounting plate 77 or the magnets borne by the latter, so that the control elements are securely guided also in the lateral direction. Otherwise, the sorting described in conjunction with FIG. 2 is substantially the one performed in this embodiment. The magnets or their poles that are represented can be disposed at an angle as a whole, or they can be beveled in order thereby to equalize the different angular attitudes of the control elements.
The manner of operation of the patterning system represented in FIGS. 13 to 24 is as follows: When the needle cylinder 47 revolves in the direction of the arrow, the needles, jacks and control springs represented by their butts run from right to left into the cam segment of FIG. 13 which comprises a complete knitting system. At the point marked by the line A--A, the butts 52 of all jacks are in their normal through-running position, while butts 49 of the needles, depending on whether they have knitted or not in the previous system, may be in a partially extended position and therefore are gradually being pulled down into the through-running position until they reach the line D--D or they are already assuming the through-running position at line A--A. The slide feet 56 of the control springs 54 are located also in a through-running position at line A--A and are held in this position therein by a horizontal guide plate 91 reaching underneath them (FIG. 18). The upper ends of the slide feet 56 are disposed closely beneath the bottoms of the jacks. At the points indicatd by the lines A--A, B--B, C--C and D--D, the biasing, addressing and sorting of the control elements 1 described in conjunction with FIGS. 14 to 17 are performed, which are substantially completed in FIG. 19 corresponding to line D--D. The left view of FIG. 19 shows the radially inwardly swung control elements 1 for the knitting needles, and the lower half the radially outwardly swung control elements 1 for the miss-knitting needles. The knitting needles in the preceding system pulled all the way down into the through-running position in the upper hald of FIG. 19.
In the area of the line E--E (FIG. 20) the slide feet 56 of the control springs 54 encounter a descending section 92 of the guide plate 91, while at the same time the butts 52 of the jacks 51 encounter a descending portion 93 and are lowered by the latter. The needles 48 remain in the through-running position.
The pulling down of the jacks 51 has the result that their bottom ends are pressed against the upper edges of the slide feet 56 of the control springs 54 and push them too axially downward, as indicated in FIGS. 13 and 20. If the control springs 54 are associated with a control element 1 which has been selected to knit and therefore swung radially inward (FIG. 20, left), on account of this downward movement of the jacks 51, the selector foot 58 of the control springs 54 strikes against the upper end of the corresponding control element 1 and is thereby prevented from any further downward movement. If, on the other hand, a control spring 54 is associated with a control element 1 that has been selected to missknit (FIG. 20, right), then the latter is swung radially outward such that the selector foot 58 can be moved downwardly together with the control spring 54 without interference.
FIGS. 13 and 21 show, in the area of the line F--F, the lowest position which the control spring 54 can reach at the end of the descending portion 93. If it is associated with a needle 48 that has been selected to knit (FIG. 21, left), then, in the area which inlcudes the slide foot 56 and the selector foot 58, which is still lying on the corresponding control element 1, the control spring will be resiliently compressed or flexed resiliently in the axial direction, while in the case of selection to missknit (FIG. 21, right it remains virtually in its normal shape and thus its selector foot 58 will lie on the bottom edge of the corresponding channel. The corresponding needles 48 are still in the through position.
The descending portion 93 is contiguous with an ascending portion 94 of the cam. Thus a gap 95 (FIGS. 13 and 22) is formed above the butts 52 of the jacks 51, and as a result those jacks 51 which, as shown in the left view of FIG. 21, are in contact with a resiliently compressed or flexed control spring 54, which is still supported on the corresponding control element 1, will be raised by the resilience of the control spring 54 until the control spring 54 is relaxes, in accordance with the left view of FIG. 13. The control springs 54 which are not supported on a control element 1, however, will remain in the position shown in the right view of FIG. 13 while they are within the gap 95.
Into the bottom portion of the gap 95 extends a section 96 of a cam portion 97 which, as seen from the cam 46, rises radially toward the center of the cam cylinder and is so disposed that it can act only on the butts 52 of the jacks 51 that are selected to missknit. These jacks 51 are therefore gradually swung radially inwardly into the corresponding channel under the bias of the return sections 55 of the control springs 54, until, at the end of the ascending section 96, which is indicated by the line G--G, they are swung completely out of the jack butt track 53 (FIG. 22, right). The butts 52 of the jacks 51 selected to knit are, however, disposed above the radial range of action of section 96, as shown in the left view of FIG. 22, and therefore they are not swung radially by this section 96 but guided on the upper edge thereof.
As it can be seen in FIG. 13, the section 96 of the cam portion 97 is adjoined by a section 98 which, on the one hand, holds the missknitting jacks in the radially swung position (FIG. 13, left view), but on the other hand gradually raises the knitting jacks 51 (FIG. 13, left view). This section 98 is followed, in the direction of rotation of the needle cylinder, by a section 99 of the cam portion 97 which slopes upwardly. The bottom edge of this section 99 releases, as seen in right view of FIGS. 13 and 23, the butts 52 of the jacks 51, which were held in the swung state, in the area of the line H--H, so that these jacks are swung by the effect of the return section 55 of the control springs 54 radially back outward into the jack butt track 53. The ascending upper edge of section 99, however, engages the bottom of the feet 52 of the jacks 51 selected to knit and gradually lifts them further up (FIGS. 13 and 23, left) until their upper edges contact the bottom edges of the needles 48 that are above them, and thus lift them, too (cf. line I--I in the FIGS. 13 and 24, left). The butts 52 of the jacks 51 that have been selected to missknit arrive, at line I--I, in the range of an ejector portion 100 by means of which these jacks return to their normal through-running position. At the same time the slide feet 56 of the control springs 54 encounter an ascending section 101 of the guide plate 91 which raises all the control springs 54 to the normal through-running position. As the movement continues, the jacks 51 selected to knit are lifted by cam portion 97 until the butts 49 of the corresponding needles 48 come into the range of an ejector portion 102 and are ejected by the latter into the knit position, while simultaneously the jacks 51 are pulled down by a pull-down portion 102 to the normal through-running position and, at the end of the cam portion 97, run together with the jacks selected to missknit. The kind of patterning that has been described can then be continued in a subsequent knitting system.
The invention is not limited to the embodiments described, which can be modified in many ways. Instead of the represented control elements 1, control elements of other forms can be used, especially those which contain, in addition to magnetizable sections, other sections made also of nonmagnetizable materials. All that is important is that the area between the two address sections consist of a magnetizable material having a sufficient remanence and coercivity. Furthermore, the control elements can be mounted for sliding instead of swinging. It is furthermore possible to swing the control elements against a light spring force, although this is not necessary if the principle of the invention is applied. The above-described biasing and sorting magnets can consist not only of permanent magnets but also of continuously energized electromagnets. Also, it is possible, in conjunction for example with a flat knitting machine or a circular knitting machine with a revolving cam, to move the above-described biasing, addressing and sorting magnets relative to the control elements. It is also possible to address the control elements only in a middle portion instead of at their one end.
On account of the low magnetic field strengths required, it is furthermore possible to embed in plastic the patterning system block containing the biasing, addressing and sorting magnets. Thus friction surfaces of plastic are produced, on which the control elements can slide without wearing down the magnet pole faces. The air gaps which this creates between the control elements and the magnet poles are acceptable, also in consideration of the low attraction and repulsion forces that need to be applied in range of the sorting magnets. Instead of a selection between knit and missknit, a selection between missknit and tuck or tuck and knit can be provided.
Lastly, a preferred modification of the embodiment according to FIGS. 14 to 17 might consist in lengthening the plates 65 to a point just below the free ends of the control elements 1 and at the same time increase the distance, measured in the direction of the needle cylinder axis, between the pole shoes of the biasing magnet 71 on the one hand and the addressing magnet 79 on the other. This would assure, on the one hand, a guidance of the control elements 1 between the plates 65 also at their upper sections, and, on the other hand, a greater separation of the areas of the control elements 1 that are to be magnetized. So that, in this embodiment too, the bottom pole shoes of the magnets 71 and 79 can reach radially all the way to the control elements, the plates 65 are provided at this point each with a recess accommodating the pole faces. A corresponding recess might also be provided to accommodate the guides 76.
With regard to the embodiment of FIG. 4 it is advantageous to dispose all magnets and cams such that they act on the control elements 1 only from one side, particularly from the outside of the path of movement thereof. In this case contrary to FIGS. 14 to 17 all magnets and cams can be mounted on a common mounting plate, and no means are needed with would have to be disposed behind the control elements 1, e.g. by means of the cover 78. Thus, the assembly of the parts is very much simplified. A particularly preferred embodiment is shown in FIGS. 25 to 28 and described hereinbelow. For thius purpose, identical parts are designated with the same reference numbers according to FIGS. 14 to 17.
Contrary to FIGS. 14 to 17 the plates 56 are provided with extensions 102 at the upper ends thereof, which extensions approximately extend up to the upper edge of the mounting plate 77. In the radial direction the extensions 102 are dimensioned such that they project above the inclined radial portions 62 of the separator walls 60 for a small fraction, i.e. for about a fraction corresponding to the radius of the control elements 1. The portions 62 are inclined such that all control elements 1 which are radially swung inwardly, lie against such portions 62.
The front edge of the mounting plate 1 facing the control elements 1 has--as viewed in the direction of movement of the control elements 1 (see arrow in FIG. 25) - at first a portion 103 inclined from the outside to the inside. Portion 103 is followed by a portion 104 which substantially extends parallel to the periphery of the needle cylinder. Portion 104 is followed by a portion 105 being inclined from the inside to the outside. The distance between the portion 104 and the periphery of the needle cylinder is only slightly greater than the diameter of the control elements 1. The portions 103 to 105 may be made from a material being wear-resistant and preferably unmagnetic. Alternatingly, the control elements could be guided by special guide pieces corresponding to guides 75 and 76.
According to FIGS. 26 to 28 at the underside of the mounting plate 77 the premagnetization magnet 71, the addressing magnet 798 and a sorting magnet 106 are mounted. The sorting magnet 106 comprises to permanent magnets 107 and 108, which e.g. are made from oxide magnets and are interconnected by a soft iron plate in a horseshoe-like manner. By way of example, the pole of the permanent magnet 107 facing the control elements 1 is a north pole, while the pole of the permanent magnet 108 facing the control elements 1 is a south pole. The distance between the poles of the permanent magnets 107 and 108 corresponds to the distance between the pole shoes 74 and 75 or the respective pole shoes of the addressing magnet 79, respectively. The radial innermost poles of the permanent magnet 107 and 108 have a portion 110 being parallel to the periphery of the needle cylinder 47 and to the portion 104 of the mounting plate 77, and a following portion 111 which is inclined to the outside and corresponds to the portions 105 of the mounting plate 77. The front edges of the pole shoes of the premagnetization magnet 71 and of the addressing magnet 79 substantially are flush with the portion 104 of the mounting plate 77.
If the control elements 1 are moved towards the mounting plate 77 in the direction of the arrow (FIG. 25), those control elements 1 which have been radially swung outwardly in a preceding system, at first reach the portion 103 of the mounting plate 77 and thus are gradually swung inwardly up to a position where they lie against the portions 62 of he respective separator walls 60 of the needly cylinder, as shown in FIG. 26. The control elements 1 then arrive at the pole shoes 73 and 74 of the premagnetization magnet 71 and are magnetized accordingly. Thereafter the control elements 1 pass the addressing magnet 79 and are addressed in the desired manner. Finally, the control elements 1 reach the portions 110 and 111 of the sorting magnet 106, by which they are left uninfluenced if the polarity is repelling or gradually drawn out of the grooves of the needle cylinder along portions 105 or 111, respectively, if the polarity is attracting.
A particular advantage of the embodiment of FIG. 25 to 28 is the fact that the backs of the control elements 1 permanently lie against the portions 62 of the partition walls 60 as long as the control elements 1 are swung inwardly, such that the portions 62 which consist of a magnetic conducting material, serve as magnetic shunts between the respective pairs of address sections of the control elements 1. Thus, the control elements 1, independently of their state of magnetization, are retained by magnetic forces from the portions 62 of the separator walls 60 as long as they are not drawn radially outwardly by a ortion 111 of one of the sorting magnets 106. Apart from this, all magnets and guides only act on the control elements 1 from the radial outer side such that it is not necessary to provide the mounting plate 77 or the magnets with means which overlap or extend beyond the control elements 1 and have portions being located in the backs of the control elements 1. Further, according to FIGS. 20 to 24 (upper half) only those control elements 1 are mechanically loaded in an axial direction which elements lie against the portion 62 and are attracted therefrom.
The plates 65 may be made from a magnetic conducting or magnetic non-conducting material in this embodiment.
For optimizing the relation between the adhesion forces and draw-off forces, the magnetic shunt may be changed by partially sparing free the contact profile of the portions 62 within the active region of the control elements 1.
Finally, the section of the needle cylinder 47 shown in FIG. 25 is only shown in a flat development and should be considered slightly curved. Also the mounting plate 77 could be curved, if necessary, within the portion 104. Further, the embodiments described may also be used within a flat knitting machine, in which case the needle bed corresponding to the needle cylinder 47 is stationary, whereas the mounting plate is fastened to a movable part, e.g. a slide, as would also be the case if a circular knitting machine having a rotary cam box ring is used. | The invention relates to a magnetic patterning system on a knitting machine, which has knitting tools which are selectable independently of one another. The patterning system comprises ferromagnetic control elements associated with the knitting tools, an electromagnetic control pole which can be excited according to a pattern, and at least one permanent holding pole, the selection of the knitting tools being performed by relative motion between the control elements and the control pole and the holding pole during which motion the control elements adhere or do not adhere to the holding pole depending on the state of excitation of the control pole. To prevent the control elements from having to be already swung or shifted in the area of the control pole, the control pole is designed as a pole for only addressing address sections of the control elements in order to magnetize them, according to the pattern, to remanent north poles or south poles, while the holding pole is designed as a sorting pole in order to attract or repel the address sections according to their remanent magnetization. | 3 |
This is a continuation of application Ser. No. 08/588,558, filed Jan. 18, 1996; abandoned which is a continuation of application Ser. No. 08/425,785, filed Apr. 20, 1995; U.S. Pat. No. 5,546,531 which is a continuation of application Ser. No. 08/275,644, filed Jul. 15, 1994; abandoned which is a continuation of application Ser. No. 07/870,564, filed Apr. 17, 1992, abandoned.
FIELD OF THE INVENTION
This invention relates to video signal processing generally and particularly to systems for providing a digital signal representative of video and graphics information.
BACKGROUND OF THE INVENTION
The goal of attaining an integrated video/graphics system (Integrated Visual Architecture) requires a system architect to balance often conflicting requirements of video subsystems and graphics subsystems. For example, while increasing horizontal and vertical resolution is beneficial to graphics images, in digital video subsystems increasing horizontal and vertical resolution can actually be detrimental to the overall image quality. Likewise, in graphics subsystems, the pixel depth, i.e. the number of simultaneous colors available, is not as important as it is for video systems. While it may be hard to justify the additional system cost of 16 bit, near-true-color pixels for the graphics system, a video system can arguably make use of deeper 24 bit pixels.
The performance budget of a video processor in a digital video subsystem during playback is divided and used to perform two tasks: creating the video image from a compressed data stream and copying/scaling the image to the display buffer. The performance budget of the video subsystem must be balanced between the copy/scale operation and the video decompression operation. Both operations must get performed thirty times a second for smooth, natural motion video. The division of the performance budget is usually done to worse case which results in an allocation of sufficient performance for a full screen motion video copy/scale operation with the remaining performance being dedicated to the video decompression operation. If the number of pixels (and/or bytes) that have to be written in the copy/scale operation are increased, the performance of the video decompression necessarily decreases. In ever increasing resolutions, for a given level of video technology, a point will be reached where the video image starts to degrade because the information content in the decompressed image is too low. Increasing the resolution beyond this point would be analogous to playing back a poor copy of a VHS tape on the most expensive, highest-quality TV available; the TV would reproduce the low-quality images perfectly.
Several formats have been presented for storing pixel data in a video subsystem. One approach is to simply have 24 bits of RGB information per pixel. This approach yields the maximum color space required for video at the expense of three bytes per pixel. Depending on the number of pixels in the video subsystem, the copy/scale operation could be overburdened.
A second approach is a compromise of the 24 bit system and is based on 16 bits of RGB information per pixel. Such systems have less bytes for the copy/scale operation but also have less color depth. Additionally, since the intensity and color information are encoded equally in the R, G and B components of the pixel, the approach does not take advantage of the human eye's sensitivity to intensity and insensitivity to color saturation. Other 16 bit systems have been proposed that encode the pixels in a YUV format such as 6, 5, 5 and 8, 4, 4. Although somewhat better than 16 bit RGB, the 16 bit YUV format does not come close to the performance of 24 bit systems.
The 8 bit CLUT provides a third approach. This method uses 8 bits per pixel as an index into a color map that typically has 24 bits of color space as the entry. This approach has the advantages of low byte count and 24 bit color space. However, since there are only 256 colors available on the screen, image quality suffers. Techniques that use adjacent pixels to "create" other colors have been demonstrated to have excellent image quality, even for still images. However, this dithering technique often requires complicated algorithms and "custom" palette entries in the DAC as well as almost exclusive use of the CLUT. The overhead of running the dithering algorithm must be added to the copy/scale operation.
One approach for storing pixel data in a video subsystem has been to represent the intensity information with more bits than is used to represent the color saturation information. The color information is subsampled in memory and interpolated up to 24 bits per pixel by the display controller as the information is being displayed. This technique has the advantage of full color space while maintaining a low number of bits per pixel. All of the pixel depth/density tradeoffs are made in the color saturation domain where the effects are less noticeable. Several variations of this method exist and have been implemented in a display processor from Intel. In the Intel system, pixel depths typically range from 4.5 to 32 bits per pixel.
Motion video on the Intel system is displayed in a 4:1:1 format called the "9 bit format". The 4:1:1 means there are 4 Y samples horizontally for each UV sample and 4 Y samples vertically for each UV sample. If each sample is 8 bits then a 4×4 block of pixels uses 18 bytes of information or 9 bits per pixel. Although image quality is quite good for motion video the 9 bit format may be deemed unacceptable for display of high-quality stills. In addition, it was found that the 9 bit format does not integrate well with graphics subsystems. Other variations of the YUV subsampled approach include an 8 bit format.
As noted above, the requirements for a graphics system include high horizontal and vertical resolution with shallow pixels. A graphics system in which the display was 1280×1024 with 8 bit clut pixels would likely meet the needs of all but the most demanding applications. In contrast, the requirements for the video system include the ability to generate 24 bit true color pixels with a minimum of bytes in the display buffer. A video system in which the display was 640×512×8 bit (YUV interpolated to 24 bits and upsampled to 1280×1024) would also meet the needs of most applications.
Systems integrating a graphics subsystem display buffer with a video subsystem display buffer generally fall into two categories. The two types of approaches are known as Single Frame Buffer Architectures and Dual Frame Buffer Architectures.
The Single Frame Buffer Architecture (SFBA) is the most straight forward approach and consists of a single graphics controller, a single DAC and a single frame buffer. In its simplest form, the SFBA has each pixel on the display represented by bits in the display buffer that are consistent in their format regardless of the meaning of the pixel on the display. In other words, graphics pixels and video pixels are indistinguishable in the frame buffer RAM. The SFBA graphics/video subsystem, i.e. the SFBA visual system, does not address the requirements of the video subsystem very well. Full screen motion video on the SFBA visual system requires updating every pixel in the display buffer (30 times a second) which is most likely on the order of 1280×1024 by 8 bits. Even without the burden of writing over 30 M Bytes per second to the display buffer, it has been established that 8 bit video by itself does not provide the required video quality. This means the SFBA system can either move up to 16 bits per pixel or implement the 8 bit YUV subsampled technique. Since 16 bits per pixel will yield over 60 M Bytes per second into the frame buffer, it is clearly an unacceptable alternative.
A visual system must be able to mix video and graphics together on a display which requires the display to show on occasion a single video pixel located in between graphics pixels. Because of the need to mix video and graphics there is a hard and fast rule dictating that every pixel in the display buffer be a stand-alone, self-sustaining pixel on the screen. The very nature of the 8 bit YUV subsampled technique makes it necessary to have several 8 bit samples before one video pixel can be generated, making the technique unsuitable for the SFBA visual system.
The second category of architectures integrating video and graphics is the Dual Frame Buffer Architecture (DFBA). The DFBA visual system involves mixing two otherwise free-standing single frame buffer systems at the analog back end with a high-speed analog switch. Since the video and graphics subsystems are both single frame buffer designs each one can make the necessary tradeoffs in spatial resolution and pixel depth with almost complete disregard for the other subsystem. DFBA visual systems also include the feature of being loosely-coupled. Since the only connection of the two systems is in the final output stage, the two subsystems can be on different buses in the system. The fact that the DFBA video subsystem is loosely-coupled to the graphics subsystem is usually the overriding reason such systems, which have significant disadvantages, are typically employed.
DFBA designs typically operate in a mode that has the video subsystem genlocked to the graphics subsystem. Genlocked in this case means having both subsystems start to display their first pixel at the same time. If both subsystems are running at exactly the same horizontal line frequency with the same number of lines, then mixing of the two separate video streams can be done with very predictable results.
Since both pixel streams are running at the same time, the process can be thought of as having video pixels underlaying the graphics pixels. If a determination is made not to show a graphics pixel, then the video information will show through. In DFBA designs, it is not necessary for the two subsystems to have the same number of horizontal pixels. As an example, it is quite possible to have 352 video pixels underneath 1024 graphics pixels. The Intel ActionMedia™ boards are DFBA designs and can display an arbitrary number of video pixels while genlocked to an arbitrary line rate graphics subsystem. The only restrictions are that the frequency required to support the configuration be within the 82750DB's 12 MHz to 45 Mhz range.
The decision whether to show the video information or the graphics information in DFBA visual systems is typically made on a pixel by pixel basis in the graphics subsystem. A technique often used is called "chroma keying". Chroma keying involves detecting a specific color (or color entry in the CLUT) in the graphics digital pixel stream. Another approach referred to as "black detect", uses the graphics analog pixel stream to detect black, since black is the easiest graphics level to detect. In either case, keying information is used to control the high-speed analog switch and the task of integrating video and graphics on the display is reduced to painting the keying color in the graphics display where video pixels are desired. Intel's ActionMedia II™ product implements chroma keying and black detect.
There are several disadvantages to DFBA visual systems. The goal of high-integration is often thwarted by the need to have two separate, free-standing subsystems. The cost of having duplicate DACs, display buffers, and CRT controllers is undesirable. The difficulty of genlocking and the cost of the high-speed analog switch are two more disadvantages. In addition, placing the analog switch in the graphics path will have detrimental effects on the quality of the graphics display. This becomes an ever increasing problem as the spatial resolution and/or line rate of the graphics subsystem grows.
It is an object of the present invention to provide an integrated system for storing and displaying graphics and video information.
It is further object of the present invention to provide a system for storing and displaying either graphics or video information, which system can be easily upgraded into an integrated system for storing and displaying graphics and video information by merely augmenting the system with additional memory.
Further objects and advantages of the invention will become apparent from the description of the invention which follows.
SUMMARY OF THE INVENTION
The present invention comprises a method and apparatus for processing visual data. According to a preferred embodiment, first memory locations store visual data in a first color format and second memory locations store visual data in a second color format which is different from the first color format. A merged pixel stream is formed from the visual data in the first color format stored in the first memory locations and the visual data in the second color format stored in the second memory locations, and an analog signal is generated representative of the merged pixel stream.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating the operation of a first preferred embodiment of the present invention.
FIG. 2 is a block diagram illustrating the operation of a second preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, there is shown a block diagram illustrating the operation of an apparatus, designated generally 100, for processing visual data according to a first preferred embodiment of the present invention. The invention shown includes first storage means 110 for storing a first bit plane of visual data in a first format. First storage means 110 is coupled to graphics controller 140 through storage bus 132. First storage means 110 and graphics controller 140 are also coupled by data bus 130. The invention also includes means 120 for receiving a second storage means for storing a second bit plane of visual data in a second format different from the first format. Means 120 is adapted to couple a second storage means to graphics controller 140 through the storage bus 132. Means 120 is also adapted to couple the second storage means to graphics controller 140 by data bus 130a. Graphics controller 140 includes means for forming a merged pixel stream from visual data stored on said first and second storage means. Means 160 for displaying the merged pixel stream is also provided. Means 160 is coupled to graphics controller 140 by pixel bus 150. In the preferred embodiment, data bus 130 and data bus 130a are separate 8 bit buses. In an alternative embodiment, a single 16 bit data bus may be used to couple both first storage means 110 and a second storage means to graphics controller 140. Data buses of other widths may also be used.
FIG. 1 shows a base configuration of the present invention in which first storage means 110 is represented by RAM BANK 0. This base configuration may operate in an 8-bit CLUT mode. This mode allows operation of RAM BANK 0 as a Single Frame Buffer Architecture, similar to a VGA or XGA system in 8 bits per pixel mode. The 8-bit CLUT mode allows for operation of the base configuration as a video only or graphics only subsystem. The base configuration may also operate as a SFBA system with limited graphics/video integration (8 bits/pixel) as described in the Background section above. In the 8-bit CLUT mode, the bandwidth of data bus 130 is the same as would be required for a stand alone 8 bit CLUT graphics subsystem.
Means 120 for receiving a second storage means allows the base configuration of the present invention to be easily upgraded by the mere addition of a second storage means to operate either as (i) an integrated system for storing and displaying both graphics and video information ("the Dual Color Space Mode"), or as (ii) an expanded single frame buffer for storing and displaying either graphics only or video only information at a deepened pixel depth and/or increased resolution level ("the Expanded Single Frame Buffer Mode"). In the Dual Color Space Mode, a first type of visual data may be stored in first storage means 110 in a first format, and a second type of visual data may be stored in a second storage means in a second format which is different from the first format. For example, graphics data may be stored in first storage means 110 in RGB format, and video data may be stored in the second storage means in YUV format. In the Expanded Single Frame Buffer Mode, first storage means 110 and a second storage means preferably provide for operation of the system as a video only system or a graphics only subsystem with 16 bits per pixel. The Expanded Single Frame Buffer Mode may also operate as a SFBA system with limited graphics/video integration (16 bits/pixel) as described in the Background section above.
Graphics controller 140 includes means for forming a merged pixel stream from data in a first format stored on storage means 110 and data which may be stored in a second format on a second storage means, once a second storage means is received by means 120. According to a preferred embodiment, when the base system is upgraded (e.g., when a second storage means is received by means 120) and operating in the Dual Color Space Mode, graphics data is stored in one of the storage means in 8-bit CLUT format, and video data is stored in the other storage means as 8 bit YUV data. The preferred format of the 8 bit YUV data in the Dual Color Space Made is shown in Table I below, with each position being a single byte:
TABLE I
Y.sub.a U.sub.a Y.sub.b V.sub.a Y.sub.c U.sub.b Y.sub.d V.sub.b Y.sub.e U.sub.c . . .
In the Dual Color Space Mode, a first pixel stream representing the RGB graphics pixels (GP n ) is processed in parallel with a second pixel stream representing YUV video pixels. The two parallel pixel streams are stored in parallel in accordance with the format shown in Table II below:
TABLE II______________________________________GP.sub.1GP.sub.2 GP.sub.3 GP.sub.4 GP.sub.5 GP.sub.6 GP.sub.7 GP.sub.8 GP.sub.9 . . . .Y.sub.aU.sub.a Y.sub.b V.sub.a Y.sub.c U.sub.b Y.sub.d V.sub.b Y.sub.e . . .______________________________________ .
The pixels generated by the video subsystem (VP n ) in the Dual Color Space Mode are preferably 24 bit RGB values derived from 24 bit YUV pixels. The 24 bit YUV pixels are determined for each video pixel VP n , in accordance with the formula shown in Table III below:
TABLE III
Y=Y.sub.a, U=U.sub.a, and V=V.sub.a for VP.sub.1 ;
Y=0.5Y.sub.a +0.5Y.sub.b, U=0.75U.sub.a +0.25U.sub.b, and V=0.75V.sub.a +0.25V.sub.b for VP.sub.2 ;
Y=Y.sub.b, U=0.5U.sub.a +0.5U.sub.b, and V=0.5V.sub.a +0.5V.sub.b for VP.sub.3 ;
Y=0.5Y.sub.b +0.5Y.sub.c, U=0.25U.sub.a +0.75U.sub.b, and V=0.25V.sub.a +0.75V.sub.b for VP.sub.4 ;
Y=Y.sub.c, U=U.sub.b, and V=V.sub.b for VP.sub.5, and so on.
Other subsampling techniques may be used to build the RGB values.
In the preferred embodiment, chroma keying is preferably used on the graphics pixel stream to determine whether to show a graphics pixel or a video pixel. In the example of Table II, if GP 3 and GP 4 , held pixel values equal to the chroma key value, then the merged graphics and video pixel stream (the visual pixel stream) provided to the DAC would have the format shown in Table IV below:
TABLE IV
GP.sub.1 GP.sub.2 VP.sub.3 VP.sub.4 GP.sub.5 GP.sub.6 GP.sub.7 GP.sub.8 GP.sub.9 . . .
Referring now to FIG. 2, there is shown a block diagram-illustrating the operation of an apparatus, designated generally 200, for processing visual data according to a second preferred embodiment of the present invention. The invention shown includes first storage means 210 for storing a first bit plane of visual data in a first format. First storage means 210 is coupled to graphics controller 240 through storage bus 232. First storage means 210 and graphics controller 240 are also coupled by data bus 230. The invention also includes second storage means 220 for storing a second bit plane of visual data in a second format different from the first format. Second storage means 220 is coupled to graphics controller 240 through storage bus 232. Second storage means 220 and graphics controller 240 are also coupled by data bus 230a.
Graphics controller 240 includes means for forming a merged pixel stream from visual data stored on said first and second storage means. Means 260 for displaying the merged pixel stream is also provided. Means 260 is coupled to graphics controller 240 by pixel bus 250. In the preferred embodiment, data bus 230 and data bus 230a are separate eight bit buses. In an alternative embodiment, a single 16 bit data bus may be used to couple both first storage means 210 and second storage means 220 to graphics controller 240. Data buses of other widths may also be used. Apparatus 200 functions substantially in accordance with apparatus 100, with a second storage means having been received by means 120. Apparatus 200 is thus configured to operate either in the Dual Color Space or the Expanded Single Frame Buffer Modes described above.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes of the invention. Accordingly, reference should be made to the appended claims, rather than the foregoing specification, as indicating the scope of the invention. | Visual data in a first color format stored in first memory locations are merged with visual data in a second color format, which different from the first color format, stored in second memory locations to form a merged pixel stream. An analog signal is generated representative of the merged pixel stream. In a preferred embodiment, one set of visual data is graphics data in an 8-bit CLUT format and the other set is video data in an 8-bit packed YUV9 format (also known as the 4:1:1 format). In this embodiment, the video data is unpacked and chromakeying is applied to generate the merged pixel stream. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] Pursuant to 35 U.S.C. § 119(e), this application claims the benefit of prior U.S. provisional application No. 60/293,888, filed May 24, 2001.
BACKGROUND
[0002] Many analytical and preparative methods in biology and chemistry require the attachment of target compounds, such as peptide ligands or oligonucleotide probes, to a solid support. Frequently, different species of target compounds are attached onto the surface of the solid support, each at a discrete location. Attachment can be achieved in a number of different ways, including covalent and non-covalent interaction. Typically, covalent attachment is more robust. See, for example, Lamture et al. (1994) Oligonucleotide Research 22: 2121-2125; Beattie et al. (1995) Mol. Biotechnol. 4: 213-225; Joos et al. (1997) Anal. Biochem 247: 96-101; Rogers et al. (1999) Anal. Biochem. 266: 23-30; and Chrisey et al. (1996) Oligonucleotide Research 24: 3031-3039.
[0003] Protocols have been developed to covalently attach a target compound to a support surface. One exemplary protocol includes synthesizing an oligonucleotide directly on a support surface using stepwise photolithographic reactions. Another exemplary protocol includes depositing a target nucleic acid, such as a cloned cDNA, a PCR product, or a synthetic oligonucleotide onto a surface of a solid support, e.g., a microscopic glass slide, in the form of an array. The surface can be modified in order to facilitate the attachment of the nucleic acid. The array is used in hybridization assays to determine the presence or abundance of particular sequences in a sample.
SUMMARY
[0004] The invention is based, in part, on the discovery of a new method of modifing the surface of a solid substrate. The modified surface is useful, for example, for the covalent attachment of target compounds, such as oligonucleotides.
[0005] One aspect of this invention relates to a solid substrate that includes a chemical group covalently bonded to its surface. The chemical group is of formula (I) shown below:
[0006] In the formula, SS is the surface; n is 0-8; X is a bond, O, S, or NH; Y is H, alkyl, arylalkyl, or heteroarylalkyl, wherein the alkyl, aralkyl, or heteroarylalkyl is optionally substituted with an electron-withdrawing group; Z is hydrogen, hydroxy, alkyl, alkenyl, alkynyl, aryl, or heteroaryl, wherein the alkyl, alkenyl, alkynel, aryl, or heteroaryl is optionally substituted with alkyl, halo, hydroxy, amino, carboxy, or oxo; each of A 1 and A 2 , independently, is O, S, or NH; L is alkylene, alkenylene, or alkynylene, and is optionally substituted with halo, hydroxy, nitro, amino, carboxyl, or oxo, or is optionally inserted with —O—, —CO—O—, —CO—NH—, —CO—N(alkyl)—, —NH—CO—, or —N(alkyl)—CO—; and M is a bond or alkylene, alkenylene, or alkynylene, wherein the alkylene, alkenylene, or alkynylene is optionally substituted with halo, hydroxy, nitro, amino, carboxyl, or oxo, or is optionally inserted with —O—, —CO—O—, —CO—NH—, —CO—N(alkyl)—, —NH—CO—, or —N(alkyl)—CO—.
[0007] Embodiments of the above-described solid substrate include those in which n is 0-4; those in which X is NH; those in which Y is H or alkyl optionally substituted with an electron-withdrawing group; those in which Z is alkyl, aryl, or heteroaryl, optionally substituted with alkyl, halo, hydroxy, amino, carboxy, or oxo; those in which each of A 1 and A 2 , independently, is O; those in which L is alkylene (e.g., ethylene); and those in which M is a bond.
[0008] The term “alkyl,” alone or in combination (e.g., as in heteroarylalkyl), refers to a C 1-10 straight or branched hydrocarbon chain, containing the indicated number of carbon atoms. The terms “alkenyl” and “alkynyl” respectively refer to a C 1-10 straight or branched hydrocarbon chain containing at least one double bond and a C 1-10 straight or branched hydrocarbon chain containing at least one triple bond. The term “alkylene” refers to a divalent alkyl group (i.e., —R—). Likewise, the term “alkenylene” and “alkynylene” respectively refer to a divalent C 1-10 alkenyl group and a divalent C 1-10 alkynyl group, respectively. The term “aryl” refers to a 6-carbon monocyclic or 10-carbon bicyclic aromatic ring system in which each ring may be mono-, di-, or multi-substituted. Examples of aryl groups include phenyl and naphthyl. The term “arylalkyl” refers to alkyl substituted with an aryl. The term “heteroaryl” refers to an aromatic 5-8 membered monocyclic, 8-12 membered bicyclic, or 11-14 membered tricyclic ring system having 1-3 heteroatoms if monocyclic, 1-6 heteroatoms if bicyclic, or 1-9 heteroatoms if tricyclic, the heteroatoms being O, N, or S. Each ring of the heteroaryl may be mono-, di-, or multi-substituted. Examples of heteroaryl groups include pyridyl, furyl or furanyl, imidazolyl, benzimidazolyl, pyrimidinyl, thiophenyl or thienyl, quinolinyl, indolyl, and thiazolyl. The term “electron-withdrawing group” refers to a functional group that draws electrons to itself more than a hydrogen atom would if it occupied the same position as the electron-withdrawing group in a molecule. Examples of electron-withdrawing groups include a positively charged group, halogen, cyano, nitro, carbonyl, carbamido, carbamyl, carboxyl, thioureido, thiocyanato, and sulfoamido. By “substituting” or “substitution,” it is meant that at least one or more substituents (which can be the same or different) can be attached to any moiety of the base group. For example, in “arylalkyl substituted with halo,” the halo substituent can be on either aryl or alkyl.
[0009] The term “solid substrate,” as used herein, includes both flexible and rigid substrates. By “flexible” is meant that the solid substrate is pliable. For example, a flexible substrate can be bent, folded, or similarly manipulated to at least some extent without breakage. The surface of a solid substrate may include a planar surface (e.g., a slide or a plate), convex surface (e.g., a bead), concave surface (e.g., a well), and so forth. Potentially useful solid substrates include: mass spectroscopy plates (e.g., for MALDI), glass (e.g., functionalized glass, a glass slide, porous silicate glass, a single crystal silicon, quartz, UV-transparent quartz glass), plastics and polymers (e.g., polystyrene, polypropylene, polyvinylidene difluoride, poly-tetrafluoroethylene, polycarbonate, PDMS, acrylic), metal coated substrates (e.g., gold), silicon substrates, latex, membranes (e.g., nitrocellulose, or nylon), and a refractive surface suitable for surface plasmon resonance. Solid substrates can also be porous. Useful porous substrates include: agarose gels, acrylamide gels, sintered glass, dextran, meshed polymers (e.g., macroporous crosslinked dextran, sephacryl, and sepharose), and so forth.
[0010] Other embodiments of the solid substrate include those in which n is 1; those in which Y is nitromethyl or cyanomethyl; those in which Z is (4-methyl)phenyl; those in which L is ethylene.
[0011] Another aspect of this invention relates to a method for preparing a solid substrate having a modified surface. The method includes providing a solid substrate that contains a SS—M—X—H group and reacting the solid substrate with a coupling compound of the following formula
[0012] in which P is —OH, —NH 2 , or —SH, to convert the surface to a chemical group of formula (I) shown above.
[0013] The invention also relates to a method for covalently attaching a target compound having a nucleophilic group. The method includes providing a solid substrate having a surface covalently bonded to a group of formula (I) shown above, and contacting a target compound to the surface, whereby the nucleophilic group reacts with the activated group to covalently bond the target compound to the surface. The target compound can be uniformly or differentially disposed on the surface, with a density of the compound on the surface of 0.1 to 10 pmol/cm 2 . Examples of the target compound include polymeric compounds, such as an oligonucleotide, a peptide, a polypeptide, a polysaccharide, or a combination thereof; monomeric compounds, such as a nucleoside, an amino acid, or a monosaccharide; and other organic compounds, e.g., a non-polymeric compound have a molecular weight of at least 50, 100, 500, 1000, 5000, 10,000, or greater. The target compounds include analogs of naturally occurring compounds.
[0014] A “nucleophilic group” refers to a chemical moiety that is rich in electron and tends to react with electron-deficient moiety within a compound. Examples of a nucleophilic group include anions (e.g., HO − ), alkoxy (e.g., —OCH 3 ), arylthio (e.g., —SC 6 H 5 ), amino (e.g., —NH 2 ), and aryl (e.g., pyridinyl).
[0015] Also within the scope of this invention is a solid substrate which includes a modified surface with a plurality of addresses, wherein each address has attached thereto a compound of formula (I) shown above.
[0016] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety. In case of conflict, the present specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.
[0017] The details of one or more embodiments of the invention are set forth in the description below. Other features, objects, and advantages of the invention will be apparent from the description and from the claims.
DETAILED DESCRIPTION
[0018] This invention relates to a solid substrate having a surface characterized by a covalently bonded activated group that includes an electron-withdrawing group on an N-substituted sulfonamide. The activated group can be used to attach a target compound, e.g., a target compound having an amino leaving group, to the surface.
[0019] The solid substrate can be prepared by a method known in the art. For instance, one can first provide a substrate having a reacting group SS—M—X—H (each of SS, M, and X is defined as above); attaching a molecule to the substrate to form a covalent bond between the reacting group and the molecule, thereby obtaining a substrate having a modified surface having a chemical group of formula (I).
[0020] Shown below is a scheme that depicts synthesis of a molecule (top) and modification of a surface to provide a highly activated substrate (bottom):
[0021] In this method, a sulfonamide is first coupled with an anhydride in the presence of a base, e.g., diisopropylethylamine, to produce a carbamide molecule that can be used to modify a surface of a solid substrate. The carbamide molecule is then coupled with an amino group on the surface to covalently bond the molecule to the surface. The modified surface is reacted with an iodoacetonitrile to produce a N-cyanomethyl-sulfonamide. Other compounds (e.g., those in which A 1 and A 2 are not both O, or n is not 1 or Z is alkyl) can be prepared by similar methods.
[0022] As shown below, the sulfoamide can undergo a reaction with a target molecule (e.g., a polynucleotide) so that the target molecule can be covalently bonded to the surface of a solid substrate.
[0023] This reaction can occur in only a few minutes at ambient temperature and may be carried out in a variety of mediums such as water, an aqueous buffer, and an organic solvent.
[0024] The solid substrate can be a solid or porous solid support. In some implementations, the support is a bead, microparticle, a nanoparticle, a matrix, or a gel. Beads, microparticles, and nanoparticles can be used, e.g., in chemical and library screening applications. Beads, matrices, gels and other solid supports can be used, e.g., in ligand purification methods, e.g., as a matrix for column chromatography. The beads can include interior surfaces that increase effective surface area and also partition components. Some particles include a radiofrequency tag that can uniquely identify the particle (e.g., as described in U.S. Pat. No. 5,262,530).
[0025] The substrate used herein can be made from any material either flexible or rigid. In general, the substrate material is resistant to the variety of synthesis and analysis conditions of the combinatorial chemical assays. Examples of substrate materials include, but are not limited to, glass, quartz, silicon, gallium aresenide, polyurethanes, polyimides, and polycarbonates. Of course, the substrate material can be a composite of one or more materials. For example, glass supports, i.e., glass slides, can be coated with a polymer material to produce a substrate. Additionally, the support can be made in any shape, e.g., flat, tubular, round, and include etches, ridges or grids to create a patterned substrate. The substrate can be opaque, translucent, or transparent. The substrate can include wells or moats.
[0026] This invention also relates to a method for covalently attaching a target compound to a solid support. The target compound can be a polymeric compound or a monomeric compound. It can be prepared using any known methodology. The particular method for preparing a target compound, such as a modified target compound, to include the requisite reactive group will depend on the nature of the target compound and the nature of the reactive group, which is to be incorporated into the compound. For example, where the target compound is an oligonucleotide, a number of protocols exist for producing an oligonucleotide with or without a reactive group. For instance, an unmodified oligonucleotide can be synthesized on a DNA/RNA synthesizer using a standard phosphoramidite chemistry. A reactive group can be present on a modified phosphoramidite, which can be incorporated into any position of the oligonucleotide during synthesis. Alternatively, a reactive group can be enzymatically added to one of the termini of an oligonucleotide. In another example, where the target compound is a peptide, it can be prepared chemically (e.g., on a peptide synthesizer) or biologically (e.g., expressed from a host cell or in vitro translated). The moiety in peptide, such as carboxy, hydroxy, phenoxy, amino, guanidino, or thio, can serve as a reactive group. An additional reactive group can be introduced into a modified peptide by, for example, incorporation of a modified amino acid.
[0027] An example of the target compound is an oligonucleotide, which can be covalently attached to the solid substrate of this invention at either the 3′ or the 5′ terminus, or alternatively, at a specific position along the sequence. The oligonucleotide can be a synthetic DNA, a synthetic RNA, a cDNA, a mRNA, or a PNA, which is generally at least about 5, 10, or 15 nucleotides in length, and may be as long as 2000, 3000, or 5000 nucleotides or longer.
[0028] The oligonucleotide molecules can be attached to the solid substrate randomly, or in an order. Preferably, the oligonucleotide molecules are arranged into an ordered array. As used herein, an ordered array is a regular arrangement of molecules, as in a matrix of rows and columns. The methods of the present invention are such that an individual array can contain a number of unique attached oligonucleotide molecules. The array can contain more than one distinct attached oligonucleotide molecule.
[0029] Also within the scope of this invention is an array fabricated on a solid substrate of this invention. A target compound, such as an oligonucleotide, a peptide, a polysaccharide, a nucleoside, an amino acid, a monosaccharide, or another organic compound, can be deposited on the solid substrate in the form of an array. The array thus described can be used in a variety of applications. For example, the presence of a particular analyte in a given sample is detected qualitatively or quantitatively. More specifically, the sample suspected of containing the analyte of interest is contacted with the array under conditions sufficient for the analyte to interact with its respective pair member that is present on the array. Thus, if the analyte of interest is present in the sample, it can form a complex with its pair member on the array. The presence of the complex on the array can be detected by a detectable label such as an enzymatic, isotopic or fluorescent label. The detectable label can include a signal production system such as a chemiluminescent system or a proximity detection system.
[0030] The afore-mentioned array can have a density of at least 10, 50, 100, 200, 500, 10 3 , 10 4 , 10 5 , 10 6 , 10 7 , 10 8 , or 10 9 addresses per cm 2 , and/or a density of no more than 10, 50, 100, 200, 500, 10 3 , 10 4 , 10 5 , 10 6 , 10 7 , 10 8 , or 10 9 addresses/cm 2 . Preferably, the plurality of addresses includes at least 10, 100, 500, 1,000, 5,000, 10,000, or 50,000 addresses, or less than 9, 99, 499, 999, 4,999, 9,999, or 49,999 addresses. The center to center distance between addresses can be 5 cm, 1 cm, 100 mm, 10 mm, 1 mm, 10 nm, 1 nm, 0.1 nm or less and/or ranges between. The longest diameter of each address can be 5 cm, 1 cm, 100 mm, 10 mm, 1 mm, 10 nm, 1 nm, 0.1 nm or less and/or ranges between. Each address contains 10 mg, 1 mg, 100 ng, 1 ng, 100 pg, 10 pg, 0.1 pg, or less of a target compound and/or ranges between. Alternatively, each address contains 100, 10 3 , 10 4 , 10 5 , 10 6 , 10 7 , 10 8 , or 10 9 , or more molecules of the reactive compound attached thereto and/or ranges between. Addresses in addition to addresses of the plurality can be deposited on the array. The addresses can be distributed, on the substrate in one dimension, e.g., a linear array; in two dimensions, e.g., a planar array; or in three dimensions, e.g., a three dimensional array.
[0031] A substrate with a planar surface having the activated chemistry described herein can be used to generate an array of a diverse set of target compounds. In one exemplary application, oligonucleotide probes of differing sequence are positioned on the array surface. Such an oligonucleotide array can be used to query a complex sample and generate a large data set. This application and similar hybridization based applications can be used for gene discovery, differential gene expression analysis, sequencing, or genomic polymorphism analysis. Further, such oligonucleotide arrays are particularly amenable to high-throughput applications. Other exemplary applications are polypeptide arrays, e.g., arrays of antigens and/or antibodies.
[0032] The specific examples below are to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way whatsoever. Without further elaboration, it is believed that one skilled in the art can, based on the description herein, utilize the present invention to its fullest extent. All publications, including patents, cited herein are hereby incorporated by reference in their entirety.
EXAMPLE 1
[0033] A. Generation of Amino Groups on Glass Slides:
[0034] 25×75 mm glass slides (VWR International, West Chester, Pa., Cat. No. 48300-025) were washed thoroughly with de-ionized water, immersed in 6 N HCl overnight, and then washed with acetone. These glass slides were baked at 105° C. in an oven for 30 minutes. The slides were then coated with 5.6% gamma-amino propyltriethoxysilane (GAPS) in toluene at 80° C. for 16 hours. The coated slides were washed sequentially with toluene, methanol, and methanol/water solution. Un-reacted silanols on the surface were capped with 50% chlorotrimethylsilane solution in pyridine. The slides were washed with methanol and ethyl ether, and then blow-dried with nitrogen. These slides, “amino glass slides,” were modified with 3-carboxypropionyl-p-toluenesulfonamide as described in Example 1, section C, below.
[0035] B. Synthesis of 3-carboxypropionyl-p-toluenesulfonamide:
[0036] The compound 3-carboxypropionyl-p-toluenesulfonamide was synthesized by reacting p-toluenesulfonamide (8.62 g, 50.3 mmol) with succinic anhydride (6.12 g, 24.9 mmol) in the presence of diisopropylethylamine (21.5 mL, 123 mmol) and a catalytic amount of 4-dimethylaminopyridine (0.62 g, 5.1 mmol) in acetonitrile (85 mL) at room temperature overnight. The organic solvent of the reaction mixture was evaporated using a rotary evaporator. 75 mL of 1.0 N sodium hydroxide solution was added to the oily residue with mixing. The resulting solution was washed with 75 mL of methylene chloride. The aqueous solution was then acidified by addition of approximately 110 mL of 1.0 N hydrochloric acid. A white cloudy solution was observed. White crystals were collected and dried using a water aspirator and then under vacuum for overnight. The product was 3-carboxypropionyl-p-toluenesulfonaminde in the form of a white crystalline material (12.3 g, 90% yield). The structure of the product was confirmed by NMR analysis.
[0037] mp: 167-169° C.
[0038] [0038] 1 H NMR (400 MHz, DMSO-d 6 ): δ 5 2.35 (t, 2H), 2.39 (s, 3H), 2.43 (t, 2H), 7.78 (d, 2H), 7.41 (d, 2H), and 12.1 (s, 2H).
[0039] C. Coating of 3-carboxypropionyl-p-toluenesulfonamide to Primary Amino Groups on Glass Slides:
[0040] A solution of 1.08 g of 3-carboxypropionyl-p-toluenesulfonamide (0.2 M) and 2.18 g of benzotriazo-1-yloxytripyrrolidinophosphonium hexafluorophosphate (PyBOP, 0.21 M) in 18.5 mL of N, N-dimethylformamide (DMF) was prepared. This solution was mixed with 1.5 mL of diisopropylethylamine in a slide cartridge. Amino glass slides were immersed into the cartridge. The reaction mixture with the slides was agitated with an orbital shaker on a magnetic stirrer plate overnight. The coated slides were washed with DMF, methylene chloride, and methanol. The washed slides were dried under vacuum.
[0041] D. Activation of the Coated Slides:
[0042] A mixture of 1.5 mL of diisopropylethylamine, 2.2 mL of iodoacetonitrile, and 16 mL of N-methyl-2-pyrrolidinone (NMP) was prepared in a slide cartridge. The coated slides prepared in Example 1, Section C (above), were immersed in the mixture in a dry box. The reaction mixture was agitated using an orbital shaker on a magnetic stirrer plate for ˜24 hr at room temperature. The slides were washed with NMP and methylene chloride and were dried under vacuum. These slides, the “activated slides,” were stored and later used as described in the Examples below.
EXAMPLE 2
[0043] A. Covalent Attachment of an Oligonucleotide at Different Concentrations:
[0044] A 5′-Cy3-labeled and 3′-amino-modified oligonucleotide probe of 21 nucleotides in length (5′-Cy3-GTACTGCACCAGGCGGCCGCA-NH 2 -3′, SEQ ID NO: 1) was spotted onto the activated slides from Example 1 (Section D). The probe was tested at a variety of concentrations, 1.25, 2.5, 5, 10, 20, and 40 μM, in each of three different spotting solutions: 150 mM sodium phosphate, pH 8.5; 50% Micro Spotting Solution (TeleChem, Sunnyvale Calif.; and 3×SSC. The solutions were spotted onto the activated slides using a 0.787 mm solid pin (V&P Scientific) that produces a 35 nL hanging drop. After spotting, the slides were dried overnight at room temperature and then scanned at 30 μm resolution in a ScanArray 4000 (Packard Biochip, Meriden Conn.) with a laser power setting of 70 and PMT gain of 70. Then, the slides were blocked for 2 h at room temperature using NoAb® 1×Pre-Hybridization/Blocking Buffer (NoAb Diagnostics, Ontario Canada) containing primary and secondary amino groups. After blocking, the slides were washed twice with 0.1×SSC/0.1% SDS, rinsed briefly in 0.1×SSC and H 2 O. The slides were scanned again at a laser power setting of 70 and PMT gain of 70.
[0045] Prior to blocking and washing steps, the fluorescence signal intensities for the Cy3-labeled oligonucleotides at spotting concentrations ranging from 1.25 μM to 40 μM were similar for all slides. Signal intensities were reduced after blocking and washing steps. The fluorescence signal intensity of each spot on the various slides was analyzed using QuantArray 2.0 (Packard Biochip, Meriden Conn.) software. The net fluorescence signal intensity was calculated by subtracting the average background signal from the signal measured at each spot. With all three spotting solutions, 150 mM sodium phosphate, pH 8.5, 50% Mirco Spotting solution (TeleChem, Sunnyvale Calif.), and 3×SSC, a concentration-dependent increase in net fluorescence signal intensities was observed.
[0046] Two reference slides that have a different surface chemistry from the activated slides described above were treated in parallel to compare performance. The glass slides treated with aldehyde compounds such as the aldehyde slides (ALS-25) from CEL ASSOCIATES (Houston, Tex.) were used as the reference slides. The spotted probe also bound to the reference slides in a concentration dependent manner regardless of the spotting solution used.
[0047] However, compared to the two reference slides, the slides described herein exhibited stronger fluorescence signal intensities for all three spotting solutions at each of the concentrations tested. Curves were generated for net fluorescence intensity versus concentration of probe in the spotting solution. The slope of the curves was steepest for the activated slides of Example 1 compared to the two reference slides. In addition, the activated slides were efficiently saturated with a solution of spotting oligonucleotide. These unexpected results are indicative of the high performance properties of the reactive group on the slides of Example 1.
[0048] B. Kinetics of Covalent Attachment
[0049] The 5′-Cy3-labeled and 3′-amino-modified oligonucleotide probe just described was prepared at a concentration of 1.25, 2.5, 5, 10, 20, and 40 μM in 150 mM sodium phosphate and spotted in duplicate in reverse chronological order at 18, 4, 2, 1, 0.5, and 0.25 hours onto activated slides from Example 1. At time 0, the slides were scanned at 30 μm resolution in a ScanArray 4000 (Packard Biochip, Meriden Conn.) with a laser setting of 70 and PMT gain of 70. Then, the slides were blocked for 2 hours at room temperature using NoAb® 1×Pre-Hybridization/Blocking Buffer (NoAb Diagnostics, Ontario Canada), washed twice with 0.1×SSC/0.1% SDS, and rinsed briefly in 0.1×SSC and H 2 O. The slides were scanned first with a laser setting of 70 and PMT gain of 70 and then with a laser setting of 70 and PMT gain of 60. Finally, the slides were sonicated for 30 minutes at room temperature in 0.1×SSC/0.1% SDS, rinsed briefly in 0.1×SSC and H 2 O, and scanned again with a laser setting of 70 and PMT gain of 60.
[0050] The kinetics of covalent attachment of the Cy3-labeled, amino-modified oligonucleotides to activated slides of the invention was compared to that of the reference slides. Both types of slides exhibit similar fluorescence intensities before blocking and washing. Scans taken after blocking and washing, at a laser setting of 70 and PMT gains of 70 and 60, shows that the slides exhibit faster kinetics and higher attachment efficiency at all dispensing concentrations. Scans taken after sonication at laser setting of 70 and PMT gain of 60 indicate that the attachment of the spotted oligonucleotides remains permanently bonded on both slides.
[0051] Quantitative measurements of the kinetics of attachment of amine-modified oligonucleotide were obtained for both the activated slides of Example 1 and the reference slides as described above. The commercial slides exhibit a time-dependent increase in net fluorescence signal intensity, reaching a maximum of ˜4500 net fluorescence signal intensity with 40 μM spotted oligonucleotide after 18 hours of coupling. The slides also exhibit a time-dependent increase in net fluorescence signal intensity. The net fluorescence signal intensity generated using a spotting oligonucleotide concentration of 1.25 μM was more than twice of that of the intensity of spots on the references slides that were formed using the highest concentration of spotted oligonucleotide for the longest treatment time. Not only was the kinetics of the attachment of the spotted probe to the activated slides of example 1 much faster than one of the reference slides for 40 μM spotted oligonucleotide, but also the signal at saturation for the activated slide of Example 1 was at least twelve times stronger than that of the reference slide.
EXAMPLE 3
[0052] An oligonucleotide array was fabricated and used for hybridization of Cy3-labeled complementary oligonucleotide samples. An oligonucleotide probe of 21 nucleotides in length (5′-NH 2 -GTACTGCACCAGGCGGCCGCA-3′; SEQ ID NO: 2) was spotted onto the slides from Example 1 as described above. The probe was at a concentration of 25, 50, 100 and 200 μM in four different spotting solutions, namely, 50% DMSO, 50% Micro Spotting Solution, H 2 O; or 3×SSC. After spotting, the slides were dried overnight at room temperature.
[0053] The slides were hybridized with 80 μL of 200 nM synthetic Cy3-labeled oligonucleotide target 5′-Cy3-TGCGGCCGCCTGGTGCAGTAC-3′ (SEQ ID NO: 3) in a Coverwell Perfusion Chamber (Grace Bio-Labs, Bend Oreg.) in a hybridization solution of 100 mM (2-[N-Morpholino]ethenesulphonic acid (MES), 1 M NaCl, 20 mM EDTA, and 0.01% (vol/vol) Tween 20. The hybridization was carried out overnight at room temperature in a humid plastic container. The slides were washed twice for 5 min each with 5×SSPE (0.75M NaCl, 50 mM NaH 2 PO 4 , 5 mM EDTA, pH7.4) and 0.01% (vol/vol) Tween 20, rinsed in H 2 O, and scanned at 30 μm resolution in a ScanArray 4000 (Packard Biochip) with a laser setting of 70 and PMT gain of 70. Comparing to the reference slides, the slides from Example 1 exhibited the saturation of the fluorescence signal intensities at the lowest concentration of amino-modified oligonucleotide in all 4 spotting solutions, which suggested better attachment efficiency in the slides from Example 1.
[0054] The fluorescence signal intensities of the hybridized probe approached saturation more rapidly for the slides of Example 1 than the reference slides, regardless of the spotting solution used. This finding suggests that the attachment efficiency of the spotted oligonucleotide on the slides of Example 1 exceeds that of the reference slides, as measured by amount of hybridizable probe.
OTHER EMBODIMENTS
[0055] From the above description, one skilled in the art can easily ascertain the essential characteristics of the present invention, and without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions. Accordingly, other embodiments are also within the scope of the following claims. | This invention relates to a solid substrate that has a modified surface to which a sulfoamido group is attached via a linker. | 2 |
FIELD OF THE INVENTION
[0001] This invention relates generally to detecting and/or measuring DNA markers related to cell damage, e.g., as a consequence of pathophysiological or traumatic insults, especially in a nuclear accident, bioterror attack, tumorigenesis, infections or in individuals with cardiovascular disease(s). In particular, this invention relates to using one or more generic biomarkers to detect and/or measure cell damages in a subject.
BACKGROUND OF THE INVENTION
[0002] Genomic DNA in healthy cells is normally confined within the nucleus of the cells. However, genomic DNA is released into the circulation during cell aging where cells undergo programmed cell death or apoptosis, or during early disease states. These circulating DNAs are often not detectable in healthy individuals because of the homeostatic ability to efficiently eliminate them from the circulation. Likewise, circulating DNA in individuals during early disease stage, such as during early tumorigenesis, do not express tumor specific markers in amounts high enough for early detection using currently available nucleic acid detection methods. Although circulating DNA from individuals in the early stage of tumor development may be higher than normal healthy individuals, there are currently no biomarkers that would discriminate between circulating DNA released as a result of tumorigenesis and normal cell aging in individuals. In addition, most if not all of the free circulating DNA is eliminated from the circulation using the same cell machinery as in healthy individuals.
[0003] Furthermore, in circumstances where individuals have been exposed to high levels of radiation, for example in a nuclear accident, or high levels of radiation and/or infectious agent in a bioterror attack, massive cell damage ensues resulting in high levels of genomic DNA being released into circulation. However, there is not currently available a method for an efficient, reliable and inexpensive means for detecting these individuals for the purpose of treating and quarantining these individuals from cross-contaminating individuals who have not been exposed to such agents.
[0004] Accordingly, there is a need in the art for methods and/or biomarkers useful for detecting and/or measuring the state or condition of a subject, especially based on genomic DNA released into circulation upon pathophysiological insults.
SUMMARY OF THE INVENTION
[0005] The present invention is based, in part, on the discovery that certain nucleotides, e.g., genomic DNA in free circulation of a subject can be used as a biomarker to indicate the state of the subject, e.g., subject's exposure to any pathophysiological insult. Accordingly, the present invention provides methods, kits, and related biomarkers and reagents useful for detecting cell damage associated with a physiopathologica insult.
[0006] In one aspect of the invention, it provides a method for detecting cell damage related to a pathophysiological insult in a subject. The method includes detecting the presence or absence of a free circulating generic biomarker in a biological sample of the subject, wherein the presence of the free circulating generic biomarker is indicative of cell damage related to a pathophysiological insult in the subject.
[0007] The pathophysiological insults can be a physical insult including without any limitation exposure to high levels of irradiation, for example, in a nuclear accident or a bomb attack. In one embodiment, the pathophysiological insult can be due to infectious agents, such as but not limited to infections by viruses, bacteria, and or parasite, either naturally or as a result of bioterrorism. In another embodiment, the pathophysiological insult can be due to the development and progression of a disease state, such as in tumorigenesis, heart, liver, lung or kidney disease. In yet another embodiment, the pathophysiological insult can be a chemical insult such as chemotherapy and other hematotoxic agents, carbon tetrachloride and other hepatotoxic agents, oxidizing agents and acids and other topically or ingested necrotizing agents. In another embodiment, the pathophysiological insult can be a traumatic physical insult such as in head injuries or burns resulting from accidents.
[0008] The free circulating generic biomarker of the present invention comprises nucleotides that are present as free circulating nucleotides or free plasma nucleotides in a subject and are not associated or located within any cell. Examples of generic biomarkers include sequences selected from those having Alu sequence, or sequences derived from telomeres, and genes encoding 18S/28S ribosomal RNA.
[0009] In another aspect, the present invention provides a method for detecting cell damage resulting from a pathophysiological insult comprising determining the level of a free circulating generic biomarker in a biological sample of a subject. In one embodiment, the level of the free circulating generic biomarker relates to a physical insult such as but not limited to exposure to radiation, for example, in a nuclear accident or a dirty bomb attack.
[0010] In another embodiment, the level of the free circulating generic biomarker relates to a pathophysiological insult due to infectious agents such as but not limited to infections by viruses, bacteria, and or parasite, either naturally or as a result of bioterrorism. In another embodiment the level of the free circulating generic biomarker relates to a pathophysiological insult as a result of the development and progression of a disease state, such as in tumorigenesis, heart, liver, lung or kidney disease.
[0011] In yet another embodiment, the level of the free circulating generic biomarker relates to a pathophysiological insult resulting from chemical exposure such as but not limited to an exposures to aerosols from chemical fires and industrial toxin exposure In another embodiment, the level of the free circulating generic biomarker relates to a pathophysiological insult due to a traumatic physical insult such as physical injuries, e.g., head injuries resulting from accidents, sports-related injuries and excessive exercise.
[0012] The present invention also provides a kit for detecting circulating nucleotides, e.g., DNAs due to damage to cells as a result of pathophysiological insults in individuals. In one embodiment, the kit comprises a probe set used for detecting free circulating nucleotides. In one embodiment the probe set comprises sequences that hybridize to the generic biomarkers that are present in the free circulating nucleotides or free plasma nucleotides in a biological samples, such as plasma or other body fluids. Examples of generic biomarkers include sequences selected from those having Alu sequence, sequences derived from telomeres, 18S/28S ribosomal RNA and other genomic DNA sequences.
[0013] In another embodiment, the probe set comprises a capture extender having sequences that hybridize to the generic biomarkers such as but not limited to Alu sequences, telemore sequences or 18S/28S ribosomal RNA sequences present in the free circulating nucleotides or free plasma nucleotides present in a biological sample obtained from a subject. In yet another embodiment, the probe set further comprises a label extender having sequences that hybridize to the generic biomarkers such as but not limited to Alu sequences, telemore sequences or 18S/28S ribosomal RNA sequences that are present in the free circulating nucleotides or free plasma nucleotides present in a biological sample obtained from a subject.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 shows the schematic where DNA is released into the circulation following insults from various pathophysiological processes.
[0015] FIG. 2 shows the schematic for detecting DNA released into the circulation as a result of pathophysiological insults.
[0016] FIG. 3 shows the correlation of relative light units (RLU) emitted from streptavidin-conjugated phycoerythrin labeled probe bound to the generic marker, Alu sequences.
[0017] FIG. 4A shows DNA released into the circulation after total body irradiation of 10 Gy. over a 24-hour period.
[0018] FIG. 4B shows ethidium bromide stained DNA of samples FIG. 3A above.
[0019] FIG. 5 shows the correlation between DNA released into the circulation and radiation dose.
[0020] FIG. 6 shows DNA released into the circulation after total body irradiation of 2 and 5 Gy over a 21-day period.
[0021] FIG. 7 shows DNA released into the circulation for various disease states.
[0022] FIG. 8 shows the correlation between DNA released into the circulation and the presence of creatine-kinase 2 (CK-MB) in a patient with myocardia infarction.
[0023] FIG. 9 shows the effect of D68, a radio-protective agent used for protecting/treating a subject from the effects of radiation.
DETAILED DESCRIPTION OF THE INVENTION
[0024] The present invention is based, in part, on the discovery that certain nucleotides, e.g., genomic DNA in free circulation of a subject can be used as a biomarker to indicate the state of the subject, e.g., subject's exposure to any pathophysiological insult. Accordingly, the present invention provides methods, kits, and related biomarkers and reagents used for detecting cell damage associated with a pathophysiological insult.
[0025] In one aspect of the invention, it provides methods for detecting cell damage as a result of or associated with pathophysiological insults in individuals via detecting the presence or absence of one or more free circulating generic biomarkers in a biological sample obtained from a subject of interest.
[0026] The free circulating generic biomarker of the present invention can be any generic biomaker, e.g., DNA or RNA marker that is released into vascular system, present in circulation, e.g. blood or plasma, present in body fluid, e.g., plasma, serum, urine, or pleural effusion or is extracellular, e.g., outside of (not associated or located within) any cell, bound or unbound to the cell surface. The free circulating nucleotides, e.g., containing generic biomarker(s), as used herein can be used interchangeably with the term “cell free nucleotide”, “cell free circulating nucleotide” or “free circulating nucleotide”, “plasma nucleotide” or “cell free plasma nucleotide”. According to the present invention, free circulating nucleotides, e.g., containing generic biomarkers can be obtained from a biological sample such as but not limited to blood sample, serum sample, plasma sample, urine sample, or a pleural effusion sample or a combination thereof.
[0027] The term “generic biomarkers” as used in the present invention are nucleotides (DNA or RNA) or other biological entities that function as markers associated with cellular release of genetic contents. In general, generic biomarkers are nucleotides, e.g., biomarkers present extracellularly, and optionally whose sequences per se or expressions or activities within cells and/or on cell surfaces does not constitute any significant part of a biomarker, e.g., are not specifically associated with any particular disease or condition. In particular, generic biomarkers of the present invention relies primarily on their extracellularly presence or activity to function as a biomarker.
[0028] In one embodiment, generic biomarkers are markers associated with cell death or cellular release of e.g., genetic contents such as DNA as a result of neoplasia such as cancer. In another embodiment, generic biomarkers are markers associated with cell death or cellular release of, e.g., genetic contents such as DNA as a result of exogenous insult, treatment, or traumatic impact to a subject, e.g., pathogen attack, damaging exposure, physical trauma, etc. In yet another embodiment, generic biomarkers are markers associated with cell death or cellular release of, e.g., genetic content such as DNA as a result of internal trauma or insult in a subject, e.g. cardiac infarction, autoimmune diseases, etc. In still another embodiment, generic biomarkers are markers associated with cell death or cellular release of, e.g., genetic content such as DNA as a result of a pathophysiological insult, but not normal physiological process in a subject, e.g., aging.
[0029] In still yet another embodiment, generic biomarkers are repetitive sequences or elements, e.g., tandem repeats, etc., house keeping genes or elements, or any other sequences that are present in certain abundance in mammalian, e.g., human genomes. For instance, generic biomarkers can be repetitive sequences or any sequence element that constitutes at least 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, or 10% of the human genome.
[0030] In one exemplary embodiment, the generic biomarkers are markers having partial or whole Alu sequences. The Alu sequence is a short stretch of DNA originally characterized by the action of Alu restriction endonuclease, which recognizes the sequence 5′ AG/CT 3′. The Alu sequence belongs to a family of repetitive elements present in mammalian genome such as the human genome. There are roughly over 300,000 Alu family members in the haploid genome. The Alu sequences are about 300 base pair long and there are over one million of these sequences interspersed throughout the human genome. It is estimated that about 10% of the human genome consists of Alu sequences.
[0031] Any Alu sequence, partial or whole can be used as generic biomarkers. In one embodiment, Alu sequences that are most abundant or have substantial abundance in the human genome are used as generic biomarkers. In another embodiment, Alu sequences that are uniquely associated with stress or insults to a subject are used as generic biomarkers.
[0032] Examples of Alu sequences that can be used as generic biomarkers include but are not limited to the sequences represented in SEQ ID NOS: 1 or 2 or fragments thereof. In one embodiment, generic biomarkers of the present invention are about 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% identical to SEQ ID NOS: 1 or 2.
[0033] In a further embodiment, the Alu sequence biomarkers can be detected using a probe set designed based on Alu sequences used as markers, e.g., according to QuantiGene™ methods. In general, a probe set includes a Capture Extender (CE), e.g., at least two, three, four, or five CEs, each containing one of sequences of SEQ ID NOS: 7-19 (See, Tables 1-3 below), a Label Extender (LE), e.g., at least one, two, three, four, or five LEs, each containing one of sequences of SEQ ID NOS: 32-44 (See, Table 6-8 below) and optionally a Blocking Label (BL), e.g., at least one, two, or three BLs each containing one of sequences of SEQ ID NOS: 69-71 (See, Table 11 below).
[0034] The length of CE, LE and BL can be from about 10 nucleotides to about 20 nucleotides in length, from about 20 nucleotide to about 30 nucleotides in length, or from about 30 nucleotides to 50 nucleotides in length. In one embodiment, the probe set includes CEs each containing one of sequences of SEQ ID NOS: 7-11, LEs each containing one of sequences of SEQ ID NOS: 32-35 and optionally a BL containing a sequence of SEQ ID NO: 69. In another embodiment, the probe set includes CEs each containing one of sequences of SEQ ID NOS: 12-15, LEs each containing one of sequences of SEQ ID NOS: 36-38. In yet another embodiment, the probe set includes CEs each containing one of sequences of SEQ ID NOS: 16-19, LEs each containing one of sequences of SEQ ID NOS: 39-44 and optionally BLs each containing one of sequences of SEQ ID NOS: 70 and 71.
[0035] In another exemplary embodiment, the generic biomarkers are markers having partial or whole sequences derived from genes encoding 18S/28S ribosomal RNA. Ribosomal RNA genes are organized in tandem repeats in mammalian genomes. In humans, there are about 300-400 such repeats organized in five clusters. Examples of 18S and 28S sequences that can be used as generic biomarkers include but are not limited to those represented in SEQ ID NOS: 3 or 4 or fragments thereof. In one embodiment, generic biomarkers of the present invention are about 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% identical to SEQ ID NOS: 3 or 4.
[0036] In a further embodiment, the 18S/28S rRNA sequence biomarkers can be detected using a probe set designed based on 18S/28S rRNA sequences used as markers, e.g., according to QuantiGene™ methods. In general, a probe set includes a Capture Extender (CE), e.g., at least two, three, four, or five CEs each containing one of sequences of SEQ ID NOS: 20-31 (See, Tables 4 and 5 below), a Label Extender (LE), e.g., at least one, two, three, four, or five LEs each containing one of sequences of SEQ ID NOS: 45-68 (See, Tables 9 and 10 below) and optionally a Blocking Label (BL), e.g., at least one, two, three, four, or five BLs each containing one of sequences of SEQ ID NOS: 72-77 (See, Table 11 below).
[0037] The length of CE LE and BL can be from about 10 nucleotide to about 20 nucleotide in length, from about 20 nucleotide to about 30 nucleotide in length, or from about 30 nucleotide to 50 nucleotide in length.
[0038] In a further embodiment, the generic biomarkers are markers having partial or whole sequences derived from telomeres. Telomere is involved in the replication and stability of the chromosome. It includes a region of repetitive DNA sequences of about six nucleotide bases at the end of the chromosome. The telomeric sequences can vary between approximately 300 to approximately 600 bp in length in yeast to many kilobases in humans. The sequences typically comprise an array of about 6 to about 8 bp of G-rich repeats, or less, such as TTAGGG, TTGGG, TTTTGGGG, etc. Examples of sequences useful for being used as generic biomarkers include but are not limited to SEQ ID NOS: 5 and 6 and fragments thereof. In one embodiment, generic biomarkers of the present invention are about 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NOS: 5 or 6.
[0039] In a further embodiment, the telomeric sequence biomarkers can be detected using a probe set designed based on telomeric sequences used as markers, e.g., according to QuantiGene™ methods. In general, a probe set includes a Capture Extender (CE), e.g., at least two, three, four, or five CEs, a Label Extender (LE) e.g., at least one, two, three, four, or five LEs, and optionally a Blocking Label (BL), e.g., at least one, two, three, four, or five BLs. The length of CE, LE and BL can be from about 10 nucleotide to about 20 nucleotide in length, from about 20 nucleotide to about 30 nucleotide in length, or from about 30 nucleotide to 50 nucleotide in length.
[0040] The term “pathophysiological insult” as used herein means any physical or pathological impact or trauma, e.g., associated with an exogenous or internal event or source. In one embodiment, the pathophysiological insult is associated with an exogenous stress, impact or treatment to a subject. For example, it can be an instance of pathogen infection, exposure to hazardous material, physical injury, or any external event that is traumatic to a subject's system. In another embodiment, the pathophysiological insult is associated with an internal stress, impact or pathological event to a subject. For example, it can be any pathological event associated with cell death or programmed cell death, necrosis, cellular degradation, etc.
[0041] In one exemplary embodiment, the pathophysiological insult is an exposure to radiation or any other material or energy source that causes DNA damage. In one embodiment, the pathophysiological insult is an exposure to radiation in association with a nuclear incident, attack of nuclear weapon, etc.
[0042] In another embodiment, the pathophysiological insult is a chemical insult such as but not limited to caustic aerosols from industrial accidents or explosions, such as halogenated hydrocarbons or acids. Evaluating the severity of exposure to chemical weapon detonation is another example.
[0043] In another exemplary embodiment, the pathophysiological insult is due to infectious agents, such as but not limited to infections by viruses, bacteria, and or parasite, either by natural exposure to an infectious agent or as a result of bioterrorism.
[0044] Examples of viral families that can result in pathophysiological damage in cells include: Paramyxoviridae (e.g., parainfluenza, mumps, measles); Orthomyxoviridae (e.g., influenza); Hepdnaviridae (e.g., hepatitis); Adenoviridae (e.g., acute respiratory disease); Poxyiridae (e.g., small pox); Herpesviridae (e.g., herpes, Karposi sarcoma); Papillomaviridae (e.g., HPV); Polyomaviridae (e.g., cystitis or mild or acute respiratory diseases); Parvoviridae; Rhabdoviridae (e.g., rabies); Filoviridae (e.g., hemorrhagic fever caused by Ebola virus and Marburg virus); Bunyaviridae (e.g., encephalitis, Hantavirus respiratory syndrome, Rift Valley fever); Arenaviridae (e.g., aseptic meningitis, encephalitis, meningoencephalitis, Lassa fever); Coronaviridae (e.g., severe acute respiratory syndrome or SARS); Flaviviradae (e.g., Dengue hemorrhagic fever); Togaviridae; Picornaviridae (e.g.,); Caliciviridae (e.g., winter vomiting disease); Astroviridae (e.g., gastroenteritis); Retroviridae (e.g., HIV, HTLV) and Reoviridae (e.g., Colorado Tick fever).
[0045] Non-limiting examples of bacteria that can cause pathophysiological damage in infected cells are: B. pertussis; Leptospira Pomona; S. paratyphi A and B; C. diphtheriae, C. tetani, C. botulinum, C. perfringens, C. feseri and other gas gangrene bacteria; B. anthracis; P. pestis; P. multocida; Neisseria meningitides; N. gonorrheae; Hemophilus influenzae; Actinomyces (e.g., Norcardia ); Acinetobacter ; Bacillaceae (e.g., Bacillus anthrasis ); Bacteroides (e.g., Bacteroides fragilis ); Blastomycosis; Bordetella ( Bordetella pertusi ); Borrelia (e.g., Borrelia burgdorferi ); Brucella; Campylobacter; Chlamydia; Coccidioides; Corynebacterium (e.g., Corynebacterium diptheriae ); E. coli (e.g., Enterotoxigenic E. coli and Enterohemorrhagic E. coli ); Enterobacter (e.g. Enterobacter aerogenes ); Enterobacteriaceae ( Klebsiella, Salmonella (e.g., Salmonella typhi, Salmonella enteritidis, Serratia, Yersinia, Shigella ); Erysipelothrix; Haemophilus (e.g., Haemophilus influenza type B); Helicobacter; Legionella (e.g., Legionella pneumophila ); Leptospira; Listeria (e.g., Listeria monocytogenes ); Mycoplasma; Mycobacterium (e.g., Mycobacterium leprae, Mycobacterium tuberculosis and Mycobacterium bovis ); Vibrio (e.g., Vibrio cholerae ); Pasteurellacea ( Pasteurella haemolytica ); Proteus; Pseudomonas (e.g., Pseudomonas aeruginosa ); Rickettsiaceae; Spirochetes (e.g., Treponema spp., Leptospira spp., Borrelia spp.); Shigella spp.; Meningiococcus; Pneumococcus and Streptococcus (e.g., Streptococcus pneumoniae and Groups A, B, and C Streptococci ); Ureaplasmas; Treponema pollidum ; and Staphylococcus ( Staphylococcus aureus and Staphylococcus epidermidis ).
[0046] Non-limiting examples of parasites or protozoa which can cause pathophysiological damage in infected cells include: leishmaniasis ( Leishmania tropica mexicana, Leishmania tropica, Leishmania major, Leishmania aethiopica, Leishmania braziliensis, Leishmania donovani, Leishmania infantum, Leishmania chagasi ); trypanosomiasis ( Trypanosoma brucei gambiense, Trypanosoma brucei rhodesiense ); toxoplasmosis ( Toxoplasma gondii ); schistosomiasis ( Schistosoma haematobium, Schistosoma japonicum, Schistosoma mansoni, Schistosoma mekongi, Schistosoma intercalatum ); malaria ( Plasmodium virax, Plasmodium falciparium, Plasmodium malariae and Plasmodium ovate ); Amebiasis ( Entamoeba histolytica ); Babesiosis ( Babesiosis microti ); Cryptosporidiosis ( Cryptosporidium parvum ); Dientamoebiasis ( Dientamoeba fragilis ); Giardiasis ( Giardia lamblia ); Helminthiasis and Trichomonas ( Trichomonas vaginalis ). The above lists are meant to be illustrative and by no means are meant to limit the invention to those particular bacterial, viral or parasitic organisms.
[0047] In another embodiment, the pathophysiological insult can be due to the development and progression of a disease state, e.g., associated with cell death (programmed cell death), cell damage, necrosis, etc. In one embodiment, the pathophysiological insult is tumorigenesis or neoplasia in a subject. In another embodiment, the pathophysiological insult is substantial tumorigenesis or neoplasia at more than one location in a subject, for example, metastasis in lymph nodes etc. Examples of diseases resulting from tumorigenesis or neoplasia, include but not limited to leukemia, breast cancer, prostate cancer, liver cancer, stomach cancer, colon cancer, melanoma, lymphoma, lung cancer, pancreatic cancer, brain tumor, oral cancer etc.
[0048] In yet another embodiment, the pathophysiological insult is an autoimmune disease. Examples of autoimmune disease include vertiligo, scleroderma, rheumatoid arthritis, Chagas disease, diabetes mellitus type 1, Hashimoto disease, ankylosing spondylitis, Grave's disease, Guillain-Barre Syndrome, etc.
[0049] In yet another embodiment, the pathophysiological insult is a cardiovascular disease. Examples of cardiovascular disease include acute vascular obstruction, such as pulmonary embolism and cardiac infarction resulting in apoptosis of heart cells which in turn causes the release of cell free nucleotides, e.g., DNA into circulation. In yet another embodiment, the pathophysiological insult is hepatic disease, lung disease or kidney disease, etc., especially conditions associated with cell death and necrosis.
[0050] In still another embodiment, the pathophysiological insult is a traumatic physical insult such as head injuries resulting from accidents. In still another embodiment, the pathophysiological insult can be from sports injury, such as in boxing, football or strenuous exercise, etc.
[0051] According to the present invention, the method for detecting cell damage related to a pathophysiological insult in a subject can include qualitative and/or quantitative detection of the cell damage. In one embodiment, the method of the present invention includes detection of presence or absence of one or more free circulating generic biomarkers in a biological sample obtained from a subject, which is exposed to or suspected of being exposed to a pathophysiological insult. In another embodiment, the method of the present invention includes detection of the level of one or more free circulating generic biomarkers in a biological sample obtained from a subject to monitor the progression, the extent or level of, or the effect of the treatment for a pathophysiological insult.
[0052] The method of detection of the present invention can be carried out with or without amplification of the free circulating generic biomarker. In one embodiment, the method of detection can be, but not limited to real-time PCR, quantitative PCR, fluorescent PCR, RT-MSP (RT methylation specific polymerase chain reaction), PicoGreen™ (Molecular Probes, Eugene, Oreg.) detection of DNA, radioimmunoassay, direct radio-labeling of DNA, etc. In another embodiment, the method of detection of the present invention can be carried out without relying on amplification, e.g., without generating any copy or duplication of a target sequence, without involvement of any polymerase, or without the need for any thermal cycling. In yet another embodiment, the method of detection of the present invention is carried out using the principles set forth in the QuantiGene™ method described in U.S. application Ser. No. 11/471,025, filed Jun. 19, 2006, and is incorporated herein by reference.
[0053] The QuantiGene™ method uses a branched DNA technology in a series of hybridization reactions without the need for thermal cycling for amplification of a signal. In principle, it uses a set of primary probes to hybridize to a target sequence and the presence of such hybridization is intensified via additional probes hybridizing to part of these primary probes. In other words, the method intensifies the signal of hybridization by multiple layers of probe hybridization instead of any actual nucleotide sequence amplification.
[0054] In one exemplary embodiment for the branched DNA technology, about 30 or more different oligonucleotide probes are used to bind specifically to a target DNA or RNA. Briefly, a nucleic acid such as free circulating DNA (linear or circular) is captured to a solid support by hybridizing to a set of probes, e.g., Capture Extenders (CEs), which in turn hybridizing to a set of probes, e.g., Capture Probes (CPs) attached to the solid support, e.g., beads, etc. Subsequently another set of probes, e.g., Label Extenders (LEs) can be used to further hybridize to the target nucleotide captured on the solid support. The signal of such hybridization can be intensified either by directly detecting the multiple hybridization of LEs to the target nucleotide on the solid support, or alternatively by further hybridization of one or more set of probes, e.g., pre-Amplifier probe, Amplifier probe, etc. to the hybridized LEs, or both. In one particular embodiment, the detection of such hybridization is carried out using a detectable entity conjugated with streptavidin while the corresponding probes are biotinylated. (See, FIG. 3 )
[0055] In one embodiment, the probe set comprises the Capture Extender and the Label Extender having sequences that recognize and bind to Alu sequences. In another embodiment, the Capture Extender and the Label Extender are designed to recognize and bind to telomeric sequences. In another embodiment, Capture Extender and the Label Extender are designed to recognize and bind to 18S or 28 ribosomal RNA sequences.
[0056] In another aspect of the invention, the method for detecting cell damage resulting from a pathophysiological insult comprises determining the expression profile of a free circulating generic biomarker in a biological sample of a subject. In general, the expression profile of the free circulating generic biomarker of the present invention includes any parameter or data or qualitative or quantitative description associated with the presence or absence of the free circulating generic biomarker.
[0057] In one embodiment, the expression profile of the free circulating generic biomarker includes the level or concentration of one or more free circulating generic biomarkers. In another embodiment, the expression profile of the free circulating generic biomarker includes the presence or absence of a group or combination of free circulating generic biomarkers. In yet another embodiment, the expression profile of the free circulating generic biomarkers includes the level or concentration of one or more free circulating generic biomarkers in relation to a predetermined timeline or a timeline in association with the occurrence of a pathophysiological insult. In yet another embodiment, the expression profile of the free circulating generic biomarkers includes a combination of parameters, e.g., concentration, presence or absence with respect to a pre-determined timeline, extent of cell damage, the nuclear acid release kinetics, the balance between the gene production/fragmentation and the rate of body clearance, etc. In still another embodiment, the expression profile of the free circulating generic biomarkers includes one or more factors such as concentration, timeline, rate of increase, rate of resolution to baseline, peak level, differential expression of different generic markers, and time dependant changes in the differential expression of different generic markers.
[0058] According to another aspect of the present invention, it provides a kit for detecting free circulating generic biomarker due to cell damage as a result of pathophysiological insults in a subject. In one embodiment, the kit comprises a probe set useful for detecting free circulating generic biomarkers. In one embodiment the probe set comprises sequences that hybridize to the free circulating generic biomarkers.
[0059] In one exemplary embodiment, the probe set comprises a capture extender (CE) having sequences that hybridize to the generic biomarkers. In one embodiment, the probe set comprises a capture extender of probe set 1 derived from the Alu sequence of SEQ ID NO: 1. Examples of capture extenders derived from SEQ ID NO: 1 include SEQ ID NOS: 7, 8, 9, 10 and 11. (See, Table 1)
[0000]
TABLE 1
Capture Extender of Probe Set 1 derived from
the Alu sequence of SEQ ID NO: 1.
SEQ ID
CAPTURE EXTENDER NUCLEOTIDE
NO:
SEQUENCE OF PROBE SET 1
7
atttttagtagagacggggtttcaTTTTTctcttggaaa
gaaagt
8
cgcccggctaattttttgtTTTTTctcttggaaagaaagt
9
cgcctcccgggttcacgTTTTTctcttggaaagaaagt
10
ggagtgcagtggcgcgaTTTTTctcttggaaagaaagt
11
cgctctgtcgcccaggctTTTTTctcttggaaagaaagt
[0060] In another embodiment, the probe set comprises a capture extender of probe set 2 derived from the Alu sequence of SEQ ID NO: 1. Examples of capture extender derived from SEQ ID NO: 1 include SEQ ID NOS: 12, 13, 14, 15 (See, Table 2).
[0000]
TABLE 2
Capture Extender of Probe Set 2 derived from
the Alu sequence of SEQ ID NO: 1
SEQ ID
CAPTURE EXTENDER NUCLEOTIDE
NO:
SEQUENCE OF PROBE SET 2
12
cgcccggctaattttttgtatttttagtagagacTTTT
Tctcttggaaagaaagt
13
tctcctgcctcagcctcccgagtagctTTTTTctcttg
gaaagaaagt
14
cgcctcccgggttcacgccatTTTTTctcttggaaaga
aagt
15
gtcgcccaggctggagtgcagtggTTTTTctcttggaa
agaaagt
[0061] In another embodiment, the probe set comprises a capture extender derived from the Alu sequence of SEQ ID NO: 2. Examples of capture extender derived from SEQ ID NO: 2 include SEQ ID NOS: 16, 17, 18 and 19. (See, Table 3).
[0000]
TABLE 3
Capture Extender of Probe Set derived from
the Alu sequence of SEQ ID NO: 2.
SEQ ID
CAPTURE EXTENDER NUCLEOTIDE
NO:
SEQUENCE OF ALU SEQ ID NO: 2
16
caaagtgctgggattacaggcTTTTTctcttggaaa
gaaagt
17
tttcattatattggtcaggctggtTTTTTctcttggaaa
gaaagt
18
gctgggattacaggcacccTTTTTctcttggaaa
gaaagt
19
cgctctgtcgcccaggctTTTTTctcttggaaag
aaagt
[0062] In another embodiment, the probe set comprises a capture extender, which is designed based on the 18S sequence of SEQ ID NO: 3. Examples of capture extenders based on 18S SEQ ID NO: 3 include SEQ ID NOS: 20, 21, 22, 23, 24 and 25. (See, Table 4)
[0000]
TABLE 4
Capture Extender of Probe Set derived from the
18S sequence of SEQ ID NO: 3.
SEQ ID
CAPTURE EXTENDER NUCLEOTIDE
NO:
SEQUENCE OF 18S
20
catggccgttcttagttggtgTTTTTctcttggaaa
gaaagt
21
ggcccggacacggacagTTTTTctcttggaaagaaagt
22
tgaaacttaaaggaattgacggaaTTTTTctcttggaaa
gaaagt
23
gggcagcttccgggaaaTTTTTctcttggaaagaaagt
24
gttattcccatgacccgccTTTTTctcttggaaagaaagt
25
cgaaagtcggaggttcgaagaTTTTTctcttggaaag
aaagt
[0063] In another embodiment the probe set comprises a capture extender which is designed based on the 28S sequence of SEQ ID NO: 4. Examples of capture extenders based on 18S SEQ ID NO: 4 include SEQ ID NOS: 26, 27, 28, 29, 30 and 31. (See, Table 5)
[0000]
TABLE 5
Capture Extender of Probe Set derived from
the 28S sequence of SEQ ID NO: 4.
SEQ ID
CAPTURE EXTENDER NUCLEOTIDE
NO:
SEQUENCE OF 28S
26
ggtgtatgtgcttggctgaggaTTTTTctcttggaa
agaaagt
27
ggaacgtgagctgggtttagaTTTTTctcttggaaa
gaaagt
28
cgacgtcgctttttgatccttTTTTTctcttggaaa
gaaagt
29
gcggccaagcgttcatagTTTTTctcttggaaagaaagt
30
tccttctgaccttttgggttttTTTTTctcttggaaa
gaaagt
31
tcccgtggagcagaagggTTTTTctcttggaaagaaagt
[0064] In another embodiment, the probe set further comprises a label extender having sequences that hybridize to the generic biomarkers. In one embodiment, the probe set comprises a label extender of probe set 1 derived from the Alu sequence of SEQ ID NO: 1. Examples of label extenders derived from SEQ ID NO: 1 include SEQ ID NOS: 32, 33, 35 and 35. (See, Table 6).
[0000]
TABLE 6
Label Extender of Probe Set 1 derived from
the Alu sequence of SEQ ID NO: 1.
SEQ ID
LABEL EXTENDER NUCLEOTIDE
NO:
SEQUENCE OF PROBE SET 1
32
ccgtgttagccaggatggtctTTTTTctgagtcaaagcat
gaagttac
33
tcccgagtagctgggactacaTTTTTctgagtcaaagcat
gaagttac
34
ccattctcctgcctcagccTTTTTctgagtcaaagcatg
aagttac
35
tctcggctcactgcaagctcTTTTTctgagtcaaagcatg
aagttac
[0065] In another embodiment the probe set comprises a label extender of probe set 2 derived from the Alu sequence of SEQ ID NO: 1. Examples of label extender of probe set 2 derived from SEQ ID NO: 1 include SEQ ID NOS: 36, 37, and 38. (See, Table 7)
[0000]
TABLE 7
Label Extender of Probe Set 2 derived from
the Alu sequence of SEQ ID NO: 1.
SEQ
ID NO:
LABEL EXTENDER NUCLEOTIDE SEQUENCE OF PROBE SET 2
36
ggggtttcaccgtgttagccaggatggtctTTTTTctgagtcaaagcatgaagttac
37
gggactacaggcgcccgccaccaTTTTTctgagtcaaagcatgaagttac
38
cgcgatctcggctcactgcaagctcTTTTTctgagtcaaagcatgaagttac
[0066] In another embodiment, the probe set comprises a label extender derived from the Alu sequence of SEQ ID NO: 2. Examples of label extender derived from SEQ ID NO: 2 include SEQ ID NOS: 39, 40, 41, 42, 43 and 44. (See, Table 8).
[0000]
TABLE 8
Label Extender of Probe Set 2 derived
from the Alu sequence of SEQ ID NO: 2.
SEQ ID NO:
LABEL EXTENDER NUCLEOTIDE SEQUENCE OF SEQ ID NO: 2
39
ccaccagcttcggcctccTTTTTctgagtcaaagcatgaagttac
40
ctcaaactcctgacctcaagtgatTTTTTctgagtcaaagcatgaagttac
41
tttttgtatttttagtagagatggggTTTTTctgagtcaaagcatgaagttac
42
gccaccacgcccagctaaTTTTTctgagtcaaagcatgaagttac
43
ctgcctcagcctcccaagtaTTTTTctgagtcaaagcatgaagttac
44
cccaggttcaagcgattctcTTTTTctgagtcaaagcatgaagttac
[0067] In another embodiment, the probe set comprises a label extender, which is designed based on the 18S sequence of SEQ ID NO: 3. Examples of label extenders based on 18S SEQ ID NO: 3 include SEQ ID NOS: 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55 and 56. (See, Table 9)
[0000]
TABLE 9
Label Extender of Probe Set derived from
the 18S sequence of SEQ ID NO: 3.
SEQ
ID NO:
LABEL EXTENDER NUCLEOTIDE SEQUENCE OF 18S
45
gataacgaacgagactctggcatTTTTTgaagttaccgtttt
46
gagcgatttgtctggttaattccTTTTTctgagtcaaagcat
47
gattccgtgggtggtggtgTTTTTgaagttaccgtttt
48
gattgacagattgatagctctttctcTTTTTctgagtcaaagcat
49
caacacgggaaacctcacccTTTTTgaagttaccgtttt
50
gcctgcggcttaatttgactTTTTTctgagtcaaagcat
51
ggggagtatggttgcaaagcTTTTTgaagttaccgtttt
52
ccaaagtctttgggttccggTTTTTctgagtcaaagcat
53
gaccataaacgatgccgaccTTTTTgaagttaccgtttt
54
cgatcagataccgtcgtagttccTTTTTctgagtcaaagcat
55
ccaagaatgttttcattaatcaagaaTTTTTgaagttaccgtttt
56
ggaccagagcgaaagcatttgTTTTTctgagtcaaagcat
[0068] In another embodiment the probe set comprises a label extender which is designed based on the 28S sequence of SEQ ID NO: 4. Examples of label extenders based on 18S SEQ ID NO: 4 include SEQ ID NOS: 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67 and 68. (See, Table 10)
[0000]
TABLE 10
Label Extender of Probe Set derived from
the 28S sequence of SEQ ID NO: 4.
SEQ
LABEL EXTENDER NUCLEOTIDE
ID NO:
SEQUENCE OF 28S
57
catctgtgggattatgactgaacgTTTTTgaagttacc
gtttt
58
gccaatggggcgaagctacTTTTTctgagtcaaagcat
59
gaaccgcaggttcagacatttTTTTTgaagttaccgtt
tt
60
tggtaatcctgctcagtacgagagTTTTTctgagtcaa
agcat
61
cctactgatgatgtgttgttgccaTTTTTgaagttacc
gtttt
62
ccgtcgtgagacaggttagttttacTTTTTctgagtca
aagcat
63
cgttggattgttcacccactaatagTTTTTgaagttac
cgtttt
64
tgtgaagcagaattcgccaagTTTTTctgagtcaaagc
at
65
tttcagtacgaatacagaccgtgaTTTTTgaagttacc
gtttt
66
caaaagctcgcttgatcttgatTTTTTctgagtcaaag
cat
67
agctcagggaggacagaaaccTTTTTgaagttaccgtt
tt
68
cgcaggtgtcctaaggcgTTTTTctgagtcaaagcat
[0069] In another embodiment, the probe set further comprises a blocking label having sequences that hybridize to the generic biomarkers. Examples of blocking label derived from SEQ ID NO: 1 include SEQ ID NO: 69. Examples of blocking label of probe set 2 derived from the Alu sequence of SEQ ID NO: 2 include SEQ ID NOS: 70 and 71. In another embodiment, the probe set comprises a blocking label, which is designed based on the 18S sequence of SEQ ID NO: 3. Examples of blocking label based on 18S SEQ ID NO: 3 include SEQ ID NOS: 72 and 73. In another embodiment the probe set comprises a blocking label is designed based on the 28S sequence of SEQ ID NO: 4. Examples of blocking label based on 28S SEQ ID NO: 4 include SEQ ID NOS: 74, 75, 76 and 77.
[0000]
TABLE 11
Blocking Label Sequence of Alu Sequences of
SEQ ID NOs: 1 and 2, 18S and 28S Sequences.
SEQ ID NO:
BLOCKING LABEL NUCLEOTIDE SEQUENCES
69
ggcgcccgccacca
70
gctcactgcaacctccacct
71
ggagtgcagtggcatgatcttg
72
gggcaccaccaggagtgga
73
ggcgatgcggcggc
74
cgatgtcggctcttcctatcat
75
ccacagggataactggcttgtg
76
aagcaggaggtgtcagaaaagtta
77
aagcggggcctcacga
EXAMPLES
Example 1
[0070] As shown in FIG. 1 , the flow diagram shows the various mechanisms that cause DNA release into the plasma as a result of pathophysiological insults resulting from chemical, radiological or nuclear, biological and explosive exposures.
Example 2
Nucleotide Sequences from which Probe Sets are Designed
[0071]
[0000]
Alu Sequence used for Probe Set Design
(SEQ ID NO: 1)
AGACCATCCTGGCTAACACGGTGAAACCCCGTCTCTACTAAAAATACAA
AAAATTAGCCGGGCGTGGTGGCGGGCGCCTGTAGTCCCAGCTACTCGGG
AGGCTGAGGCAGGAGAATGGCGTGAACCCGGGAGGCGGAGCTTGCAGTG
AGCCGAGATCGCGCCACTGCACTCCAGCCTGGGCGACAGAGCGAGACTC
CGTCT
Alu Sequence used for Probe Set Design
(SEQ ID NO: 2)
AGACCATCCTGGCTAACACGGTGAAACCCCGTCTCTACTAAAAATACAA
AAAATTAGCCGGGCGTGGTGGCGGGCGCCTGTAGTCCCAGCTACTCGGG
AGGCTGAGGCAGGAGAATGGCGTGAACCCGGGAGGCGGAGCTTGCAGTG
AGCCGAGATCGCGCCACTGCACTCCAGCCTGGGCGACAGAGCGAGACTC
CGTCT
18 S Sequence used for Probe Set Design
(SEQ ID NO: 3)
ATGCCAGAGTCTCGTTCGTTATCGGAATTAACCAGACAAATCGCTCCAC
CAACTAAGAACGGCCATGCACCACCACCCACGGAATCGAGAAAGAGCTA
TCAATCTGTCAATCCTGTCCGTGTCCGGGCCGGGTGAGGTTTCCCGTGT
TGAGTCAAATTAAGCCGCAGGCTCCACTCCTGGTGGTGCCCTTCCGTCA
ATTCCTTTAAGTTTCAGCTTTGCAACCATACTCCCCCCGGAACCCAAAG
ACTTTGGTTTCCCGGAAGCTGCCCGGCGGGTCATGGGAATAACGCCGCC
GCATCGCCGGTCGGCATCGTTTATGGTCGGAACTACGACGGTATCTGAT
CGTCTTCGAACCTCCGACTTTCGTTCTTGATTAATGAAAACATTCTTGG
CAAATGCTTTCGCTCTGGTCC
28 S Sequence used for Probe Set Design
(SEQ ID NO: 4)
CGTTCAGTCATAATCCCACAGATGGTAGCTTCGCCCCATTGGCTCCTCA
GCCAAGCACATACACCAAATGTCTGAACCTGCGGTTCCTCTCGTACTGA
GCAGGATTACCATGGCAACAACACATCATCAGTAGGGTAAAACTAACCT
GTCTCACGACGGTCTAAACCCAGCTCACGTTCCCTATTAGTGGGTGAAC
AATCCAACGCTTGGCGAATTCTGCTTCACAATGATAGGAAGAGCCGACA
TCGAAGGATCAAAAAGCGACGTCGCTATGAACGCTTGGCCGCCACAAGC
CAGTTATCCCTGTGGTAACTTTTCTGACACCTCCTGCTTAAAACCCAAA
AGGTCAGAAGGATCGTGAGGCCCCGCTTTCACGGTCTGTATTCGTACTG
AAAATCAAGATCAAGCGAGCTTTTGCCCTTCTGCTCCACGGGAGGTTTC
TGTCCTCCCTGAGCTCGCCTTAGGACACCTGCG
Telomeric Sequence used for Probe Set Design
(SEQ ID NO: 5)
TTAGGG
(SEQ ID NO: 6)
TTTTGGGG
Example 3
Protocol for QuantiGene™ Detection Method
[0072] As shown in FIG. 2 , the schematic shows the method of detection being carried out using the QuantiGene™ method. Briefly, the method involves capturing target circulating DNA from a plasma sample by mixing probe set comprising both the capture extender and label extender with the plasma sample under hybridizing conditions at 55° C. for 30 minutes in 3×SSC, 10% dextransulfate, 0.2% casein, 10 ug/ml polyA and 100 ug/ml denatured salmon sperm DNA. Signal amplification is then carried out by sequentially hybridizing pre-Amplifier, Amplifier and Label Probe at 55° C., 55° C. and 50° C. respectively for 10 minutes each in 3×SSC, 10% dextransulfate, 0.2% casein, 10 ug/ml polyA and 100 ug/ml denatured salmon sperm DNA and with wash buffer: 20 mmol/L Tris-HCL, 400 mmol/L lithium chloride, 1 mL/L Tween 20. The Label Probe may be biotinylated.
Example 4
Correlation of Relative Light Units (RLU) with Alu Sequence Concentration
[0073] Samples containing various concentrations of Alu sequences were incubated with Capture Probe-coated plates together with Alu-specific Capture Extender (CE), Label Extender (LE) and Blocking Label (BL) for 1, 2, 3, 4 h and overnight.
Example 5
Detection of Plasma DNA Over a 24-h Period Following Total Body Irradiation
[0074] As shown in FIG. 4 , an exemplary experiment showing the detection of plasma DNA following total body irradiation in mice. Mice were irradiated with 10 Gy of radiation with Ce 137 irradiator at dose rate of 1.83 Gy/min. At 0, 3, 6, 9, 12 and 24 hours following irradiation, plasma samples were taken from the mice and diluted at 1:10 with distilled water. Two, five, ten and twenty μL of the diluted samples were taken for analysis following the protocol described in Example 2 above. Free plasma DNA released from the cells as a result of damage due to radiation exposure was measured using probe set containing Alu sequences:
[0000]
mouse probeset:
B4galnt2_alu.29.45.CE CEtgcctcccgagtgctggTTTTTctcttggaaagaaagt
B4galnt2_alu.46.65.CE CEctcagaaatccgcctgcctcTTTTTctcttggaaagaaagt
B4galnt2_alu.66.84.CE CEagaccaggctggcctcgaaTTTTTctcttggaaagaaagt
B4galnt2_alu.108.129.CECEagacagggtttctctgtagcccTTTTTctcttggaaagaaagt
B4galnt2_alu.8.28.LE LEgattaaaggcatgcaccaccaTTTTTctgagtcaaagcatgaagttac
B4galnt2_alu.85.107.LE LEtggtgtcctggaactcactctgaTTTTTctgagtcaaagcatgaagttac
mouse seq:
>B4galnt2_alu
CCGGGCATGGTGGTGCATGCCTTTAATCCCAGCACTCGGGAGGCAGAGGCAGGCGGATTT
CTGAGTTCGAGGCCAGCCTGGTCTTCAGAGTGAGTTCCAGGACACCAGGGCTACAGAGAA
ACCCTGTCT
[0075] The results in FIG. 4A showed an increase in plasma DNA from a 5 μL of 1:10 diluted samples over time using the method described in the present invention. The amount of free plasma DNA peaked at 9 h post irradiation.
[0000] FIG. 4B confirmed the results obtained by running the samples in a 2% agarose gel followed by staining with ethidium bromide.
Example 6
Free DNA Released into Plasma Increased with Radiation Dose
[0076] The radiation dose response measuring the amount of free circulating generic biomarker, using the Alu-like sequence in mice (the B1 sequence) and the appropriate sequence probe set and the QuantiGene™ method of detection described in Example 2 above is shown in FIG. 5 . Plasma samples were obtained from mice 9 h post total body irradiation with gamma radiation generated by a 137Cs source at 0, 2, 4, 6, 8, and 10 Gy. The amount of free circulating Alu biomarker released into the plasma were measured using the QuantiGene™ detection method described in Example 2 above with Alu sequence probe set
[0000]
mouse probeset:
B4galnt2_alu.29.45.CE CEtgcctcccgagtgctggTTTTTctcttggaaagaaagt
B4galnt2_alu.46.65.CE CEctcagaaatccgcctgcctcTTTTTctcttggaaagaaagt
B4galnt2_alu.66.84.CE CEagaccaggctggcctcgaaTTTTTctcttggaaagaaagt
B4galnt2_alu.108.129.CECEagacagggtttctctgtagcccTTTTTctcttggaaagaaagt
B4galnt2_alu.8.28.LE LEgattaaaggcatgcaccaccaTTTTTctgagtcaaagcatgaagttac
B4galnt2_alu.85.107.LE LEtggtgtcctggaactcactctgaTTTTTctgagtcaaagcatgaagttac
mouse seq:
>B4galnt2_alu
CCGGGCATGGTGGTGCATGCCTTTAATCCCAGCACTCGGGAGGCAGAGGCAGGCGGATTT
CTGAGTTCGAGGCCAGCCTGGTCTTCAGAGTGAGTTCCAGGACACCAGGGCTACAGAGAA
ACCCTGTCT
[0077] The results showed that the amount of free plasma DNA measured using the Alu sequences, released into circulation increased with increase radiation dose. Statistical analysis showed that even at lower doses of 2, 4, and 6 Gy, a significant difference (P<0.05) can be detected between the different radiation dose and background DNA levels in un-irradiated mice (healthy mice) can be distinguished. The results also show that the generic biomarker used in this assay was sufficiently sensitive for detection of radiation exposure within 9 h of exposure.
Example 7
Sub-Acute and Latent Effect is Dependent on Radiation Dose
[0078] The time course for free plasma DNA in the circulation was shown in FIG. 6 to illustrate the sub-acute and latent effects of two different radiation doses measured over time following total body irradiation of mice (2 and 5 Gy using gamma radiation from a 137Cs source Free plasma DNA was measured using the QuantiGene™ method of detection described in Example 2
[0000]
mouse probeset:
B4galnt2_alu.29.45.CE CEtgcctcccgagtgctggTTTTTctcttggaaagaaagt
B4galnt2_alu.46.65.CE CEctcagaaatccgcctgcctcTTTTTctcttggaaagaaagt
B4galnt2_alu.66.84.CE CEagaccaggctggcctcgaaTTTTTctcttggaaagaaagt
B4galnt2_alu.108.129.CECEagacagggtttctctgtagcccTTTTTctcttggaaagaaagt
B4galnt2_alu.8.28.LE LEgattaaaggcatgcaccaccaTTTTTctgagtcaaagcatgaagttac
B4galnt2_alu.85.107.LE LEtggtgtcctggaactcactctgaTTTTTctgagtcaaagcatgaagttac
mouse seq:
>B4galnt2_alu
CCGGGCATGGTGGTGCATGCCTTTAATCCCAGCACTCGGGAGGCAGAGGCAGGCGGATTT
CTGAGTTCGAGGCCAGCCTGGTCTTCAGAGTGAGTTCCAGGACACCAGGGCTACAGAGAA
ACCCTGTCT
[0079] As shown in FIG. 6A , in plasma of mice exposed to 2 Gy radiation, the amount of free DNA detected in the circulation decreased two-fold 21-days after irradiation. On the other hand in FIG. 6B , mice exposed to 5 Gy irradiation continued to increase in the amount of free plasma DNA in the circulation 21-days after irradiation. The results show that the levels of free plasma DNA can be used to predict the level of damage to the cells following radiation exposure and the method described in the present invention can be used to monitor the course of the damage resulting from pathophysiological insults such as that caused by radiation.
Example 8
Increased Free Plasma DNA Levels Detected in Different Disease States
[0080] The plasma was taken from the same plasma tube of patients who was diagnosized as MI according to the elevated plasma CK-MB, and then tested with human Alu kit. A close correlation was observed.
Human plasma samples were collected and 10 ul of plasma was used for each test. Probe sets are list below.
[0000]
SEQ
CAPTURE EXTENDER NUCLEOTIDE
ID NO:
SEQUENCE OF PROBE SET 1
7
atttttagtagagacggggtttcaTTTTTctcttggaaagaaagt
8
cgcccggctaattttttgtTTTTTctcttggaaagaaagt
9
cgcctcccgggttcacgTTTTTctcttggaaagaaagt
10
ggagtgcagtggcgcgaTTTTTctcttggaaagaaagt
11
cgctctgtcgcccaggctTTTTTctcttggaaagaaagt
[0000]
SEQ
LABEL EXTENDER NUCLEOTIDE
ID NO:
SEQUENCE OF PROBE SET 1
32
ccgtgttagccaggatggtctTTTTTctgagtcaaagcat
gaagttac
33
tcccgagtagctgggactacaTTTTTctgagtcaaagcat
gaagttac
34
ccattctcctgcctcagccTTTTTctgagtcaaagcatga
agttac
35
tctcggctcactgcaagctcTTTTTctgagtcaaagcatg
aagttac
[0000]
SEQ ID NO:
BLOCKING LABEL NUCLEOTIDE SEQUENCES
69
ggcgcccgccacca
70
gctcactgcaacctccacct
71
ggagtgcagtggcatgatcttg
72
gggcaccaccaggagtgga
73
ggcgatgcggcggc
74
cgatgtcggctcttcctatcat
75
ccacagggataactggcttgtg
76
aagcaggaggtgtcagaaaagtta
77
aagcggggcctcacga
[0081] As shown in FIG. 7 , the levels of free plasma DNA was shown to be higher in samples obtained from human subjects with leukemia (LM), diabetes mellitus (DM), cancer (CA), myocardia infarction (M), acute pancreatitis (AP), HBV (hepatitis B), and HCV (hepatitis C) as compare to the level of free plasma DNA in samples from healthy individuals (N).
Example 9
Free Plasma DNA Levels Correlates with Levels of Creatine Kinase 2 (CK-MB) in Patient with Myocardia Infarction
[0082] The plasma was taken from the same plasma tube of patients who was diagnosized as MI according to the elevated plasma CK-MB, and then tested with human Alu kit. A close correlation was observed.
Human plasma samples were collected and 10 ul of plasma was used for each test. Probe sets are list below.
[0000]
SEQ
CAPTURE EXTENDER NUCLEOTIDE
ID NO:
SEQUENCE OF PROBE SET 1
7
atttttagtagagacggggtttcaTTTTTctcttggaaagaaagt
8
cgcccggctaattttttgtTTTTTctcttggaaagaaagt
9
cgcctcccgggttcacgTTTTTctcttggaaagaaagt
10
ggagtgcagtggcgcgaTTTTTctcttggaaagaaagt
11
cgctctgtcgcccaggctTTTTTctcttggaaagaaagt
[0000]
SEQ
LABEL EXTENDER NUCLEOTIDE
ID NO:
SEQUENCE OF PROBE SET 1
32
ccgtgttagccaggatggtctTTTTTctgagtcaaagcat
gaagttac
33
tcccgagtagctgggactacaTTTTTctgagtcaaagcat
gaagttac
34
ccattctcctgcctcagccTTTTTctgagtcaaagcatga
agttac
35
tctcggctcactgcaagctcTTTTTctgagtcaaagcatg
aagttac
[0000]
SEQ ID NO:
BLOCKING LABEL NUCLEOTIDE SEQUENCES
69
ggcgcccgccacca
70
gctcactgcaacctccacct
71
ggagtgcagtggcatgatcttg
72
gggcaccaccaggagtgga
73
ggcgatgcggcggc
74
cgatgtcggctcttcctatcat
75
ccacagggataactggcttgtg
76
aagcaggaggtgtcagaaaagtta
77
aagcggggcctcacga
[0083] The results in FIG. 8 showed that the amount of free plasma DNA released into the circulation correlated with the presence of creatine kinase 2 (CK-MB) in patient with myocardia infarction. Furthermore, the results also show that that the assay is just as reliable as the well-established assay using CK-MB for detection of myocardia infarction.
Example 10
Treatment with D68, a Radio-Protective Agent Reduces Free Plasma DNA in the Circulation of Irradiated Mice
[0084] BALB/c mice (5 per group) exposed to total body irradiation of 10 Gy (gamma irradiation from a 137Cs source) were treated with saline (control) and 350 mg/kg of D68, a radio-protective agent (University of Rochester, N.Y., Department of Radiation Oncology). International Patent Application No. PCT/US2008/064872. Based on U.S. Provisional Patent Application No. 60/940,396, the patent application is herein incorporated by reference. Plasma samples from the mice were collected 9-h post-irradiation and the amount of free plasma DNA present in circulation is measured using the QuantiGene™ method of detection described in Example 2 using the Alu-like B1 sequence derived probe set of human Alu probe set.
[0085] FIG. 9 showed the effect of D68, a radio-protective agent on the levels of free plasma DNA in the circulation of irradiated mice treated with D68 as compared to saline-treated control mice (NS). Irradiated mice treated with D68 had reduced levels of free plasma Alu DNA in the circulation compared to irradiated mice treated with saline, consistent with their lowered sensitivity to irradiation due to the agent.
[0086] All publications, patents and patent applications herein are incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.
[0087] The foregoing detailed description has been given for clearness of understanding only and no unnecessary limitations should be understood therefrom as modifications will be obvious to those skilled in the art. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed inventions, or that any publication specifically or implicitly referenced is prior art.
[0088] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
[0089] While the invention has been described in connection with specific embodiments thereof, it will be understood that it is capable of further modifications and this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth and as follows in the scope of the appended claims. | This invention relates generally to methods for detecting cell damage as a consequence of pathophysiological or traumatic insults such as in a nuclear accident, bioterror attack, tumorigenesis, infections or in individuals with cardiovascular disease. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of application Ser. No. 12/976,534, filed Dec. 22, 2010, now U.S. Pat. No. 8,622,039, issued Jan. 7, 2014, which application and patent are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] This invention relates to desmodromic valve systems, and more particularly to desmodromic valve systems which provide direct bidirectional displacement of a valve stem without the aid of a rocker arm.
[0003] A desmodromic valve system positively opens and closes a valve in an internal combustion engine. This is in contrast to the conventional system in which the valve is positively opened with a cam but closed with a return spring.
[0004] The main benefit of a desmodromic system is the prevention of valve float. In traditional spring valve actuation, as engine speed increases, the inertia of the valve tends to overcome the spring's ability to close the valve completely before the piston reaches TDC (Top Dead Center). In severe cases, the piston contacts the open valve and causes damage to both engine parts. More generally, if a valve does not completely return to its seat before combustion begins, it can allow combustion gases to escape prematurely, leading to a reduction in cylinder pressure which causes a major decrease in engine performance. This can also overheat the valve, possibly warping it and leading to catastrophic failure. The traditional remedy for valve float is to use a stiffer return spring. This increases the seat pressure of the valve, i.e., the static pressure that holds the valve closed, and reduces valve float at higher engine speeds. However, the engine has to work harder to open the valve. The higher forces between spring and cam cause higher stress on the parts resulting in higher temperature and faster wear or failure in the valve drive system. A desmodromic system can avoid the problem to some extent because, although it has to work against the inertia of the valve opening and closing, it does not have to overcome the energy of the spring.
[0005] Despite their advantages, desmodromic valve drive systems have had limited success in commercial application for various reasons such as design complexity, poor reliability, and valve train binding. Numerous approaches to the various problems have been taken since the earliest days of engine development, more than a hundred years ago, as evidenced by the following patents:
[0000]
Patent No.
Inventor(s)
Issue Date
1,644,059
Holle
Oct. 24, 1927
1,937,152
Jünk
Nov. 28, 1933
3,183,901
Thuesen
May 18, 1965
3,430,614
Meacham
Mar. 4, 1969
4,711,202
Baker
Dec. 8, 1987
4,763,615
Frost
Aug. 16, 1988
4,887,565
Bothwell
Dec. 19, 1989
5,048,474
Matayoshi et al.
Sep. 17, 1991
5,058,540
Matsumoto
Oct. 22, 1991
6,276,324
Adams et al.
Aug. 21, 2001
6,487,997
Palumbo
Dec. 3, 2002
6,948,468
Decuir
Sep. 27, 2005
6,951,148
Battlogg
Oct. 4, 2005
[0006] However, presently, all known desmodromic valve designs have drawbacks which make them undesirable for use in several significant applications, such as production automobiles, and there is no obvious path to a better solution.
SUMMARY OF THE INVENTION
[0007] The present invention provides a rockerless desmodromic valve system comprising a first cam rotating on a camshaft and cyclically pushing a valve stem, a second cam on the camshaft, and a band extending circumferentially around the second cam and engaging the valve stem, the second cam rotating within the band and causing it to reciprocate so as to cyclically lift the valve stem. The system preferably but not necessarily has a wide band in the form of a basket large enough to encompass multiple cams and to extend completely around them circumferentially.
[0008] Another aspect of the invention is a desmodromic valve system comprising a semirigid band, which may be in basket form, disposed about a camshaft of an internal combustion engine, the semirigid band attached to a valve stem and constrained to motion along the valve stem axis. The system includes rotatable cam means mounted on the camshaft and disposed within the band for coacting with it without substantially changing its shape to positively drive the valve stem in both directions along its axis and thereby provide reciprocating valve action with positive bidirectional drive.
[0009] The objects and advantages of the present invention will be more apparent upon reading the following detailed description in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIGS. 1-5 depict a first embodiment of a rockerless desmodromic valve system according to the present invention. This embodiment includes a semirigid band or “basket” that substantially surrounds a set of cams on a camshaft and engages paired side cams and an associated valve stem so as to pull the valve stem after it is pushed by a central cam. The basket and cams, which are drawn to scale for a nominal ½ inch valve lift, cooperate to provide reciprocating valve action with positive bidirectional drive.
[0011] FIG. 1 is a side view of the assembly with the valve closed, and with the basket and two side cam followers shown in longitudinal cross-section.
[0012] FIG. 2 is a transverse cross-section along line 2 - 2 of FIG. 1 .
[0013] FIG. 3 is a transverse cross-section along line 3 - 3 of FIG. 4 .
[0014] FIG. 3A is a transverse cross-section like that of FIG. 3 but with the central cam partially cut away to show the shape of an alternative side cam.
[0015] FIG. 4 is a longitudinal cross-section of the assembly with the valve open.
[0016] FIG. 5 is a bottom view of the basket alone, taken along line 5 - 5 of FIG. 1 .
[0017] FIG. 6 shows reference points on the central cam and one side cam pertaining to the relationship between the cam radii in a preferred embodiment of the present invention.
[0018] FIGS. 7-10 depict a second embodiment of a rockerless desmodromic valve system according to the present invention. Like the first embodiment, this embodiment includes a semirigid band or “basket” and a set of cams including a central cam and a pair of side cams. The basket and cams in this case are drawn to scale for a nominal ¼ inch valve lift.
[0019] FIG. 7 is a side view of the assembly with the valve closed, and with the basket and two side cam followers shown in longitudinal cross-section.
[0020] FIG. 8 is a transverse cross-section along line 8 - 8 of FIG. 7 .
[0021] FIG. 9 is a transverse cross-section along line 9 - 9 of FIG. 10 .
[0022] FIG. 10 is a longitudinal cross-section of the assembly with the valve open.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0023] For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
[0024] FIGS. 1-5 , wherein like numerals represent like parts throughout the several views, depict a first embodiment 10 of a rockerless desmodromic valve system according to the present invention. In this embodiment, which is to be understood as one example of a desmodromic valve system according to the present invention, a central cam 12 and a parallel pair of side cams 14 are fixedly mounted on a camshaft 15 so as to rotate therewith, and are substantially surrounded by a semirigid band or “basket” 16 which does not rotate with the camshaft and is constrained by the cams and by its attachment to the stem 20 of a valve 22 . Except as described herein, the camshaft and valve may be conventional parts mounted in a conventional manner in the cylinder head of an internal combustion engine in which each valve has an associated port 24 and has a valve guide (not shown) which closely surrounds the valve stem.
[0025] Basket 16 engages paired side cams 14 and the associated valve stem 20 so as to pull the valve stem after it is pushed by central cam 12 . The basket and cams cooperate to provide reciprocating valve action with positive bidirectional drive. That is, the system positively drives the valve from its closed position, illustrated in FIGS. 1 and 2 , to its open position, illustrated in FIGS. 3 and 4 , by conventional cam action by means of cam 12 in contact with the valve stem, and positively drives the valve back to its closed position using the basket, which is secured to the valve stem and raised by paired cams 14 acting through associated cam followers 18 .
[0026] Each cam 14 has a main portion 14 a with a concavo-convex cross-section, and a peripheral portion or shoulder 14 b with a circular cross-section. The concavo-convex cross-section of the main portion of cam 14 is readily apparent in FIGS. 2 and 3 . In FIGS. 1 and 2 , the concave part 14 c of main portion 14 a of cam 14 is below the camshaft axis (and axially separated from the valve stem), and the convex portion engages the associated cam follower 18 and thereby holds the basket in its raised position. Cams 12 and 14 operate in coordinated fashion such that, at this point in the cycle, lobe 12 a of cam 12 is oriented away from the valve stem and thereby allows the valve to be lifted and thus closed by the basket. Conversely, in FIGS. 3 and 4 , part 14 c of cam 14 is above the camshaft axis and lobe 12 a of cam 12 is oriented toward the valve stem, whereby cam follower 18 —and thus basket 16 —is in its lowest position and the valve is open. A cam follower, such as a snug-fitting cup (not shown), is preferably also provided on the upper end of the valve stem for contact with cam 12 .
[0027] As one example of a set of suitable dimensions for valve system 10 , cam 12 may have a maximum radius of 1 inch (at the outermost point on lobe 12 a ) and a minimum radius of ½ inch, thereby producing a valve lift—the valve displacement between open and closed positions—of ½ inch. Cam portion 14 a has the same maximum and minimum radii as cam 12 , and its radius at any given point is a function of the radius of cam 12 at a diametrically opposed point. Specifically, cam 12 and cam portion 14 a are designed such that, at any two diametrically opposed points X and Y on their respective surfaces (see FIG. 6 ),
[0000]
r
x
+r
y
=c
[0028] The cams are thus complementary. With the above example dimensions, the sum of the radius of cam 12 and the radius of cam portion 14 a at such points X and Y is 1.5″. For example, the outermost point on lobe 12 a is diametrically opposed to the center of concave part 14 c of cam 14 , and the respective radii at those points are 1.0″ and 0.5″, the sum of which is 1.5″.
[0029] Basket 16 has a retainer 26 integrally formed in a reinforced bottom portion thereof. The retainer cooperates with a plurality of keys or keepers 28 to secure the basket to the valve stem. The retainer has a downwardly tapered hole and the keepers are likewise downwardly tapered such that the retainer and associated keepers together form a valve stem lock. The keepers are shaped so as to extend into the groove of the valve stem and are held therein by wedging action of the cooperatively tapered portion of the retainer. The retainer may alternatively be formed as a separate part fitted into a hole in the basket. Examples of retainer/keeper sets are disclosed in U.S. Pat. Nos. 4,327,677 and 4,922,867, which are incorporated herein by reference.
[0030] In an alternative embodiment suited for valves in which the groove is closer to the tip of the stem than in the first embodiment, the retainer is formed in the top of a hollow conical member extending up from the bottom of the basket enough to enclose the groove. The system may also provide an extension of the valve guide as additional lateral support for the stem in retrofit applications involving removal of a return spring. In cases with replaceable valve guides, a longer valve guide may be installed which extends into the space formerly occupied by the return spring. In other cases, e.g., heads with cast guides, the guide may be drilled and tapped to receive a threaded cylindrical extension, preferably with an oil seal and/or a roller guide on top.
[0031] The basket also includes a reinforced upper portion or flange 16 a adjacent each axial end for a cam follower 18 , the flange and cam follower having complementary shapes for retaining the cam follower as shown in FIGS. 2 and 3 . A hole 17 is provided in the top of the basket for insertion of the cam followers. The cam follower may comprise a roller.
[0032] The basket preferably has a unitary, or monocoque, construction, with solid side walls and open ends, and is semirigid, i.e., slightly flexible but sufficiently rigid that it experiences less than 1% elongation in response to forces applied to it during a cycle of operation of the valve to which it is connected—including in particular the forces applied in the process of returning the valve to its closed position—at camshaft speeds from zero to 5,000 RPM. For example, a basket with a nominal height of 2.5″ experiences elongation of less than 0.025″ as it pulls the valve stem to close the valve at camshaft speeds up to 5,000 RPM. Basket elongation is the primary contributor to the dynamic lash of the valve, which is understood to be the variable lash occurring in operation, i.e., the clearance between the valve stem and cam 12 during operation. Basket elongation of up to 0.100″ may be suitable with certain engine designs, but the basket is preferably sufficiently rigid that it limits the dynamic lash to 0.020-0.030″, more preferably less than 0.010″ and, most preferably, 0.005″ or less. One suitable material is thin-wall cast titanium. There is preferably a gap between the bottom portion of the basket and shoulder 14 b when the valve is closed ( FIG. 2 ) and, likewise, a gap between the top portion of the basket and shoulder 14 b when the valve is open ( FIGS. 3 and 4 ). The basket is preferably dimensioned to provide a gap of at least 0.001″ at substantially all points between it and cam 14 at rest.
[0033] The assembly process begins by mounting the baskets on the camshaft before the camshaft is installed in the head. The baskets are moved axially over the cams on the camshaft to their respective cams 12 and 14 . When all the baskets are so mounted, the camshaft is placed in the bearing blocks in the head and secured. Each valve is then installed by sliding its stem through a valve guide and through the hole in the bottom of an associated basket. With the cams oriented as shown in FIG. 2 , the stem is advanced and the basket is lowered as necessary for the groove in the stem to pass beyond the retainer in the basket, and the keepers are then inserted through one or both open ends of the basket and placed in the groove, after which the retainer is moved into place surrounding the keepers, thereby holding them in the groove. Each cam follower 18 is then inserted through the hole 17 in the top of the basket and slid into a flange 16 a, where it is preferably secured in place with a fastener, e.g., screw 19 , extending into the flange through the top of the basket. Screws 19 are preferably aircraft bolts with anti-rotation features, e.g., drilled heads having a common safety wire through them. The top of the cam follower may be tapered in the direction away from hole 17 to provide a wedge shape to facilitate insertion into the flange. Insertion of cam follower 18 pre-loads the valve stem and tensions, i.e., slightly stretches or elongates, the basket. Cam follower 18 is suitably dimensioned to perform this function.
[0034] In operation, starting from the valve-closed position shown in FIGS. 1 and 2 , the camshaft rotates nearly 135° to a point at which cam lobe 12 a begins to engage the valve stem and cam follower 18 simultaneously begins to engage a smaller-radius portion of cam portion 14 a. Cam lobe 12 a then exerts a downward force on the valve stem until the camshaft has rotated 180°, to the valve-open position shown in FIG. 3 . The valve stem is free to move down because cam follower 18 engages the smaller-radius portion of cam portion 14 a, including concave part 14 c, during this part of the cycle, and the valve stem pulls the basket down with it as shown in FIG. 3 . Further camshaft rotation causes cam lobe 12 a to rotate away from the valve stem and correspondingly brings cam follower 18 into contact with points of progressively larger radius on cam portion 14 a. Cam portion 14 a thereupon exerts an upward force on cam follower 18 which lifts the basket, which in turn pulls the valve stem up. When the camshaft has rotated a little more than 45° from the position shown in FIG. 3 , cam follower 18 again bears against the maximum-radius portion of cam portion 14 a and the valve is closed. The valve and basket positions at this point are as shown in FIGS. 1 and 2 and remain so for the remainder of the cycle. It will be understood that the above-mentioned angles of 135° and 45° are mere examples and that the angles at which cam lobe 12 a engages and disengages from the valve stem are functions of desired cam action for a desired valve application.
[0035] The circular peripheral portions 14 b of cam 14 are provided to resist flexing of the basket and thereby limit its maximum elongation as the valve closes, at which time the concave part 14 c of cam 14 moves toward one side of the basket and opens up a significant gap. By virtue of their fixed 1″ radius, portions 14 b maintain a minimum of 2″ spacing between the opposed sides of the basket at least where they make contact with it. Portions 14 b (shoulders) may be on either or both sides of each side cam 14 on the camshaft axis, i.e., the side closer to the central cam, the opposite side, or both. The side closer to the central cam is closer to the line of force (tension) between stem 22 and cam follower 18 during valve closure. Alternatively, a constant-radius disc such as portion 14 b may be provided on either or both sides of central cam 12 , and such a disc may help with camshaft balancing.
[0036] In an alternative embodiment, the desmodromic valve system has a parallel pair of rings or bands instead of the basket described above. The bands are preferably joined at the bottom by a bridge which includes a retainer such as described above, in a unitary construction or as separate parts. A single band with a single cam 14 is also contemplated.
[0037] The basket with cam follower(s) 18 is effectively a clamp. In cooperation with cam(s) 14 , it clamps the central cam (cam 12 ) to the valve stem, whereby the valve stem is virtually an ideal cam follower throughout the valve cycle. It is strongly preferred to have the clamp extend completely around the central cam circumferentially as shown in the drawings and described above. However, in some applications, it may be adequate for the clamp to extend around the cam on only one side of the camshaft, i.e., the left or right side as viewed in FIG. 2 , akin to a C-clamp, with curved or straight vertical and horizontal segments. The clamp may comprise one half of the basket described above, i.e., the left or right half as viewed in FIG. 2 , but including the full retainer and keys and the cam followers as described above. The cam followers may be fixed in position in supporting flanges as described above, or may be vertically adjustable by means of a threaded connection to the top of the clamp or otherwise. Alternatively, the cam followers may be integral parts of the clamp. Such a clamp is provided, if necessary, with suitable means to keep it aligned with the valve stem. For example, a horizontal support bar or guard rail may be provided on the head so as to abut the back side of the half basket (the side opposite the cam) at the level of the camshaft axis. The support bar may, for example, be bolted or otherwise secured to adjacent bearing blocks.
[0038] As an alternative to the half basket just described, a clamp in the form of a half ring akin to a C-clamp may be adequate in some applications. This clamp may have approximately the same width along the camshaft axis as cam 14 , and be aligned with that cam, but have an axial projection rigidly connecting it to the valve stem. It may have the same general cross-sectional shape as the left or right half of the basket as viewed in FIG. 2 . If necessary, a horizontal support bar or guard rail, as described above, is provided which includes a vertical guide, such as a slot to receive the back of the clamp, to keep the clamp vertically aligned.
[0039] Cams 12 and 14 have complementary shapes as described above, and they are preferably complementary around their entire circumferences, but may be partially complementary in certain applications. It is particularly advantageous for cam 14 to complement cam 12 for the valve-closing portion of the valve cycle, so as to generate a lifting force via the basket or other clamp as soon as the maximum-radius portion of cam lobe 12 a is past the valve stem. However, an upward force is not necessarily required from the basket during every part of the valve cycle, e.g., during the compression stroke and power stroke of a four-stroke engine, and so, in some applications, the side cam may have a relatively small radius for a significant part of its circumference corresponding to such parts of the cycle (and thus have less rotating mass), provided that the basket is suitably secured to the valve stem and kept aligned with it. The basket may be secured by means of a cap screwed over the keys to keep them in place, or, for some applications, a threaded connection without keys may be adequate. A horizontal support bar or guard rail as described above may be provided on each side of the basket for alignment purposes if necessary.
[0040] One example of such a side cam is cam 14 a ′ in FIG. 3A . Cam 14 a ′ is designed for clockwise rotation. It extends approximately 120° around the camshaft as illustrated, and it has the same radius as cam 14 a of the first embodiment for approximately 90°, in the circumferential range from point A to point B, which includes the valve-closing portion of the valve cycle. Those skilled in the art will appreciate that cam 14 a ′ and cam 12 are complementary for that part of the valve cycle. This embodiment preferably includes a circular portion 14 b joined to cam 14 a ′ and having a constant 1″ radius as in the first embodiment. A counterweight 30 is optionally provided on the opposite side of the camshaft from cam 14 a ′ for balancing purposes, and may be mounted on portion 14 b as shown. Camshaft balance can also be achieved by removing weight, e.g., by machining away areas of portion 14 b adjacent to cam 14 a ′, and/or by initially forming such adjacent areas and cam 14 a ′ itself with apertures therein, such as in a spoked wheel. Camshaft balance can be achieved by adding or deleting material or a combination of the two.
[0041] Depending on the rigidity of the basket, portion 14 b may be made with a greater axial width (along the camshaft axis) than portion 14 b in the first embodiment, for purposes of structural integrity. Alternatively, a cam 14 may have a part 14 a ′ (as in FIG. 3A ) with the axial width of original part 14 a (see FIG. 1 ), and also include the remainder of original part 14 a but with half its width, whereby some part of cam 14 engages cam follower 18 throughout the cycle, thus maintaining the pre-load on the valve stem and reinforcing portion 14 b.
[0042] Another embodiment 110 of the invention is depicted in FIGS. 7-10 , wherein like numerals represent like parts throughout the several views. This embodiment and variations thereof may be the same as the embodiment of FIGS. 1-5 and its variations as discussed above, with exceptions as discussed below. A central cam 112 and a parallel pair of side cams 114 are fixedly mounted on a camshaft 115 so as to rotate therewith, and are substantially surrounded by a semirigid band or “basket” 116 which does not rotate with the camshaft and is constrained by the cams and by its attachment to the stem of a valve 122 .
[0043] The primary difference with this embodiment is that the basket and cams are designed for a ¼ inch valve lift. Basket 116 engages paired side cams 114 and the associated valve stem so as to pull the valve stem after it is pushed by central cam 112 . The basket and cams cooperate to provide reciprocating valve action with positive bidirectional drive. That is, the system positively drives the valve from its closed position, illustrated in FIGS. 7 and 8 , to its open position, illustrated in FIGS. 9 and 10 , by conventional cam action by means of cam 112 in contact with the valve stem, and positively drives the valve back to its closed position using the basket, which is secured to the valve stem and raised by paired cams 114 acting through associated cam followers 118 .
[0044] Each cam 114 has a main portion with a concavo-convex cross-section, and a peripheral portion or shoulder with a circular cross-section. In FIGS. 7 and 8 , the concave part of cam 114 is below the camshaft axis (and axially separated from the valve stem), and the convex portion engages the associated cam follower 118 and thereby holds the basket in its raised position. Cams 112 and 114 operate in coordinated fashion such that, at this point in the cycle, the lobe of cam 112 is oriented away from the valve stem and thereby allows the valve to be lifted and thus closed by the basket. Conversely, in FIGS. 9 and 10 , the concave part of cam 114 is above the camshaft axis and the lobe of cam 112 is oriented toward the valve stem, whereby cam follower 118 —and thus basket 116 —is in its lowest position and the valve is open.
[0045] While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only preferred embodiments have been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. | A desmodromic valve system which provides direct bidirectional displacement of a valve stem of an internal combustion engine without the aid of a rocker arm, utilizing a semirigid basket operating in conjunction with a plurality of cams for each valve. The basket is disposed about the camshaft of the engine and secured to the valve stem by an integral retainer on a bottom portion of the basket, and is constrained to motion along the valve stem axis. The basket has a pair of downwardly oriented cam followers in the upper portion thereof, spaced apart from the valve stem axis. A central cam and a parallel pair of side cams are fixedly mounted on the camshaft so as to rotate therewith, the cams substantially surrounded by the basket and cooperating therewith to provide reciprocating valve action with positive bidirectional drive. The central cam is aligned with the valve stem axis, and the side cams are spaced apart from the valve stem axis, parallel to the central cam and respectively aligned with the cam followers. During a first part of a valve cycle, the central cam pushes the valve stem down so as to positively open the associated valve, and the valve stem pulls said basket down with it via the retainer. During a second part of the valve cycle, the side cams push the basket up via their respective cam followers and thereby cause the basket to pull the valve stem so as to positively close the valve. | 5 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of PCT application number PCT/EP2008/007292 filed Sep. 5, 2008, which designated the United States.
FIELD OF THE INVENTION
[0002] The invention relates to a package, consisting of a water-soluble foil with integrated functional depot, which is dimensioned in a way to hold a pre-defined amount of laundry and features at least one second compartment to contain the amount of washing agent required for the intended washing process as well as manufacture and utilization of this package with functional depot.
BACKGROUND OF THE INVENTION
[0003] Modern washing machines—especially those in the upper and top price segment—are able to determine the amount of laundry filled into the machine, and with the built-in electronics, programmed with the water hardness at the respective geographic location, are able to calculate the amount of washing agent needed, considering the selected washing program. However, washing machines which such options are found rather seldom in everyday life, which leads to the tendency to use more washing agent than actually needed, in order to gain especially good washing results, which leads to increased costs while resulting in a higher strain for sewage plants and increased strain for the environment. Based on European standards, the potable water in Germany is classified according to three water hardness categories: soft, medium and hard. Since modern washing agents, based on tensides, are less sensitive to the water hardness, caused by the salts of earth alkali metals, and are already equipped with (phosphate-free) water softeners, the amount of washing agent, required for class 1 water hardness, (soft) is usually sufficient. Only if washing temperatures above 60° C. are required, the additional use of a phosphate-free water softener is recommended. In most cases, a special “pre-washing” of the laundry is abdicable—if pre-washing takes place, it is carried out with the “hot wash” in the temperature range of 60° C. or above—a “pre washing” is carried out with cold water and is used to help removing stains caused by proteins or blood. Laundry can be categorized into “wool laundry”, “fine laundry”, “white laundry”, “colored laundry” and “laundry for high washing temperatures”. “Fine laundry” and “colored laundry” are usually washed with water temperatures of 30° C. or 40° C., while “laundry for hot wash” is washed at 90° C.—however, experience shows that such laundry can also be washed with good results at 60° C., which considerably saves energy. In general, the use of a mild detergent for “delicates” and “colored laundry” and a premium detergent for “hot wash” is usually sufficient. Dirty clothes made of wool usually represent only a fraction of the laundry of an average household and are usually washed with special detergents. Mostly, sensitive clothes made of wool are hand-washed.
[0004] Laundry bags of different designs, that are washed together with the laundry in a washing process, are well known. In order to allow the washing liquid to intrude into the laundry easily, netted bags, made of cord are used. Their disadvantage is that the hard knots of the mesh may damage sensitive fabrics, and on the other hand these knots are stressed mechanically by the washing process, which considerably limits the lifetime of those netlike materials. This has led to the search for laundry bags made of weaved fabrics. Such fabrics needed to be highly durable while not becoming too heavy after having absorbed water. At the same time, the material should not be too porous, in order to effectively eliminate any accumulation and consecutive reproduction of microorganisms within the fabric. Since such laundry bags require rather high production costs, they needed to be re-usable and needed to be designed in a way to withstand the temperatures of tumble dryers, since melting plastic materials would have destroyed the laundry irreparably. As a conclusion, it can be stated that there are several conflicting goals already known from the prior art, influencing the development of a successful problem solution to get a container for collecting and sorting laundry of different types, which is easy to handle, while allowing production at low costs.
[0005] DD 001161 U describes a laundry bag made of a cotton or polyamide fabric that features a hollow hem with a cord used to seal the bag. Although this “spin-dryer washing bag” does not impose any strain on the laundry it contains, it needs to be opened manually prior to the washing procedure in order to empty its contents into the washing machine. It also needs to be washed together with the laundry. In case the bag is washed while containing the laundry, excessive imbalance during the drying and spinning process might result.
[0006] DE 17 44 019 U describes a laundry bag made of a Polyester fabric, which avoids the disadvantage of cotton fabrics, but does not overcome the disadvantage of the problem solution already known from DD 001161 U.
[0007] DE 94 21 043 U describes a laundry bag which opens itself inside the washing machine, consisting of an especially folded fabric, which opens up during the first phases of the washing process. This laundry bag is re-usable—but it needs to be washed together with the laundry and also needs to be dried and folded after each washing cycle, before it can be used again. At least, this problem solution offers the advantage that no unauthorized persons can get into contact with dirty or even infectiously contaminated laundry while opening the laundry bag.
[0008] DE 89 03 043 U therefore describes a laundry bag which automatically opens itself inside the washing machine, which is made of a material with waterproof coating on the inside in order to allow safe transport of infectiously contaminated laundry as it is found especially in clinical applications whereby it is ensured that clinical personnel do not get in direct contact with the laundry during transport or while filling the washing machine.
[0009] DE 90 16 622 U proposes a folded “dosing bag” for a washing agent in the form of a powder, which consists of a water permeable fabric, which can hold a defined amount of washing agent and opens itself at the beginning of the washing process. This “dosing bag” is also re-usable.
[0010] The patent literature knows a number of water-soluble packages which are used for example to hold hazardous substances, such as pesticides, herbicides and the like and are intended to provide single-service package for agricultural use. They are simply inserted into a specified amount of water in order to gain the correct dosage for spraying. Such packages are described e.g. in WO-A 97/27743 and EP-B 0 347 221. They usually consist of a foil made of polyvinyl alcohol. The water solubility of this material can be influenced and controlled by respective additives and special manufacturing processes, such as mono-axial or bi-axial stretching during the extrusion process.
[0011] EP-A 0 700 989 describes a packaged cleaning agent for dishwashers wrapped into a foil made of polyvinyl alcohol which wraps around the cleaning agent until the beginning of the main cleaning process of the dishwasher.
[0012] GB-A 2,305,931 describes a water-soluble detergent container, consisting of two halves, which are connected to each other and contain a washing powder or dish washing detergent. This specification does not contain any information as to the material used.
[0013] FR-A 2 601 930 describes a water-soluble bag containing some type of substance, preferably a pharmaceutical substance. GB-A 2,090,603 refers to a water-soluble foil made of a combination of partly hydrolyzed polyvinyl acetate and polyacrylic acid.
[0014] EP-B 0 556 781 describes a water-soluble thermoplastic foil material, consisting of a copolymer made of N-vinyl acetamide and another suitable vinyl monomer, such as vinyl acetate or vinyl butyrate.
[0015] DE-A 101 40 597 reveals the use of cross-linked polyvinyl alcohols derived for example by processing polyvinyl alcohol with dimethyl tartrate, for the production of synthetic granules used for the production of water soluble foils. By skilful selection of the ester components, the water solubility of the foils can be variegated. The specification also includes synthetic granules which allow the production of foils, which only swell up and soften in water without dissolving completely.
[0016] The prior art includes several suggestions as to the requirements suitable for a water soluble package for washing agents, dish detergents or compositions for agrochemical use, and how the solubility of such a packages can be variegated in a time-controlled manner—additionally there are suggestions as to the characteristics of laundry bags designed for the temporary storage of laundry, which allow pre-selected feeding of the washing machine, preferably without anyone needing to open such a bag prior to filling its contents into the washing machine. In this connection, however, it is disadvantageous that the package itself remains in the washing machine, which means added weight and reduces the “usable net weight” of the laundry to be washed, and which requires subsequent drying and manual preparing of the packages prior to any repeated use. In case the package contained contaminated materials, there is also the need for disinfection.
SUMMARY OF THE INVENTION
[0017] Therefore the object of the invention was to provide a water-soluble package, consisting of one first and at least one second compartment, which are strictly separated from each other. The first compartment serves to hold laundry, the second compartment serves to contain the required amount of washing agents needed for the intended washing procedure, additional compartments, if so, may contain e.g. disinfectants, in case the soluble package is to be used for infectiously contaminated laundry from hospitals, or they may also be used for additional washing additives, such as phosphate-free water softeners, bleaching agents, stain removers or similar products, where the separation of such additives is especially important if it is desired or even required to prevent any contact between these substances prior to the washing process. Such additives should preferably be available in water-free form, such as powder, granulate or in compressed form. However, it would also be an advantage, if washing agents and additives can also be used in the form of fluids, pastes or gels. The size of the first, second and where applicable any additional compartment needs to be adjusted to the defined volumes. For example, the first compartment needs to hold a specified amount of dirty or contaminated laundry, such as 1-2 kg, 3 kg, 4-5 kg or 6 kg for household use, and the size of the second and where applicable any additional compartment needs to be adjusted accordingly, in order to hold the amount of washing agent or additives required for the intended washing process. For commercial use, the size of the first compartment needs to be bigger in order to hold for example 7.5 kg, 10 kg, 15 kg or 20 kg of dirty laundry. The second compartment needs to be adjusted to the amount of laundry in the first compartment. Besides that it is to be made certain that the walls of such a water-soluble package need to allow easy handling without the danger of tearing prior to the washing process. However, when inserted into the washing liquid, it is necessary for the laundry to absorb the liquid as soon as possible, wherefore the water-soluble package shall open within the liquid as fast as possible, which might be supported either by means of perforations or rated break points. The foils selected to design a water-soluble package need to dissolve completely and residuelessly during the washing process, and any residues left in the water need to be biodegradable without causing any excessive strain for sewage plants.
[0018] Since foils with different characteristics as to their ability to dissolve in water are well-known—some of them dissolve only at temperatures above 50° C.—it was another object of this invention to provide a package for hot wash, holding washing agents for two different washing programs. Principally, this type of laundry is first pre-washed in cold water, in order to dissolve stains caused by blood or substances with a high protein content, the main wash cycle then is carried out at elevated temperatures, preferably above 60° C. The washing agent for pre-washing therefore should be inserted into the second compartment, along with the washing agent for the main wash cycle—in an additional water-soluble package, which then can be seen as a further compartment, spatially separated from the first compartment, which only may dissolve in water at a temperature above 50° C. The dissolving at this also shall occur within a few minutes.
[0019] For the field of clinical laundry it was another object of this invention, to provide a package, which allows the safe storage of especially stained or infectiously contaminated laundry, which means a package according to the required security procedures, for laundry, stained with substances, such as blood, protein containing substances, wound secretions, and sputum, as well as bacterially infected laundry, since laundry like this needs to be disinfected and washed without getting into contact with employees during the process of storage, transportation or filling the washing machine.
[0020] Work clothes used in smelly areas, as they are common in agriculture, poultry breeding, chemical industries, e.g. when handling mercaptanes or synthetic or other odorous substances, pharmaceutical industries and the like can be a real bother if they are stored temporarily in a package according to this invention until the package is filled completely. Therefore here a problem solution is required, which allows repeated opening and closing of the package according to the invention, until it is filled optimally and ready for washing, to avoid strong odor or at least noticeably reduce it.
[0021] The foil material to be used should preferably be of thermoplastic nature and allow easy hot-sealing or gluing with a suitable adhesive which will also dissolve in the washing liquid without leaving residues. The material should also be easy to supply, in order to allow marketing of such a package at competitive prices. It should be possible to distribute such laundry bags in the form of shipping cartons containing multiple units. Finally it was the object of the invention, to provide a suitable foil-material for a water-soluble package in a way that the water-soluble package, already containing further product in it's original state in the second compartment for later use, can be folded or convolved anywise spatially minimized in a highly compact form, for cost effective storage and transport of the package. Of course, the individual layers of the foils of such a water-soluble package must remain intact during the storage at the point of sale or at the consumer's home, without sticking to each other or becoming brittle.
[0022] Packages as described above are ideal as “collectors” for laundry and suitable for private households, as well as small businesses, such as restaurants, bars, bistros, medical practices etc., since such package can be made available with a defined volume—such as 1-2 kg, 3, kg, 4-5 kg, 6 kg—matching the optimum filling volume of a typical household washing machine or matching the “energy saving” programs of such machines, which is especially suitable for a “single household”.
[0023] For commercial applications, the desired package can be designed more voluminous, e.g. with a maximal capacity such as 7.5 kg, 10 kg, 15 kg or 20 kg, to match the larger capacity of commercial washing machines—made from a sturdier while still easily water-soluble wrapping material with an adequate larger supply of washing agent. By using multiple packages of this type side by side, it is possible to pre-sort the laundry in order to simplify the later washing process with the required washing programs.
[0024] Since the provided water-soluble package is to be used for separation and sorting of laundry in private households, it was a further object of the invention to re-enforce the edges of the water-soluble package alongside the upper end of the first storage compartment in a way to allow hanging the package into a suitable stand without being damaged, overstretched or torn by the weight of the accumulating laundry. As several versions of the water-soluble package shall be provided, the foil must be printable in a well-known and common way to indicate the intended use to the consumer, such as “wool”, “delicates”, “linen”, “colored laundry”, “hot wash” etc. and to indicate the maximum capacity of the respective unit. The business company, distributing such a package, also needs to be able to apply the legally required product information, as well as sales promotional statements. Naturally, any imprints on the foil must not stain the laundry during the washing process.
[0025] In order to reduce the overall weight of the package, the walls of the first compartment are repeatedly stamped out with a suitable cutter, to create what is in the broadest sense a net-like structure. Needless to say that applying such openings can also be achieved in any other way known by any person skilled in the art. The space between all elements of this net-like structure—meaning the size of the openings—must be selected in the way to be sized smaller than the smallest piece of laundry, for which the package is intended, such as a crumbled up handkerchief or a sock for children. If the invented package shall be used, for example, for the laundry of a hotel, these openings can have a larger dimension, provided the required stability and tear-resistance of the package according to the invention are not compromised. The residues of the foil when the net-like structure is punched out can be recycled for production of new foils.
[0026] The punching is done in a way that despite lower weight, a widely tear proof package is provided. It is particularly favorable, if the foil is not manufactured in a uniform thickness but with structures of increased thickness in longitudinal direction in the sense of “bearing and supporting elements”. Naturally, the number of this structure or these structural elements is dependent on the weight of the laundry the package is intended to hold.
[0027] The subsequent punching of the net-like structures described above, needs to be carried out in a way that the function of the reinforcing structures of the package according to the invention is not interfered with by this processing. According to the German Patent Application DE 10 2007 042 450.9 the first compartment needs to be designed in a way to hold 1-2 kg, 3 kg, 3-5 kg or 6 kg of dirty (or if so also contaminated) laundry for the domestic range or 7.5 kg, 10 kg, 15 kg or 20 kg of dirty (or if so also contaminated) laundry for commercial sector.
[0028] The maximum size of the punched-out holes and the remaining “ligaments” in-between and finally the nature of this net-like structure can be easily determined by tear-resistance tests. The resulting tear-resistance should be at least 50% higher than the respective maximum total weight of a fully filled package would require.
[0029] The punched-out holes can be of any shape, such as round, oval, rectangular, square, trapezoid, rhombical or in an irregular form. It is solely of importance that punching or positioning of holes saves at least 50%, preferred at least 70% and especially preferred at least 80% the previous weight of the plastic material of the package according to the invention, thereby reducing the amount of foil, to be dissolved in the washing liquid.
[0030] Instead of using a foil with structures of increased thickness in longitudinal direction in the sense of “bearing and supporting elements”, it is also possible to add such “bearing and supporting elements” subsequently on an already processed foil by applying strips of foils made of water soluble material. This can be done by either ultrasonic sealing, or by moistening the strips to cause a sticking effect, or by bonding it with a suitable bonding agent. In principle it is also possible to apply strips of foil to the bag to form “bearing and supporting elements”, prior to punching the required holes. These “bearing and supporting elements” only serve to guarantee the stability and bearing capacity of the package according to the invention, after the weight of the foil was reduced from punching holes that followed, in order to reduce its weight to the extend possible. These “bearing and supporting elements” need to run from the lower seal of the package all the way to the doubled-up hem at its top opening. To achieve its function, it is insubstantial, whether the supportive strips are mainly applied horizontally between these two points or run diagonally or in form of any possible curve.
[0031] Another embodiment of the package uses a section of a tubular foil of any suitable geometry, which is then filled with the washing agent required for the watching process, as well as any other required additives, which thereafter is sealed in order to form the “second compartment”, and then is applied onto the package in a way to provide a “bearing and supporting element” as aforesaid. The required amount of washing agent and other additives, if required, is derived from the intended package-size and accordingly from the maximal storage capacity of the first compartment holding the laundry, whereby then the dimensions of the required tubular foil as to its length and diameter can be achieved simply. Preferably, the required section of the tubular foil is approximately of the same length as the package measured from its lower seal to its folded upper hem. As already described hereinbefore, it is insubstantial, whether the sections of foil filled with washing substances are applied mainly vertically between upper and lower end of the package according to the invention, or diagonally or at any curved line possible.
[0032] In a further embodiment, a tubular foil is manufactured in the known manner and, when positioned plain, furnished with the aforesaid punched-out holes. The resulting net-like structure is then cut in the desired sections and finished to the package according to the invention. At this it is advantageous to punch-out the holes intermittently, in order to be able to cut the resulting tubular foil in these areas, which remain unpunched to close the walls of these sections permanently, e.g. by hot-sealing or ultrasonic sealing, to provide the desired water-soluble package with functional depot.
[0033] At this point, the prime idea behind the invention needs to be emphasized: It is essential to provide a package, able to hold a specified amount of laundry, which then is reserving an appropriate amount of washing agents, additives and other substances needed. In case the package is made of a material with punched-out openings, the required amount of washing agents, additives and other substances if needed, will need to be filled in a suitable separate package, which also consists of water-soluble material and which is tightly sealed to form the second compartment which is joint to the first compartment holding the laundry. It remains considerably important that these inserted amounts of substances cannot be removed from the water-soluble package with functional depot without visibly damaging or destroying it.
[0034] In another embodiment, from a water-soluble plastic material as described in detail in DE 10 2007 042 450.9, an endless filament or an endless strip-like tape is manufactured, which is subsequently woven by a well-established weaving method to a net-like plain or tube-like fabric, from which water-soluble package with functional depot, according to the invention, is produced by the aforesaid manner. When indicated, the knot-like sections of this fabric can be subjected to a short thermal treatment, in order to strengthen it and to get it inherently stable. Also in this way a water-soluble package with functional depot can be produced, with a second compartment to hold the required amount of washing agents, additives and other substances, if needed, contained in a suitable separate package, which is also made of water-soluble material. This second compartment is sealed as described above. For this solution as well, the tensile strength of the filament or tape, as well as the tensile strength of the resulting fabric will need to be tested in a simple and suitable way.
[0035] Besides the lower net weight of the water-soluble package according to the invention with functional depot, it is particularly advantageous that the provided laundry will be soaked with water very fast, which considerably increases its weight and causes the surrounding packaging material to tear open much faster in order to release the laundry.
[0036] The material used for the package according to the invention preferably dissolves completely while being already in contact with cold water. The washing agents, additives and other substances stored in the second compartment may also be packed in separate bags made of different types of foil, so that the washing agent, intended for pre-washing or a disinfectant are packed in a foil, already dissolving in cold water, since pre-washing is done with cold water, while the washing agent intended for the main wash cycle is packed with a foil completely dissolving in water only at temperature levels above 40° C. In this way, two different washing procedures can be successfully performed consecutively.
[0037] That object is attained by selecting synthetic granules, available in the trade, a processable material for forming thermoplastic foils is selected, which can be processed into tube-like foils by means of standard production technologies. In order to ameliorate its mechanic characteristics, this material may be stretched mono-axially or bi-axially during the extrusion process. The synthetic granules may be selected from a mixture of polyvinyl acetate and polyacrylic acid or polyvinyl alcohol or partially hydrolyzed polyvinyl alcohol or a copolymer made of N-vinyl acetamide and vinyl acetate or a copolymer of N-vinyl acetamide and vinyl butyrate or methyl hydroxypropyl cellulose or a polycondensate from polyvinyl alcohol and dimethyl tartrate or a polycondensate from polyvinyl alcohol, citric acid and phthalic acid anhydride or similar granulates for the production of water-soluble foils, which are freely available in the trade. In general it is also possible to use so-called “biopolymers” derived from renewable raw materials by chemical processes. Such “biopolymers” for the production of water-soluble foils, as well as all other plastics stated—polymers, copolymers, polycondensates and their mixtures—are well known to the persons skilled in the art. By the reaction of polyvinyl alcohol with a mixture of maleic acid anhydride and phthalic acid anhydride in a polycondensation, it is possible to produce synthetic granules suitable for foils which only soften at increased water temperatures or are only partially soluble. By using such foils, it is possible to produce small bags containing washing agents in the form of fluids, pastes or gels which are inserted into a the second compartment of the package according to the invention, spatially separated from the first compartment. These small bags will only dissolve in the main wash cycle, when getting in contact with the hot washing liquid, then releasing their content. The release of this washing agent will be promoted by the rotating movement of the drum of the washing machine, as well as the motion of the laundry itself. It might be necessary to remove residues of such small bags and dispose of them manually.
[0038] Matching the requirements of small households, e.g. for singles or for “small washing” only in limited quantities, or for the use of the energy saving programs of washing machines, the packages according to the invention are manufactured in a way that the first compartment can hold only 1-2 kg or 3 kg of laundry. For general household use, the package according to the invention must be available with a capacity of 4-5 or 6 kg of laundry, which matches the maximum load capacity of the commercially available washing machines. The amount of washing agent and eventually needed additives in the second or any additional compartment shall be dimensioned in a way to be sufficient for the maximum laundry capacity of the package without causing any over-dosage. The amount of washing agent shall be adjusted to the new water hardness class 1 (soft) according to EU classification. Other proportions and dosages shall not be excluded—if manufacture and distribution of the package according to the invention primarily occurs in areas with hard or extra hard water, it is possible to adjust the dosage of the washing agent accordingly.
[0039] For industrial applications and commercial laundries, where dirty working clothes, tablecloths from restaurants etc. will be pre-sorted and washed later on, embodiments of packages according to the invention are made available with a capacity of more than 6 kg up to 20 kg. For this, embodiments of packages according to the invention are chosen that can hold 7.5 kg, 10 kg, 15 kg or 20 kg of laundry. The amount of washing agents and additives, contained in the spatially separated second compartment and if necessary additional compartments shall be adjusted accordingly. Naturally, it is also possible to provide packages according to the invention with capacities of more than 20 kg e.g. for commercial use—since the limiting factor for maximum capacity of the package according to the invention is only the capacity of the commercial washing machine—however, for safety at work, such heavy units requiring the use of special handling equipment, which actually suggests the use of smaller units with a maximum weight of 10 kg or 20 kg, which allow easy handling for the operational staff.
[0040] In order to increase the braking strength of the foil—especially when it comes to the production of packages according to the invention with increased capacity and a maximum load between 10 kg and 20 kg—it is favorable not only to use foils with higher strength, but to equip the foil with axial profiles of higher material thickness. For the production of water-soluble package according to the invention with functional depots, foils are used with a thickness between 25 and 100 μm—preferred with a thickness of 35-80 μm and especially preferred with a thickness of 45-55 μm. If the foils are produced with reinforcing, at least partially in axially direction orientated profiles, these foils will feature a material thickness of 45-150 μm—preferred with a thickness of 80-100 μm—in the area of such profiles. Naturally, the thickness of the foil needs to be adapted to the size of the package according to the invention to be made, as well as to the intended maximum laundry capacity.
[0041] Corresponding to the intended volume of the first compartment a commercially available tube-shaped water-soluble foil will be cut to the required length and processed to the package with a first and at least a second compartment. For this, there are several modes of proceeding, well-known to a person skilled in the art. For example, it is possible to hot-seal the film-tube alongside the cutting edge, when it is cut to length to fill the intended washing agent, which should preferably be available as a powder, a granulate or in the form of compacted spherical bodies, into the resulting bag-shaped compartment, which is hot-sealed a second time after inserting the washing agent, in a way that at least a second compartment is formed, spatially separated from the first compartment, to keep the washing agent and when indicated other additives securely separated from the laundry in the first compartment, in order to prevent any undesired mixing prior to the washing process. Filling the second compartment with washing agent may lead to adhesion of dust from residues of the washing agent along the desired hot-sealing position. Therefore ultrasonic hot-sealing of the tube is advantageous, especially, when washing agents are inserted, which incline to dust. However, a thermal sealing process by means of compressing the tubular foil between two heated profiles in an appropriate way is also possible. Both sealing processes for foils are well known to a person skilled in the art. Generally, it is also possible to use a water-soluble bonding agent to stick the tubular foil at the desired positions. It is quintessential for realizing the invention that the water-soluble package with a separate functional depot is formed with a first compartment, intended to hold the laundry, needs to remain open initially—differently, it could not serve its purpose—in order to allow filling it with laundry, whilst the second and if needed other compartments, however, needs to be securely sealed after filling with washing agent—which may be a mild detergent, an agent for colored laundry, an all-purpose detergent, or others like a washing agent for curtains, or bleaching agent, disinfectant or any other substance required for the washing procedure, so that their content at the desired time is released in course of the washing process completely.
[0042] Basically, it is not necessary to produce the package according to the invention by means of cutting sections of an endless tube-shaped foil. In fact, it is also possible to fold a plain sheet of a suitable water-soluble foil and form a tube-like bag by hot-sealing or sticking two of its edges. Quintessential for realizing the invention is only the secure separation of the first and the second compartment, as well as any additional compartments, as needed. In another embodiment, the second and if needed any other compartments may also be positioned at the side or parallel to the first compartment need not to be, spatially separated, below the first compartment. This geometric structure can also be achieved by durably closing a section of a tube-shaped foil at the lower end by hot-sealing, and by applying a second seal vertically to the first one and, after filling this second compartment with the intended material, it will be closed with another seal. In a further embodiment, when producing a bag as described before, orient it in a way that one of its corners points downward, fill the washing agent into this corner and apply a hot-seal to close this section of the bag above the filling level. This procedure also provides a package with a functional depot according to the invention, in which the first and the second, and if needed, any other compartment, are spatially separated. However, the preferred and easiest method seems to be the production of the water-soluble package according to the invention from an endless tube-shaped foil with respective hot-seals running crosswise to the transport direction of the tube. In principle, it is also possible to produce the functional depot separately as a shaped part, for example by producing it as a section of a smaller tube-shaped foil and closed on only one side, filling this bag later on with the intended material, closing it, and fixing it durably at a suitable area of a larger section of a tubular foil. However, this is more complex than the production of the package according to the invention from only one tubular foil, the embodiments as describes first are more cost-efficient, and therefore are preferred.
[0043] Prior to its use, the water-soluble package according to the invention with functional depot needs to be folded as compact as possible, to allow easy packing and cost-efficient transportation to the sales outlets. Therefore, the embodiment, having the second compartment at the opposite end to the first compartment is to be preferred. Although other embodiments shall not be excluded basically.
[0044] If the water-soluble package according to the invention with functional depot is to be used to collect laundry for subsequent hot-wash, a further embodiment is provided, which features two portions of washing agent within the second compartment. The first portion is filled directly into the second compartment and is used for pre-washing with cold water. The second portion of the washing agent is inserted inside a separate bag, made of a type of foil, which only dissolves at temperatures above 50° C., in order to activate this portion of the washing agent only in the main washing cycle at elevated temperature. Respective foils providing the required characteristics are generally known to the men skilled in the art. The second portion of the washing agent is also inserted in the second compartment after which it is sealed in a way described above. The separate bag in that the washing agent was inserted—at this, any further substance to be used for the intended washing sequence, which means any additive such as phosphate-free water softener, bleaching agent, stain removers, disinfectant etc. is hereafter described simply as “washing agent”, since it is stored separately from the first compartment.
[0045] If the water-soluble package according to the invention with functional depot is to be used in an average household or for “normally soiled laundry”, it would be very desirable that the laundry gets into immediate contact with the washing liquid, as soon as the washing procedure starts. This can be achieved by means of a tubular foil, which features at least one area of reduced material thickness, as this section will soak through quickly and therefore rip after getting into contact with the washing liquid, thereby acting in a certain way “as a rated break point”. But this bears the danger of unintentional ripping along the “rated break point” of the provided package under mechanical load, while filling the package with laundry or during transport. For this reason, it is an advantage to at least partially perforate the walls of the first compartment by applying slots, holes or stamped-out design elements, such as the logotype of the respective manufacturer. The punching-waste may be re-used for producing future foils or tube-like foils. In order to increase the mechanical stability of the provided package, the edges of the open side of the first compartment should be folded at least once and durably bonded to the residual foil of the package, on order to double the thickness of the material in this area. The foils used for the package according to the invention should be shaped in a way, to soften after getting in contact with the washing liquid at the latest within 5 minutes—preferably within at the latest 3 minutes—in order to release the laundry contained in the package. Within at the latest 30 minutes—preferably within at the latest 20 minutes—the residual foil needs to be fully dissolved. It must also be excluded that residues of the foil stick to the laundry. However, this should not represent any insurmountable difficulty to a person skilled in the art, since this type of foils is basically nothing new. New is the utilization of these foils according to the invention for the manufacture of water-soluble packages with integrated functional depot.
[0046] In order to allow easy separation of different types of laundry and to improve working procedures in home and commercial applications, the package according to the invention with functional depot can be inserted into suitable stands, keeping the package open, in order to facilitate filling the first compartment with laundry. In order to prevent any confusion, it is advantageous to print the intended use onto the package, such as “wool”, “delicates”, “linen”, “colored laundry” or “hot wash” or indicating the respective washing temperature, such as “30° C.”, “40° C.”, “60° C.” or “90° C.” by imprinting or marking. It is quintessential for the invention that the amount of washing agents or other additives matches the maximum capacity of the first compartment. As substantial information both for the private and the commercial domain, there needs to be also a statement indicating the maximum capacity of the package, such as 1-2 kg, 3 kg, 5 kg, 6 kg, 7.5 kg, 10 kg 15 kg or 20 kg. In addition, it is possible to print information about the manufacturer, such as brand or company logotypes in their respective colors onto the package. Such markings can also be applied by the user himself by using suitable implements, such as markers with water-soluble ink, which naturally must not affect the laundry during the washing process. Manufacturers of writing utensils know such inks, based on water-soluble colorants, which are decolorized by means of so-called “ink killers”, as the colorant used is transferred into the so-called “leukoform”, by means of the accordant reagent. Since most washing agents also contain bleaching agents, the use of such pens should not represent any problem for the intended work procedure.
[0047] If the water-soluble package according to the invention is used for clinical applications to collect infectiously contaminated laundry, another embodiment should be selected, in which the second compartment will contain a disinfectant, preferably in solid form, and in addition to a washing agent, packed in a package, made from a foil, dissolving only at an elevated temperature, such as 50° C. or above, which means that the additional compartment is spatially separated from the first compartment. Possible is also another embodiment with a “three-fold effect”. In this case, the disinfectant is filled directly into the second compartment, a first portion of the washing agent is contained in a separate bag made of a foil dissolving in cold water, which will release the washing agent after a delay of some minutes for the pre-wash, whilst the second portion of the washing agent, contained in a second bag, is only released at elevated temperatures, such as 50° C. or above for the main washing cycle. The package with integrated functional depot according to the invention made of water-soluble foils, provided for infectiously contaminated laundry of a hospital, is to be used within a special safety area, by especially trained personnel, closing each unit by means of a suitable clip or a cord made of polyamide or polyester, hermetically sealed and later on brought into the washing machine, without being opened by the staff, when loading it. This represents a vital safety aspect. In this application as well, the water-soluble package according to the invention will dissolve completely during the washing process—only the sealing-aid remains intact and can be reconditioned and reused after emptying the washing machine. Particularly favorable in this connection will be to provide the package according to the invention solution in combination with at least one pair of rugged one-way gloves, in a combipack as they are available for clinical applications or to distribute it in units containing at least two or even multiple of such product combinations in a collective package. The number of such product combinations contained in one collective package is determined by the conditions of the market to match the requirements of the customer group, which are to be targeted with this product idea.
[0048] Work clothes used in smelly areas, as they are common in agriculture, poultry breeding, chemical industries, e.g. when handling mercaptanes or synthetic or other odorous substances, pharmaceutical industries and the like, can be a real bother if they are stored temporarily in a package according to this invention until the package is filled maximally. In a particular embodiment for these applications it is advantageous, to double the upper edges of the package, to bond the border area at least partially to the residual foil durably, in order to form a hollow space, and to pull through a stronger tape, made of water-soluble foil, which will allow closing the package according to the invention temporarily and allowing repeated opening and closing, until it is optimally filled and ready for washing, to avoid strong odor trouble or at least noticeably reduce it.
[0049] Alternatively, it is possible to replace the tape made of water-soluble foil by a tape made of textiles or a conventional cord made of polyamide, polyester or any other suitable material, or to use a clip to close the compartment temporarily, and to remove such closing from the washing machine after the washing process, in order to be re-used.
BRIEF DESCRIPTION OF THE DRAWINGS
[0050] Further objects, features and advantages of the invention will be apparent from the following description of preferred embodiments thereof. These drawings are only exemplary and serve the purpose to demonstrate the object of the invention, without limiting it to a specific form or representing any final product characteristic. In particular, these drawings are not meant to determine any dimensions of the package. Individual components of the drawings are marked by reference numerals, which are further explained, in a subsequent descriptive text. In these drawings:
[0051] FIGS. 1( a )-( f ) show a method for making a package according to the invention;
[0052] FIGS. 2( a )-( d ) show alternate methods for making the package according to the invention;
[0053] FIG. 3 shows an application of the package in accordance with the invention;
[0054] FIGS. 4( a )-( d ) show an alternate method for making a package according to the invention;
[0055] FIGS. 5( a )-( d ) show a further alternate method for making a package according to the invention;
[0056] FIGS. 6( a )-( d ) show a still further alternate method for making a package according to the invention;
[0057] FIGS. 7( a )-( d ) show another alternate method for making a package according to the invention; and
[0058] FIGS. 8( a )-( f ) illustrate alternative features and methods for making same, in accordance with the invention.
DETAILED DESCRIPTION
[0059] FIG. 1 a shows a cut-off section 1 of the tubular foil made of water-soluble thermoplastic material, which in the first instance is open at both ends. FIG. 1 b shows the same tubular foil with one end closed by means of hot-sealing or bonding 2 , and is filled with washing agent or additives, as needed 3 through the opening 4 . FIG. 1 c shows a first embodiment of the package with functional depot according to the invention, where a hot-seal 5 or any other suitable form of closing means is positioned above the level of the washing agent 3 and horizontally to the transport direction of the tubular foil. FIG. 1 d shows the package with functional depot according to the invention in which, in a suitable way, e.g. with an imprint, indicating the type of laundry to be filled in and the respective washing temperature 6 , and where the walls are at least are partially furnished with slots, holes or figural perforations 7 . The hem alongside the opening 4 was doubled 8 up by folding the foil. Naturally, there are other options for reinforcing the hem, but these would mean increased efforts and therefore higher production costs. FIG. 1 e shows another embodiment of the package with functional depot, where one edge is directed downward, filled with washing agent 3 and where a hot-seal 5 ′ or any other suitable closing means is fixed above the level of the washing agent. FIG. 1 f shows another embodiment with a second compartment being attached on the inside or the outside of the first compartment, spatially separated from that second compartment. For this purpose a separate piece of foil can be initially attached partially, then the so formed “bag” is filled with the washing agent 3 and to be hot-sealed 5 ″ afterwards. In this embodiment it is also possible, filling the washing agent into a separate reservoir made of a section of a suitable water-soluble foil, which is then closed and attached by hot-sealing or any other suitable procedure. However, the embodiment of FIG. 1 f and described above, results in increased efforts and requires a higher amount of materials, which suggests to preferably use the embodiments described in the beginning.
[0060] FIG. 2 a shows a plain sheet made of a suitable water-soluble foil 21 which is folded in the middle 22 and hot-sealed on two sides in order to form the bag 20 as in FIG. 2 b . Hot-sealing can either be carried out along two (more or less) vertical and horizontal adjacent, initially open sides 23 , 23 ′, to meet then in a corner or along two parallel initially open sides. In either case, the result is a bag, which differs only as far as the position of the hot-sealed sides is concerned 25 , 25 ′.
[0061] FIG. 2 c finally shows two sheets of a foil 21 ′, 21 ″ which are positioned exactly above each other and are then interconnected along three sides 24 , 24 ′, 24 ″ in order to form a type of bag 20 ′ as is shown in FIG. 2 d , e.g. by hot-sealing, the bag then exhibiting three hot-seals 25 ″, 25 ′″, 25 ″″. The bags achieved in one of the ways described above form the basic element of a bag, which can be processed to the package with functional depot according to the invention. However, the procedural manners as aforesaid section require more work and material than the production of bags by cutting sections from a tubular foil—therefore the last-mentioned manufacturing procedure is to be preferred in practice.
[0062] FIG. 3 shows one of the possible utilizations of a number of the water-soluble packages according to the invention with functional depot, to pre-sort laundry into categories, such as delicates, colored laundry, hot-wash and white laundry to be washed at 40° C., such as white shirts. For this, a foldable stand 31 with a top plate 32 with at least two openings 34 , preferably four openings, such as shown in FIG. 3 . can be used, each opening fitted with a package according to the invention, optimally opened for easy filling and easy removal. Also possible is a wall-mounted support to hold at least one of the water-soluble packages with functional depot according to the invention. The design principle of such stands or supports is basically known, since similar solutions are already on the market and widely used—quintessential again the combination of such a stand or support with the package with functional depot according to the invention for pre-sorting and subsequent processing of laundry.
[0063] FIG. 4 a shows a truncated section 41 of the tubular foil made of water-soluble plastic material, which initially remains open at both ends. FIG. 4 b shows the same tubular foil with one end closed by appropriate means of hot-sealing or bonding 42 , the resulting compartment filled through the opening 44 with washing agent or additional additives, if needed 43 . FIG. 4 c shows a first embodiment of the package according to the invention with functional depot, where a hot-seal 45 or any other suitable form of sealing is positioned above the level of the washing agent 43 and across the machine direction. FIG. 4 d shows the package according to the invention with functional depot, where subsequently openings 46 were applied to the walls in a suitable manner, e.g. by punching, above the sealing 45 . The hem alongside the opening 44 was doubled up by folding the foil in order to gain a hemstitch 47 , in which e.g. a tape made of a likewise water-soluble material for closing the package can be drawn.
[0064] FIG. 5 a shows a truncated section 41 of the tubular foil made of water-soluble plastic material, which initially remains open at both ends. FIG. 5 b shows the very same tubular foil with punched-out openings 46 . FIG. 5 c shows the tubular foil closed on one side by hot-sealing or by bonding, in which the washing agent 43 or a required additive is contained in a bag 48 made of water-soluble foil. After inserting the bag 48 , the lower partition of the package is closed by hot-sealing or bonding along the seam 45 , as shown in FIG. 5 d.
[0065] FIG. 6 a shows a truncated section 41 of the tubular foil with “bearing and supporting elements” 49 , made of a water-soluble plastic material, applied longitudinally in order to partially increase the thickness of the foil, initially still open at both ends. FIG. 6 b shows the tubular foil, closed on one side along a seam 42 by hot-sealing or by bonding in a suitable manner, ready to be filled with the washing agent 43 or other additives, when required, through the opening 44 . FIG. 6 c shows the package closed by seam above the inserted amount of washing agent. Detail drawing D shows the “bearing and supporting elements” 49 , used to increase the foil thickness. FIG. 6 d shows the package according to the invention, ready for filling with laundry. The reference numbers result from FIG. 4 and FIG. 5 .
[0066] FIG. 7 a shows a truncated section 41 of the tubular foil, which is already closed at one end by a seam 42 . Depending on the required carrying capacity of the package, a certain number of strips 410 , made of water-soluble foil, are applied to the exterior of this foil section. Naturally, applying these strips can also been done before sealing the tube section at one end. If the tube section is turned inside out before closing it at one end, the strips of foil are at the interior of the package, avoiding ridges at the exterior. As shown in FIG. 7 b , this tube section is now filled with the required washing agent 43 and other additives if needed, and hermetically sealed along the seam 45 , as shown in FIG. 7 c . FIG. 7 d shows the invented package according to the invention with a number of openings 46 punched into the open part of the bag, which is intended to hold the laundry afterwards, whereas this preferably should be done in a way that the strips of foil 46 either remain intact or are only punched out partially, in order to prevent limiting the stabilizing function accomplished by applying those strips.
[0067] FIG. 8 a shows a truncated section 41 of the tubular foil with a number of openings 46 , as shown in FIG. 8 b intended to reduce the overall weight of the package according to the invention. FIG. 8 c shows the same punched tubular foil after being closed at one end by a seam 42 . FIG. 8 d shows truncated sections of a tubular foil with much smaller diameter 41 ′, which are closed at one end 42 ′ by a seam. Subsequently these truncated sections 41 ′ are filled with the required washing agent 43 and other additives, if needed, and followed by tightly sealing at the other end by means of a second seam 42 ″. After filling, these sections of tubular foil are providing the reservoir of washing agent 48 ′, whereas the length of this reservoir corresponds to the length of the truncated tubular foil, as shown in FIG. 8 c , reaching from the seam at one end to the doubled up hem 47 at the other end, which will be applied in a later production stage.
[0068] At least two of these reservoirs with washing agent 48 ′ are applied to the truncated tubular foil shown in FIG. 8 c , which is closed at one end. The dimension of the reservoir with washing agent 48 ′ and the number of reservoirs needed depend on the calculated amount of laundry the package according to the invention with functional depot is intended for afterwards. | A water-soluble package, having a water-soluble foil defining a first compartment and at least one second compartment separate from the first compartment, wherein the at least one second compartment contains a functional depot. | 3 |
FIELD OF THE TECHNOLOGY
The present invention relates to an ink cartridge for an ink jet printer.
BACKGROUND
The ink cartridges of conventional ink jet printers are all provided with a negative pressure mechanism which can generate negative pressure inside the ink cartridge. However, negative pressure is generated from the beginning when the ink cartridge is used for printing and is constantly maintained until the ink is used up. As a result, when the ink cartridge is under the state of negative pressure for a long time, the ink of a printing head can be easily sucked out to damage the printing head and further affect printing quality.
Another kind of ink jet printer adopts the design of non-shaft-type ink supply. A replaceable ink cartridge of such an ink jet printer is positioned below a printing head. The ink is pumped by a suction pump into an irreplaceable ink cartridge above the printing head, which is connected with a nozzle, and the ink is maintained by a negative pressure mechanism. The replaceable ink cartridge of such an ink jet printer only plays a role of accommodating the ink. However, this replaceable ink cartridge is a constant pressure structure, the quantity of ink is detected by a buoy inside the replaceable ink cartridge, and the buoy, due to its own weight, is incapable to detect the quantity of ink accurately when the quantity of ink is small. Therefore, the following function is configured in the program of the printer: when a sheltering part on the other side of the buoy can no longer be detected, the printer prompts the depletion of the ink after printing another 2-3 ML of ink according to an internal counting device.
Based on this function of the printer, a replaceable ink cartridge with an ink bag (as shown in FIG. 1 ) has been invented for use with such printer. Such an ink cartridge has no air-conducting passage so as not to contact with the air. However, since the demand of detecting the depletion of the ink of the printer needs to be met, the ink bag of the ink cartridge is divided into two parts with one being used cooperatively for detection and the other one being used for accommodating the ink, and the two parts communicate with each other. In order to meet the demand of installation detection of the ink cartridge, the ink bag for detection is sealed by a silica gel film. Due to the different sealing materials of the two parts of the ink bag, which are seldom completely identical to each other in density, toughness and the like, the reflection for suction force is difficult to control, thereby often resulting in that the ink bag for accommodating the ink firstly shrivels and the ink bag for detection then shrivels. In this case, the quantity of ink inside the ink cartridge is less than 2 ml when the detection component detects the depletion of the ink. As a result, the problems about insufficient supply of ink at printing port and burnout of the printing head are generated.
SUMMARY
The invention provides an ink cartridge for an ink jet printer, in order to solve the technical problem that constant negative pressure in the process of using the ink cartridge leads to the damage and deformation of the parts inside the ink cartridge which affects printing quality.
In order to solve the technical problem above, one aspect of the present invention provides an ink cartridge for an ink jet printer. The ink cartridge comprises a cartridge body and a detection mechanism for detecting the ink cartridge and the residual quantity of ink, wherein the cartridge body comprises an ink tank for storing ink, an ink outlet for supplying ink to a printing head of the printer and an air inlet, the ink tank comprises a first ink chamber and a second ink chamber, a first negative pressure mechanism is arranged between the first ink chamber and the second ink chamber, the ink cartridge is characterized in that a second negative pressure mechanism is further arranged between the first ink chamber and the second ink chamber, the first negative pressure mechanism and the second negative pressure mechanism cooperatively control the ink inside the first ink chamber to be consumed preferentially than the ink inside the second ink chamber, and the second negative pressure mechanism generates negative pressure only when a certain quantity of ink inside the ink tank is reached.
The first negative pressure mechanism may be a gravity valve and the second negative pressure mechanism may be a buoyancy valve.
The gravity valve comprises a gravity valve base and a gravity valve core with a density higher than that of the ink.
The buoyancy valve may comprise a buoyancy valve base and a buoyancy valve core with a density lower than that of the ink.
The detection mechanism for detecting the ink cartridge and the residual quantity of ink comprises a first detection component cooperative with a first sensor on the printer, a second detection component cooperative with a second sensor on the printer and a soft support cap communicating with the second ink chamber on the cartridge body, the second detection component comprises a movable rod member and a fixed shaft arranged at the cartridge body, the movable rod member is rotatably connected with the cartridge body through the fixed shaft, the soft support cap is positioned at a corresponding position where the movable rod member droops under gravity and comes into contact with the movable rod member when a position adjusting member of the movable rod member overtakes the soft support cap.
The front wall of the cartridge body, on which the ink outlet is arranged, is provided with an elastic component, one end of the elastic component is fixedly connected with a front wall of the cartridge body, the other end of the elastic component is capable of reach the wall of an accommodation space of the ink cartridge of the printer by bending the elastic component, the elastic component is provided with a support position, and the movable rod member is supported by the support position on the elastic component.
A negative pressure value under control of the gravity valve is larger than a collapsing resistance value of the soft support cap.
The support position is an opening formed on the elastic component.
The front wall of the cartridge body, on which the ink outlet is arranged, is provided with a clamping position, and one end of the elastic component is fixedly connected with the cartridge body through the clamping position.
According to the technical solution described above, as the ink tank is internally provided with a second negative pressure mechanism, the second negative pressure mechanism generates negative pressure when a certain quantity of ink inside the ink tank is used for printing, and negative pressure inside the ink tank is not generated until the used ink inside the ink tank reaches a certain quantity, i.e., negative pressure is generated only in case that the residual quantity of ink is small in the end, therefore the technical problem that constant negative pressure in the process of using the ink cartridge leads to the damage and deformation of the parts inside the ink cartridge which impact on printing quality can be avoided. In addition, more accurate control is achieved by adopting the soft support cap for warning about the residual quantity of ink, and the manufacturing technology is simple. Finally, since the space for buoy is saved, more ink can be accommodated, thereby saving printing cost of users.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a conventional ink cartridge which may generate printing defects.
FIG. 2 is a schematic diagram of the ink cartridge according to an embodiment of the invention.
FIG. 3 is a schematic diagram of the state of the ink cartridge at the beginning of installing the ink cartridge into the printer.
FIG. 4 is a schematic diagram of the state of the ink cartridge in case of sealing the buoyancy valve during printing.
FIG. 5 is a schematic diagram of the collapsing state of the soft support cap of the invention.
FIG. 6 is a schematic diagram of the state of the ink cartridge when the gravity valve is opened.
FIG. 7 is a schematic diagram of the cooperative ink cartridge housing.
FIG. 8 is a schematic diagram of the installation of the ink cartridge provided by the invention.
FIG. 9A is a schematic diagram of the buoyancy valve base and the gravity valve base inside the ink cartridge.
FIG. 9B is a sectional view of the buoyancy valve base and the gravity valve base inside the ink cartridge.
FIG. 9C is a schematic diagram of the soft support cap inside the ink cartridge.
FIG. 9D is a sectional view of the soft support cap inside the ink cartridge.
FIG. 10 is a schematic diagram of fluid flowing when the buoyancy valve base is opened and the gravity valve base is sealed.
FIG. 11 is a schematic diagram of fluid flowing when the buoyancy valve base is sealed and the gravity valve base is opened.
In the Figures: 1 Ink cartridge 2 air inlet 3 first detection component 4 elastic component 5 second detection component 6 soft support cap 7 ink outlet 8 buoyancy valve 9 gravity valve 10 ink cartridge housing 102 second sensor 104 first sensor 105 ink cartridge housing cap 61 flexible support film 62 communication passage 63 soft support cap sealing rib 81 buoyancy valve base 82 buoyancy valve core 811 valve core sealing portion 812 fluid passage 813 valve base sealing rib 91 gravity valve base 92 gravity valve core.
DETAILED DESCRIPTION
The ink cartridge for ink jet printer, as shown in FIG. 2 , comprises a cartridge body 1 and a detection mechanism for detecting the ink cartridge and the residual quantity of ink. The cartridge body comprises an ink tank for storing ink, an ink outlet 7 for supplying ink to a printing head of the printer and an air inlet 2 . The ink tank comprises a first ink chamber 20 and a second ink chamber 21 , a gravity valve 9 and a buoyancy valve 8 are arranged between the first ink chamber 20 and the second ink chamber 21 . The gravity valve 9 and the buoyancy valve 8 cooperatively control the ink inside the first ink chamber 20 to be used up preferentially than the ink inside the second ink chamber 21 . By means of the buoyancy valve 8 , a negative pressure is generated only when a certain quantity of ink inside the ink tank has been consumed for printing, and the air inlet 2 is arranged on the first ink chamber 20 .
The detection mechanism for detecting the ink cartridge and the residual quantity of ink comprises a first detection component 3 cooperative with a first sensor on the printer, a second detection component 5 cooperative with a second sensor on the printer, and a soft support cap 6 communicating with the second ink chamber and provided on the cartridge body. The second detection component comprises a movable rod member 5 and a fixed shaft arranged at the cartridge body, the movable rod member is rotatably connected with the cartridge body through the fixed shaft. The soft support cap 6 is positioned at a corresponding position where the movable rod member droops under gravity, and comes into contact with the movable rod member when a position adjusting member of the movable rod member overtakes the soft support cap. A front wall of the cartridge body, on which the ink outlet is arranged, is also provided with an elastic component 4 , one end of the elastic component 4 is fixedly connected with the front wall of the cartridge body, the other end of the elastic component 4 can contact a wall of an accommodation space of the ink cartridge by bending the elastic component 4 . The elastic component 4 is provided with a support position, and the movable rod member is supported by the support position on the elastic component 4 . The support position is an opening formed on the elastic component for receiving the removable rod member. The front wall of the cartridge body, on which the ink outlet is arranged, is provided with a clamping position, and one end of the elastic component is fixedly connected with the cartridge body through the clamping position.
The air outside the ink cartridge enters the cartridge body 1 through the air inlet. The ink outlet 7 plays a role of transferring the ink inside the ink cartridge 1 to the printing head of the printer.
The first detection component 3 performs the detection in cooperation with the first sensor 104 on the printer. After the ink cartridge is installed, the first detection component 3 blocks the light emitted from a light emitting portion of the first sensor 104 , as shown in FIG. 8 , so that a receiving portion of the first sensor 104 receives no light. After the detection in the printer in cooperation with the second detection component 5 , successful installation detection of the ink cartridge is achieved.
The second detection component 5 performs the detection in cooperation with the second sensor 102 on the printer. After the ink cartridge is installed, the second detection component 5 blocks the light emitted from a light emitting portion of the second sensor 102 , so that a receiving portion of the second sensor 102 receives no light. After the detection in the printer in cooperation with the first detection component 3 , successful installation detection of the ink cartridge is achieved, as shown in FIG. 8 .
The elastic component 4 plays a role in installation detection in cooperation with the second detection component. That is because the following states exist in the process of installing the ink cartridge into the printer:
In the beginning, two sensors 102 and 104 of the printer are under the state of switching-on. While the installation of the ink cartridge is performed, light is emitted from an emitting portion of the second sensor 102 and is blocked by the movable rod member 5 so as not to return to the receiving portion of the second sensor 102 . Under this state the light path of the second sensor 102 is switched off, while the first sensor 104 which is not in contact with the first detection component 3 is under the state of switching-on.
Light is then emitted from the emitting portion of the second sensor 102 , as the elastic component 4 comes into contact with the wall of the ink cartridge housing 10 , the elastic component 4 undergoes displacement so as not to support the movable rod member 5 any more, and thus the movable rod member 5 rotates around the fixed shaft, and a displacement of the movable rod member 5 relative to a front arm of the ink cartridge 1 along an installation direction is larger than a length of the second sensor 102 along an installation direction. In this case, the detection position of the movable rod member 5 has passed by the sensing position of the second sensor 102 , and the light is emitted to the receiving portion of the second sensor 102 . Under this state, the light path of the second sensor 102 is switched on, while the light emitted from the emitting portion of the first sensor 104 is blocked by the first detection component 3 , thus the light path of the first sensor 104 is under the state of switching-off.
As the ink cartridge is further pushed into the printer, light is emitted from the emitting portion of the second sensor 102 , and the movable rod member 5 comes into contact with and is supported by the soft support cap 6 at its rear part, as shown in FIG. 4 , and displacement of the movable rod member 5 stops, and now the movable rod member 5 is positioned at the detection position of the second sensor 102 . In this case, the light emitted from the second sensor 102 is blocked by the movable rod member 5 so as not to return to the receiving portion of the second sensor 102 . Under this state, the light path of the second sensor is switched off, and the light emitted from the emitting portion of the first sensor 104 is still blocked by the first detection component 3 . Therefore, the light path of the first sensor 104 is also under the state of switching-off, and the ink inlet of the printer is cooperative with the ink outlet 7 of the ink cartridge and smooth ink supply is achieved.
During the initial state in the above installation process, as shown in FIG. 3 , the elastic component 4 supports the movable rod member 5 . When the movable rod member 5 passes by the detection position of the second sensor 102 once, the elastic component 4 does not support the movable rod member 5 any more. Afterwards, the movable rod member 5 is supported by the soft support cap 6 . When the ink cartridge is removed from the printer, the elastic component 4 becomes to support the movable rod member 5 once again so that the movable rod member 5 returns to its original position so as to repeat the installation process above when reinstallation is required.
The elastic component 4 plays another role of springing the ink cartridge away from the ink cartridge housing 10 when the ink cartridge is removed from the printer. This process is as below: when the ink cartridge is installed into the ink cartridge housing 10 , as shown in FIG. 7 , the elastic component 4 is deformed, and the deformed elastic component 4 cannot reset after the ink cartridge housing cap 105 is closed, thus the elastic component 4 resets to push the ink cartridge away from the ink cartridge housing when the ink cartridge housing cap 105 is opened.
The soft support cap 6 plays a role of supporting the movable rod member 5 after the ink cartridge is installed, so that the second detection component 5 is maintained at the detection position of the second sensor 102 to achieve successful installation detection, as shown in FIG. 8 .
The soft support cap 6 , as shown in FIG. 9C , comprises: a flexible support film 61 , which can support the movable rod member 5 and can collapse according to internal pressure change; a communication passage 62 , which can be communicate with the ink chamber; and a soft support cap sealing rib 63 , which can seal the ink chamber, as shown in FIG. 9D .
The soft support cap plays another role of cooperating with the ink depletion detection of the printer, and the ink depletion detection comprises the following process:
The quantity of ink continuously decreases as the printing is performed. When the ink inside the ink cartridge is used up, the flexible support film 61 of the flexible support cap 6 , due to the adjustment of the buoyancy valve 8 and the gravity valve 9 inside the ink cartridge 1 , collapses under the suction action of an ink supply needle of the printer when the ink is about to be used up. The flexible support cap 61 no longer supports the movable rod member 5 and the movable rod member 5 continues to move under gravity to be away from the position where the light path of the second sensor 102 is blocked. Light is directly emitted to a light receiving element. In this case, the first sensor 104 of the printer is blocked, while the second sensor 102 is not blocked, thus the printer prompts the ink will be used up and sends a signal to the user.
The buoyancy valve 8 and the gravity valve 9 play the role of adjusting the pressure inside the ink cartridge, so that the soft support cap 6 is caused to collapse, as shown in FIG. 5 , so as to further achieve the purpose of detecting ink depletion.
The buoyancy valve 8 comprises: a buoyancy valve base 81 as shown in FIG. 9A and a buoyancy valve core 82 , wherein the buoyancy valve base 81 is characterized by a valve core sealing portion 811 cooperative with the buoyancy valve core 82 , a fluid passage 812 for communicating the ink chamber with the ink outlet, and a valve base sealing rib 813 capable of fixing the valve base 81 and sealing the periphery of the valve base 81 ; the valve core 82 is characterized by having a density lower than that of the ink and being capable of sealing the fluid passage 812 in cooperation with the valve base sealing portion 811 , as shown in FIG. 9B .
The gravity valve 9 comprises: a gravity valve base 91 and a gravity valve core 92 , wherein the gravity valve base 91 includes the same structural characteristics as the buoyancy valve base 81 ; the valve core 92 is characterized by having a density higher than that of the ink and being capable of sealing the fluid passage under certain pressure (>−3 KPa) in cooperation with the valve base sealing portion, as shown in FIG. 8 . A negative pressure value under the control of the gravity valve is larger than a collapsing resistance value of the soft support cap.
The process of controlling the buoyancy valve 8 and the gravity valve 9 is as follows:
When the ink inside the ink cartridge is not used up, the buoyancy valve core 82 of the buoyancy base 8 floats above the ink due to the density thereof lower than that of the ink. The buoyancy valve 8 is under the state of opening, and the pressure inside the ink cartridge is the same as outside pressure. The gravity valve core 92 of the gravity valve 9 , due to the density thereof higher than that of the ink, is cooperative with the valve base sealing portion so that the gravity valve is under the state of closing. The flowing path of the ink is shown as the dotted line in FIG. 10 .
The level of the ink continuously descends as the ink is used for printing. By the time the buoyancy valve core 82 is cooperative with the valve base sealing portion, the buoyancy valve 8 is closed. Since the gravity valve 9 is also under the state of closing, the cavity adjacent to the ink outlet is under the state of sealing. Since the ink supply needle of the printer has certain suction force, thus printing is not influenced.
After both the buoyancy valve 8 and the gravity valve 9 are closed, the pressure of the ink chamber communicating with the soft support cap 6 gradually decreases as the ink is used for printing. When the pressure reaches certain value (−0.5 to −3 KPa), the flexible support film 61 of the soft support cap 6 is deformed so as not to support the second detection component 5 any more. In this case, the printer prompts the ink is about to be used up (2-3 ml of the ink remains inside the ink cartridge at this stage).
After the situation that the ink is about to be used up is promoted, the ink supply needle of the printer still sucks the ink ceaselessly. When the pressure at the ink outlet reaches certain value (≦−3 KPa), the pressure generated by the pressure difference between atmosphere and interior of the cavity can overcome the gravity of the gravity valve core 92 of the gravity valve 9 , thus the gravity valve core 92 moves away from the sealing position and the gravity valve 9 is opened. The air can enter through the fluid passage, and the ink chamber is communicated with the soft support cap 6 , shown as FIG. 6 . In this case, the fluid flows in a manner as shown in FIG. 11 . When the pressure inside the cavity decreases, since the gravity valve 9 is opened, the pressure interior of the cavity is inclined to be identical with external pressure (because the pressure value is a negative value, the value decreases, e.g., the previous pressure value is −70 KP, while the present pressure value is −60 KP), the pressure generated by the pressure difference between atmosphere and interior of the cavity cannot overcome the gravity of the gravity valve core 92 of the gravity valve 9 , thus the gravity valve core 92 returns to the sealing position once again, and the gravity valve 9 is closed once again. As the ink is used, the gravity valve 9 is opened and closed ceaselessly to balance the pressure inside the cavity until the ink is used up.
This negative pressure control manner with a high control precision can achieve accurate control of the pressure when the soft support cap 6 collapses, thereby ensuring the accuracy of ink depletion detection of the printer. | The invention relates to an ink cartridge for an ink jet printer. The ink cartridge comprises a cartridge body and a detection mechanism for detecting the ink cartridge and residual quantity of ink, wherein the cartridge body comprises an ink tank for storing ink, an ink outlet for supplying ink to a printing head of the printer and an air inlet, the ink tank comprises a first ink chamber and a second ink chamber, a first negative pressure mechanism and a second negative pressure mechanism are arranged between the first ink chamber and the second cavity, the first negative pressure mechanism and the second negative pressure mechanism cooperatively control the ink inside the first ink chamber to be consumed preferentially than the ink inside the second ink chamber, and the second negative pressure mechanism generates negative pressure when a certain quantity of ink inside the ink tank is used for printing. Since negative pressure inside the ink tank is not generated until the used ink inside the ink tank reaches a certain quantity, i.e., negative pressure is generated only in case that the residual quantity of ink is small in the end, the technical problem that constant negative pressure in the process of using the ink cartridge leads to the damage and deformation of the parts inside the ink cartridge which impact on the quality of printing can be avoided. | 1 |
BACKGROUND OF THE INVENTION
This invention pertains to a bale forming machine of the type for making round bales. This type of machine picks up crop material such as hay or straw from windrows in a field by means of a pickup head on the machine and forms the picked up material into round bales by utilizing various mechanisms. Some of these machines produce round bales which have a relatively hard core and succeeding layers wrapped upon said core that are relatively uniform but not as dense as the core. This type of bale does not tend to sag when left in the fields but, if such bale is formed from relatively wet material, the core tends to rot after a period of time. In North America, because there is relatively little baled material which is of a very wet nature, baling machines which form round bales with hard cores have been popular. In certain sections of Europe, as well as other areas in the world, where the climate is much more moist than in North America, it has been found that if a round bale is formed with a soft core, it is possible to prevent rotting of the core. Bales formed with soft cores generally have more dense or harder outer layers or shells but such round bales tend to sag when left for any substantial amount of time in the field.
Typical examples of round baler machines developed heretofore for purposes of forming round bales with soft cores comprise the subject matter of prior U.S. Pat. No. 4,119,026, dated Oct. 10, 1978, in the name of Sacht, and U.S. Pat. No. 4,212,149, dated July 15, 1980, in the name of Krone et al. In the Sacht patent, a series of endless conveyor belts extend around sets of rollers or drums, the drums being mounted on transverse axes extending between opposite sides of the baler frame, the conveyor belts being arranged in a generally circular pattern with a space provided between two adjacent sets of conveyor belts to comprise an opening into which material is delivered by a pickup head. The conveyor belts move the material generally into a loose spiral and ultimately form a soft core around which somewhat more dense layers are wound until a bale of desired diameter is formed. Furnishing and maintaining the plurality of conveyor belts necessary in this machine results in considerable expense.
In the patent to Krone, a hollow cylindrical winding compartment is provided with a bottom gap through which the crop material is fed by a pick-up device into a substantially cylindrical boundary wall, the inner surface of the boundary wall is swept by an endless apron in the form of transverse slats spaced from each other with the ends thereof connected to endless chains which move in annular channels or guides to ensure that the inner portion of the apron will remain adjacent the inside of the cylindrical boundary wall, while the outer portion of the apron rides around the exterior of the cylindrical boundary wall. In general, the apron comprises a substantially C-shaped configuration, the ends of which are spaced to form the bottom gap referred to above and the apron also extends around a pair of spaced drive rollers or sprockets located adjacent the opposed ends of the C-shaped configuration.
Additional prior U.S. Pat. No. 4,434,607, dated Mar. 6, 1984, in the name of Campbell, is an example of a baling machine adapted to form round bales with hard cores. To prevent the machine from being overfilled, a trip lever and an actuating lever serve to interrupt the driving of the pickup header of the machine and thereby prevent structural damage to the machine.
The present invention is directed to a machine of the type to form round bales with relatively soft cores surrounded by layers of crop material becoming more dense toward the outer surface of the bale. The mechanism by which such bales are formed is simpler and less complex than similar mechanisms of other machines as described above.
SUMMARY OF THE INVENTION
It is among the principal objects of the present invention to provide a crop baling machine of the type for producing round bales in which a cylindrical bale forming compartment receives crop material from a pick-up head, the bale forming compartment being defined by an endless apron which extends around inner and outer sets of guide members arranged in concentric circular patterns, the endless apron being arranged in a substantially C-shaped configuration upon said sets of guide members with the ends of the configuration spaced sufficiently apart to comprise an inlet for crop material to be delivered into the bale forming compartment. The machine also includes drive sprockets positioned at one end of the C-shaped configuration of the apron adjacent the top of the inlet and takeup guide sprockets positioned at the other end of the C-shaped configuration of the apron adjacent the bottom of the inlet, the takeup guide sprockets normally holding the concentric portions of the apron taut but being yieldable to permit the inner portion of the apron to expand a limited amount against the action of the takeup guide sprockets when a bale of desired predetermined size has been formed.
Another object of the invention is to provide power means for said drive sprockets in the form of an output shaft adapted to be connected to remote power such as a tractor p.t.o., belt means interconnecting said output shaft to said pick-up head to drive it and disconnect means in the form of a belt-tightening roller engaging said belt means, coupled with means actuated by movement of said takeup guide sprockets to release said belt-tightening roller from tightening engagement with said belt means to stop operation of said pick-up head when a bale of desired size has been formed, thus constituting automatic means for preventing structural damage to the machine.
A further object of the invention is to provide mounting for said takeup guide sprockets for limited movement in said frame and also to provide compression spring means operable in a direction upon said takeup guide sprockets to render the apron taut but said compression spring permitting said takeup guide sprockets to move against the action of the spring when a formed bale of crop material expands the inner portion of the apron extending around the inner set of guide members, the movable takeup guide sprockets also being supported in a bearing housing positioned in guide means, said housing having an actuating member for said disconnect means referred to above.
Still another object of the invention is to provide said disconnect means in the form of a pivoted cam lever engaged by said actuating member when one of said takeup guide sprockets is moved as aforesaid upon the completion of formation of a roll bale of desired size, whereby said cam lever by means of linkage effecting movement of said belt-tightening roller to inoperative position and thereby stop operation of the pick-up head.
One further object of the invention is to render the frame bi-partite with a forward portion and a rearward tailgate pivotally connected to the forward portion in the upper region thereof, and hydraulic cylinder units connected at opposite sides of the frame between said tailgate and forward portion of said frame to lift said tailgate outward and upward to discharge position, said baling machine otherwise being operated solely by mechanical power means derived from an external source such as a p.t.o. of a tractor.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation of a round bale forming machine embodying the principles of the present invention.
FIG. 2 is a side elevation similar to FIG. 1 but also showing in schematic manner the drive sprockets and takeup guide sprockets engaging the apron of the machine, said view being simplified from that shown in FIG. 1 to better illustrate said machine.
FIG. 3 is a fragmentary vertical section taken on a line 3--3 of FIG. 1.
FIG. 4 is a fragmentary, enlarged sectional elevation showing still further details of the mounting of the takeup guide sprockets and the manner in which the disconnect mechanism functions to stop operation of the pick-up head.
FIG. 5 is another fragmentary side elevation showing additional details of the drive and disconnect mechanism and particularly showing one position for the actuating member of the disconnect mechanism in full lines and an alternate position shown in phantom in which the cam lever of the disconnect mechanism is also shown in disconnect position.
FIG. 6 is a vertical sectional view of fragmentary nature taken on the line 6--6 of FIG. 5 and showing the operative relationship of one of the takeup guide sprockets with respect to the disconnect mechanism and the drive for the pick-up head.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring particularly to FIGS. 1 and 2, it will be seen that the machine embodying the principles of the present invention includes a frame 10 composed of a plurality of integrally connected structural members such as channels and rectangular tubes, the frame also being bi-partite with a forward portion 12 and a rearward tailgate 14, said forward portion and tailgate meeting along a line 16 as clearly shown in FIGS. 1 and 2 and said tailgate 14 being pivotally connected to the forward portion 12 of frame 10 by pivot pins 17. Frame 10 also is mobile by means of a pair of large wheels 18 mounted upon axle 20. Axle 20 also pivotally supports a pickup head 22 which has wheels 24 to support the forward end of the pickup head above the field surface 26.
The pickup head 22 includes side plates spaced transversely apart which support a drive shaft 28 for the rotatable fingers 30. The shaft 28 is driven by a sheave 32 which is fixed to one end of shaft 28. Frame 10 also includes a forwardly and downwardly extending tongue 34, the forward end of which, not shown, is connectable to suitable power means such as a tractor, the tractor being provided with a p.t.o. which drives input shaft 36 shown in FIG. 2 which, in turn, drive bevel gears that drive the output shaft 38.
The various structural members of the forward frame portion 12 and tailgate 14 support a series of relatively narrow rollers 40 which comprise an outer set of guide members which are circumferentially spaced around an outer circular pattern, duplicate sets of said rollers respectively being disposed at opposite sides of the frame 10. While the term "rollers" is used to denote a general type of rotatable supportring member, they also may comprise idler sprocket gears. It also will be understood that the structural members comprising the forward portion 12 and tailgate 14 of frame 10 are disposed against the outer surfaces of sheet-like side plates 42, one of which is fragmentarily shown in FIG. 3 on the inner side of the structural members shown therein.
An inner set of guide members such as rollers 44 are disposed in a generally inner circular configuration or pattern and these rollers 44 are primarily supported upon the forward frame portion 12 by a disc member 46, which is outlined by a heavy line in FIG. 2 and by a phantom line in FIG. 1, the major portion of the member 46 actually comprising a disc but also having a forward and upward extension 48 as clearly shown in FIG. 2. The disc member 46 also is shown fragmentarily in FIG. 3 and said figure also shows the mounting of the inner set of rollers 44. It also is to be understood that FIG. 2 is substantially a vertical sectional view through the machine approximately at the center thereof and comprises an inner view of one side of the machine, whereby it will be seen that shafts 28 and 38 are in section.
Extending around the inner and outer sets of rollers 40 and 44 is an endless flexible apron 50 which is shown in phantom in FIG. 1 and outlined by a broken line in FIG. 2, the apron includes an outer portion 52 and an inner portion 54, said inner and outer portions preferably being concentric and respectively supported by the rollers 44 and 40 to form a substantially cylindrical bale-forming compartment 55 shown in FIGS. 1 and 2.
The apron 50 preferably is of conventional construction and comprises a pair of endless flexible chains 56 such as shown fragmentarily in FIGS. 4 and 5 and in section in FIG. 3, said chains respectively being disposed adjacent the opposite inner surfaces of the side plates 42 of the forward portion 12 and tailgate 14. Extending between said pair of chains are a series of evenly spaced rods 58, the ends of which are appropriately connected to said chains.
As shown in FIGS. 1 and 2, it will be seen that the inner and outer portions of the apron 50 define a C-shaped configuration which encloses the bale-forming compartment 55. At the ends of the C-shaped configuration, the apron 50 extends around drive sprockets 60 and takeup guide sprockets 62 respectively mounted adjacent opposite sides of the frame 10. The space 64 between said opposite ends of the C-shaped configuration comprises an inlet to the bale-forming compartment 55 through which material picked up by the pickup head 22 is delivered to said compartment 55. The pickup head 22 also includes a series of windguard tines 66 of conventional nature.
Drive sprockets 60 respectively are supported upon the opposite ends of a shaft 68 for engagement with the apron chains 56. One end of shaft 68 has a sheave 69, see FIGS. 1 and 5, connected thereto. Output shaft 38 also has a sheave 70 fixed thereto and a belt or chain 72 extends therearound to deliver power to sheave 69, shaft 68 the drive sprockets 60.
Referring particularly to FIG. 4, each takeup guide sprocket 62 is supported by a bearing housing 74 slideable within a pair of parallel guides 76. A compression spring 78 extends between a fixed stop 80 on tailgate 14 of the frame 10 and the bearing housing 74, the takeup guide sprockets 62 being mounted upon a transverse shaft 82 supported by the bearing housings 74. The springs 78 as can be fully appreciated, especially from FIGS. 1 and 2, operate to maintain the apron 50 taut but also permit the inner portion 54 of the apron 50 to expand at least a limited amount when a bale of desired size has been formed within the compartment 55, the yieldability of the takeup guide sprockets 62 permitting such expansion and when that occurs, the present invention provides means for automatically disconnecting the drive to the pickup head 22 and thus prevents structural damage to the machine, the disconnection of power to the pickup head being described as follows.
Still referring particularly to FIG. 4, but also to FIGS. 5 and 6, the fingers 30 of pickup head 22 are driven by sheave 32 fixed to shaft 28 and around which drive belt or chain 86 extends, the latter also extending around driven sheave 88 which is fixed to a drive sheave 90 as clearly shown in FIG. 6, said sheaves being freely rotatably upon stub shaft 91 as shown in FIG. 5 and 6. An endless drive belt or chain 92 extends around a second sheave 94 which is fixed to drive sheave 69 and said belt or chain 92 also extends around sheave 90. Belt or chain 92 is of such length that it can loosely extend around sheaves 90 and 94 and when in loose condition, drive of the pickup head 22 does not occur. To effect such driving, however, a belt-tightening roller 96, as shown in FIG. 5, is movable between full line tightening position and phantom slack position. Such movement is effected by the following mechanism.
Acutating member 98 is fixed to bearing housing 74 and a roller 100 is pivotally mounted upon the outer end thereof as shown in FIGS. 4-6. A bell crank composed of integrally connected arm 102 and cam lever 104 is pivotally supported upon a fixed pintle 106 attached to one of the side plates 42 as shown fragmentarily in FIG. 6. Another bell crank composed of the short link 108 rigidly connected to a spring-biased lever 110 which carries the belt-tightening roller 96 is supported for limited pivotal movement by another fixed pintle 112 supported by side plate 42 as shown in FIG. 4. Extending between the short link 108 and arm 102 is another link 114, the opposite ends of which are freely pivotally connected thereto.
The operation of the disconnect mechanism for the pickup head 22 is as follows. When a bale of predetermined size has been formed within the compartment 55, the inner portion 54 of the apron 50 expands a limited amount for example, to the size shown in FIG. 2 as represented by the broken line, said inner portion 54 of the apron 50 then being disengaged from the inner set of rollers 44. When such expansion occurs, it causes the takeup guide sprockets 62 to move, for example, from the phantom position shown in FIG. 2 to the full line position or, as shown in FIG. 5, the extent of movement of the sprockets 62 is represented by the phantom position of the shaft 82 which also causes actuating member 98 and roller 100 to move from the full line positions to the phantom positions. The roller 100 is disposed within a notch 116 in cam lever 104 and such movement of the roller 100 causes clockwise rotation of the cam lever 104 on pintle 106 and this effects movement of the interconnected bell cranks and link 114 as illustrated in phantom and thereby moves the belt-tightening roller 96 from the full line tightening position to the phantom slack position, thus disconnecting the power from sheave 90 and thus stopping movement of the rotatable fingers 30 of the pickup head 22. As is readily apparent, such disconnection of power is effected automatically when the size of the bale formed within the compartment 55 is that which is desired and for which the mechanism has been set.
When a bale of desired size has been formed and, for example, the operation of the pickup head 22 has been stopped, it will be seen that the present invention also includes hydraulic units 118, the opposite ends of which respectively are connected to the forward portion 12 of the frame and the tailgate 14 as clearly shown in FIGS. 1 and 2. The hydraulic units 118 are operated preferably by control means, not shown, mounted on the tractor, for example, and connected by suitable flexible conduits, not shown, between a pump on the tractor and the units 118. Under such circumstances, only relatively low hydraulic force is required to effect such elevation of the tailgate 14 to conventional discharge position, not shown in the drawings. Appropriate control mechanism, also of conventional nature and not illustrated, is used to control the operation of the units 118.
The bale-forming machine described above also contemplates the use of signal mechanism either of visual or audible nature to notify the operator of the tractor, for example, that a bale of desired size has been formed within the compartment 55. Referring particularly to FIGS. 1 and 4, one example of signal means is illustrated which, for example, is of a visual nature and comprises a lever 120 pivotally mounted intermediately of its ends upon a pintle 122 supported by the tailgate 14. A visual signal indicator 124 is fixed to one end of the lever 120 at a location substantially farther from the pintle 122 than the opposite end 126 of the lever 120 to which one end of a tension spring 128 is connected and the opposite end of spring 128 is connected to a fixed member 130 attached to the tailgate 14. A visual signal indicator 124 is fixed to one end of the lever 120 at a location substantially farther from the pintle 122 than the opposite end 126 of the lever 120 to which one end of a tension spring 128 is connected and the opposite end of spring 128 is connected to a fixed member 130 attached to the tailgate 14. An elongated flexible member 132 such as a cable or cord, is connected to the lever 120 adjacent pintle 122 in opposition to the end 126 of the lever 120 to which the spring 128 is connected, the connection of the member 132 preferably including another tension spring 134. Flexible member 132 extends aound an idler pulley 134 which also is fixed to the tailgate 14 and includes a portion which extends, for example, to the bearing housing 74 to which it is connected by a pin or bolt 136. From the foregoing, it will be seen that as the size of the bale reaches a desired maximum limit and at least limited expansion of the inner portion 54 of the apron 50 occurs so as to move the bearing housing 74 to the right as viewed in FIG. 4, against the action of spring 78, the flexible member 132 will move in a direction to permit the spring 128 to pivot the lever 120 to the phantom, signaling position shown in FIG. 4, whereupon when the operator sees the latter position, he will stop operation of the machine and/or the pickup head 22, as desired, and open the tailgate 14 to effect discharge of the finished bale. Under such circumstances, it is not necessary to utilize the mechanism described above for automatically disconnecting the operation of the pickup head 22 of the bale-forming machine, if desired.
The foregoing description illustrates preferred embodiments of the invention. However, concepts employed may, based upon such description, be employed in other embodiments without departing from the scope of the invention. Accordingly, the following claims are intended to protect the invention broadly, as well as in the specific forms shown herein. | A crop baling machine of the type for producing round bales and in which a cylindrical bale forming compartment receives crop material from a pickup device, the bale-forming compartment being defined by an endless apron which extends around inner and outer sets of guide rollers. The endless apron also extends respectively around drive sprockets and takeup guide sprockets which are spaced apart to provide an inlet to the bale forming compartment, the takeup guide sprockets being mounted for limited movement against springs to maintain the apron taut but also permit limited expansion of the inner portion of the apron which extends around the inner set of guide rollers when the bale forming compartment is filled to a desired degree, and the movement of the takeup guide sprockets causing additional mechanism to disconnect the pickup device from the power source which drives it and thereby automatically prevent structural damage to the machine. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to a method of producing potassium permanganate from manganese dioxide ore and removing impurities from potassium manganate produced from the manganese bearing ore and which manganate is a precursor to permanganate in the production of potassium permanganate. In particular, the invention involves the electrolytic production of permanganate from manganate where the cathode and anode of the electrolytic cell are separated by a cationic membrane which is permeable to monovalent cations and which is substantially impermeable to anions. This separation creates a catholytic region for the production and separation of potassium hydroxide from the anolytic solution and permits a return of potassium hydroxide to the upstream portion of the process directed to the treatment of the manganese dioxide ore and impure precursor manganate.
The manufacture of potassium permanganate (KMnO 4 ) from manganese dioxide (MnO 2 ) containing ore requires at least three steps which require considerable amounts of potassium hydroxide. The first of these steps involves the production of potassium manganate VI (K 2 MnO 4 ) and may also involve the production of an intermediate potassium manganate V (K 3 MnO 4 ) from the manganese dioxide ore. A second step which requires considerable amounts of aqueous potassium hydroxide is the leaching of the manganate from insoluble ore impurities to obtain a leach solution of manganate. Yet another step which requires aqueous potassium hydroxide as a solvent, is the electrolytic oxidation of the potassium manganate to potassium permanganate. The first and third of these steps are generally represented by the following reactions:
(1) MnO.sub.2 +2KOH+1/2O.sub.2 →K.sub.2 MnO.sub.4 +H.sub.2 O
(2) K.sub.2 MnO.sub.4 +H.sub.2 O-electrolysis→KMnO.sub.4 +KOH+1/2H.sub.2
The step represented by equation 1 is a high temperature oxidation with air or other oxygen-containing gas to provide an ore oxidation product and is carried out in the presence of relatively concentrated potassium hydroxide solution, such as about 65% to about 90%. A number of methods are known for this oxidation step. It is known to roast a particulate mixture of manganese dioxide ore and potassium hydroxide. The mixture is roasted with air at about 225° C. while intermittently spraying water on the particulate mixture of solids. Another more preferable method is to add the particulate ore to a highly concentrated potassium hydroxide melt and introducing oxygen at elevated temperatures. This oxidation is described in U.S. Pat. Nos. 2,940,821, 2,940,822 and 2,940,823 which patents are fully incorporated by reference as if fully rewritten herein.
After the initial conversion of manganese dioxide to crude potassium manganate which also contains insoluble solids from the ore, the impure potassium manganate is dissolved or leached from the ore oxidation product with dilute aqueous solution of potassium hydroxide to form a manganate leach solution. Again potassium hydroxide is a necessary element in the purification of the manganate and ultimate production of the permanganate.
Equation 2 represents the electrolytic production of permanganate [Fin(VII)] from manganate [Mn(VI)]. While the electrolytic production of permanganate from manganate has been known for a long time, that electrolysis involves a number of known desired main reactions and also side reactions at the cathode and anode where the side reactions at minimum have to be controlled for the economic production of permanganate. The reaction in the electrolytic cell include:
At the anode
Main reaction: MnO 4 2- -e→MnO 4 -
Side reaction: 2OH - -2e→H 2 O+1/2O 2
At the cathode
Main reaction: H 2 O+e→1/2H 2 +OH -
Side reaction: MnO 4 - +e→MnO 4 2-
Side reaction: MnO 4 2- +e→MnO 4 3- which partly hydrolyzes to MnO 2 .
In prior electrolytic processes for the production of potassium permanganate, potassium permanganate is obtained in the form of crystals from a concentrated aqueous mother liquor. That aqueous mother liquor is a saturated solution of potassium permanganate which also contains relatively large amount of potassium hydroxide as well as alkali soluble impurities. These impurities are predominately potassium carbonate as well as lesser amounts of potassium silicates, aluminates, phosphates, etc. Prior art processes recognized the need for recirculation and conservation of potassium hydroxide used throughout the process of making potassium permanganate.
It is known that in the industrial production of potassium permanganate that only about 40% of the potassium hydroxide in the process streams is actually used to form the end product potassium permanganate. The remaining 60% of the potassium hydroxide is carried through the process in an aqueous solution as a reaction medium. The reuse of this large excess of potassium hydroxide is an important economic factor in the production of potassium permanganate.
As described in U.S. Pat. No. 3,172,830 to Carus, which is incorporated by reference as if fully rewritten herein, the potassium or alkali impurities in the aqueous mother liquor resulting after crystallization of the permanganate from the electrolytic cell can be causticized into potassium hydroxide using Ca(OH) 2 or CaO by the reaction K 2 CO 3 +Ca(OH) 2 →2KOH+CaCO 3 . This "causticization" conserves potassium hydroxide for reuse in the process such as in the leaching step. At least part of the mother liquor is concentrated to conserve potassium hydroxide for use in the initial oxidation of the manganese dioxide ore. That evaporation is energy intensive.
It is an object of the invention to provide for an improved process for the production of potassium permanganate from manganese dioxide containing ore, particularly as a continuous process.
It is another object of the invention to conserve manganese dioxide ore, electricity and potassium hydroxide in the electrolytic production of potassium permanganate.
It is yet another object of the invention to provide for a process for the production of potassium permanganate from manganese dioxide containing ore using potassium hydroxide to produce a manganate intermediate; and further to purify the manganate intermediate prior to electrolysis where potassium hydroxide (1) is made and collected in a catholytic region of an electrolytic cell and (2) is returned for use in the production of the manganate intermediate.
It is yet another object of the invention to use a cationic membrane not only to conserve raw materials in the electrolytic production of potassium permanganate, but also to minimize undesired side reactions in the electrolytic cell to increase the efficiency in the production of permanganate.
Yet another object of the invention is to inhibit the dangerous and potentially explosive mixing of oxygen and hydrogen gases which may be produced during the electrolysis process.
These and other objects of the invention will be recognized after review of the following description and summary of the invention.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow sheet illustrating the process.
FIG. 2 is a side view of the electrolytic cell illustrating a catholytic and anolytic regions.
FIG. 3 is a top view illustrating the flow of the catholyte and anolyte through the cell.
SUMMARY OF THE INVENTION
According to the invention, manganese dioxide containing ore is oxidized with a potassium hydroxide feed solution and oxygen to obtain an impure manganate mixture which is a crude slurry of precipitated potassium manganate. That slurry contains impurities in solution and suspended solids. The impure solid potassium manganate, as part of the impure manganate mixture, is leached to provide a manganate leach solution. Ore impurities remain undissolved and the manganate is in solution. The solid impurities are separated from the manganate leach solution, such as by filtration or centrifugation. The leach solution, which includes potassium hydroxide as a solvent, is fed to an electrolysis solution to an electrolysis cell where the cathode and anode are separated by a cationic membrane. The presence of an effective amount of KOH is necessary to form a stable solution of K 2 MnO 4 .
The cationic membrane is permeable to cations and is generally impermeable to anions. During the electrolysis to convert manganate into permanganate, potassium hydroxide is made at the cathode in a catholytic region and the potassium hydroxide is concentrated in that region between the cathode and the cationic membrane. Manganate is converted to permanganate at the anode, the manganate, permanganate and other constituents in the leachate being isolated between the anode and the cationic membrane which is the anolyte region of the cell. The potassium hydroxide is withdrawn from the catholytic region of the cell and is eventually returned to the upstream portion of the process. The potassium hydroxide may be recycled to become part of the potassium hydroxide feed solution which is used to oxidize the manganese dioxide ore. Permanganate is generated in the anolyte region of the cell. In an important aspect of the invention, however, the permanganate from the anolytic region flows into a crystallizer where permanganate is crystallized and separated from impurities such as potassium sulfate, potassium chloride, metal ions, which metal ions include cobalt, nickel, copper, as well as silicates and aluminares which include zeolites.
In a particularly important aspect of the invention the potassium permanganate is continuously produced in a cell as generally described in U.S. Pat. Nos. 2,843,537; 2,908,620; and 3,062,734 which are incorporated by reference as if fully rewritten herein. The latter patents describe a "Carus" cell which is a continuous flow through electrolyzer. It has a rectangular bipolar electrode where the anode is an open monel electrode attached to the steel cathode by a series of conductive baffles. The cell may have up to about 100 electrodes which are mounted vertically.
The cationic membrane in the cell of this invention is in a plane generally parallel to the anode and cathode creating the catholytic and anolytic region as described herein.
By isolating the anolyte from the catholyte, the cationic membrane (1) permits the production and concentration of valuable potassium hydroxide in the catholyte and permits the return of that potassium hydroxide to the upstream portion of the process, (2) prohibits or at least substantially inhibits the movement of permanganate ions to the cathode to avoid conversion of permanganate to undesired manganate, (3) inhibits the potentially explosive mixing and contact of oxygen formed at the anode with hydrogen formed at the cathode, (4) permits the reduction of the distance between the cathode and the anode to permit the running of the process at reduced voltages, and hence, reduced power costs, and (5) permits an increased cathode area which results in lower overvoltages required to run the process, and (6) reduces undesirable side reactions in the anolyte region because the potassium hydroxide generated in the catholyte region is kept separate from the anode.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the flow diagram of FIG. 1, the overall process is substantially continuous and is readily adapted to automatic control. The first step of the process is represented by oxidation of a manganese oxide ore in a suitable reaction vessel 1 or series of vessels, preferably by a liquid phase oxidation carried out in a highly concentrated 65 to 90% (by weight) potassium hydroxide melt. Air or some other oxygen-containing gas is supplied for this oxidation, and both fresh and recycle KOH may be introduced and adjusted to the desired concentration. The K 2 MnO 4 reaction product precipitates and forms a crude solid slurry of potassium manganate which can be transferred to the separator 2 to recover the crude solid product containing potassium manganate.
At the high KOH concentrations employed in a liquid phase oxidation, the K 2 MnO 4 is relatively insoluble as are many impurities such as K 2 CO 3 and the like. Therefore, the K 2 MnO 4 product is not in pure form but contains those impurities in dilute KOH solutions which are "alkali-soluble," i.e. potassium carbonate and also such minor impurities as the silicates, aluminates and/or phosphates of potassium; and further such trace elements such as Cu, Pb, Ni and Co. In addition, there is normally present a lesser amount of practically insoluble impurities or by-products derived from a minor ore content of elements such as iron, calcium, magnesium, or barium. These insoluble materials are hereinafter referred to as "ore impurities."
With the liquid phase oxidation in vessel 1, it is usually necessary to separate the concentrated KOH solution from the solid product, and this solution may then be recycled to the liquid phase oxidation as indicated. Where the ore is roasted in an almost dry state, it will be understood that the resulting product is relatively dry and usually does not require such additional treatment.
The impure K 2 MnO 4 product is combined with the leachate in which the manganate and impurities such as potassium carbonate are dissolved or leached from the ore impurities while the ore impurities remain undissolved. This step is carried out in a suitable mixing tank 3 by addition of a diluted and causticized mother liquor from heated vessel 11. Potassium hydroxide from the catholytic region of electrolysis cell 7 also may be used in this step, if desired. The mother liquor and/or potassium hydroxide employed for leaching is discussed more fully below, but with reference to the leaching step, the potassium hydroxide solution is prepared to provide 30-120 grams per liter, and likely 60-100 grams per liter of KOH after leaching. The crude K 2 MnO 4 product is added to this mother liquor and/or KOH solution in order to obtain a K 2 MnO 4 concentration of about 100-200 grams per liter. Leaching of the crude K 2 MnO 4 can be carried out at a temperature of about 45°-95° C.
The leach solution is conducted from vessel 3 by means of a suitable pump 4 into a separator (such as a filter) or a series of separators 5 for removal of all solid impurities including those which are produced during causticization of the mother liquor. If a single separator is employed, the leach filtrate solution containing the dissolved K 2 MnO 4 should be collected separately from wash water in order to provide better control over the concentration of dissolved substances. Separate filtrates can also be easily obtained by employing a series of two or more separators in a conventional manner. The filtrate from separator 5 as leach solution is conducted to mixing tank 6 in which the concentration of the various ingredients can be accurately adjusted for optimum results during electrolysis. The solids from filter 5 are washed and discarded, and the wash water is preferably recovered for use in causticization. The solid impurities from separator 5 consist primarily of CaCO 3 , excess Ca(OH) 2 and the insoluble ore impurities. Substantially all of the other alkali insoluble impurities, e.g. calcium silicates, are also removed at this point.
In mixing tank 6, the leach solution is preferably diluted with at least a portion of the mother liquor ML-I and precipitated salts can also be added from an evaporator 12. If necessary, additional water can be added at this point. However, additional quantities of water are desirably kept to a minimum in order to avoid excessive evaporation costs. The mixing in tank 6, to provide an electrolysis solution, should be carried out such that the resulting solution has a KOH concentration of about 80-190 grams per liter, and a K 2 MnO 4 concentration of about 10-50 grams per liter. The amount of KMnO 4 in this solution is kept as low as possible, preferably less than 20 grams per liter. Likewise, the amount of alkali soluble impurities such as K 2 CO 2 should be reduced to a minimum to avoid poor yields during electrolysis and an impure product.
The electrolysis solution from mixing tank 6 then is pumped into the electrolytic cell 7 for oxidation of K 2 MnO 4 into KMnO 4 at a temperature of about 55° C. Since the crystallization is usually carried out at temperatures somewhat lower than the electrolytic oxidation, it is generally advisable to provide some means for heating tank 6, for example by indirect heat exchange or by introducing live steam into the mixture.
The construction and operation of a known electrolysis cell 7 are described in detail in U.S. Pat. No. 2,843,537, No. 2,908,620 and 3,062,734. It is important to avoid precipitation or crystallization of potassium permanganate or impurities within the cell itself since this would cause a rapid decrease in the capacity and efficiency of the cell. In this respect, such undesirable precipitation will increase with increasing amounts of alkali-insoluble impurities present within the cell so that the throughput during electrolytic oxidation is strongly influenced by the manner in which impurities are removed from the overall process.
An expanded simplified view of an electrolytic cell having a continuous electrolytic flow is shown in FIG. 3. The cell has a bipolar electrode with an open monel anode 20 attached to a steel cathode 24. The interconnections are gasketed to prevent migration of solution from one region to the other. A cationic membrane 32 extends between and separates the anode and the cathode and creates an anolyte region 34 and catholyte region 36.
A cationic membrane with adequate chemical and mechanical integrity to withstand the conditions of the cell may be used. The cationic membrane may be a perfluorinated membrane, and in an important aspect, a perfluorosulfonate membrane which is based upon a copolymer of tetrafluoroethylene and a perfluorovinyl ether containing a terminal sulfonyl group. In a very important aspect, the latter polymer is cast on an inert cloth such as polytetrafluoroethylene, which is commonly sold under the mark Teflon, which a trademark of Dupont Chemical Company. Membranes which may be used in the invention are commercially sold under the mark Nafion by Dupont Chemical Company. Generally, reinforcement of these membranes, as previously described, is necessary due to the fragility of the membranes, the nature of the process, and the highly oxidative nature of the chemicals in the process. The thickness of the reinforced membranes is in the range of from about 0.1 to about 1 mm. The membrane is permeable to monovalent cations and is substantially impermeable to anions. In this connection substantially impermeable means >80% permselectivity in 0.5 to 0.6N NaCl. The membrane separates the cathode and anode which are separated by a distance in the range of from about 0.250" to about 0.300" with the membrane being about one half way between the cathode and the anode.
Cationic membranes can swell considerably. The membrane should be pretreated to ensure that it will not be loose in the cell frame between the electrodes. Swelling is influenced by temperature and time of immersion, the cation form of membrane and caustic concentration in the electrolyte. Membrane expansion occurs as temperature increases. Immersion of the membrane in an aqueous solution for 30 minutes is usually adequate to complete expansion, but this length of time is dependent upon membrane type and ions in solution. NE 450 and N 417 are sold with H + cation, but NE 430 is sold with K + cation. The H + membranes are pretreated by immersion in a boiling, aqueous solution of NaOH or KOH. These membranes shrink when they are converted from the H + form to the K + or Na + form. Finally, membrane shrinkage increases as the caustic concentration increases in the electrolyte.
The cathode current density is in the range of 500 to about 1500 A/M 2 assuming a flat electrode. The voltage across the cell is determined by the current density and cell resistance. For each cell it is in the range of from about 2.0 to about 3.5.
Because the membrane is permeable to monovalent cations, potassium cations K + go through the membrane toward the cathode and potassium hydroxide is made and collected in the catholyte region of the cell. The concentration of potassium hydroxide in the catholyte region will be in the range of from about 15 to about 35 weight percent, preferably toward the higher end. Because the membrane is substantially impermeable to anions, the membrane will collect and concentrate permanganate in the anolyte region and discourage the reduction of permanganate to manganate at the cathode. The membrane also causes the separation of hydrogen made at the catholyte from the oxygen made in the anolyte and reduces the amount of impurities recirculated in the system as compared to the prior art processes when the potassium hydroxide created is mixed with the mother liquor.
The product solution from the anolyte region of the electrolytic cell 7 is fed into a crystallizer 8 for cooling and crystallization of KMnO 4 product. A slurry of the crystalline product in the mother liquor can be continuously removed from the crystallizer and passed through a centrifuge 9 or similar means for filtering or separating the crystals while returning mother liquor (ML flitrate) to the crystallizer. The crystals are then dried in dryer 10 to obtain the KMnO 4 product.
The crystallizer 8 is also preferably constructed and operated as disclosed in U.S. Pat. Nos. 2,843,537 and No. 2,908,620, wherein the hot solution from cell 7 is first led into a gas separator and then pumped upwardly through a riser connected to the crystallization vessel. Cooling of the hot product solution produces a state of supersaturation of the KMnO 4 in the solution which is then released as KMnO 4 crystals. Nuclei or small crystals of KMnO 4 are always present in the main body of mother liquor in the crystallizer, upon which nuclei further crystal formation can take place. Larger crystals will settle to the bottom of the crystallizer for removal as a slurry while recycle mother liquor can be withdrawn near the top or surface of the liquid in the crystallizer. The mother liquor in the crystallizer is cooled to a temperature of about 50° to 30° C.
The mother liquor being withdrawn from the crystallizer as a recycle stream will vary in its composition within certain limits, depending upon a number of different factors including the proportions of reactants introduced into the electrolytic cell, the efficiency of the cell itself, the potassium hydroxide concentration and temperature of the solution, the amount of alkali-insoluble impurities which are permitted to accumulate and the amount of KMnO 4 which is effectively crystallized and separated from the mother liquor. Of course, it is desirable to separate and recover as much of the potassium permanganate as possible from the crystallizer, but as a practical consideration it is impossible and not necessarily desirable to completely free the mother liquor of potassium permanganate. Thus, it is advantageous to recycle small amounts of KMnO 4 to various stages of the process, e.g. as an aid in preventing hydrolysis of K 2 MnO 4 . Primary consideration is therefore given to operation of the crystallizer so as to obtain a maximum recovery of potassium permanganate without precipitating any other solids, including impurities, thereby avoiding complicated or extensive steps for purifying the separated product. In other words, purification of the potassium permanganate is substantially complete after crystallizing and centrifuging this product from the mother liquor.
In the normal operation of the electrolytic oxidation of the crude K 2 MnO 4 which has been leached into a potassium hydroxide solution, and in accordance with this invention, the mother liquor withdrawn from the crystallizer for recycle purposes may have approximately the following composition:
______________________________________ Concentration, grams per liter Broad Likely Range Range______________________________________KOH 100-200 125-175K.sub.2 MnO.sub.4 10-65 10-25KMnO.sub.4 10-30 15-20Soluble impurities 30-40 45-75______________________________________
It should be recognized, of course, that these values of concentration are taken after an approximate equilibrium has been reached during continuous operation. The amounts of KOH, K 2 MnO 4 and KMnO 4 are relatively stable and essentially determined by the efficient operation of the cell and crystallizer whereas there may be a greater fluctuation in the amount of alkali-soluble impurities, such as potassium carbonate and the potassium silicates, aluminates and phosphates, etc. because of the quantity of the manganese oxide ore being introduced into the process. The KOH concentration in the mother liquor is reduced compared to the known prior art processes by virtue of making and concentration of KOH in the catholyte.
The recycled mother liquor is preferably separated into three streams, one portion ML-I being recycled from the crystallizer 8 directly to the mixing tank 6 for adjustment of the aqueous mixture just prior to electrolysis. A second portion of the mother liquor ML-II may be recycled for causticization in vessel 11 and employed for leaching in vessel 3 as discussed more fully below. The third portion of the mother liquor ML-III is recycled to an evaporator 12 where sufficient water is taken off in order to precipitate the so-called "evaporator salts" in conventional manner. These precipitated salts may be returned to the causticizing tank 11 directly or after being redissolved. Any resulting concentrated KOH solution which was not produced and separated in the electrolysis cell can then be reused in the process, preferably by recycle to the first stage oxidation of the manganese oxide ore where it can be temporarily stored in any suitable vessel 13 or for use in the leaching of the manganate in the leaching vessel 3.
It will be recognized that by splitting the recycle mother liquor into three separate recycle streams, there is a high degree of flexibility in operating the overall process under optimum conditions. More importantly, the level of impurities in the system can be carefully regulated by causticizing the second stream ML-II such that alkali-soluble impurities are converted into potassium hydroxide. The proportions into which the mother liquor is separated into three recycle streams is best determined during actual operation of the process based upon a continuous analysis of the impurity level and the KOH concentration for leaching. It is desirable to reduce the amount of mother liquor recycled to the evaporator 12 to a minimum in order to avoid excessive evaporation costs.
The operation of the recycle system can be such that all of the mother liquor from crystallizer 8 is first recycled without any treatment, as represented by ML-I, to the mixing tank 6 until the impurity level reaches a maximum permissible value. The causticizing stream ML-II and/or the evaporation stream ML-III can then be operated intermittently to the extent that the impurity level must again be reduced and to the extent that the use of KOH produced in the catholytic region of the cell may be used in the leaching and the causticization process. Alternatively, it is preferred to carry out the entire process continuously under equilibrium conditions so as to maintain a relatively even level of impurities within prescribed limits and to continuously replenish the supply of concentrated KOH solution from the cell free of impurities. This alternative procedure permits a more accurate control of the process and avoids difficulties in adjusting the solution concentration for electrolysis. When operating under such equilibrium conditions, the recycle mother liquor is advantageously proportioned into the three separate streams about as follows:
______________________________________ Percent by volume______________________________________ML-I (direct recycle 85%ML-II (causticizing recycle 5%ML-III (evaporating recycle) 10%______________________________________
The product solution from the catholytic region of the cell has a potassium hydroxide concentration of from about 20 to about 35%, which is at least about 20% higher than in prior art continuous processes. The use of the recycle stream of KOH from the anolyte region of the cell and its subsequent reintroduction into the process as a leaching medium and KOH feed solution are essential improvements of this invention and are carried out in the following manner.
The KOH created in the catholyte is further concentrated with a combination of recycled anolyte or independently in the evaporator system. The resulting concentrated KOH is transferred to the oxidizer 1. | A method of producing potassium permanganate in an electrolytic cell is described where the cell is separated into a catholyte and anolyte region, potassium hydroxide is made in the catholyte region and is recycled back into upstream portions of the process to oxidize permanganate dioxide bearing ore. | 2 |
BACKGROUND OF THE INVENTION
Furniture should be functional, relatively easy to assemble and aesthetically pleasing. These requirements are sometimes in conflict. Furthermore, the ever changing nature of modern furniture materials also has an impact on these requirements. For example, transparent or translucent materials, such as glass, should also have the capability of being cleaned and this may require removal of the glass from the table.
Furniture manufactures are continuously seeking new methods of assembling their furniture, as well as reducing labor and material costs attributable thereto. The prior art discloses a number of mechanisms for attaching the legs of a table to the table top. For example, it is conventional to weld the legs to the metal rim of a table, to screw or bolt the legs directly to the table top and to connect the legs in a manner which causes the connection to be hidden. None of these various mechanisms, on the other hand, is particularly well suited for the rapid and secure attachment of a metal leg to a glass topped table.
In view of the above, those skilled in the art will appreciate that there is a need for an apparatus and method which permits the legs of a glass topped table to be securely attached thereto in a manner which permits the table to be rapidly assembled, the top to be cleaned and the table to be sturdy. The disclosed invention is just such an apparatus and method and one that can be manufactured from extruded aluminum or plastic parts, and one merely requiring the use of a screwdriver for assembly and disassembly of the table.
OBJECTS AND SUMMARY OF THE INVENTION
The primary object of the disclosed invention is an apparatus and method for rapidly and securely attaching the legs of a table to the table top.
An assembly for securing a leg of a table or the like comprises table top means including first and second spaced flange means. Clip means are provided for being secured to a leg and include first means engageable with the first flange means and second means comprising first and second juxtaposed hingedly connected leg members, one of the leg members engageable with the second flange means. Means are provided for forcing the members apart so that the first means is forced securely against the first flange means and the one member is forced securely against the second flange means.
The method of securing a leg to a table top or the like comprises the steps of providing a table top assembly including a top and a rim. The rim has first and second spaced flanges and a section extending therebetween and the top bears upon the underside of the first flange. A leg is provided and has clip means at one end thereof. The clip means includes first means for bearing against the top and second means comprising first and second juxtaposed hingedly connected members. The clip means is positioned between the flanges so that the first means bears against the table top and one of the members engages the second flange. The members are then forced and maintained apart so that the first means causes the top to be secured against the first flange and the one member is secured to the second flange.
These and other objects and advantages of the invention will be readily apparent in view of the following description and drawings of the above described invention.
DESCRIPTION OF THE DRAWINGS
The above and other objects and advantages and novel features of the present invention will become apparent from the following detailed description of the preferred embodiment of the invention illustrated in the accompanying drawings, wherein:
FIG. 1 is a perspective view with portions broken away illustrating a table assembled through use of invention;
FIG. 2 an exploded fragmentary assembly drawing of the invention;
FIG. 3 is a perspective view of the clip of the invention;
FlG. 4 is a fragmentary perspective view, partially in section, illustrating the clip of the invention positioned within the rim of the table; and,
FIG. 5 is a fragmentary cross-sectional view taken along the section 5--5 of FIG. 1 and viewed in the direction of the arrows.
DESCRIPTION OF THE INVENTION
Table T, as best shown in FIG. 1, includes circular rim 10 which surrounds glass top 12. Legs 14, 16, 18 and 20 are secured to rim 10 by clips C, as will be further explained.
Rim 10, as best shown in FIG. 5, has upper flange 22 which is connected to vertical section 24. Lower flange 26 extends from vertical section 24 in alignment with upper flange 22. Lower flange 26 has gently rounded lip 28 extending upwardly therefrom toward upper flange 22. The lip 28 forms a groove or annular recess 30 with straight wall section 32 of vertical section 24. Preferably, upper flange 22 has a lower flat surface 34 extending generally transverse to wall section 32.
Clip C, as best shown in FIG. 3, includes a flat vertical element 36 from which support 38 extends transversely thereto. Vertical positioning element 40 extends from support 38 in alignment with flat element 36, for reasons to be explained.
First leg member 42 extends from flat element 36 in general alignment with and spaced from support 38. Second leg member 44 extends from integral hinge 46 of first leg member 42. In this way, the leg members 42 and 44 are juxtaposed and have a generally U-shaped opening 48 extending therebetween. Groove 50 extends along second leg member 44 adjacent end 52 thereof and has a shape conforming to the shape of lip 28, for reasons to be explained.
Screws 54 extend through threaded holes 56, only one of which is illustrated in FIG. 5, in second leg member 44 and bear upon first leg member 42.
Support 38 has an upper flat surface 58 and a lower flab surface 60, as best shown in FIG. 5. Similarly, first leg member 42 has an upper flat surface 62 and a lower flat surface 64 upon which the screws 54 bear. Also, flat element 36 has first and second flat surfaces 66 and 68, for reasons to be explained.
Each of the legs 14, 16, 18 and 20 has an end 70 which is secured to flat surface 66, preferably by welding or the like. Each of the legs is, preferably, of tubular construction and has conforming secured together tubular elements 72 and 74. The tubular elements 72 and 74 have a height or diameter substantially equal to the distance separating lower surface 60 from upper surface 62 so that the tubular elements 72 and 74 are sandwiched therebetween. Also, the elements 72 and 74 may thereby be secured to the support 38, such as by welding or the like.
The rim 10 is, preferably, made of metal, such as extruded aluminum. I prefer this material because it is relatively inexpensive, can be readily formed into a desired shape and is lightweight. Also, preferably, the legs 14, 16, 18 and 20 are likewise formed of extruded aluminum for similar reasons. The clips C are also of extruded aluminum, although they could be made of a tough plastic, so that the leg members 42 and 44 can flex about hinge 46. Extruded aluminum does have sufficient elasticity to permit the legs 42 and 44 to flex apart to a sufficient extent for my purposes.
Assembly of the table T and attachment of the legs 14, 16, 18 and 20 through use of the clips C is relatively straightforward, requires no special tools and can be done quite rapidly. In fact, disassembly can likewise be accomplished rapidly in order to permit thorough cleaning of the table T and its related components.
The glass top 12 is, preferably, secured to rim 10. The top 12 is, preferably, adhesively secured to flat surface 34 in order to be permanently affixed thereto.
Each of the legs 14, 16, 18 and 20 is secured to one of the clips C, such as by welding. As noted, the end 70 is positioned contiguous with flat surface 66 in order to properly align the associated leg within the clip C, thereby assuring that each leg will position the top 12 at the same height relative to the floor. The clips C are each inserted between the flanges 22 and 26 so that the vertical element 40 is positioned between the edge 76 of top 12 and wall section 32 and support 38 engages top 12. Similarly, groove 50 is positioned onto lip 28 so that end 52 is received within groove 30. The clip C is thereby loosely positioned within rim 10 and can be slid about the rim 10 to the appropriate position. After being properly circumferentially positioned about rim 10, then the screws 54 are tightened so that the members 42 and 44 are caused to flex about hinge 46. Flexing of the members 42 and 44 cause the leg member 44 to be securely positioned against the lip 20 while the upper surface 58 of support 38 is securely pressed against top 12. Both screws 54 should be tightened so that the clip C is locked in position within rim 10.
I have found that disassembly of the table T can likewise be performed rapidly in order to permit top 12 to be cleaned or replaced. All that is required is that the screws 54 be loosened, so that the leg members 42 and 44 return to their initial unstressed position, thereby once again loosely positioning the clip C between the flanges 22 and 26. The clip C can then be removed from the rim 10 by merely removing the groove 50 from the keying lip 28.
Those skilled in the art will understand that the clip C of the invention can be used to fit a wide variety of rims 10 or legs simply by changing the appropriate dimensions of the rim 10 and the clip C. Furthermore, the rim 10 can have any desired configuration, and need not be circular as shown in FIG. 1. The clip C of the invention, in combination with the rim 10 provides secure attachment of the legs to the rim 10 in a manner achieving rigidity greater than that available in the prior art, and merely requires a screwdriver.
While this invention has been described as having a preferred design, it is understood that it is capable of further modifications, uses and/or adaptations of the invention following in general the principle of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains, and as may be applied to the central features hereinbefore set forth, and fall within the scope of the invention of the limits of the appended claims. | An assembly for securing a leg of a table or the like comprises a table top including first and second spaced flanges. A clip for being secured to a leg includes a first support engageable with the first flange and first and second juxtaposed hingedly connected leg members, with one of the members engageable with the second flange. A screw forces the members apart so that the first support is forced securely against the first flange and the one member is forced securely against the second flange. | 0 |
[0001] This application claims the benefit of Korean Application No. P2003-093200, filed on Dec. 18, 2003, which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a dryer accessory, and more particularly, to a laundry separator for compartmentalized drying, which is loaded as an accessory in a dryer or a washer having a drying function.
[0004] 2. Discussion of the Related Art
[0005] Generally speaking, a dryer or washer having a drying function is an apparatus for drying objects such as a laundry contained in a drum by supplying hot air to the drum. To enhance drying performance, a plurality of lifters are provided within the drum, as shown in FIG. 1 illustrating the drum of a general dryer or washer-dryer. Here, the lifters and drum are individually manufactured, and then the lifters are installed inside the drum.
[0006] Referring to FIG. 1 , a plurality of locking members 3 (e.g., screws) is used to install a plurality of lifters 2 on an inner surface of a drum 1 . As an alternative, the lifters 2 may be formed by pressing the drum 1 to deform its inner circumferential surface.
[0007] In drying an object to be dried, the corresponding object held within the drum 1 is lifted by the lifters 2 up to a predetermined height and then dropped. The object is easily exposed to hot air supplied to the drum 1 to be evenly dried, thereby enhancing drying efficiency.
[0008] However, in the above-constructed dryer or washer having the drying function, it is impossible to dry various kinds of drying objects or various colored drying objects at the same time. For instance, some kinds of drying objects are easily decolorized. If such a kind of a drying object is dried together with a white drying object, the white drying object tends to get dyed. In order to overcome such a problem, drying objects should be sorted according to types and colors to be separately dried, which is time consuming and inconvenient and wastes electricity.
SUMMARY OF THE INVENTION
[0009] Accordingly, the present invention is directed to a laundry separator for compartmentalized drying that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
[0010] An object of the present invention, which has been devised to solve the foregoing problem, lies in providing a laundry separator for compartmentalized drying, which is loaded in a drum of a dryer or washer having a drying function and by which various type or colored drying objects are sorted to be dried at the same time.
[0011] Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent to those having ordinary skill in the art upon examination of the following or may be learned from a practice of the invention. The objectives and other advantages of the invention will be realized and attained by the subject matter particularly pointed out in the specification and claims hereof as well as in the appended drawings.
[0012] To achieve these objects and other advantages in accordance with the present invention, as embodied and broadly described herein, a laundry separator for compartmentalized drying, includes at least one divider for detachable installation in a drum for drying laundry, wherein the at least one divider partitions an inner space of the drum into a plurality of spaces.
[0013] In another aspect of the present invention, a laundry separator for compartmentalized drying includes a shaft for being detachably installed lengthwise in a drum of an appliance having a drying function, and a plurality of dividers radiating from the shaft to partition an inner space of the drum into a plurality of spaces.
[0014] The at least one divider is provided radially with respect to the drum. And, the at least one divider has a distal end for coupling to a lifter protruding inwardly from the drum.
[0015] Preferably, the at least one divider has a multitude of apertures for allowing airflow between the plurality of spaces. Herein, the apertures extend radially from the shaft.
[0016] Preferably, the at least one divider has a length corresponding to an inner length of the drum. Herein, each divider has an axial length substantially equal to an interior space of the drum.
[0017] Preferably, the at least one divider has elasticity in a radial direction of the drum. And, the at least one divider has elasticity in a circumferential direction of the drum.
[0018] Preferably, when installed, the shaft is aligned with the central axis of the drum. Herein, the shaft includes a tube having an outer circumference, the dividers radiating from the outer circumference. The shaft has elasticity in a radial direction.
[0019] Preferably, the laundry separator may include a plurality of elastic members, each connecting an opposing side of the dividers, to reinforce elasticity of the dividers in a circumferential direction of the drum. Herein, each elastic member has a curved surface on a same central axis of the shaft. Each divider includes two sides forming a recess in a distal end for receiving a lifter.
[0020] Preferably, the dividers are configured as adjacent pairs, each pair forming a gap in which a lifter protruding from an inner surface of the drum can be fitted. The laundry separator may include a plurality of elastic members, each connecting an opposing side of the dividers, to reinforce a gripping force applied to the lifter. Herein, each elastic member has a curved surface on a same central axis of the shaft.
[0021] It is to be understood that both the foregoing explanation and the following detailed description of the present invention are exemplary and illustrative and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention. In the drawings:
[0023] FIG. 1 is a cross-sectional diagram of a drum of a general dryer or washer-dryer;
[0024] FIG. 2 is a cross-sectional diagram of a dryer in which a laundry separator according to the present invention is installed;
[0025] FIG. 3 is a perspective diagram of a laundry separator according to a first embodiment of the present invention;
[0026] FIG. 4 is a cross-sectional diagram of the laundry separator in FIG. 3 loaded in a drum;
[0027] FIG. 5 is a perspective diagram of a laundry separator according to a second embodiment of the present invention; and
[0028] FIG. 6 is a perspective diagram of a laundry separator according to a third embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Throughout the drawings, like elements are indicated using the same or similar reference designations where possible.
[0030] A laundry separator according to the present invention can be installed and used in an exhaust-type dryer, condensing-type dryer, washer/dryer, or the like. In the exhaust type dryer, external air is heated to be supplied to a drum and humid air having dried a drying object within the drum is discharged. In the condensing type dryer, air, which is humid after having dried a drying object within a drum, is condensed by a condenser to lower the humidity and is then heated to be re-supplied to the drum. The laundry separator according to the present invention as described herein is to be installed in the exhaust type dryer as an example but is appropriate for installation in any appliance having a drum for performing a drying function.
[0031] Referring to FIG. 2 , a drum 20 is rotatably provided within a cabinet 10 of a dryer. The drum 20 has a cylindrical shape, and a plurality of lifters 25 protrude from an inner surface of the drum 20 . The lifter 25 and the drum 20 are separately manufactured. Hence, the lifter 25 is attached to the inside of the drum 20 later. Instead, the lifters 25 may be integrally formed with the drum 20 . A front panel 21 and rear panel 23 are respectively mounted on an open front side and open rear side of the drum 20 , which is rotatably supported by the front and rear panels 21 and 23 during dryer operation. That is, while the dryer is operated, the drum is rotated but the front and rear panels 21 and 23 remain stationary. An opening 21 a is provided to the front panel 21 , and a door 15 is installed on the front side of the cabinet 10 to open/close the opening 21 a . An exhaust duct 30 is connected to the front panel 21 . Hence, the interior of the drum 20 communicates via the exhaust duct 30 with an external environment with respect to the cabinet 10 . A fan 40 for expelling the air in the drum 20 and a filter 35 filtering the air expelled by the fan 40 are provided within the exhaust duct 30 . The fan 40 is rotated by a motor 50 provided within the cabinet 10 to rotate both the fan 40 and the drum 20 . For this, the motor 50 includes a pair of shafts respectively connected to the fan 40 and a pulley 60 connected to the drum 20 via a belt 65 . Though not specifically shown, the motor 50 may rotate the fan 40 only. An air inlet duct 70 is connected to the rear panel 23 to enable the inside of the drum 20 to communicate with an external environment. As the fan 40 rotates to discharge the air within the drum 20 outside via the exhaust duct 30 , external air is supplied into the drum 20 via the air inlet duct 70 . A heater 80 is installed in the air inlet duct 70 to supply hot air into the drum 20 .
[0032] A laundry separator 100 according to the present invention is installed in the drum 20 . The laundry separator 100 according to the present invention is detachably installed in the drum 20 and partitions an inner space of the drum 20 into a plurality of partitioned spaces. Hence, a user puts drying objects sorted according to types and colors in a plurality of the spaces partitioned by the laundry separator 100 and then operates the dryer to dry the drying objects of various colors and types at the same time.
[0033] Referring to FIG. 3 , a shaft 110 and a plurality of dividers 150 are provided to the laundry separator 100 according to the present invention. The shaft 110 is inserted along a length direction of the drum 20 , and a plurality of the dividers 150 extend from the shaft 110 to partition an inner space of the drum 20 into a plurality of partitioned spaces. In the embodiment shown in FIG. 3 , the shaft 110 includes a long tube that is hollow. Preferably, the shaft 100 has the same length of a front-to-rear length of the drum 20 and the same central axis of the drum 20 . Each of the dividers 150 extends out of an outer circumference of the tube in a radial direction of the drum 20 .
[0034] The shaft 110 may be formed of a substantially rigid material but may be imparted with some elasticity in its radial direction. Each of the dividers 150 extending from the outer circumference of the shaft 110 in the radial direction of the drum 20 may have elasticity in the radial direction of the drum 20 . The dividers 150 extend from the circumference of the shaft 110 in the same direction of the shaft 110 or drum 20 . Preferably, each of the dividers 150 has the same length of the shaft 110 and is installed to be nearly in contact with both front and rear insides of the drum 20 when the laundry separator 100 is loaded in the drum 20 . Then, the inner space of the drum 20 is partitioned into a plurality of spaces by the laundry separator 100 so that drying objects respectively held in the partitioned spaces are not loaded together.
[0035] A multitude of apertures 155 are provided to each of the dividers 150 so that air can pass through the apertures 155 . Each of the apertures 155 is formed long in the radial direction of the drum 20 , for example. Once the apertures 155 are provided to the dividers 150 , hot air supplied to the drum 20 flows throughout the spaces created by the dividers 150 via the apertures 155 , to uniformly dry the drying objects in each space.
[0036] As shown in FIG. 4 , an outer end of each of the dividers 150 is coupled to the corresponding lifter 25 to be fixed thereto. For this, the dividers 150 are arranged in adjacent pairs so that the corresponding lifter 25 can be fitted in a gap G exiting between the corresponding pair of the dividers 150 to install the laundry separator 100 according to the present invention in the drum 20 stably and securely. The distance, i.e., the gap G, between the sides of an adjacent pair of dividers 150 is preferably set smaller than the thickness of any lifter 25 , so that the adjacent pair of dividers 150 provides a gripping force acting on the lifter. For this, the laundry separator 100 is provided with an elastic member 130 between opposing sides of each adjacent pair of dividers 150 to provide the respective dividers 150 with elasticity in a circumferential direction of the drum 20 . Specifically, the elastic member 130 is provided to connect two dividers 150 , thereby reinforcing the gripping force of the dividers 150 , to fit onto the lifters securely and firmly, with little or no incidental movement, and thereby support a load of wet laundry and prevent excess noise, such as rattling or knocking, during dryer operation. The elastic member 130 has a circular cross-section on the same central axis of the shaft 110 .
[0037] In the embodiment of FIG. 5 , the dividers 150 of the laundry separator 100 according to the present invention are structurally modified to provide a recess 151 formed in the distal end of each of a plurality of dividers 150 ′ for receiving a lifter 25 . The lifters 25 are respectively fitted in the recesses 151 of each divider 150 ′, whereby the laundry separator 100 can be stably loaded in the drum 20 .
[0038] In the embodiment of FIG. 6 , a plurality of the dividers 150 □are centrally connected without a shaft 110 or an elastic member 130 . In this case, the axis of the laundry separator 100 is defined by the circumference of the drum 20 as determined by the location of the mounting lifters.
[0039] Meanwhile, although not specifically shown in the drawings, a further embodiment of the laundry separator of the present invention may include a structurally modified shaft, in which the diameter of the shaft is large enough to provide an additional space for accommodating laundry to be dried separately from that held in the spaces partitioned by the dividers.
[0040] Moreover, rather than the dividers of the above-described embodiments, which radiate from a central point along the full length of the shaft to provide a plurality of partitioned spaces in the shape of wedges, the laundry separator of the present invention could be provided with dividers that radiate from a plurality of points along the length of the shaft to provide a plurality of alternatively partitioned spaces in the shape of wheels.
[0041] In using the laundry separator 100 for drying various objects of differing in color and/or type, the laundry separator 100 is installed within the drum 20 so that the shaft 110 is located on the central axis of the drum 20 . In doing so, a plurality of the dividers 150 can be elastically deformed in the same radial direction of the shaft 110 or drum 20 and their circumferential directions, respectively, whereby a user is facilitated to install the laundry separator 100 within the drum 20 .
[0042] After completion of installing the laundry separator 100 , the lifter 25 of the drum 20 is fitted in the gap G between adjacent dividers 150 or in the recess 151 formed at the distal end of each divider 150 ′, thereby being stably fixed thereto. Thus, while the laundry separator 100 is stably loaded in the drum 20 , the drying objects sorted according to types and/or colors are placed in the spaces partitioned by the dividers 150 as desired.
[0043] With the laundry separator 100 thus installed, the door 15 is closed and the dryer is then actuated. The drum 20 is rotated by the motor 50 , pulley 60 , and belt 65 so that the drying objects held in the respective spaces partitioned by the laundry separator 100 are repeatedly lifted upward to fall within the respective partitioned spaces by the rotational force of the drum 20 . Meanwhile, the fan 40 rotates and the heater 80 heats the air. The heated air is supplied to the drum 20 via the air inlet duct 70 , as the air within the drum 20 is discharged via the exhaust duct 30 .
[0044] The heated air supplied to the drum 20 flows in the spaces partitioned by the dividers 150 to dry the drying objects. In doing so, the heated air can travel to other spaces via the apertures 155 provided to the dividers 150 , thereby uniformly drying the drying objects in each of the partitioned spaces.
[0045] The air, which becomes humid air after drying the drying objects within the drum 20 , is then discharged outside via the exhaust duct 30 . In doing so, particles contained in the humid air are removed by the filter 35 so that clean air can be discharged.
[0046] If no sorting of the drying objects is desired, the laundry separator 100 is removed from the drum 20 . In doing so, the dividers 150 are elastically deformed in the radial and circumferential directions of the shaft 110 and drum 20 , to facilitate the removal of the laundry separator 100 from the drum 20 .
[0047] As described above, the laundry separator according to the present invention is detachably installed in the drum of the dryer or washer/dryer to partition the inner space of the drum 20 into a plurality of spaces. Accordingly, a user puts the drying objects sorted according to colors and/or types in the partitioned spaces within the drum, respectively, whereby the entire drying objects can be dried at the same time. Therefore, the drying objects can be easily dried, the corresponding drying time is shortened, and power consumption can be considerably saved.
[0048] It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover such modifications and variations, provided they come within the scope of the appended claims and their equivalents. | A laundry separator for compartmentalized drying is loaded in the drum of a dryer, or in the drum of a washer having a drying function, as an accessory enabling simultaneous drying of laundry sorted according to type, color, and so on. The laundry separator for compartmentalized drying, includes at least one divider for detachable installation in a drum for drying laundry, wherein the at least one divider partitions an inner space of the drum into a plurality of spaces. | 3 |
FIELD OF THE INVENTION
The present invention relates to a method and a device for controlling the alignment between refining surfaces of two opposite refining discs rotatable in relation to each other, so that the gap width of the refining gap between the refining surfaces of the refining discs is kept constant for every diameter for a complete revolution, which refining discs are included in the refining apparatus for disintegrating and refining lignocellulose-containing material in a refining gap between the refining surfaces of the refining discs. More particularly, the present invention also relates to a refining apparatus for disintegrating and refining lignocellulose-containing material in a refining gap between the refining surfaces of two opposite refining discs rotatable in relation to each other, comprising a device for controlling the alignment between the refining surfaces.
BACKGROUND OF THE INVENTION
Refining apparatus or disc refiners of the type discussed above are used, inter alia, for highly concentrated refining, CTMP, TMP, fluffing and highly concentrated grinding of sack paper and other lignocellulose-containing material. They usually comprise two opposite refining discs rotatable in relation to each other, where often one refining disc is rotatable, a so called rotor, and the other refining disc is non-rotatable, a so called stator, but in some refining apparatus both refining discs are rotatably arranged. Refining discs in this type of refining apparatus are provided with exchangeable refining segments which build up the refining surfaces of the refining apparatus. The refining segments comprise bars and intermediate grooves. Grinding occurs between the two refining surfaces which are kept at a certain distance from each other, whereby a space, a so called refining gap, is provided between the refining surfaces.
If the refining surfaces were to come into contact with each other during operation, there is a risk of breakdown or at least wear on the refining surfaces, and with that a shortened operating performance. Furthermore, the degree of alignment between the refining surfaces has great significance regarding the quality of the ground material. When the degree of alignment between the refining surfaces is reduced, the quality of the ground material deteriorates. An accurate control of the refining gap and the alignment between the refining surfaces is thus of great importance.
One way of measuring the distance between the refining surfaces in a refining apparatus is disclosed in Swedish Patent No. 416,844, which discloses a device and a method for measuring the distance between two opposite surfaces, made of a magnetic conducting material, according to the reluctance method by means of a position sensor which is provided in one of the surfaces and is orientated in relation to the second surface so that the air gap between the surfaces is included in the circuit. The method comprises the use of a sensor having two windings provided around a core, which are supplied with current so that they work in opposite directions, and the currents are controlled so that the resulting magnetic flux through a direct current field meter located between the windings is always kept equal to zero, whereby the measurement result is attained by measuring the difference between the currents supplied to the windings. It is also known to make such a sensor displaceable from one of the surfaces towards the other surface, for position calibration.
Swedish Patent No. 463,396 discloses a device for indicating the axial contact position of the refining surfaces of two opposite refining discs rotatable in relation to each other and included in a disc refiner. A sensor sensing heat radiation is arranged to detect the heat radiation which arises through the friction as two refining surfaces contact each other during rotation in relation to each other. The sensor is positioned radially outside the refining discs.
Swedish Patent No. 454,189 describes a method for controlling the production of mechanical pulp in a refiner process, where lignocellulose-containing material in pieces is refined when passing through the refining gap between two opposite refining discs rotating in relation to each other. The vibrations of at least one of the refining discs are measured by means of an accelerometer provided in the refining disc and are transformed to vibration energy, which, together with one or several of the process variables: production, size of the refining gap and material concentration, is used for controlling the properties of the produced pulp. Further, Swedish Patent No. 454,189 discloses that the condition of the refining segment can also be established by the measured vibrational energy, which can be used for determining when it is time for exchanging refining segments, and different refining segment patterns and refining segment material can be compared.
British Patent No. 1,468,649 discloses a method for adjusting the refining surfaces included in a refining apparatus, so that these are parallel when grinding wood chips into pulp, which refining apparatus comprises a stationary refining disc and a rotatable refining disc, the stationary refining disc being attached to the frame of the refining apparatus by means of three fixing pins of which at least one is heatable for instance by an electric current, so that its length is variable to achieve parallelism between the refining surfaces of the refining discs. The method comprises the steps of continuously measuring the axial force between the refining surfaces and maintaining this force at its maximum by shortening or lengthening the length of the heatable fixing pin. This force is measured by measuring means provided on the rotation axis of the rotatable refining disc.
However, the method of British Patent No. 1,468,649 assumes that the material intended for grinding has a certain moisture content, which is defined as a dry matter content between about 15 and 40%, so that steam is generated between the refining surfaces, whereby this steam gives rise to the greater part of the pressure between the refining surfaces. The method is based on the conclusion that when the degree of parallelism between the refining surfaces reduces, the pressure between the refining surfaces is reduced, which pressure reduction can be measured as a reduction of the axial force. When the pressure is at its maximum, the degree of parallelism is considered to be maximized. However, this means that when the material intended for grinding changes, for example regarding type, size and dry matter content, or the temperature in the refining gap changes, the size of the maximum force attained when the degree of parallelism or alignment between the refining surfaces is at its maximum also changes.
One of the objects of the present invention is thus to provide a method and a device which more effectively control the alignment between two opposite refining surfaces rotatable in relation to each other, which refining surfaces are included in a refining apparatus, in relation to the prior art. Another object hereof is to provide a refining apparatus provided with such a device.
SUMMARY OF THE INVENTION
In accordance with a the present invention, these and other objects have now been realized by the discovery of a method for controlling the alignment between a pair of juxtaposed refining surfaces associated with a corresponding pair of refining discs which are relatively rotatable with respect to each other, and which are incorporated into a refiner for disintegrating and refining lignocellulose-containing material in a refining gap disposed between the pair of refining surfaces, the method comprising positioning at least three sensors in at least three predetermined measurement positions disposed with respect to the refining gap, measuring the vibrations at each of the at least three predetermined measurement positions during operation of the refiner by means of the at least three sensors, and comparing each of the measured vibrations at each of the at least three predetermined measurement positions with each other. Preferably, the method includes adjusting at least one of the pair of refining discs based on the comparison of the measured vibrations until the measured vibrations at each of the at least three predetermined measurement positions is substantially the same, thereby obtaining correct alignment between the pair of refining surfaces. Preferably, at least one of the comparing and adjusting steps is carried out during operation of the refiner.
In accordance with one embodiment of the method of the present invention, the measuring of the vibrations is performed on the same one of the pair of refining discs. Preferably the measuring of the vibrations is performed on the same one of the pair of refining discs in proximity to the one of the pair of refining surfaces associated with the one of the pair of refining discs.
In accordance with another embodiment of the method of the present invention, the measuring of the vibrations comprises measuring at least the amplitude of the vibrations at each of the at least three predetermined measurement positions.
In accordance with the present invention, these and other objects have also been realized by the invention of apparatus for controlling the alignment between a pair of juxtaposed refining surfaces in a refiner for disintegrating and refining lignocellulose-containing material comprising a pair of relatively rotatable refining discs, each for mounting one of the pair of refining surfaces thereby defining a refining gap therebetween, at least three sensors disposed in at least three predetermined measurement positions disposed with respect to the refining gap and the pair of refining discs, each of the at least three sensors comprising a vibration sensor disposed on one of the pair of refining discs for measuring the vibrations at each of the three predetermined measurement positions, whereby the measuring can take place during operation of the refiner, and comparison means for comparing the measurements of the at least three predetermined measurement positions to provide a comparison therebetween. Preferably, the apparatus includes adjusting means for adjusting one of the pair of refining surfaces mounted on one of the pair of refining discs based on the comparison, whereby a correct alignment can be obtained between the pair of refining surfaces when substantially equal measurements are obtained at all of the at least three predetermined measurement positions. In a preferred embodiment, at least one of the comparison means and the adjustment means is adapted for carrying out the comparison or adjustment during operation of the refiner.
In accordance with another embodiment of the apparatus of the present invention, the vibration sensors are capable of measuring at least the amplitude of the vibrations.
In accordance with another embodiment of the apparatus of the present invention, the at least three sensors are symmetrically distributed along the periphery of one of the pair of refiner discs.
In accordance with the present invention, refining apparatus for disintegrating and refining lignocellulose-containing material in the refining gap between a pair or refining surfaces mounted on a pair of relatively rotatable refining discs has been devised comprising alignment controlling means including the apparatus discussed above.
The objects of the present invention are achieved by providing a method of the type discussed above. By the above-discussed measurement and comparison, a more effective control of the alignment between the refining surfaces is attained, so that the gap width of the refining gap between the refining surfaces of the refining discs is kept constant for every diameter of the refining surface for a complete revolution, and this is achieved independent of changes in the material intended for grinding, for example changes in dry matter content, size, etc., or in the environment, for example changes in temperature or wear on the refining segment, in the region of the refining gap and refining discs. This results in an improved quality of the ground material, and the number of interruptions of operation of the refiner are kept at a minimum.
According to an advantageous embodiment of the method according to the present invention, the method comprises adjustment of the refining surface of at least one of the refining discs based on the comparison until substantially equal measurement results are obtained at all of the measurement positions, whereby a correct alignment is attained between the refining surfaces, so that the gap width is kept constant for every diameter for a complete revolution. By “substantially equal” is meant that the measurement results from all measurement positions are within a range which is common and so limited that a satisfactory high degree of alignment between the refining surfaces is attained. This range should be within about 10% of the gap width, suitably within about 5% of the gap width, where the gap width is normally about 0.5 to 2 mm. The adjustment can, for example, be performed manually, for example by means of adjusting knobs, or by means of an automatic displacement of the refining surface, as described in British Patent No. 1,468,649, or by connecting electrical stepping motors to the above-mentioned adjusting knobs. By this measurement, comparison and/or adjustment, a more effective control of the alignment between the refining surfaces is achieved, especially since the invention enables effective control during operation, and where performing the measurement, comparison and/or adjustment during operation, during idle running and/or grinding, is an advantageous embodiment of the method according to the present invention.
The measurement is achieved by at least three sensors which are positioned at different measurement positions.
Alternatively, the measurement at the at least three measurement positions comprises non-contact measurement of the distance between the refining surfaces at each measurement position. This measurement can, for example, be performed by means of laser, by means of the reluctance method which is disclosed in Swedish Patent No. 416,844, etc.
According to the present invention, the measurement at the at least three measurement positions comprises measuring the vibrations at each measurement position. Alternatively, the measurement can, for example, comprise measuring the temperature at each measurement position, or measuring other parameters based upon which the alignment can be controlled by the present invention.
The above-mentioned objects are also achieved by providing a device of the kind defined here above. In this manner, more effective control of the alignment between the refining surfaces is attained so that the gap width is kept constant for every diameter of the refining surface for a complete revolution, and this is achieved independently of a change in the material intended for grinding, or in the environment of the region refining gap and refining discs. Furthermore, a device is provided which is uncomplicated and easy to install, both in connection with the assembly or set-up of the refining apparatus, or afterwards when the refining apparatus is already assembled or set-up, and consequently, subsequent installation is not expensive.
According to an advantageous embodiment of the device according to the present invention, the device comprises adjusting means for adjusting the refining surface of at least one of the refining discs based on the comparison of the comparison means, until substantially equal measurement results are obtained at all of the measurement positions, whereby a correct alignment is attained between the refining surfaces, so that the gap width is kept constant for every diameter for a complete revolution. Advantageously, the number of adjusting means is at least three, and can comprise fixing pins which are disclosed in connection with British Patent No. 1,468,649. By “substantially equal” is meant the same as clarified above in connection with the method. By this measuring equipment, comparison means and adjusting means, a more effective control of the alignment between the refining surfaces is provided, especially in light of the fact that the device enables effective control during operation, and where an advantageous embodiment of the device according to the present invention is the fact that measuring equipment, comparison means and/or adjusting means are/is arranged to perform the measurement, comparison and/or adjustment during operation, during idle running and/or during grinding.
The measuring equipment of the device of the present invention comprises at least three sensors which are provided at different measurement positions.
Alternatively, each sensor consists of a distance meter for non-contact measurement of the distance between the refining surfaces at the respective measurement positions. Examples of advantageous distance meters are laser meters, inductive distance meters which are disclosed in Swedish Patent No. 416,844 and which are displaceably arranged, etc.
According to further advantageous embodiments of the device according to the present invention, each vibration sensor, provided at one of the refining discs for measuring the vibrations at the respective measurement positions, consists for instance of an accelerometer, microphone etc. Alternatively, temperature sensors for measuring the temperature can also be provided at each measurement position, or other sensors for measuring other parameters, based upon which the alignment can be controlled by the present invention.
The above-mentioned objects are also attained by providing a refining apparatus of the kind defined here above.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be described in more detail, for exemplary purposes, in the following detailed description which, in turn, refers to the enclosed drawings, in which:
FIG. 1 is a side, elevational, cross-sectional, partially schematic view of a refining apparatus, in connection with a schematic block diagram illustrating a first embodiment of the device according to the present invention;
FIG. 2 is a side, elevational, cross-sectional, partially schematic view of a refining apparatus in connection with a schematic block diagram illustrating a second embodiment of the device according to the present invention;
FIG. 3 is a front, elevational, partially schematic view showing an advantageous placement of the sensors of the first embodiment of the present invention shown in FIG. 1 ;
FIG. 4 is a front, elevational, partially schematic view showing an advantageous placement of the sensors of the second embodiment of the present invention shown in FIG. 2 ;
FIG. 5 is a front view of a flow diagram illustrating a first embodiment of the method according to the present invention;
FIG. 6 is a front view of a flow diagram illustrating a second embodiment of the method according to the present invention; and
FIG. 7 is a diagrammatical representation showing the relation between the vibration level of the stator and the change in refining gap of a refiner in accordance with the present invention.
DETAILED DESCRIPTION
Turning to the Figures, in which like reference numerals refer to corresponding elements thereof, FIG. 1 shows a first embodiment of the device according to the present invention, connected to a refining apparatus, a so called disc refiner, of which only the refining housing is shown in FIG. 1 in cross-section, for disintegrating and refining lignocellulose-containing material in a refining gap 102 between refining surfaces, 103 and 104 , of two opposite refining discs, 105 and 106 , which are rotatable in relation to each other, in the form of a rotatable rotor 105 and a non-rotatable stator 106 . The device comprises measuring equipment for measuring at least three different measurement positions in the region of the refining gap 102 and the refining surfaces, 103 and 104 , which measuring equipment comprises three inductive position sensors, 107 , 108 and 109 , provided at three different positions at the refining surface 104 of the stator 106 , for measurement according to the reluctance method, where each position sensor, 107 , 108 and 109 , is orientated in relation to the refining surface of the rotor 105 so that the refining gap 102 and the refining surface 103 of the rotor 105 are included as part of the circuit, the reluctance of which is measured, and so that each position sensor, 107 , 108 and 109 , is pushable out from the refining surface 104 of the stator 106 for moving into contact with the refining surface 104 of the rotor 105 , for calibration. Each position sensor, 107 , 108 and 109 , comprises two windings provided around a core, which are supplied with current so that they work in opposite directions and the currents are controlled so that the resulting magnetic flux through a direct current field meter located between the windings is always kept equal to zero, and the difference between the currents supplied to the windings is measured. A corresponding position sensor is disclosed in Swedish Patent No. 416,844. Furthermore, the measuring equipment comprises current generators 110 for feeding current to the position sensors, 107 , 108 and 109 , control means 111 for controlling the displacement and calibration of the position sensors, 107 , 108 and 109 , and signal processing means 112 for processing the signals from the position sensors 107 , 108 , 109 . The device comprises a control device 113 which is connected to the current generators 110 , the control means 111 and the signal processing means 112 , from which the control device 113 receives signals. Furthermore, the control device 113 is connected to three adjusting means, 114 , 115 and 117 , for advantageously adjusting the refining surface 104 of the stator 106 , the adjusting means, 114 , 115 and 117 , being evenly distributed around the circumference. The control device 113 comprises comparison means 116 for comparing the measurement results of the position sensors, 107 , 108 and 109 , with each other, and correct alignment is established if these measurement results are substantially equal. The control device 113 is arranged to control the adjusting means, 114 , 115 and 117 , for adjusting the refining surface 104 of the stator 106 based on the comparison by the comparison means 116 until substantially equal measurement results are obtained from the three position sensors, 107 , 108 and 109 , whereby correct alignment between the refining surfaces, 103 and 104 , is attained. The measuring equipment, 107 , 108 , 109 , 110 , 111 and 112 , the comparison means 116 and the adjusting means, 114 , 115 and 117 , are arranged to perform this measurement, comparison and adjustment during operation.
FIG. 2 shows a second embodiment of the device according to the present invention, connected to a refining apparatus 201 , in the form of a so called CD-refiner (Conical Disc), of which only the refining housing is shown in FIG. 2 , in cross-section. The device comprises measuring equipment for measuring at four different measurement positions in the region of the refining gap 202 and the refining discs, 205 and 206 , a rotor 205 and a stator 206 , which measuring equipment comprises four vibration sensors, 207 , 208 , 209 and 210 , in the form of four accelerometers, 207 , 208 , 209 and 210 , provided at four different positions at the stator 206 for measuring the vibrations at the respective measurement position. In this embodiment, the accelerometers, 207 , 208 , 209 and 210 , are provided at that side of the stator 206 which is opposite the refining surface 204 and are attached to the bolts 220 , the purpose of which are to keep the refining disc 206 with refining segments in position, which refining segments build up the refining surface 204 . Thus, these bolts 220 transmit vibrations from the refining surface 204 to the opposite side of the stator 204 and to each accelerometer 207 , 208 , 209 , 210 . This is an effective installation of the accelerometers, 207 , 208 , 209 and 210 , when the device is installed afterwards when the refining apparatus is already assembled or set-up. However, other installation positions of the accelerometers, 207 , 208 , 209 and 210 , are also possible. If the device is installed at the same time as the refining apparatus is assembled, the accelerometers, 207 , 208 , 209 and 210 , are advantageously positioned as close to the refining surface as possible, for example immediately under said refining segments. The accelerometers, 207 , 208 , 209 and 210 , are arranged to measure the amplitude and frequency of the vibrations at the respective measurement position. Furthermore, the measuring equipment comprises a current generator 211 for feeding current to the accelerometers, 207 , 208 , 209 and 210 , filtering means 212 for filtering the signals received from the accelerometers, 207 , 208 , 209 and 210 , and sampling means 213 for sampling the filtered signals. The device comprises a control device 214 which is connected to the current generator 211 , the filter means 212 and the sampling means 213 from which the control device 214 receives the sampled signals. Furthermore, the control device 214 is connected to three adjusting means, 215 , 216 and 218 , for advantageously adjusting the refining surface 204 of the stator 206 , the adjusting means, 215 , 216 and 218 , being evenly distributed around the circumference. The control device 214 comprises comparison means 217 for comparing the measurement results of the accelerometers, 207 , 208 , 209 and 210 , with each other, and correct alignment is established if these measurement results are substantially equal. The control device 214 is arranged to control the adjusting means, 215 , 216 and 218 , for adjusting the refining surface 204 of the stator 206 based on the comparison by the comparison means 217 until substantially equal measurement results are obtained from the four vibration sensors, 207 , 208 , 209 and 210 , whereby correct alignment between the refining surfaces, 203 and 204 , is attained. The measuring equipment, 207 , 208 , 209 , 210 , 211 , 212 and 213 , the comparison means 217 and the adjusting means, 215 , 216 and 218 , are arranged to perform this measurement, comparison and adjustment during operation.
FIG. 3 shows a front view of the stator 106 of FIG. 1 in cross-section, and shows schematically an advantageous placement of the position sensors, 107 , 108 and 109 . The position sensors, 107 , 108 and 109 , are installed at the refining surface 106 of the stator 106 substantially along one and the same diameter of this refining surface.
FIG. 4 shows a front view of the stator 206 of FIG. 2 in cross-section, and shows schematically an advantageous placement of the vibration sensors, 207 , 208 , 209 and 210 . The vibration sensors, 207 , 208 , 209 and 210 , are positioned substantially symmetrically along the periphery of the refining surface 204 of the stator 206 .
Although the sensors of the above-mentioned embodiments are installed at the stator, it is also possible to provide them in a corresponding way at the rotor. Instead of sensors which measure the vibrations and the distance according to the reluctance method, respectively, it is also possible to use other sensors which measure other parameters, based upon which the alignment can be controlled.
FIG. 5 shows a flow diagram illustrating a first embodiment of the method according to the present invention. First, the position sensors are calibrated, at 501 , which position sensors are of the type described in connection with FIG. 1 , by pushing the position sensors out from the refining surface of the stator and moving them into contact with the refining surface of the rotor. Thereafter, a non-contact measurement of the distance between the refining surfaces at each measurement position according to the reluctance method is performed, at 502 , at three different measurement positions in the region of the refining gap and the refining surfaces by means of three position sensors positioned at different measurement positions, where each position sensor measures the reluctance in a circuit in which at least the refining surface of the rotor and the refining gap are included. The measurement of the distance is performed substantially along one and the same diameter of the refining surface of one of the refining discs. After this, the signals/measurement results from the position sensors are processed, at 503 . The measurement results are analysed, at 504 , which analysis comprises comparison of the measurement results with each other. The refining surface of the stator is adjusted based on this comparison in step 504 until substantially the same measurement results are obtained at all measurement positions, whereby correct alignment between the refining surfaces is attained. Thereafter, this process is preformed recurrently during the operation of the refining apparatus.
FIG. 6 shows a flow diagram illustrating a second embodiment of the method according to the present invention. First, the vibrations at four different measurement positions in the region of the refining gap and the refining discs are measured, at 601 , by measuring the amplitude and frequency of the vibrations, and this is performed by means of four accelerometers positioned at different measurement positions. The measurement of the vibrations is performed in one and the same refining disc, advantageously, as close to the refining surface of the refining disc as possible. Advantageously, first the frequency is observed and the frequency determines which amplitude shall be the leading one. Thereafter, the signals/measurement results received from the accelerometers are filtered, at 602 , so that noise is filtered out. The filtered signals are sampled, at 603 , after which the sampled signals are analysed, at 604 , which analysis comprises comparison of the measurement results with each other. The refining surface of the stator is adjusted, at 605 , based on the comparison in step 604 until substantially the same measurement results are obtained at all measurement positions, whereby correct alignment between the refining surfaces is attained. Thereafter, this process is preformed recurrently during operation of the refining apparatus.
By “substantially equal” is meant that the measurement results from all measurement positions are within a common and such a limited range that a satisfactory high degree of alignment between the refining surfaces is attained.
Instead of measuring the vibrations and distances according the reluctance method, it is also possible to measure other parameters, based upon which the alignment can be controlled.
FIG. 7 shows a diagram showing the relation between the vibration level of the stator and changes in refining gap of a refiner, where the y-axis shows the vibration level in the stator at a measurement position, and the x-axis shows the position of the rotor.
Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. | Methods and apparatus controlling the alignment between refining surfaces of opposite refining discs are disclosed which are relatively rotatable and which are incorporated in a refiner for disintegrating and refining lignocellulose-containing material in a refining gap between the refining surfaces. The disclosed method includes positioning at least three sensors at least three measurement positions, measuring the vibrations at each of the measurement positions during refiner operation, and comparing each of the measured vibrations at each of the measurement positions with each other. The apparatus disclosed includes at least three sensors disposed in at least three predetermined measurement positions, each of the sensors comprising a vibration sensor disposed on a refining disc for measuring the vibrations at the measurement positions whereby measuring can take place during operation of the refiner and a comparator for comparing the measurements of the measurement positions to provide a comparison therebetween. | 3 |
PRIORITY CLAIM
This application claims priority to U.S. Provisional Patent Application Ser. No. 61/699,362, filed Sep. 11, 2012, and entitled “Efficient Payload Reassembly,” the disclosure of which is incorporated by reference herein in its entirety and made part hereof.
FIELD
Aspects of the disclosure pertain to the field of communication systems.
BACKGROUND
In a communication system, one or more transmitters transmit over a shared medium towards a receiving station. The shared medium could include multiple channels, allowing several transmitters to simultaneously transmit towards the receiving station. At the receiving station, a plurality of receivers is used for receiving the transmissions.
A transmitter could segment a payload to several fragments and transmit each fragment towards the receiving station in a separate transmission. Different fragments of the payload could be transmitted over different channels within the shared medium and received by different receivers at the receiving station. Each fragment includes an identifier of the transmitter to allow the receiving station to distinguish between fragments and payloads of different transmitters.
To protect the integrity of the payload, the transmitter computes a Cyclic Redundancy Check (CRC) code for the payload and attaches the computed code to the first fragment of the payload. After receiving all the fragments of the payload (via the plurality of receivers), the receiving station rebuilds (reassembles) the payload from the fragments and validates the content of the payload by computing the CRC code for the rebuilt payload and comparing it with the CRC code which the transmitter attached to the first fragment.
However, before the receiving station can rebuild the payload from the received fragments, the receiving station needs to determine that all the fragments of the payload were received. Such determining is often based on including a sequence number in each fragment and an additional total fragment count in the first fragment. Unfortunately, the fragment numbering information is overhead which reduces the efficiency of the communication system. Alternatively, the receiving station can determine that the last fragment of the payload was received if a predefined interval has passed from the time of receiving the last fragment without receiving additional fragments for the payload. However, this alternative introduces latency to the communication system in addition to being vulnerable to errors. The receiving station could decide that all fragments were received while in fact one or more additional fragments are delayed (for example due to high load on the shared medium).
SUMMARY
The following presents a simplified summary in order to provide a basic understanding of some aspects of the disclosure. The summary is not an extensive overview of the disclosure. It is neither intended to identify key or critical elements of the disclosure nor to delineate the scope of the disclosure. The following summary merely presents some aspects of the disclosure in a simplified form as a prelude to the description below.
Aspects of the disclosure are directed to methods for rebuilding (reassembling) a payload from one or more fragments of the payload and for validating the integrity of the data included in the rebuilt payload. In some embodiments, reception of the last fragment of the payload may be determined without requiring any of the fragments to be numbered and without waiting for a next fragment for any period of time. In some embodiments, said validation may be included in said determining, wherein the amount of calculations needed for said validation and/or determining may be in about the same order of magnitude as the calculations required for computing a CRC code for the whole payload.
BRIEF DESCRIPTION OF THE DRAWINGS
Having thus described the disclosure in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:
FIG. 1 shows an example of a communication system in accordance with aspects of the disclosure.
FIG. 2 shows a flow chart of an exemplary reassembly algorithm in accordance with aspects of the disclosure.
FIG. 3 shows a diagram of an exemplary payload and its fragments in accordance with aspects of the disclosure.
DETAILED DESCRIPTION
Referring to FIG. 1 , a communication system 100 may comprise one or more transmitter(s) 120 a - n , a shared medium 110 and a receiving station 130 . The one or more transmitter(s) 120 a - n may be configured to transmit over shared medium 110 towards receiving station 130 , wherein several transmitters of the one or more transmitter(s) 120 a - n may simultaneously transmit towards receiving station 130 over a plurality of channels that may be included in the shared medium 110 . Receiving station 130 may comprise a plurality of receivers 131 a - k , for at least the purpose of receiving transmissions from the one or more transmitter(s) 120 a - n , and a re-assembler 132 .
A transmitter, for example transmitter 120 a , may be configured to segment a payload to one or more fragments and transmit each of the one or more fragments towards receiving station 130 , e.g. to transmit each fragment in a separate transmission. Transmitter 120 a may be further configured to compute a Cyclic Redundancy Check (CRC) code for the payload and to transmit the computed CRC code together with the first fragment of the payload, e.g. in the same transmission.
Transmitter 120 a may be configured to transmit the fragments sequentially via medium 110 , e.g. one after the other in accordance with their order within the respective payload. As medium 110 may inflict about the same latency on all fragments, the fragments may arrive at receiving station 130 at the same order as they may be transmitted (e.g. the first fragment transmitted may arrive first, the second fragment transmitted may arrive second, and so on). This order may be further maintained regardless of whether the fragments are received by a single receiver or by several receivers (e.g. each one of the several receivers may receive only some of the fragments).
Receiving station 130 may be configured to receive (e.g. using receivers 131 a - k ) one or more fragments of a payload, to rebuild (reassemble) the payload from the received one or more fragments and to validate the content of the payload (e.g. at re-assembler 132 ). In some embodiments, said validation may be performed by computing a CRC code for the rebuilt payload and comparing it with a CRC code which the transmitter of said one or more fragments may have attached to the first fragment of the payload.
Receivers 131 a - k of receiving station 130 may be configured to receive one or more fragments of a payload. In some embodiments, each receiver of receivers 131 a - k may be configured to maintain a synchronized clock, so that all receives 131 a - k may have about the same clock value at the same time. Each receiver of receivers 131 a - k may be configured upon receiving a fragment of a payload to create a timestamp based on said synchronized clock, to attach the timestamp to the received fragment (e.g. for at least the purpose of indicating a reception time for the received fragment) and to forward the time-stamped received fragment to re-assembler 132 . In some embodiments, the process of creating a timestamp and attaching it to a received fragment may be implemented in hardware, for example in order to have this process take about the same time in each of the receivers 131 a - k.
Re-assembler 132 may be configured to simultaneously reassemble and validate multiple payloads, for example payloads simultaneously transmitted by multiple transmitters out of the one or more transmitter(s) 120 a - n . Nevertheless, re-assembler 132 may be configured to reassemble and/or validate each payload independently of reassembling and/or validating any other payloads. In some embodiments, each fragment may include an identifier of a respective transmitter and/or an identifier of a respective stream of payloads, thus allowing re-assembler 132 to distinguish, for example, between fragments of different payload streams and/or between fragments transmitted by different transmitters.
Referring to FIG. 2 , re-assembler 132 may be configured upon receiving a fragment (step 210 ) to determine whether this fragment is a leading fragment of a payload or a non-leading fragment (step 220 ), wherein a leading fragment may be the first fragment of the payload and may include a CRC code for the payload (e.g. as may be calculated by the respective transmitter), and wherein a non-leading fragment may be any fragment of the payload other than the first fragment of the payload. If the received fragment is a leading fragment of a payload, re-assembler 132 may be configured to start a new ordered list of fragments (step 221 ) and to place the received leading fragment at the head of that list (step 222 ). If the received fragment is a non-leading fragment of a payload, re-assembler 132 may be configured to try associating the received non-leading fragment with an already existing list of fragments (for example based on a transmitter and/or a stream identifier(s) included in each fragment) and to add the non-leading fragment to the respective list of fragments, if such list exists (steps 230 , 240 and 250 ). If the received fragment is a non-leading fragment and it may not be associated with any existing list of fragments, re-assembler 132 may be configured to start a new ordered list of fragments (step 221 ) and place the received non-leading fragment at the head of the newly started list (step 222 ). The latter scenario may occur for example due to re-assembler 132 receiving a non-leading fragment from receivers 131 a - k prior to receiving the respective leading fragment as described herein.
Although the received fragments may be received at receive station 130 in the same order as they were transmitted, and time-stamped by receivers 131 a - k in the same order as the order of transmission, the time-stamped received fragments may be forwarded by receivers 131 a - k to re-assembler 132 in a different order, for example due to forwarding the time-stamped fragments over a shared medium (e.g. LAN 133 ), or due to different processing durations in different receivers. Thus, re-assembler 132 may be configured upon receiving fragments of a payload to order them in accordance with their attached timestamps (step 250 ), for at least the purpose of ordering the fragments in accordance with their order of transmission, which may correspond to their order within the payload. Re-assembler 132 may be configured to add a non-leading fragment to an existing list of fragments in accordance with the timestamp attached to the non-leading fragment and the one or more timestamps attached to the one or more fragments already included in the list of fragments respectively (step 250 ), so that the list may remain sorted in accordance with the reception time of the fragments after the non-leading fragment has been added.
After placing a received fragment in an ordered list of fragments, re-assembler 132 may be configured (step 260 ) to determine whether the respective list of fragments includes a leading fragment (e.g. whether the first fragment in the list is a leading fragment). If the respective list of fragments does not include a leading fragment, re-assembler 132 may be configured to wait for additional fragments to be received (step 261 ). However, if the respective list of fragments includes a leading fragment, re-assembler 132 may be configured to calculate a CRC code for a payload reassembled from all the fragments currently in the list (step 270 ) and to compare the calculated CRC code with the CRC code included in the leading fragment (step 280 ). If the calculated CRC code is the same as the CRC code included in the leading fragment, re-assembler 132 may be configured to determine that all the fragments of the payload were received and that the payload may be successfully reassembled. Upon so determining, re-assembler 132 may be configured to (step 281 ) terminate the reassembly process for this payload and, in some embodiments, may forward the re-assembled payload to a higher-layer function that may be included in receiving station 130 (not shown in FIG. 1 ). However, if the calculated CRC code is different than the CRC code included in the leading fragment, re-assembler 132 may be configured to determine that at least one more fragment of the respective payload may yet to be received and to wait for the at least one more fragment (step 261 ). Re-assembler 132 may be further configured upon determining that a preconfigured interval may have elapsed since the reception of a last fragment of a payload (step 262 ), to determine that the payload may not be successfully reassembled and to discard all the received fragments corresponding to that payload (step 263 ). Such a scenario may occur, for example, if one or more fragments were not received by receivers 131 a - k (e.g. due to interferences on medium 110 ), or if the fragments may have been received with errors, which may cause the calculated CRC code for the reassembled payload to be different from a CRC code which may be included in the leading fragment of the payload and which may have been calculated by the transmitter for the payload prior to transmitting it (e.g. as fragments).
In some embodiments, re-assembler 132 may be configured to calculate the CRC code for a payload comprised of one or more fragments (e.g. as in step 270 in FIG. 2 ) using one or more CRC codes previously calculated for each of the one or more fragments respectively. Re-assembler 132 may receive fragments of a payload from multiple receivers, reassemble the payload and use such pre-calculated partial CRC codes for at least the purpose of validating the payload (e.g. verifying that all the fragments of the payload were correctly received) with a minimum amount of computation, while perhaps introducing a minimum latency and without needing the fragments to be numbered.
In some embodiments, re-assembler 132 may be configured to calculate a CRC code for each received fragment, for example, upon receiving the fragment (e.g. step 210 of FIG. 2 ), or upon adding the fragment to a list of fragments (e.g. steps 221 and/or 250 ), or at any other time prior to calculating the CRC code for the reassembled payload (e.g. step 270 ). In some embodiments, re-assembler 132 may be configured to receive each fragment together with the CRC code for that fragment attached to the fragment. For example, each receiver 131 a - k may be configured to calculate a CRC code for each received fragment, to attach the calculated CRC code to the received fragment (e.g. in addition to attaching a timestamp) and to forward the time-stamped received fragment with the calculated CRC code to re-assembler 132 . In some embodiments, re-assembler 132 may be configured to determine if a received fragment has a CRC code attached to it and to calculate a CRC code for the received fragment if a CRC code is not attached to the received fragment.
Let M represent a payload, which may be transmitted in n fragments denoted M 0 to M n-1 , wherein M 0 may represent the fragment containing the least significant bits of payload M and M n-1 may represent the fragment containing the most significant bits of payload M. In some embodiments, fragment M 0 may also be the leading fragment and/or the first fragment to be transmitted. In addition, let CRC(M i ) represent the CRC code for fragment M i (for each 0≦i≦n−1). Thus, re-assembler 132 may be configured to calculate a CRC code for the entire payload M (e.g. CRC(M)) using CRC codes corresponding to fragments M 0 to M m-1 (e.g. CRC(M 0 ) to CRC(M n-1 ), respectively) as shown herein.
CRC calculation may be based on arithmetic of polynomials over the binary field GF(2), wherein GF(2) is the Galois Field of two elements. Thus, in the following description the asterisk sign (*) may represent polynomials multiplication over GF(2), and the plus sign (+) may represent polynomials addition over GF(2). In addition, bit strings may be represented as polynomials over GF(2). For example, the bit string “1011” may be represented using the polynomial x 3 +x+1.
A CRC code may be calculated using a polynomial g(x) of a degree r (e.g. having r+1 coefficients). For example, in the case of CRC-32, the degree of the polynomial g(x) is 32 (r=32). In addition, a CRC calculation may be defined and/or implemented in terms of a linear feedback shift register (LFSR) of a length r. There may be two variants for CRC calculation, which may differ by the initialization of the LFSR prior to passing the bit-string for which CRC should be calculated through the LFSR. In one variant, the LFSR may be initialized with all its bits set to 0 (referred to herein as 0-initialized, for example 0x0000 for CRC-32, wherein 0x0000 is the hexadecimal notation for a string of 32 bits all set to 0). In the other variant, the LFSR may be initialized with all its bits set to 1 (referred to herein as 1-initialized, for example 0xFFFF for CRC-32, wherein 0xFFFF is the hexadecimal notation for a string of 32 bits all set to 1).
Let CRC 0 (M) represent the 0-initialized CRC code for payload M. CRC 0 (M) may be mathematically defined as follows (Eq. 1):
CRC 0 ( M )=[ M ( x )* x r ] mod g ( x )
Wherein M(x) may be the polynomial representation of payload M, g(x) may be the polynomial that may be used for calculating the CRC, r may be the degree of g(x) and mod may be the modular polynomial division.
Let CRC 1 (M) represent the 1-initialized CRC code for a payload M after flipping (e.g. changing a 1 to a 0, or a 0 to 1) the r most significant bits of payload M before the CRC calculation. CRC 1 (M) may be mathematically defined as follows (Eq. 2):
CRC 1 ( M )={[ M ( x )+ F ( x )* x (q-r) ]*x r } mod g ( x )
Wherein M(x) may be the polynomial representation of payload M, g(x) may be the polynomial that may be used for calculating the CRC, r may be the degree of g(x), q−1 may be the degree of M(x), mod may be the modular polynomial division, and F(x) may be a polynomial representing r bits all set to 1 (e.g. of degree r−1).
It may be noted that though many publications regarding CRC calculation may discuss the 0-initialized variant (CRC 0 ), it may be the 1-initialized variant (i.e. CRC 1 ) which may be more commonly used in many communication systems. Thus, the following disclosure may present a method for CRC calculation (e.g. for payload M) in accordance with the 1-initialized variant (CRC 1 ). However, as presented herein, calculation of a 1-initialized CRC (e.g. for a payload M) in an efficient manner may be based on calculations in accordance with the 0-initialized variant (CRC 0 ).
In order to simplify the description of the algorithm, the following description is based on an example payload M as shown in FIG. 3 (e.g. payload M 300 ), wherein in this example payload M may be transmitted in 4 fragments (e.g. n=4), M 0 to M 3 ( 301 to 304 respectively). Nevertheless, the algorithm may be applied to any payload with any number of fragments without departing from the scope of this disclosure.
Let M(x) be the polynomial representation of payload (bit string) M, and let M i (x) be the polynomial representation of fragment (bit string) M i of payload M. Thus, the relation between the polynomial representation of payload M and the polynomial representations of all the fragments of payload M may be as follows (Eq. 3):
M ( x )= M 3 ( x )* x k3 +M 2 ( x )* x k2 +M 1 ( x )* x k1 +M 0 ( x )
Wherein k3 may be the offset of fragment M 3 within payload M ( 314 ) (e.g. the total number of bits in fragments M 2 , M 1 and M 0 ), k2 may be the offset of fragment M 2 within payload M ( 313 ) (e.g. the total number of bits in fragments M 1 and M 0 ), and k1 may be the offset of fragment M 1 within payload M ( 312 ) (e.g. the number of bits in fragment M 0 ). Let q represent the total number of bits in payload M ( 320 ) (e.g. over which a CRC code may be calculated).
Given CRC 0 (M i ) for each fragment M i of payload M, CRC 0 (M) may be calculated (e.g. in accordance with Eq. 1 and Eq. 3) as follows (Eq. 4):
CRC
0
(
M
)
=
[
M
(
x
)
*
x
r
]
mod
g
(
x
)
=
=
{
[
M
3
(
x
)
*
x
k
3
+
M
2
(
x
)
*
x
k
2
+
M
1
(
x
)
*
x
k
1
+
M
0
(
x
)
]
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x
r
}
mod
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(
x
)
=
=
{
[
[
M
3
(
x
)
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x
r
]
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(
x
)
]
*
[
x
k
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mod
g
(
x
)
]
+
[
[
M
2
(
x
)
*
x
r
]
mod
g
(
x
)
]
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[
x
k
2
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(
x
)
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+
[
[
M
1
(
x
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x
r
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g
(
x
)
]
*
[
x
k
1
mod
g
(
x
)
]
+
[
[
M
0
(
x
)
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x
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(
x
)
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(
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=
=
{
CRC
0
(
M
3
)
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[
x
k
3
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(
x
)
]
+
CRC
0
(
M
2
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x
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2
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(
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)
]
+
CRC
0
(
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1
)
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x
k
1
mod
g
(
x
)
]
+
CRC
0
(
M
1
)
]
}
mod
g
(
x
)
The second step in Eq. 4 may follow from Eq. 3. The third and the fourth steps in Eq. 4 may be derived from the second step using two valid principles for polynomial arithmetic: the linearity of modular polynomial division (e.g. (a+b) mod c=(a mod c)+(b mod c)), and the fact that a modular multiplication can be preceded by a modular reduction of each factor first (e.g. (a*b) mod c=((a mod c)*(b mod c)) mod c).
It may be noted that the terms [x ki mod g(x)] may be independent of payload M. On the other hand, the number of such terms may depend on the number of fragments that may be used for transmitting payload M. In some embodiments, for at least the purpose of reducing the amount of calculations in real-time or substantially in real-time, the terms [x ki mod g(x)] may be pre-calculated and stored in a memory (for example in the form of a look-up table) for any number of fragments, for example in accordance with a maximum size of a payload in a communication system and/or a maximum number of fragments that a transmitter may use in segmenting a payload. Thus, given a 0-initialized CRC code for each fragment M i of payload M (e.g. CRC 0 (M i )) and said pre-calculated values of the terms [x ki mod g(x)], calculation of a 0-initialized CRC code for payload M (e.g. CRC 0 (M)) may comprise only low-complexity operations on arguments of r bits only, wherein the number of such operations may be in linear proportion to the number of fragments corresponding to payload M (e.g. for n fragments, n−1 multiplications, n−1 additions and one modular polynomial division). It may be noted that r may be a constant, independent of the number of bits in payload M, and in most cases significantly smaller than the length of payload M (e.g. r<<q) or of any of its fragments.
Considering the third step in Eq. 4, the following may be derived (Eq. 5):
CRC
0
(
M
)
=
[
M
(
x
)
*
x
r
]
mod
g
(
x
)
=
=
{
[
[
M
3
(
x
)
*
x
r
]
mod
g
(
x
)
]
*
[
x
k
3
mod
g
(
x
)
]
+
[
[
M
2
(
x
)
*
x
r
]
mod
g
(
x
)
]
*
[
x
k
2
mod
g
(
x
)
]
+
[
[
M
1
(
x
)
*
x
r
]
mod
g
(
x
)
]
*
[
x
k
1
mod
g
(
x
)
]
+
[
[
M
0
(
x
)
*
x
r
]
mod
g
(
x
)
]
}
mod
g
(
x
)
=
[
{
[
[
M
3
(
x
)
*
x
r
]
mod
g
(
x
)
]
*
[
[
x
k
3
-
2
·
r
*
x
r
]
mod
g
(
x
)
]
+
[
[
M
2
(
x
)
*
x
r
]
mod
g
(
x
)
]
*
[
[
x
k
2
-
2
·
r
*
x
r
]
mod
g
(
x
)
]
+
[
[
M
1
(
x
)
*
x
r
]
mod
g
(
x
)
]
*
[
[
x
k
1
-
2
·
r
*
x
r
]
mod
g
(
x
)
]
+
}
*
x
r
]
mod
g
(
x
)
+
[
[
M
0
(
x
)
*
x
r
]
mod
g
(
x
)
=
CRC
0
{
CRC
0
(
M
3
)
*
CRC
0
(
x
k
3
-
2
·
r
)
+
CRC
0
(
M
2
)
*
CRC
0
(
x
k
2
-
2
·
r
)
+
CRC
0
(
M
1
)
*
CRC
0
(
x
k
1
-
2
·
r
)
}
+
CRC
0
(
M
0
)
The second step of Eq. 5 may be the same as the third step of Eq. 4. The third step of Eq. 5 may be derived from the second step of Eq. 5 by excluding for the first three addition elements a common factor x r for all elements together and another x r factor for each x ki sub-element while compensating for these exclusions by reducing the degree of x ki by 2r (e.g. under the assumption that ki>2r, or in other words that the length of at least the first fragment (M 0 ) may be at least twice as long as the degree of the CRC polynomial g(x), as the above condition may have to be fulfilled for k1 as well, wherein k1 may be equal to the number of bits in fragment M 0 ). It may be noted that the third step of Eq. 5 may have structured the entire expression in a form, which may allow calculation of a 0-initialized CRC code for payload M (e.g. CRC 0 (M)) using a pre-calculated 0-initialized CRC code for each of the fragments of payload M (e.g. CRC 0 (M i )) and using a pre-calculated 0-initialized CRC code for each of the polynomials x ki-2r (e.g. CRC 0 (x ki-2r ), wherein each polynomial x ki-2r may represent a bit string of ki−2r+1 bits in which the most significant bit is set to 1 and all the other bits are set to 0), as shown in the fourth step of Eq. 5. The fourth step of Eq. 5 may show that both the pre-calculations (e.g. per fragment) and the final calculation (e.g. for payload M) may be performed as 0-initialized CRC calculations (e.g. CRC 0 ) or operations. The fourth step of Eq. 5 may further show that if the 0-initialized CRC code for each of the n fragments included in payload M (e.g. CRC 0 (M i ) for each i=0 . . . n−1) and the 0-initialized CRC codes for the n−1 polynomials x ki-2r (e.g. CRC 0 (x ki-2r ) for each i=1 . . . n−1) are pre-calculated, the final calculation of the 0-initialized CRC code for the entire payload M (e.g. CRC 0 (M)) may comprise only n−1 look-ups (e.g. for CRC 0 (x ki-2r )), n−1 multiplications of low-degree polynomials (r bits each), 3 exclusive-or (XOR) operation (e.g. addition of 2r bit-long strings) and a single 0-initialized CRC calculation on a 2r bit-long string (e.g. which may be an operation performed using a constant amount of processing independent of the length of payload M). Thus the fourth step of Eq. 5 may be used in some embodiments for simplifying any of a hardware implementation or a software implementation, as a single circuit design (e.g. of one or more instances) or a single procedure for calculating a 0-initialized CRC code for a bit string may be utilized for performing nearly all the necessary calculations.
Having described methods for calculating a 0-initialized CRC code for a payload M using 0-initialized CRC codes that may be pre-calculated for each fragment included in the payload and for predefined bit strings, the following may describe a method for calculating a 1-initialized CRC code for a payload M in a similar manner.
Considering Eq. 2 and Eq. 1, the following may be derived (Eq. 6):
CRC
1
(
M
)
=
{
[
M
(
x
)
+
F
(
x
)
*
x
(
q
-
r
)
]
*
x
r
}
mod
g
(
x
)
=
[
M
(
x
)
*
x
r
]
mod
g
(
x
)
+
[
F
(
x
)
*
x
q
-
r
*
x
r
]
mod
g
(
x
)
=
CRC
0
(
M
)
+
CRC
1
(
Z
q
)
Wherein F(x) may be a polynomial representing r bits all set to 1, and Z q may be a bit string of length q (e.g. the same length of payload M) in which all bits may be set to 0. Since Z q may be a constant bit string for any given size of payload M (q), a 1-initialized CRC code for Z q (e.g. CRC 1 (Z q )) may be pre-calculated and stored in a memory for any applicable value of q.
By combining the last step of Eq. 5 (e.g. for calculating a 0-initialized CRC code for payload M) into Eq. 6, the following may be derived (Eq. 7):
CRC
1
(
M
)
=
CRC
0
(
M
)
+
CRC
1
(
Z
q
)
=
CRC
0
{
CRC
0
(
M
3
)
*
CRC
0
(
x
k
3
-
2
·
r
)
+
CRC
0
(
M
2
)
*
CRC
0
(
x
k
2
-
2
·
r
)
+
CRC
0
(
M
1
)
*
CRC
0
(
x
k
1
-
2
·
r
)
}
+
CRC
0
(
M
0
)
+
CRC
1
(
Z
q
)
Putting Eq. 7 in a more general form (Eq. 8):
CRC
1
(
M
)
=
CRC
0
{
CRC
0
(
M
n
-
1
)
*
CRC
0
(
x
k
n
-
1
-
2
·
r
)
+
…
+
CRC
0
(
M
1
)
*
CRC
0
(
x
k
1
-
2
·
r
)
}
+
CRC
0
(
M
0
)
+
CRC
1
(
Z
q
)
Wherein M may represent the entire payload, M 0 to M n-1 may represent the n fragments of the payload, ki may represent the offset (e.g. in bits) of a fragment M i within the payload (i=1 . . . n−1), r may represent the size of the CRC polynomial (e.g. r=32 for CRC-32), Zq may represent a bit string of the same length as the payload in which all bits are set to 0, CRC 0 may represent a 0-initialized CRC code, and CRC 1 may represent a 1-initialized CRC code.
Thus, re-assembler 132 may be configured to calculate a (1-initialized) CRC code for a payload M (e.g. CRC 1 (M)), the payload M reassembled from n fragments (e.g. M 0 to M n-1 ), using a method comprising:
a) Calculating or receiving a 0-initialized CRC code for each received fragment (e.g. CRC 0 (M i ), i=0 . . . n−1). b) Using pre-calculated 0-initialized CRC codes for the n−1 polynomials x ki-2r (e.g. CRC 0 (x ki-2r ), i=1 . . . n−1), wherein the polynomial x ki-2r may represent a bit string of ki−2r+1 bits in which the most significant bit is set to 1 and all the other (ki−2r) bits are set to 0. c) Calculating n−1 multiplications, wherein each multiplication may be of two polynomials of length r (e.g. S i =CRC 0 (M i )*CRC 0 (x ki-2r ), i=1 . . . n−1) and the multiplication may be of length 2 r bits, wherein r may be the degree of the CRC polynomial.
For example, in embodiments where CRC-32 may be used, a multiplication of 64 bits may be calculated by 16 sub-multiplications of 8-bit polynomials (e.g. that may be calculated using a 256 by 256 table) followed by shifts and XOR operations on the sub-multiplications.
d) Performing (2r bits wide) XOR operation over all n−1 multiplications calculated in step c) (e.g. S n-1 + . . . +S 1 ). e) Calculating the 0-initialized CRC code for the result of the XOR operation of step d) (e.g. CRC 0 (S n-1 + . . . +S 1 )).
As previously described, re-assembler 132 may be configured, upon receiving each additional fragment of the payload, to calculate a CRC code for a reassembly of all the fragments of the payload already received. It may be noted that if the result of the XOR operation of step d) is stored in memory (e.g. S j + . . . +S 1 for fragments M 1 to M j ), upon receiving a next fragment (e.g. M j+i ) the 0-initialized CRC calculation for a reassembly of all the fragments of the payload already received (e.g. including the next fragment M j+i ) may be performed by simply calculating the respective multiplication for the next fragment (e.g. S j+i ), performing a 2r bit-long XOR operation between the previously stored result and the calculated multiplication of the next segment (e.g. S j+i +(S j + . . . +S i )), recalculating the 0-initialized CRC code on the updated 2r bit-long XOR result (e.g. CRC 0 (S j+1 + . . . +S 1 )) and performing the rest of the steps described herein. The above shortcut may be applicable if the received next fragment (e.g. M j+1 ) does not precede any of the previously received fragments (e.g. if it is added at the end of a list of fragments (e.g. as shown in step 250 of FIG. 2 )). In case the next fragment arrives out-of-order, all the multiplications may have to be recalculated, for example due to changes in the respective offsets of one or more of the previously received fragments.
f) Performing XOR operation on the result of step e) with the previously calculated or received 0-initialized CRC code for the first fragment (e.g. CRC 0 (S n-1 + . . . +S 1 )+CRC 0 (M 0 )). g) Performing a XOR operation on the result of step f) with a pre-calculated 1-initialized CRC code for a bit steam of the same length of payload M in which all bits may be set to 0 (e.g. CRC 0 (S n-1 + . . . +S 1 )+CRC 0 (M 0 )+CRC 1 (Z q )).
In some embodiments, communication system 100 may be a satellite communication system comprising one or more terminals (e.g. transmitter(s) 120 a - n ) configured to transmit over a satellite (e.g. medium 110 ) towards a central hub (e.g. receiving station 130 ), wherein several terminals may simultaneously transmit towards the hub using a plurality of channels over the satellite.
At least one terminal of the one or more terminals may be configured to segment a payload to be transmitted towards the hub (e.g. an Internet Protocol (IP) packet or any other type of packet or a frame that may be transmitted from a terminal to the hub) to one or more fragments, and to transmit the one or more fragments towards the hub using one or more separate transmissions, for example burst transmissions over a Time Division Multiple Access (TDMA) or a Multi-Frequency Time Division Multiple Access (MF-TDMA) return channel. The at least one terminal may be further configured to compute a CRC code for the payload and to transmit the computed CRC code together with the first fragment of the payload, e.g. in the same transmission.
The hub may comprise a plurality of receivers (e.g. receivers 131 a - k ) configured to receive transmissions from the one or more terminals, said transmissions containing one or more fragments of one or more payloads, and at least one processing element (e.g. re-assembler 132 ) configured to re-assemble a payload from one or more received fragments of the payload and to validate the content of the payload. Said plurality of receivers may be configured to maintain a synchronized clock and to timestamp received fragments in accordance with said clock for at least the purpose of allowing the at least one processing element to order and/or reorder received fragments in accordance with their transmission time.
The at least one processing element may be further configured to calculate a CRC code for a payload using one or more CRC codes previously calculated for one or more fragments of the payload respectively, wherein the CRC codes for the one or more fragments may be either calculated by the processing element or received by the processing element with the fragments (e.g. the receivers may be configured to calculate a CRC code for each received fragment and to attach the calculated CRC code to the received fragment upon forwarding it to the processing element). The at least one processing element may be further configured upon receiving each fragment to perform said calculation on all the already received fragments and to use the calculated CRC code for at least the purpose of validating the payload (e.g. verifying that all the fragments of the payload were correctly received) with a minimum amount of computation, while perhaps introducing a minimum latency and without needing the fragments to be numbered.
In some embodiments, the at least one processing element may be configured to calculate a CRC code for a payload as a 1-initialized CRC code in accordance with the formula (Eq. 9):
CRC
1
(
M
)
=
CRC
0
{
CRC
0
(
M
n
-
1
)
*
CRC
0
(
x
k
n
-
1
-
2
·
r
)
+
…
+
CRC
0
(
M
1
)
*
CRC
0
(
x
k
1
-
2
·
r
)
}
+
CRC
0
(
M
0
)
+
CRC
1
(
Z
q
)
Wherein M may represent the entire payload, M 0 to M n-1 may represent the n fragments of the payload, ki may represent the offset (e.g. in bits) of a fragment M i within the payload (i=1 . . . n−1), r may represent the size of the CRC polynomial (e.g. r=32 for CRC-32), Zq may represent a bit string of the same length as the payload in which all bits are set to 0, CRC 0 may represent a 0-initialized CRC code, and CRC 1 may represent a 1-initialized CRC code.
Various aspects of the disclosure may be embodied as one or more methods, systems, apparatuses (e.g., components of a satellite communication network), and/or computer program products. Accordingly, those aspects may take the form of an entirely hardware embodiment, an entirely software embodiment, an entirely firmware embodiment, or an embodiment combining firmware, software, and/or hardware aspects. Furthermore, such aspects may take the form of a computer program product stored by one or more computer-readable storage media having computer-readable program code, or instructions, embodied in or on the storage media. Any suitable computer readable storage media may be utilized, including hard disks, CD-ROMs, optical storage devices, magnetic storage devices, and/or any combination thereof. In some embodiments, one or more computer readable media storing instructions may be used. The instructions, when executed, may cause one or more apparatuses to perform one or more acts described herein. The one or more computer readable media may comprise transitory and/or non-transitory media. In addition, various signals representing data or events as described herein may be transferred between a source and a destination in the form of electromagnetic waves traveling through signal-conducting media such as metal wires, optical fibers, and/or wireless transmission media (e.g., air and/or space).
Modifications may be made to the various embodiments described herein by those skilled in the art. For example, each of the elements of the aforementioned embodiments may be utilized alone or in combination or sub-combination with elements of the other embodiments. It will also be appreciated and understood that modifications may be made without departing from the true spirit and scope of the present disclosure. The description is thus to be regarded as illustrative instead of restrictive on the present disclosure. | A communication system comprises one or more transmitters and a receiving station. A transmitter segments a payload to be transmitted into multiple fragments and transmits each fragment of the payload in a different transmission. The receiving station receives the fragments, reassembles the payload from the received fragments and validates the integrity of the payload. Methods are presented for efficiently rebuilding a payload from fragments of the payload and for validating the integrity of the payload. | 7 |
This is a continuation of copending application Ser. No. 07/718,388, filed on Jun. 20, 1991, now U.S. Pat. No. 5,154,095.
THE FIELD OF THE INVENTION
The present invention relates to bicycle handlebars in which there is a forward extension of the bar for use when the rider wishes to assume an aerodynamic profile. Conventionally in such handlebars provision is made for the rider to rest his arms upon arm rest supports which are mounted on the handlebar in a position to support the underside of the rider's arms. When a rider does not wish to assume an aerodynamic profile, for example, when climbing, the rider normally will grip the handlebar in what is known as a "climbing" position. The present invention provides a means for mounting the arm rests so that they do not interfere with the hand position used by the rider when in a climbing mode.
DESCRIPTION OF THE RELATED ART
U.S. Pat. No. 4,878,397 shows a bicycle handlebar construction in which there is an auxiliary handlebar in the form of a forward extension which provides hand gripping portions for the rider when assuming an aerodynamic profile. This patent also shows arm rests for the rider when in that profile. The arm rests are mounted on the bicycle at approximately the area where the rider would grip the bar when in a climbing mode. The present invention positions and locates the arm rests to insure that they will not interfere with the rider's normal use of the handlebar.
SUMMARY OF THE INVENTION
The present invention relates to bicycle handlebars and in particular to the construction and mounting of arm rests for use by a rider when assuming an aerodynamic profile.
A primary purpose of the invention is a bicycle handlebar having a forward extension for use by the rider in assuming an aerodynamic profile and arm rests which are mounted for use by the rider when assuming such profile, but are so located and constructed as to not interfere with the rider's normal use of other portions of the handlebar.
Another purpose is a bicycle handlebar as described in which the arm rests are biased to a normally upward position.
Another purpose is a bicycle handlebar as described utilizing arm rests which have provision for variable location to suit the needs of a particular rider.
Other purposes will appear in the ensuing specification, drawings and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is illustrated diagrammatically in the following drawings wherein:
FIG. 1 is a top plan view of the bicycle handlebar disclosed herein,
FIG. 2 is a rear view of the bicycle handlebar of FIG. 1,
FIG. 3 is a side view of the bicycle handlebar,
FIG. 4 is an enlarged partial section illustrating the support bracket for the arm rest of FIGS. 1, 2 and 3,
FIG. 5 is a section along plane 5--5 of FIG. 4,
FIG. 6 is a top view of the arm rest support bracket with portions removed,
FIG. 7 is a top view of the arm rest support bracket,
FIG. 8 is a top plan view of a further embodiment of bicycle handlebar,
FIG. 9 is a rear view of the bicycle handlebar of FIG. 8,
FIG. 10 is a rear view of a further embodiment of bicycle handlebar,
FIG. 11 is a side view of the handlebar of FIG. 9,
FIG. 12 is an enlarged side view of the arm rest support bracket us in the FIGS. 8, 9, 10 and 11 handlebar,
FIG. 13 is a top view of the support bracket of FIG. 12,
FIG. 14 is an end view of the support bracket of FIGS. 12 and 13,
FIG. 15 is a top view of a further embodiment of bicycle handlebar, and
FIG. 16 a rear view of the bicycle handlebar of FIG. 15.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is specifically concerned with a bicycle handlebar which has a forward extension for use by the rider in assuming an aerodynamic profile. Such use normally requires an arm rest to support the rider in that profile. The present invention is more particularly concerned with the location, position and construction of the arm rest so as to not interfere with use of the handlebar by the rider when not in an aerodynamic profile.
In bicycle racing the rider normally assumes an aerodynamic profile, for example in a time trial, when the terrain is relatively flat and speed is the primary consideration. However, during the same race the rider may be required to cover substantial uphill terrain in which the rider will place his hands in what is known as the "climbing" position, generally adjacent and on either side of the center stem. The present invention is particularly concerned with the placement of the arm rests and the structure of the arm rests so that they do not interfere with the rider's hands when so gripping the handlebar.
In the embodiment of FIGS. 1-7, a main handlebar is indicated generally at 10 and includes a central, generally horizontal section 12 which is mounted in the bicycle center stem 14. On either side of the center section 12 are generally down-turned handlebar sections 16, each of which terminate in forwardly-extending sections 18. In the normal use of the bicycle the rider may grip the forwardly-extending sections 18 or, when in a climbing mode, may grip the center section 12 on either side of the stem 14.
Extending forwardly from the main handlebar 10 is an auxiliary handlebar indicated generally at 20 which has two parallel forwardly-extending tubular portions 22. At the forward end of sections 22 there are diverging handlebar sections 24 which, as illustrated in FIG. 3, may be slightly up-turned. Extending from the diverging and up-turned sections 24 are two in-turned sections 26 which, again as shown in FIG. 3, will extend upwardly at an angle somewhat greater than that for sections 24. The handlebar sections 26 are joined together in a curved section 28 which is at the forward end of the auxiliary handlebar 20. When a rider desires to assume an aerodynamic profile, generally his hands will grip the converging and upwardly-extending sections 26.
Arm rests are mounted on the central section 12 of the main handlebar 10 generally on opposite sides of stem 14. The arm rests are indicated generally at 30 and each includes an arm rest pad 32 mounted on an arm rest support bar 34. As particularly shown in FIG. 7, the support bar 34 may have a plurality of spaced openings 35, or an elongated opening which may be used to mount arm rest pads 32, thus providing for variant positioning of the arm rest support pads.
Each of the support bars 34 is pivotally mounted to an upper support bracket 36 which, in cooperation with a lower support bracket 38, provides the means for mounting the arm rests to the central section 12 of the handlebar. Screw fasteners or the like indicated at 40, and as shown in FIG. 4, connect the upper and lower brackets 36 and 38 together on the handlebar. The upper bracket 36 may have one or more spaced cantilever spring arms 42, each of which has an up-turned portion 44 biased against the underside of support bar 34. The spring arms 42 normally urge the support bars and thus the arm rests to the full line position in FIG. 5. The dotted line position of FIG. 5 represents a lowered position of the support bar and arm rest under the conditions when the rider is placing the weight of his arms and body on the arm rests. Normally, when the arm rests are not in use, they will be urged by springs 42 to the upper full-line position of FIG. 5.
The auxiliary handlebar 20 may be attached to handlebar 12 by the use of the arm rest support brackets. As particularly shown in FIG. 4, lower support bracket 38 has a socket 46 which receives one end of an extension 48 of auxiliary handlebar 20. A threaded fastener 50 may extend through a bore 52 in bracket 38 and provides a means for varying the relative position of sleeve 48 and the auxiliary handlebar 20 to thus vary the distance at which the auxiliary handlebar extends forwardly from main handlebar 10.
In the embodiment of FIGS. 8 and 9, the auxiliary handlebar and the main handlebar are integrally formed from a single tube bent to the desired configuration. The handlebar is indicated generally at 54 and has a forward extension 56 which may have the same configuration as the auxiliary handlebar 20 in the FIG. 1-7 embodiment. The handlebar has a pair of generally horizontal diverging rear sections 58 which will provide one hand gripping position for the rider. The sections 58 terminate in forwardly-extending sections 60 similar to the sections 18 of the FIG. 1-7 embodiment.
Arm rests 62 each include arm rest pads 64 that may be mounted at the top of an upward stem 66, the stems being fastened at the outward end, as shown in FIG. 9, of a generally horizontal support arm 68. The support arm is a part of an outer bracket 70 which, together with inner brackets 72 used for both arm rests, serves to mount both arm rests and to mount the handlebar to the bicycle stem. The length of stem 66 may vary so as to vary the height at which the arm rest pads are positioned above the handlebar sections 58 which will provide the hand gripping areas for the rider during a climbing mode.
The embodiment shown in FIG. 10 is similar to that described in FIGS. 8 and 9, except that those portions of the bar providing the climbing mode hand gripping position, indicated at 74, have a slight downward direction in contrast with the horizontal direction of the sections 58 in FIGS. 8 and 9. The other principal difference in the FIG. 10 embodiment is that the stems 76 which mount the arm rest pads are shorter than the stem 66 in FIGS. 9 and 11, thus illustrating variant positions for the arm rest pads.
The outer brackets for use in mounting the arm rests shown in FIGS. 8-11 are illustrated in FIGS. 12, 13 and 14. Outer bracket 70 with its horizontally extending support bar 68 has a plurality of holes indicated at 78 for use in varying the distance at which the arm rests are positioned from the point of attachment of the bracket. The bracket has an end section 79 with an interior gripping surface 80 so that the bracket will be firmly held to the handlebar. There is a bore 81 and an adjacent recess 82 for the two fasteners which are used to hold the outer bracket 70 to an inner bracket 72.
In the embodiment of FIGS. 15 and 16, the main handlebar is indicated generally at 83 and will be attached to a central stem 84. Handlebar 83 has central sections 86 on each side of the attachment to stem 84, adjacent down-turned sections 88 and forward extensions 90 which may provide one of the hand gripping positions on the handlebar.
The auxiliary handlebar is indicated generally at 92 and may have parallel forward sections 94 adjacent the up-turned and diverging sections 96, with the auxiliary handlebar terminating in the converging and upwardly-extending sections 98 which are joined together and which each provide the forward hand gripping positions for the rider when assuming an aerodynamic profile.
The arm rests are indicated at 100 and each may include an arm rest pad 102 on a small stem 104, with the stem being attached to a support bar 106 which again may have a plurality of mounting holes for variant mounting of the arm rests. The arm rests are each mounted to the handlebar by means of a lower bracket 108 and an upper bracket 110 held together by suitable fasteners 112. The upper mounting bracket 110 may have a bore indicated at 114 which receives the mounting ends of the auxiliary handlebar 92. The auxiliary handlebar may be attached by various means to the brackets, for example by fasteners, by a press fit, or by a suitable adhesive.
Of particular importance in the present invention is the means for locating and positioning the arm rests so as not to interfere with any potential hand positions on the principal handlebar. In one form of the invention the arm rests are spring biased to an up position away from the hand gripping portion of the handlebar. In another form of the invention, the arm rests are variantly positioned, both horizontally and vertically, to suit the rider's needs and to insure that the arm rests are away from the hand positions on the handlebar. The arm rest construction may be utilized with a handlebar in which the auxiliary portion is integral with the main handlebar or with a handlebar construction in which the auxiliary handlebar is separate.
Whereas the preferred form of the invention has been shown and described herein, it should be realized that there may be many modifications, substitutions and alterations thereto. | A bicycle handlebar construction provides a handlebar having first hand gripping portions and a forward extension having second hand gripping portions. There is a pair of arm rests mounted on the handlebars for support of a rider's arms when using the forward or second hand gripping portions. There are means for positioning the arm rests a distance away from the first hand gripping portions to prevent interference therewith when the rider is using the first hand gripping portions. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] None.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to tools, equipment, and fixtures used in the building and construction trades, and more specifically to a system for lifting and/or stabilizing foundations and the like.
[0004] 2. Related Art
[0005] As buildings age and settle there is sometimes a need for lifting or jacking the building foundation to make all parts of the building approximately level, which in turn repairs and prevents further damage to the building structure. There are numerous designs known in the art for systems for stabilizing and lifting building structures. These typically begin with a pier or piling driven or screwed into the ground beneath the building foundation, leaving a piling projecting upwards on which a lifting structure is attached. The lifting structure attaches to the piling and also to the building, with the lifting structure pushing against the piling to stabilize or raise the building.
[0006] Despite the variety of lifting systems currently available, these systems suffer from several drawbacks. The piers and pilings come in a variety of diameters, cross-sectional shapes, and lengths. At the lower end of the pier there is often attached a helical auger which helps to stabilize the pier, the augers vary in their diameter, pitch (i.e. angle of curvature), and number of turns. Thus it is necessary to keep in stock a large number of piers with helical augers attached in order to have at the ready a pier with the correct length shaft which also has the desired auger dimensions and shaft cross-sectional size and shape.
[0007] Furthermore, in some cases it is necessary to extend the length of a piling, for example when conditions are such that a pier is driven deeper into the ground than had been anticipated or provided for in advance. Thus there is a need for a way to extend the length of a piling while still maintaining adequate lifting strength.
[0008] Therefore, there is a need in the art to modularize pier and piling systems to reduce the number of parts that must be kept on hand while making assembly of pier systems easier.
[0009] There is also a need for keeping the lifting assembly closely attached to the building structure without slippage of the lifting assembly relative to the building structure.
[0010] Finally, there is a need for making the pilings sturdier and more rust-resistant.
[0011] The invention described below overcomes one or more of the above-described problems.
SUMMARY OF THE INVENTION
[0012] In one aspect the invention is a lift bracket system for lifting a building structure such as a foundation and the like comprising a lift plate having a top surface and a bottom surface, the top surface for insertion under the building structure; a generally cylindrical housing affixed to the lift plate and extending perpendicularly from the top surface and the bottom surface of the lift plate, the housing defining a generally circular opening through the lift plate, the opening being disposed away from the center of the lift plate; and at least one gusset for supporting the lift plate, the gusset having a first end and a second end, the gusset disposed beneath the lift plate, wherein the first end of the gusset is attached to the bottom surface of the lift plate and the second end of the gusset is attached to the housing.
[0013] In another aspect the invention is a support system for a building structure such as a foundation and the like comprising a pier disposed in the ground below the building structure to be supported, the pier comprising a support pile extending up toward the building structure; at least one extension piece, the extension piece having a first end and a second end, the first end having two pairs of holes therethrough and the second end having fixedly attached thereto a coupling, the coupling having two pairs of holes therethrough and being sized to receive a second pipe with generally mating holes, wherein the coupling is operably connected to the support pile; and a lift bracket operably connected to the extension piece.
[0014] In yet another aspect the invention is a method of lifting a building structure such as a foundation and the like comprising the steps of providing a pile anchored in the ground; affixing a lift bracket and a cap to the pile using a plurality of support bolts, the support bolts being attached to the cap with a plurality of nuts, wherein the lift bracket has a cylindrical housing; tightening each of the nuts to draw the lift bracket closer to the cap, thereby lifting the building; and attaching a bracket clamp to the lift bracket at a position determined by a preformed pair of holes in the lift bracket.
[0015] In still another aspect the invention is a modular foundation pier comprising a piling having a first cross-sectional size and a first cross-sectional shape; a sleeve having a second cross-sectional shape approximately the same as the first cross-sectional shape, the sleeve having a second cross-sectional size sufficiently larger than the first cross-sectional size so as to permit relative sliding of the sleeve along the piling; and a helical auger fixedly attached to the sleeve; wherein the sleeve is slid onto the piling and fixed thereto.
[0016] In another aspect the invention is an extension piece for a foundation pier comprising a shaft having a first end and a second end; a coupler attached to the first end of the shaft and having at least one pair of holes for receiving a fastener; and the second end of the shaft having at least one pair of holes for receiving a fastener.
[0017] Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
[0019] FIG. 1A shows a perspective view of one embodiment of the assembled lifting structure attached to a building structure.
[0020] FIG. 1B shows a complete assembly of a pier with modular piling collar, piling, extension piece, and lift bracket according to the present invention, with the bracket clamp positioned above the lift plate.
[0021] FIG. 2A shows a side view of an extension piece with its associated connector piece.
[0022] FIG. 2B shows a side view of a preferred embodiment of the extension piece attached to a pile by means of two perpendicularly situated fasteners.
[0023] FIG. 2C shows a side view of an embodiment of the extension piece with a connector attached at one end.
[0024] FIG. 2D shows a side view of an embodiment of the present invention in which a modular piling collar with a helical auger attached thereto is attached to a piling shaft.
[0025] FIG. 2E shows a perspective view of a modular piling collar for pilings having a circular cross section.
[0026] FIG. 2F shows a perspective view of a modular piling collar for pilings having a square cross section.
[0027] FIG. 2G shows a perspective view of a piling with a circular shaft attached to a piling with a square shaft using fasteners inserted into pairs of mating holes.
[0028] FIG. 3 shows a perspective view of a bracket body.
[0029] FIG. 4 shows a perspective view of a bracket clamp.
[0030] FIG. 5A shows a perspective view of a slider block with its associated bolt support pieces.
[0031] FIG. 5B shows a side view of a slider block.
[0032] FIG. 5C shows a top view of a slider block.
[0033] FIG. 6A shows a perspective view of a jacking block with its associated bolt support pieces.
[0034] FIG. 6B shows a side view of a jacking block.
[0035] FIG. 6C shows a top view of a jacking block.
[0036] FIG. 7 shows a perspective view of another embodiment of the assembled lifting structure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
[0038] After determining how the building or other structure needs to be lifted or supported, piles or pipes (hereinafter collectively referred to as a “pile” or “piles”) P attached to foundation piers or the like are set into the ground near the structure using known methods. The piers typically consist of a long shaft driven into the ground, upon which a lifting assembly is assembled. The shaft of the pier may include one or more lateral projections such as a helical auger to provide further support for the pier by providing a larger surface area. In some cases one or more extension pieces may be attached to the pier to extend it to the height of the building or to adapt a pile with a non-circular cross-section to a circular cross-section, as discussed below. The lifting assembly ( FIGS. 1A , 1 B) is then attached to the top end of pile P. If pile P is not long enough to allow the lifting assembly to interact properly with a foundation or other building structure B, one or more extension pieces ( FIG. 2A ; described below) can be added to pile P to adjust it to the correct length. Alternatively, if pile P is too long to permit proper assembly of the lifting assembly as described herein, then part of pile P can be removed using methods including, but not limited to, conventional cutting techniques. As another alternative, if extension pieces have been employed, as described below, then switching to a different length extension piece can be used as a method to adjust pile P to an advantageous elevation.
[0039] Support piles can come in various cross-sections including square or circular, and each cross-section can come in different diameters. Where the piling has attached to it a helical auger at its lower end ( FIG. 2D ), a large number of different pilings typically need to be kept in stock in order to have available every possible combination of cross-sectional shape and diameters with a variety of lengths as well as differing diameters of the helical auger portion. To eliminate this costly and burdensome practice, one embodiment of the present invention provides for a modular piling collar 700 , which consists of a sleeve 710 and a helical auger portion 720 that can be slid onto a piling shaft 730 and secured into place, for example with bolts. Helical auger portion 720 is firmly attached to sleeve 710 , preferably by welding. Modular piling collar 700 is made with sleeves of various cross sections and diameters and having helical augers with various diameters, pitches, and numbers of turns of the auger ( FIGS. 2E , 2 F). In one embodiment sleeve 710 has one or more pairs of holes 740 for attaching modular piling collar 700 onto piling shaft 730 , preferably with bolts. In a preferred embodiment there are two pairs of holes 740 which are aligned to accept orthogonally-disposed fasteners. To make a pier with a particular length one merely slides the appropriate modular piling collar onto a piling shaft of the desired length and affixes the modular piling collar in place. A preferred method for affixing the modular piling collar onto the piling shaft is by drilling mating holes in the piling shaft to match those on the sleeve and using fasteners such as bolts to hold the sleeve onto the piling shaft. In one embodiment the end of piling shaft 730 has a beveled tip 750 to better penetrate the ground during installation of the pier ( FIG. 2D ).
[0040] In the case where a pier with a non-circular piling shaft is employed, this can nonetheless be adapted for use with the lift bracket of the present invention, the lift bracket being described in further detail below. To adapt from a non-circular (e.g. square) to a circular piling shaft, a circular piling PI with an inside diameter at least as large as the largest cross-sectional dimension of the non-circular shaft is slid over the non-circular shaft 730 A ( FIG. 2G ). One or more sets of mating holes are drilled through the circular and non-circular shafts in the region where the shafts overlap and fasteners such as bolts B 10 are inserted through the holes to secure the shafts together. The lift bracket can then be slid onto the circular shaft as described further below.
[0041] The support pile extension piece 10 ( FIG. 2A ) comprises a variable-length shaft or body portion 20 comprising a length of pipe or other similar material, which in one embodiment is made from a metal such as iron. The extension piece body portion 20 in a preferred embodiment is of the same dimensions as the support pile to which it is attached, which in one embodiment is an outside diameter of 3.5 inches. The cross-sectional shape of extension piece 10 can be circular, square, hexagonal, or any other shape, although in preferred embodiments it is circular or square. The extension piece body portion 20 can be made to different lengths as the application requires. The first end of the extension piece body portion 20 has one or more pairs of holes 30 in it to allow for joining of adjacent pieces. If there is more than one pair of holes, as is the case in the preferred embodiment, the pairs of holes 30 are offset from one another along the long axis of the extension piece body portion 20 . In one embodiment the pairs of holes 30 are two inches apart and the first pair is two inches from the first end. The two members of each pair are on opposite sides of the pile, such that a fastener extending through holes 30 will be generally perpendicular to the long axis of the extension piece and will enter and leave the extension piece body portion 20 approximately normal to the surface. In a preferred embodiment the first end has two pairs of holes 30 , which are preferably rotationally offset from one another by 90° such that fasteners 45 inserted into the holes are perpendicular to one another when extension piece 10 is viewed in cross-section ( FIG. 2B ).
[0042] The second end of extension piece 10 comprises a coupler or connector piece 40 attached to the second end of the body portion 20 ( FIG. 2A ). Connector piece 40 is preferably externally disposed (although internally-disposed connectors are also encompassed within the invention) with an inside diameter that is large enough to accommodate the outside diameter of the adjacent pile or extension piece to which it is attached. Connector piece 40 in this embodiment is preferably made from a piece of pipe having a larger diameter than the main body of the extension piece and is attached to the extension piece body portion 20 in a fixed manner, such as by welding. Connector piece 40 has one or more holes 30 that mate with those on the adjacent pile or extension piece, such as those described above for the first end of the extension piece. In a preferred embodiment there are two pairs of holes, offset from one another along the long axis of the connector piece and offset by 90° rotationally, as described above ( FIG. 2B ). In one embodiment connector piece 40 is eight inches long and the pairs of holes 30 are two inches apart and one such pair is two inches from the end of connector piece 40 that is distal to body portion 20 itself. Extension piece 10 is joined to an adjacent extension piece or to a pile P by inserting fasteners, such as bolts, through the substantially mating pairs of holes of the adjoining components, as are described above ( FIG. 2B ). Holes 30 at both ends of extension piece 10 are, in a preferred embodiment, 15/16ths inches in diameter. Holes of a similar size and location so as to mate with those on extension piece 10 must be made in pile P, either in advance or at the job site.
[0043] In one embodiment the extension piece(s) and/or pile are filled with what is preferably a non-metallic substance such as light concrete or chemical grout 50 ( FIG. 2C ). The addition of filler to the extension pieces helps to strengthen the pieces and, by excluding water from the insides, makes them more rust-resistant. The piles and/or extension pieces can be filled ahead of time (leaving space open for the pieces to couple and for the fasteners to enter) or can be filled after assembly at the job site by inserting filler material into the piles or extension pieces, including into access hole 60 ( FIG. 2C ). If the extension pieces have been prefilled except near the pairs of holes where the fasteners go through, then the remaining space can be filled after assembly by inserting additional filler material into access hole 60 ( FIG. 2C ). Access hole 60 is situated on the side of connector piece 40 with a substantially mating access hole 60 being present at the end of extension piece 10 .
[0044] When support pile P, or a pile plus extension piece(s), has been assembled and adjusted to the correct height relative to the building or other structure, the lifting assembly can be slid onto the pile or extension piece P (for simplicity, hereinafter “pile P” refers to either the pile itself or any extension piece or pieces added onto the pile and to which the lifting assembly is attached, unless stated otherwise).
[0045] The lifting assembly ( FIG. 1A ) in a preferred embodiment comprises a bracket body 100 , one or more bracket clamps 200 and accompanying fasteners, a slider block 300 , and one or more supporting bolts 400 (comprising allthread rods, for example) and accompanying hardware. In another embodiment ( FIGS. 1B , 7 ) the lifting assembly includes all of the above components as well as a jacking block 500 and a jack 600 .
[0046] The bracket body 100 comprises a generally flat lift plate 110 , one or more optional gussets 120 , and a generally cylindrical housing 130 ( FIG. 3 ). The lift plate has a top surface and a bottom surface, where the top surface is inserted under and interacts with the building, foundation or other structure that is to be lifted or supported. Lift plate 110 includes a large hole 140 , preferably off-center, with which cylindrical housing 130 is aligned and to accommodate pile P. The corners 150 of lift plate 110 that are further from large hole 140 are preferably rounded or chamfered, to make it easier to rotate the bracket body into position under the building structure. Cylindrical housing 130 runs generally perpendicular to the surface of lift plate 110 and extends above and below the plane of lift plate 110 . In one embodiment cylindrical housing 130 extends eight inches above and eight inches below the plane of lift plate 110 . Cylindrical housing 130 can be made of either a single cylindrical piece of pipe or other material that extends through the lift plate, or alternatively can be made of two separate pieces that are attached to the top and bottom surfaces of lift plate 110 , respectively, and are aligned with large hole 140 .
[0047] In a preferred embodiment one or more gussets 120 are attached to the bottom surface of lift plate 110 as well as to the lower portion of cylindrical housing 130 , to increase the holding strength of lift plate 110 . In a preferred embodiment, gussets 120 are attached to cylindrical housing 130 by welding, although other secure means of attachment are encompassed within this invention.
[0048] In addition to large hole 140 for accommodating pile P, lift plate 110 has one or more small holes 160 sized to accommodate support bolts 400 . Cylindrical housing 130 has one or more pairs of holes 170 to accommodate fasteners (not shown), as described below. The pairs of holes 170 in cylindrical housing 130 are on opposite sides of the housing and are oriented normal to the surface of the housing, such that a fastener extending through the holes is perpendicular to the long axis of cylindrical housing 130 and extends towards building structure B when lift plate 110 is inserted under building structure B.
[0049] Bracket clamps 200 ( FIG. 4 ), in one embodiment, comprise a generally L)-shaped piece having a center hole 210 at the apex of the “Li” to accommodate a fastener (not shown). The ends of the a-shaped bracket clamp have ears or lugs 220 preferably extending laterally, which themselves have holes 230 to accommodate fasteners (not shown). The fasteners extending through holes 230 in lugs 220 are attached to the building structure, while the fastener extending through center hole 210 at the apex of the “a” extends into one of holes 170 in cylindrical housing 130 . In one embodiment the fastener extending through center hole 210 in bracket clamp 200 and into cylindrical housing 130 further extends through pile P and into hole 170 on the opposite side of cylindrical housing 130 , and in one embodiment this fastener then anchors into the building structure. In embodiments where the fastener extends into pile P (with or without a bracket clamp), a hole or holes are made in pile P to accommodate the fastener, using known methods. In such cases, however, the fastener is not inserted through pile P until jacking or lifting has been completed, since bracket body 100 must be able to move relative to pile P in order to effect lifting of the building structure.
[0050] The lift assembly may have one or more of the above-described bracket clamps 200 . Bracket clamps 200 are attached above ( FIG. 1 B) and/or below ( FIGS. 1A , 7 ) lift plate 110 , depending on the structure to be lifted. Bracket clamps 200 are attached to cylindrical housing 130 at predetermined, nonadjustable points, where pairs of holes 170 have previously been made in cylindrical housing 130 .
[0051] Bracket body 100 is placed onto pile P with the larger portion of lift plate 110 facing away from the building structure. When bracket body 100 is at the desired elevation relative to the building structure, bracket body 100 is rotated until lift plate 110 is securely under the building structure. At this point one or more bracket clamps 200 , as described above, can be attached to bracket body 100 at the predetermined locations which are dictated by the locations of pairs of holes 170 in cylindrical housing 130 . Also at this time bracket clamps 200 are secured into building structure B, since it is desired that during the lifting process bracket body 100 should remain fixed relative to the building structure ( FIGS. 1A , 1 B).
[0052] After adjusting the position of bracket body 100 , slider block (or “t-cap”, or “cap”) 300 is placed on top of bracket body 100 ( FIGS. 1A , 1 B). Slider block 300 comprises one or more flat base plates 310 , one or more side plates 320 , one or more center plates 330 , a support pipe 340 , and one or more bolt support pieces 350 . In a preferred embodiment slider block 300 comprises one base plate 310 , two side plates 320 , one center plate 330 , one support pipe 340 , and two support pieces 350 ( FIGS. 5A-5C ). Support pieces 350 are preferably square or rectangular and are large enough to overlap with both side plates 320 , when side plates 320 are configured as described below, and having a hole 360 sized to accommodate a support bolt 400 . Base plate 310 is preferably flat and rectangular and has one or more (preferably two) holes 370 for accommodating the support bolts ( FIG. 5C ). Support pipe 340 is attached approximately in the center of the bottom surface of base plate 310 . Side plates 320 , which are preferably flat and rectangular, are oriented on their narrower edges with their long axes parallel to the long axis of base plate 310 . Center plate 330 , which is preferably the shape of a squat rectangular block, is disposed between side plates 320 and is in substantial contact with side plates 320 and base plate 310 , such that center plate 330 holds side plates 320 stably on their narrower edges. The long axis of center plate 330 is shorter than that of base plate 310 , so that center plate 330 does not obstruct any of holes 370 in base plate 310 . Holes 370 in base plate 310 are spaced to match the center-to-center distance(s) of holes 160 in bracket body 100 . All of the components of slider block 300 are preferably metal and, except for support pieces 350 , are rigidly attached to one another, for example by welding. Support pipe 340 extending from the bottom surface of base plate 310 of slider block 300 is sized to mate with the inside of cylindrical housing 130 of bracket body 100 and has generally the same outside diameter as that of pile P.
[0053] The length of pile P must be adjusted, as previously mentioned, so that the top end of pile P terminates within cylindrical housing 130 . When slider block 300 is placed on top of bracket body 100 , the end of support pipe 340 of slider block 300 should touch the top end of pile P. It is preferred that the respective ends of support pipe 340 and pile P meet squarely and with as much surface contact as possible, since it is the pushing of support pipe 340 against pile P that leads to lifting of the building structure. It is preferred that the distance between the bottom surface of base plate 310 of slider block 300 and the top of cylindrical housing 130 of bracket body 100 be greater than or equal to the total anticipated lifting distance required. When the bottom of base plate 310 of slider block 300 makes contact with the top of cylindrical housing 130 of bracket body 100 then no more lifting can occur since slider block 300 can no longer move relative to bracket body 100 .
[0054] After slider block 300 and bracket body 100 are in place, support bolts 400 are assembled ( FIGS. 1A , 1 B). At their top ends the support bolts extend through the holes in the slider block and are held in place by a mating nut 410 and an optional washer 420 . Nut 410 and washer 420 are held in place on top of slider block 300 by inserting therebetween on each bolt 400 a support piece 350 . Support piece 350 rests on the top edges of side plates 320 of slider block 300 . Support pieces 350 serve to keep nuts 410 above and out of the channel between side pieces 320 so that nuts 410 are accessible and can be turned more readily. The lower ends of support bolts 400 extend through small holes 160 in lift plate 110 of bracket body 100 and are held in place by mating nuts 410 and optional washers 420 attached on the ends of bolts 400 extending through the bottom surface of lift plate 110 .
[0055] Although the preferred embodiment described herein uses two supporting bolts 400 , the invention encompasses any number of such bolts.
[0056] In one embodiment bracket body 100 is raised by tightening nuts 410 attached to the top ends of supporting bolts 400 . In a preferred embodiment nuts 410 are tightened simultaneously, or alternately in succession in small increments with each step, so that the tension on bolts 400 is kept roughly equal throughout the lifting process. Use of this method allows the weight supported by bracket body 100 to be transferred equally between each of bolts 400 to prevent over-stressing one of bolts 400 . Also, maintaining equal tension assures that, in the preferred embodiment with two bolts 400 , bracket body 100 remains substantially level and does not cant or tilt during the lifting process. Such canting or tilting could cause support pipe 340 or pile P inside cylindrical housing 130 to bind, thereby inhibiting the sliding motion relative to cylindrical housing 130 that is required during the lifting process.
[0057] An alternative embodiment allows a jack to be used to effect lifting of bracket body 100 . In this embodiment longer support bolts 400 are provided and are configured to extend high enough above slider block 300 to accommodate: a jack 600 resting on slider block 300 , a jacking block 500 , plus the combined thickness of a support piece 350 along with a nut 410 and an optional washer 420 ( FIG. 7 ).
[0058] Jacking block 500 is similar to slider block 300 except that jacking block 500 does not have a support pipe extending from its underside ( FIGS. 6A-6C ). Jacking block 500 has one or more holes 510 similar in size and location to those of slider block 300 and bracket body 100 to accommodate support bolts 400 ( FIG. 6C ). To accommodate jacking block 500 an assembly is constructed as described above with bracket body 100 positioned on pile P, lift plate 110 inserted under the building structure, slider block 300 inserted on top of bracket body 100 , and support bolts 400 attached with a portion extending above slider block 300 . A jack 600 is then placed atop slider block 300 and jacking block 500 is thereafter positioned on top of jack 600 , with support bolts 400 extending through holes 510 of jacking block 500 . Support pieces 520 , nuts 410 , and optional washers 420 are then put onto the ends of bolts 400 and tightened with approximately equal tension placed on each nut 420 . As with the previous lifting embodiment, the distance between the bottom of slider block 300 and the top of cylindrical housing 130 must be at least the same as the distance that it is anticipated the building structure needs to be lifted.
[0059] When all of the components are in place and sufficiently tightened, jack 600 (of any type, although a hydraulic jack is preferred) is activated so as to lift jacking plate 500 . As jacking plate 500 is lifted, force is transferred from jacking plate 500 to support bolts 400 and in turn to lift plate 110 of bracket body 100 . When the building structure has been lifted to the desired elevation, nuts 410 immediately above slider block 300 (which are raised along with support bolts 400 during jacking) are tightened down, with approximately equal tension placed on each nut 410 . At this point jack 600 can then be lowered while bracket body 100 will be held at the correct elevation by the tightened nuts 410 on slider block 300 . Jacking block 500 can then be removed and reused. The extra support bolt material above nuts 410 at slider block 300 can be removed as well, using conventional cutting techniques.
[0060] To help solidify the structure one or more bracket clamps 200 can be attached, if this has not already been done, or additional bracket clamps 200 may added. Bracket clamps 200 are aligned with the pairs of holes 170 on the cylindrical housing 130 and are anchored into building structure B using fasteners inserted through the ears or lugs 220 . An additional fastener is then inserted into center hole 210 in the apex of the )-shaped portion of bracket clamp 200 . This fastener is optionally driven through pile P or support pipe 340 (depending on where the pairs of holes are situated and depending on how far into the cylindrical housing support pipe 340 runs) and into the opposite side of cylindrical housing 130 and optionally into the building structure. If necessary a hole is made in the portion of pile P or support pipe 340 that is inside cylindrical housing 130 to accommodate the fastener.
[0061] As various modifications could be made to the exemplary embodiments, as described above with reference to the corresponding illustrations, without departing from the scope of the invention, it is intended that all matter contained in the foregoing description and shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents. | A lift bracket system for lifting a building structure such as a foundation and the like comprising a lift plate having a top surface and a bottom surface, the top surface for insertion under the building structure; a generally cylindrical housing affixed to the lift plate and extending perpendicularly from the top surface and the bottom surface of the lift plate, the housing defining a generally circular opening through the lift plate, the opening being disposed away from the center of the lift plate; and at least one gusset for supporting the lift plate, the gusset having a first end and a second end, the gusset disposed beneath the lift plate, wherein the first end of the gusset is attached to the bottom surface of the lift plate and the second end of the gusset is attached to the housing. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority to U.S. Provisional Patent Application Ser. No. 60/968,799, filed Aug. 29, 2007, the entire contents of which are specifically incorporated herein by reference.
BACKGROUND
[0002] Geophysical exploration is an important part of the hydrocarbon recovery industry. Seismic and/or acoustic measurements and monitoring have long been viewed as a particularly effective means for measuring and monitoring the geophysical and reservoir environment downhole.
[0003] Commonly, seismic and/or acoustic information is gained from the wellbore either through a wireline tool in real time or in LWD more recently through processing and storage of received information at the downhole tool. In LWD a small subset of this information may be pulsed uphole, for example, with some delay in time due to limited bandwidth. The total recorded information is later brought to the surface for downloading and analysis. While wireline provides for a number of different functions in real time within the wellbore, the wireline itself occludes the flow passage within a string in which it is placed. Further, wireline measurements are acquired only after a well has been drilled to certain depth and therefore wireline is not effective to address the “while drilling” needs. Because of the occlusion, other wellbore operations are significantly hindered during a wireline testing process. Nevertheless wireline testing has been the gold standard for a substantial period of time where a borehole seismic and/or acoustic measurement is desired.
[0004] Where wireline is not the tool of choice, vibrations may be sent through the mud column or the drill string itself although compensation related to signal path velocity is required to determine the time value of the measurement. The method further suffers from having a limited bandwidth available. In such systems typically a seismic source would be located at the surface and transmit seismic energy in the downhole strata, which is recorded by sensors located downhole. The source does not need to be on the surface, however, as it maybe located downhole. Further, the source may be an acoustic source or noise created by a drill bit. This energy would then be measured at the sensor(s) either by a direct signal path or be reflected back to the sensors for the downhole measurement and stored there. In either event information is not rapidly obtained.
SUMMARY
[0005] A seismic and/or acoustic while drilling configuration includes a high speed telemetry arrangement; at least one seismic and/or acoustic energy sensor in communication with the high speed telemetry arrangement; at least one seismic and/or acoustic energy source capable of producing at least one seismic and/or acoustic energy signal receivable by the at least one seismic and/or acoustic energy sensor.
[0006] A method for monitoring a wellbore while drilling includes measuring seismic and/or acoustic energy at a downhole location; transmitting a signal representative of the seismic and/or acoustic energy through a high-speed telemetry arrangement to a remote location.
[0007] A method for monitoring a formation while drilling includes stopping movement of the drill string; listening for sounds of the formation without running an additional tool; recommencing movement of the drill string.
[0008] A method for 4D monitoring a formation after drilling includes introducing into a seismic and/or acoustic while drilling configuration including a high speed telemetry arrangement; at least one seismic and/or acoustic energy sensor in communication with the high speed telemetry arrangement; at least one seismic and/or acoustic energy source capable of producing at least one seismic and/or acoustic energy signal receivable by the at least one seismic and/or acoustic energy sensor; initiating a seismic and/or acoustic signal from the seismic and/or acoustic source; and monitoring the signal over time.
[0009] A method for at least one of monitoring, adapting and operating in the wellbore while drilling includes introducing into a seismic and/or acoustic while drilling configuration including a high speed telemetry arrangement; at least one seismic and/or acoustic energy sensor in communication with the high speed telemetry arrangement; at least one seismic and/or acoustic energy source capable of producing at least one seismic and/or acoustic energy signal receivable by the at least one seismic and/or acoustic energy sensor; sending a signal over the high-speed telemetry arrangement to a sensor in the downhole environment; causing the sensor to deploy into contact with a target formation; measuring a parameter of the formation with the sensor; telemetering information measured by the sensor to a remote location.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Referring now to the drawings wherein like elements are numbered alike in the several Figures:
[0011] FIG. 1 is a schematic illustration of a drill string having a high-speed telemetry arrangement, a drill bit, seismic and/or acoustic source, and seismic and/or acoustic sensor.
DETAILED DESCRIPTION
[0012] Referring to FIG. 1 , a three-quarter sectional schematic view of a wired pipe 10 (a high-speed telemetry arrangement) and a drill bit 12 is presented for clarity of disclosure. A conductor 14 is illustrated and embedded within a thickness of a wall 16 of the wired pipe 10 . A flow area 18 is illustrated as patent, there being no restriction due to, for example, a wireline or other more fixed configuration extending therein for the purpose of communication or sensing. In the configuration illustrated in FIG. 1 , the conductor 14 enables high-speed telemetry such that real-time seismic and/or acoustic while drilling is both possible and enhanced in function. The high-speed telemetry capability allows the transmission of raw data or waveform, partially processed results or the initial final results or combinations of these over time as desired. This allows the operator to adjust various parameters including such things as the slowness results or tool operating parameters including but not limited to acquisition modes (e.g. changing of the quadrupole to high frequency for fast formations or the changing to a CBL (casing bond log) mode while in casing) and also allows control of the acquisition of for example acoustic data (depth based as opposed to time based). Configurations contemplated, then, include a seismic and/or acoustic source(s) at surface with seismic and/or acoustic receiver(s) downhole; seismic and/or acoustic receiver(s) at the surface and a seismic and/or acoustic source(s) downhole; and receiver(s) and source(s) downhole (where the source(s) is active or passive). Because of the high-speed telemetry capability, each of the configurations noted are possible where they were not possible prior to the configuration illustrated schematically in FIG. 1 . Further, because of the high-speed telemetry capability, the traditional exceptionally accurate clock (not shown) that has been required in the downhole environment in order to obtain useful seismic and/or acoustic information is no longer required. The configuration of FIG. 1 allows for a less accurate clock to be used or even for the clock to be eliminated, which of course reduces costs in association with the gathering of seismic and/or acoustic information. Where a lower accuracy clock is retained, data received from the system can be improved by sending a synchronization signal from a remote location, such as the surface, where the seismic and/or acoustic source is located, to the downhole clock thereby synchronizing a surface clock and the downhole lower accuracy clock.
[0013] In addition to the foregoing, utilization of the configuration illustrated in FIG. 1 allows for the implementation of a seismic and/or acoustic source 20 in close proximity to the drill bit 12 . Such a source may be active or passive but in either case because the source is proximate the drill bit 12 , pipe string velocity no longer needs to be taken into account when rectifying information obtained through sensory monitoring. Further, a passive seismic and/or acoustic source can be the drill bit itself (creating a pilot or true reference signal) with a sensor positioned as schematically illustrated at 22 . Because there is no significant distance between the drill bit and sensor there is no reason to calculate velocity of vibration along the drill string but rather any loss would be negligible. The wired pipe then provides high-speed telemetry of information to the surface or other remote location created for the purpose of receiving that information. Since utilizing the drill bit as a seismic and/or acoustic source is indeed popular though burdened by the inherent inaccuracy associated with attenuation of the signal at a remote location, the configuration and method disclosed herein to telemeter at high speed information gained by sensor 22 adjacent the drill bit 12 without concern for attenuation of the signal over the length of the drill pipe will be very well received by the art.
[0014] Another method disclosed herein is of stopping the drill string momentarily and listening to the formation over a period of time. Immediately following the listening, the drill string may be reactivated and drilling continued. Such a method provides a significant advantage of periodically listening to the wellbore sounds without having to run a wireline or remove any other well equipment. This reduces costs associated with the reduction of drilling activity that is inherent in the prior art. In other words, drilling is maximized while downtimes minimized.
[0015] In another aspect, the configuration and method taught herein enables the monitoring of geophysical and or reservoir properties such as gas caps, water floods, water legs, and other general changes in the reservoir. Mapping of these conditions over time provides valuable information about the health of the formation and about its potential future production capability. The ability to monitor these conditions over time is enabled by the configuration illustrated in FIG. 1 . Since the seismic and/or acoustic sensor 22 is placed directly on the drill pipe or production string and adjacent the drill bit 12 the operator can listen at anytime desired and transmit all information up the conductor 14 to a surface or other remote location in real time. This can be continued for as long as it is desired thereby providing, at for example a surface location, a real time picture in three dimensions of a geophysical property and the changes in that property over time. This is tremendously advantageous to the borehole operator enabling significantly more efficiency with respect to ultimate wellbore production.
[0016] In yet another aspect, the conductor 14 and its high-speed telemetry capability also facilitates improved use of geophones. As one of ordinary skill in the art will clearly understand, geophones function best when in solid contact with the formation. Because drill bits are rotated, geophones depending therefrom in a radially outward direction tend to be damaged relatively easily. Geophones, therefore, are sometimes eschewed in favor of hydrophones, which do not require contact with the formation. Hydrophones are effective for their intended purpose of measuring pressure. It will be recognized, however, that geophones in some applications are more useful because, for example, in a particular situation, displacement of the formation is more relevant than the pressure of the formation. Conductor 14 is again beneficial to the operator in connection with the configuration of FIG. 1 since geophones may be deployable at will from the surface location. In other words, a signal may be sent down conductor 14 that causes the geophones to be extended from the drill pipe into contact with the formation. This would, of course, be done while the drill bit remains stationary. In one embodiment, the geophones would be extended utilizing solenoids that are responsive to signals carried on conductor 14 . Once the geophones are placed into solid contact with the formation, they can be used to measure formation displacement to the extent desired by the operator. When measuring is concluded, the geophones maybe retracted pursuant to another signal carried on conductor 14 , or perhaps a lack of signal on conductor 14 , placing them in a protected position while drilling recommences.
[0017] The astute reader may notice from the foregoing paragraph that another capability is enabled by the configuration of FIG. 1 . That is that because of conductor 14 , communication with downhole tools is possible. This communication can be used to activate or deactivate different tools, test certain components of the downhole tools monitor sensors designed to measure formation contact with other sensors, etc. This provides for the first time with respect to seismic and/or acoustic while drilling the real-time ability to watch and modify both the tool and the downhole environment.
[0018] In another aspect, it is noted that because of the conductor 14 , multiple sensors may be used in the downhole environment since signals may be piggybacked on one another on the conductor 14 , and due to the speed with which conductor 14 can convey information, more sensors can over time be addressed and transmit information to the surface location. Moreover, because sensors may be distributed along the drill pipe 10 , processes such as Q measurement may be affected more efficiently since the high frequency attenuation inherent in this measurement method can be measured more accurately over specific smaller distances over the length of the drill pipe.
[0019] While the invention has been described with reference to exemplary embodiments, it will be understood that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications will be appreciated by those skilled in the art to adapt a particular instrument, situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. | A seismic and/or acoustic while drilling configuration includes a high speed telemetry arrangement; at least one seismic and/or acoustic energy sensor in communication with the high speed telemetry arrangement; at least one seismic and/or acoustic energy source capable of producing at least one seismic and/or acoustic energy signal receivable by the at least one seismic and/or acoustic energy sensor and methods. | 4 |
FIELD OF THE INVENTION
This invention relates generally to the field of turbochargers and, more particularly, to a system for controlling electric assisted turbochargers.
BACKGROUND OF THE INVENTION
Turbochargers for gasoline and diesel internal combustion engines are devices known in the art that are used for pressurizing or boosting an intake air stream, routed to a combustion chamber of the engine, by using the heat and volumetric flow of exhaust gas exiting the engine. Specifically, the exhaust gas exiting the engine is routed into a turbine housing of a turbocharger in a manner that causes an exhaust gas-driven turbine to spin within the housing. The exhaust gas-driven turbine is mounted onto one end of a shaft that is common to a radial air compressor mounted onto an opposite end of that shaft. Thus, rotary action of the turbine also causes the air compressor to spin within a compressor housing of the turbocharger that is separate from the exhaust housing. The spinning action of the air compressor causes intake air to enter the compressor housing and be pressurized or boosted a desired amount before it is mixed with fuel and combusted within the engine combustion chamber.
Because the rotary action of the turbine is dependent upon the heat and volumetric flow of exhaust gas exiting the engine, turbochargers are often of reduced effectiveness when the engine to which they are coupled is run at a low speed. The reduced effectiveness is often labeled turbo-lag. In order to overcome turbo-lag when the heat and volumetric flow of exhaust gas is low, an electric motor is known for rotating the shaft and inducing the compressor to spin.
Without proper timing and power provision to the electric motor, the electric motor can hinder rather than enhance the performance of the turbocharger. It is, therefore, desirable to provide intelligent operation control to the electric motor in order to both maximize engine performance, and to provide a responsible electric power management system. It is desired that such intelligent operation control system be configured to prevent powering the electric motor of the electric assisted turbocharger during engine operating conditions not calling for turbocharger assistance.
Additionally, engine designers constantly seek improvements for controlling boost pressure on an engine. In an effort to more rapidly and more precisely control boost pressure, in a conventional turbocharger, designers have replaced pneumatic actuators with electronic controlled actuators for moving wastegate valves and variable geometry blades. The electronic actuators receive their instructions from the engine electronic control unit (ECU) and various engine sensors. This results in a reduction in time to reach a target boost pressure, and smaller over-boost and under-boost error margins.
It is, therefore, also desirable that an intelligent operation control system for use with an electric assisted turbocharger be configured to reduce the time needed to reach a target boost pressure, and to reduce over-boost and under-boost error margins, thereby enabling an improved degree of turbocharger efficiency.
SUMMARY OF THE INVENTION
A system for controlling an electric assisted turbocharger, constructed according to principles of this invention, employ an electric motor that is disposed within a turbocharger, an electric motor controller is electrically coupled to the electric motor for purposes of controlling the same, and a memory means is electrically coupled to the electric motor controller. The memory means is configured having a condition map that correlates electric motor instructions with engine and turbocharger conditions. The system includes a number of sensors that are electrically coupled to the electric motor controller. The sensors are configured to sense conditions of at least one of the turbocharger and the internal combustion engine that is coupled thereto.
The electric motor controller is configured to control the electric motor based upon the input received from the plurality of sensors as compared to the data contained in the multi-dimensional condition map. In an example invention embodiment, the motor controller is configured to operate the electric motor of the electric assisted turbocharger in a manner best suited to provide the desired engine performance. For example, the system may comprise a clutch engagement sensor, that senses whether a clutch is engaged, and or a brake engagement sensor, that senses whether a brake is engaged, and the electric motor controller is configured to remove power to the electric motor when the clutch engagement sensor and/or the brake sensor indicates that the clutch is not engaged or the brake is activated.
In another invention embodiment, the system comprises a boost pressure sensor that senses the boost pressure in the turbocharger and that is configured to achieve a target boost pressure, and to reduce over-boost and under-boost error margins. In such embodiment, the electric motor controller is configured to select a target boost pressure based upon application of the sensed conditions of at least one of the turbocharger and the internal combustion engine to the condition map in the memory. The system is configured to supply increased power to the electric motor when the boost pressure sensed by the boost pressure sensor is lower than the selected target boost pressure, and to supply decreased power to the electric motor when the boost pressure sensed by the boost pressure sensor is higher than the selected target boost pressure. Additionally, the system can be configured to operate in a generator mode, whereby the electrical motor is operated to produce electricity based on the spinning of the turbine by the exhaust gas.
BRIEF DESCRIPTION OF THE DRAWINGS
The aspects of the present invention are more readily understood when considered in conjunction with the accompanying drawings and the following detailed description wherein:
FIG. 1 is a schematic diagram illustrating an electric assisted turbocharger control system, constructed according to principles of this invention;
FIG. 2 is a graph of boost pressure (y-axis) as a function of time (x-axis) illustrating the impact of using electric dampening, according to principles of this invention, to improve boost pressure control; and
FIG. 3 is a flow diagram illustrating of system for providing boost pressure control according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Control systems for electrically assisted turbochargers, constructed according to principles of this invention, comprise a control means that is electrically coupled to an electric motor of the turbocharger, and that is connected with a plurality of sensors configured to monitor a number of different engine and/or turbocharger operating parameters. A memory means is coupled to the control means and has stored in it a condition map comprising information relating to predetermined operating conditions of the engine and/or turbocharger. The system monitors the sensed operating conditions, and operates the electric motor in the turbocharger according to certain predetermined operating instructions provided by the condition map, in a manner best addressing the particular engine operating requirements.
As shown in FIG. 1, an electrically assisted turbocharger 10 generally comprises an electric motor 12 that is disposed around a turbocharger shaft 14 interconnects the turbine 16 and the compressor 18 . The Electric motor 12 is disposed within the turbocharger adjacent the center housing 20 , and is interposed axially between the center housing 20 and a compressor housing 22 that houses the compressor 18 . The turbine 16 is disposed within a turbine housing 24 .
An electric motor control system/controller 26 for controlling the electric assisted turbocharger is electrically coupled to the electric motor 12 . In an example embodiment, the control system comprises an engine Electronic Control Unit (ECU) 28 and an independent power controller 30 . The engine ECU is electrically coupled to the independent power controller 30 . The system also comprises multiple sensors 32 that are electrically coupled to at least one of the engine ECU 28 and the independent power controller 30 . The independent power controller 30 is electrically coupled to the electric motor 12 of the turbocharger 10 . The electric motor 12 is disposed around the turbocharger shaft 14 and is configured to apply a torque to the shaft, and attached compressor 18 , in either direction of rotation.
A memory and a microprocessor is connected with, or can be part of, at least one of the engine ECU 28 and the power controller 30 . The memory is electrically coupled to the microprocessor, and is programmed having a plurality of condition maps for different turbocharger control schemes. The condition maps are configured to correlate a desired action of the electric motor 12 with determinable engine and turbocharger characteristics. The microprocessor uses engine signals and sensor inputs in conjunction with the condition map data stored in the memory to control the electric motor 12 of the electric assisted turbocharger 10 . The independent power controller 30 is used to control the flow of power to the electric motor 12 . In an embodiment of the present invention, the independent power controller functions to convert power to the electric motor from direct current (DC), e.g., supplied by an on-board vehicle battery, to alternating current (AC) used to power the electric motor. In some operating instances, the electric motor 12 of the electric assisted turbocharger 10 can be operated to act as a generator to draw power from the spinning of the turbine 16 caused by the exhaust gas pressure. When the electric motor 12 is operated to perform in the function of a generator, the independent power controller functions to convert the power provided from the electric motor from AC to DC. This generated DC power can be used to power desired electric features of the vehicle, or simply be used to maintain the charge of the on-board battery. The independent power controller is also configured to perform power conditioning and is capable of intelligent speed control.
The control system of this invention is configured to control operation of the electric motor according to the following control scheme. Depending on the current operating conditions of the engine and the performance demanded by the driver, the system is configured to operate in one of the three following modes: (1) a motor mode; (2) a generator mode; or (3) a neutral mode. In the motor mode, the electric motor is operated by the controller to spin the shaft 14 of the turbocharger to increase the boost of intake air to the engine. In a neutral mode, the turbocharger operates on the temperature and volume of exhaust gas of the engine without any assistance from the electric motor. In a generator mode, the electric motor is operated to produce electricity based on the spinning of the turbine 16 by the exhaust gas of the engine.
The magnitude of power that is supplied to, or generated from, the electric motor can vary depending on the particular engine and/or turbocharger operating condition, and is determined by the difference between current operating conditions (as monitored by one or more of the sensors) and driver demanded performance as programmed into the condition maps. Thus, if a driver is demanding that the engine provide maximum thrust, then the system will operate to activate the electric motor to enhance the boost provided by the compressor rather than as a generator to generate electricity. The system has the flexibility to accommodate different control algorithms for different applications. In an embodiment of the present invention, a control algorithm is designed for maximum boost from the turbocharger at the expense of some power generation by the electric motor. In an additional embodiment of the present invention, a control algorithm is designed for generating the maximum amount of electricity possible from the electric motor of the turbocharger at the expense of some boost. The function that the engine ECU and the power controller play in performing control tasks varies from one application to another.
The sensors 32 are configured to monitor at least one of the following exemplary engine and turbocharger conditions: intake air flow; engine revolutions per minute (RPMs); engine load; boost pressure and temperature; intake manifold pressure and temperature; accelerator position; accelerator change rate; fueling rate; engine temperature; engine timing; battery voltage; electric motor current flow; ambient temperature and pressure; brake pressure; clutch pressure; oil pressure; turbocharger speed; and a temperature of the electric motor winding in the turbocharger.
In an embodiment of the present invention, the system is configured to prevent an undesired powering of the electric motor in the turbocharger when not necessary. One situation in which the electric motor powering of the turbocharger is not necessary is when a driver “revs” the engine at a stop light. Although the driver is pressing down on the accelerator, the driver does not need the turbocharger to be activated. An additional situation where power of the electric motor in the turbocharger is not necessary is when the driver of a stick shift vehicle changes gears, i.e., when the clutch is being depressed.
In order to prevent activation of the electric motor of the turbocharger when a driver is revving an engine at a stop light, and when a driver is switching manual transmission gears, a first sensor is provided for sensing whether the clutch is engaged. A second sensor is provided for sensing whether the brakes are engaged.
In an embodiment where the control algorithm is configured for normal driving, current flow to the electric motor will be prevented when the first sensor senses that the clutch is not engaged, indicating that the driver is shifting gears. Likewise, current flow to the electric motor will be prevented when the second sensor senses that the brakes are engaged, indicating that the driver is revving the engine at a stop light. In alternative embodiments, the controller may be configured to operate differently depending on the particular control algorithm being utilized by the microprocessor.
In an additional embodiment of the present invention, the above described system is used to improve boost pressure control of an electric assisted turbocharger. In a conventional variable geometry turbocharger, when an engine's ECU determines that the turbocharger should spin up to a target boost pressure, the ECU signals the nozzle vanes of the variable geometry turbocharger to close. The vanes are controlled by the engine ECU to remain closed until the target boost pressure is achieved. Once the target boost pressure is achieved, the vanes are signaled to open. Once the vanes open, the system undergoes a cycle of undershooting and overshooting the target boost pressure until an acceptable margin of error exists between the actual boost pressure and the target boost pressure.
The same cycle of events occurs in conventional turbochargers equipped with a wastegate. When an engine's ECU determines that the turbocharger should spin up to a target boost pressure, the ECU signals the wastegate actuator to close the wastegate, and keep the wastegate closed until the target boost pressure is met. Once boost pressure is met, then the wastegate is signaled to open and the system undergoes a cycle of undershooting and overshooting the target boost pressure until an acceptable margin of error exists between the actual boost pressure and the target boost pressure.
In addition to the variable geometry vane and wastegate systems described above, control systems of this invention can be used with an electric assisted turbocharger to control the electric motor in a manner that dampens the cycle of undershooting and overshooting described above. FIG. 2 graphically illustrates the positive dampening impact that electric motor control can have, when controlled according to principles of this invention, in reducing the amount of time necessary to achieve a relatively constant/steady target boost pressure when compared to that of a conventional turbocharger as described above. Electrically damped systems of this invention can react to the same operating conditions in a shorter time and with a reduced margin of error. FIG. 3 illustrates a control scheme, according to principles of this invention, for controlling the boost pressure provided by an electric assisted turbocharger. A condition map, stored in the memory, contains target boost pressures under pre-specified sets of engine and turbocharger parameters. The microprocessor located in at least one of the engine ECU and the independent power controller receives engine and turbocharger parameters from a plurality of sensors and from the engine ECU, Box 30 . The microprocessor plots the engine and turbocharger parameters onto the stored condition map, Box 32 . The plot of engine and turbocharger parameters, yields a target boost pressure, Box 34 .
The microprocessor receives the actual boost pressure from a boost pressure sensor, Box 36 . The microprocessor determines whether the actual boost pressure is higher than the target boost pressure, Box 38 . If the actual boost pressure is less than the target boost pressure, the microprocessor uses the electric motor of the electric assist turbocharger to increase the actual boost pressure, Box 40 . Alternatively, if the actual boost pressure is not less than the target boost pressure, then the microprocessor determines whether the actual boost pressure is higher than the target boost pressure, Box, 42 . If the actual boost pressure is higher than the target boost pressure, then the microprocessor uses the electric motor of the electric assist turbocharger to lower the actual boost pressure, Box 44 .
The electric motor places a torque in the direction of turbocharger shaft rotation when the actual boost pressure is below target boost pressure. Point “A” in FIG. 2 represents a condition where the actual measured boost pressure is below a target boost pressure. In this operating condition, the independent power controller would operate the electric motor to place a torque on the turbocharger shaft in the direction of turbocharger shaft rotation, thereby causing the boost pressure to increase more rapidly toward the target boost pressure.
Likewise, when the actual boost pressure is above the target boost pressure, the electric motor applies torque opposite to the turbocharger shaft rotation. Point “B” in FIG. 2 represents an operating condition where the actual measured boost pressure is above a desired target pressure. In this operating condition, the independent power controller reverses the power to the electric motor to induce a torque opposite to the direction of turbocharger shaft rotation. This causes the boost pressure to decrease toward the target boost pressure.
The magnitude of the applied torque increases as distance from target boost pressure increases. Thus, the magnitude of the applied torque is higher at point B than at point C, because at point B, the actual boost pressure is farther from the target boost pressure, then at point C.
In an additional embodiment of the present invention, the electronic damping of the boost pressure cycle, involves anticipating the overboost associated with bringing a turbocharger up to a target boost pressure. Systems that anticipate overboost, may for example be configured to open wastegate valves or variable geometry blades once a given percentage of the target boost is reached, for example 90%. Alternatively, a system anticipating overboost, may calculate the rate of boost pressure change and use the boost change rate in conjunction with the difference between the target and actual boost pressure to begin opening valves and blades. In such cases, the electronic damping system could adapt to the anticipation methods being used and still provide damping during over-boosting and under-boosting.
Having now described the invention in detail as required by the patent statutes, those skilled in the art will recognize modifications and substitutions to the specific embodiments disclosed herein. Such modifications are within the scope and intent of the present invention. | System for controlling an electric assisted turbocharger comprise an electric motor disposed within turbocharger, and an electric motor controller electrically coupled thereto for purposes of controlling the same. A memory is electrically coupled to the electric motor controller and is configured with a condition map that correlates electric motor instructions with engine and turbocharger conditions. The system includes sensors that are electrically coupled to the electric motor controller, and that are configured to sense conditions of at least one of the turbocharger and the internal combustion engine that is coupled thereto. The electric motor controller is configured to control the electric motor based upon the input received from the plurality of sensors as compared to the data contained multi-dimensional condition map. The system provides electric motor speed control, boost pressure control dampening, and can be used to produce electricity from the electric motor depending on the particular operating condition. | 5 |
BACKGROUND OF THE INVENTION
Machines for laying bricks or other masonry modules are known in the prior art in varying forms. Generally speaking, such prior art machines have not been widely accepted commercially for economic reasons. Most of the proposed machines are complex and very costly in terms of initial manufacturing and installation and dismantling on the construction site. They require frequent adjustment and are quite sensitive in terms of their abilities to place the masonry modules properly.
Some examples of the known patented prior art are contained in U.S. Patents Re: Nos. 28,305; 2,523,063; 3,231,646; 3,328,859; 3,466,883; 3,550,344 and 3,863,420.
In general, the objective of the present invention is to improve on the prior art by providing a greatly simplified and much more practical and economical apparatus for placing masonry modules, such as bricks or concrete blocks, in successive courses for the purpose of constructing building walls of any desired perimeter shape, such as circular, square or rectangular.
Among the specific features and advantages of the invention are the ease with which the apparatus may be loaded with masonry modules at one loading station, the module transport and loading frame being rotatable relative to this station; and the relative ease with which the apparatus can be set up or dismantled at the job site, in contrast to the more complex prior art.
Additional features of the invention reside in a unique and simplified system for supporting and leveling the module transport and placement frame, and the construction of this frame including the provision of withdrawable temporary support pins for the modules being carried by the frame.
Another feature of simplicity and convenience is the provision of a cable suspension system for the module placement frame and winch means for raising and lowering the frame relative to a central upstanding support mast whose angularity can be adjusted with convenience to precisely level the module placement frame.
The entire apparatus is unitized in its assembled use condition and is symmetrical around the center support mast and ground anchoring means generally in the sense of a rotary clothesline tree.
Other features and advantages of the invention over the prior art will become apparent during the course of the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view, partly in vertical cross section, of an apparatus for placing masonry modules embodying the invention.
FIG. 2 is a plan view of the apparatus.
FIG. 3 is a fragmentary exploded perspective view of a center vertical support mast and anchoring means.
FIG. 4 is an enlarged central vertical cross section through the mast anchoring and support sleeve and also showing mast angle adjusting means.
FIG. 4A is a partially broken away side elevational view of a modified form of the present invention.
FIG. 5 is a fragmentary exploded perspective view of the transport and placement frame for masonry modules.
FIGS. 6 and 7 are partly schematic plan views of module transport and placement frames having other perimeter shapes.
DETAILED DESCRIPTION
Referring to the drawings in detail wherein like numerals designate like parts, and directing attention first to FIGS. 1 through 5, the numeral 10 designates a vertical support sleeve for the entire apparatus which may be anchored in concrete 11 placed in a small ground excavation, so that the sleeve 10 projects well above ground level. A poured concrete foundation 12, FIG. 1, for the stable support of a building wall of any desired shape is first established. In the embodiment of the invention shown in FIGS. 1 to 5, the wall being constructed by the invention is annular. However, the apparatus is capable of constructing walls of other shapes, as will be further disclosed. FIG. 1 of the drawings also shows a first or base course of modules, such as concrete blocks 13, already set in place on the foundation 12 by the apparatus or otherwise.
The apparatus additionally comprises a vertical mast 14 constructed of hollow tubular cylindrical pipe and carrying a concentric considerably enlarged diameter hub ring 15 near its top end, including a reduced diameter upper extension 16 which may be welded to the top of the mast 14. The hub ring 15 is thus fixed to the mast 14 in spaced surrounding relation thereto.
Fixed to the hub ring 15 in circumferentailly equidistantly spaced relation are plural horizontal radial pipe booms 17. These pipe booms 17 are further supported on the vertical mast 14 by turnbuckle guy rods 18 connected by eyelets 18a to a skirt 18b on the upper end of standard 9. The pipe booms 17 receive therethrough suspension cables 19 for a masonry module transport and placement frame 20, to be fully described. The distal ends of suspension cables 19 are connected to harness cables 21, the ends of which, in turn, are secured to upstanding apertured lugs 22 on the tops of radial vertical connector plates 23 of the frame 20.
The proximal ends of the suspension cables 19 are secured to eye bolts 24 on the upper end of a vertical axis guide sleeve 25 which is slidably engaged with the mast 14 and movable therealong. The cables 19 are trained over guide sheaves 26 at the outer or proximal ends of booms 17 and over additional sheaves 27 inside of the hub ring 15, the cables 19 passing through the hollow portions of booms 17 and through holes in ring 15.
For raising and lowering the frame 20 on the mast 14 a simple winch 28 having a hand crank 29 or motor means, if preferred, is fixedly secured to the mast 14 at a convenient elevation above ground level and above the support sleeve 10. The winch 28 has two interconnected spools 30 for cables 31 which have corresponding ends secured to eye bolts 32 on the lower flange of guide sleeve 25. Thus, by paying out the cables 31 from the spools 30 simultaneously, the guide sleeve 25 slides upwardly on the mast 14 and the placement frame 20 is lowered. When the cables 31 are reeled in, the sleeve 25 is pulled downwardly on the mast 14, and the frame 20 is elevated. The arrangement is simple and very reliable. The mechanism of the winch 28 is conventional and need not be described in full detail. Pinion gears, not shown, on the shaft 33 of hand crank 29 mesh with gears 34 of the spools 30 to drive the latter in unison.
The frame 20, is a trough-like upwardly opening member, which is annular in the embodiment shown in FIGS. 1 to 5, is formed in spaced concentric vertical side wall segments 35 and 35, and these segments or sections are rigidly joined at circumferentailly equidistantly spaced points around the annular frame by the vertical radial connector plates 23 or partitions, already noted, see FIG. 5. The connector plates 23 are secured by bolts 37 to side flanges 38 on the arcuate side wall segments 35 and 36. When thus assembled, the masonry module transport and placement frame 20 is rigid and unitary. It can be easily disassembled for storage and transport.
Temporary support means for the modules 13 placed in the frame 20 between the side wall segments 35 and 36 is provided in the form of a plurality of horizontal radial rods 39 received removably within radial apertures 40 near and above the bottom edges of the frame side walls. The rods 39 have handle extensions 41 at their outer ends which facilitate pulling the support rods out of the frame 20 when the course of building modules therein has been laid or placed by the apparatus on the next underlying course in the construction of a wall.
A further important feature of the invention is the provision of a reliable and simplified means for adjusting the angle of the mast 14 in all vertical planes to level accurately the frame 20. This means is in the form of the self-aligning thrust bearing 42 rigidly secured to the bottom of the mast 14 and resting freely on the top end of support sleeve 10. Leveling gauges 43 may be provided directly on the thrust bearing 42. A reduced diameter shaft extension 44 depends from the thrust bearing 42 and is rigidly secured thereto. This shaft extension extends well into the interior of anchored sleeve 10 and is engaged by adjusting bearing segments 45 at two vertically spaced elevations near the top and bottom of the shaft extension 44 for stability. Comparatively large diameter frame 20 are quite easily rotated relative to fixed loading points for the modules 13 so that a workman at one or two loading points can fill half or the entire frame with modules very conveniently. Preferably two persons load the frame 20 from diametrically opposed positions to prevent unbalancing the load.
In FIG. 4A a second embodiment is disclosed wherein the tilt adjustment assembly is toward the upper portionof the machine. In this embodiment a mast or pipe 114 has a lower end portion removably received in an upright sleeve 110 so that its lower end rests upon concrete 111 which received sleeve 110. The upper end of mast 114 extends well above the height of the wall intended to be built, the upper end of mast 114 being provided with a butt flange 107 which carries a self-aligning thrust bearing 108 secured thereto, the bearing 108 being coaxially aligned with the mast 14. A supporting upright cylindrical standard 109 projects through and is supported solely by the bearing 108, the lower portion 114 of standard 109 being of substantially smaller diameter than mast 114 and being received within the upper end portion of mast 114. The upper end portion of standard 109 forms a rotatable extension of mast 114 and projects above bearing 108 so as to carry, by their central portions, a plurality of tangentially mounted circumferentially spaced opposed pairs of horizontally extending ring supporting struts 116a and 116b. An enlarged diameter annular hub ring 115 is carried by the ends of struts 116a and 116b in concentric relationship to standard 109.
The outer periphery of ring 115 is provided with a plurality of circumferential equally spaced internally threaded pipe couplings 117a which respectively threadedly receive the inner ends of a like number of horizontally disposed, hollow cylindrical booms 117 which radiate from hub ring 115.
As a means for incrementally adjusting the tilt, i.e. angle, of the upstanding standard 109, the mast 114, at its upper end portion is provided with a plurality of circumferentially spaced upper set screws 146a, the inner ends of which carry an annular bearing 145a within the hollow portion of mast 114. Corresponding lower set screws 146b carry a lower annular bearing 145b spaced below bearing 145a in mast 114. The bearings 145a, 145b removably receive the lower extension or end portion 144 of standard 109. By manipulation of set screws 46a, 46b, the standard 109 will be tilted within the self-aligning thrust bearing 108 which carries the weight. The embodiment of FIG. 4A includes the harness cables 119 extending over pulleys or sheaves 127 and secured to eye bolts 124 on guide sleeve 125 all in the manner of the preceeding embodiment. The sleeve 125 is, however, slidably carried by mast 114, being pulled downwardly or released upwardly by cables 131 on spools 130 of winch 128. Cables 131 are secured by eye bolts 132 to guide sleeve 125 as illustrated.
Turnbuckle wires 118 support the booms 117 from eyelets 118 in a manner similar to that illustrated for the preceeding embodiment.
The embodiment of FIG. 4A is otherwise identical to the preceeding embodiment.
In operation, it is preferable for two men to load the frame 20, the men being stationed in fixed locations 180° from each other and outwardly adjacent the frame 20. As the upwardly open frame 20 is loaded with juxtaposed modules 13 the frame 20 is rotated through 180°, in one direction or the other, until a layer or course of modules 13 has been accumulated in the frame 20.
When the frame 20 is thus loaded, it can be manipulated as previously described by use of the winch 28, or 128, to lower the building modules 13 carried by the frame 20 down onto the top of the next underlying course. Prior to placing each course of modules with the apparatus, a suitable mortar layer 47, FIG. 1, is applied to the top of the course already in place. When the frame 20 is lowered sufficiently to set the modules 13 therein on the mortar layer 47, the module support rods 39 are left in place until the mortar sets up sufficiently to support the modules. Then the rods 39 are pulled free of the frame 20 and the frame 20 can thereafter be elevated by the cable means, leaving another course of the wall modules properly placed. The holes left in the mortar by rods 47 are subsequently filled in.
It is believed that the simplicity, convenience and efficiency of the apparatus compared to the complicated prior art can now be readily understood by those skilled in the art.
While FIGS. 1 to 5 show an apparatus for constructing an annular wall, it should be understood that the invention can also be embodied in an apparatus for constructing square, rectangular or other wall perimeter shapes, merely by changing the configuration of the frame 20. Thus, FIG. 6 depicts schematically an embodiment of the invention where the module transport and placement frame 20a is square in configuration. Similarly, FIG. 7 shows another embodiment where the frame 20b is rectangular. In both cases, the frames are formed in sections or segments having flanges connected by connector plates 48 in the same manner illustrated in FIG. 5 for the connector plates 23 or annular frame 20. In all other respects, the apparatus may be identical to the embodiment shown in FIG. 1 to 5, and the shape and size of the module placement frame may be varied to meet the needs of particular applications.
It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of parts may be resorted to, without departing from the spirit of the invention or scope of the subjoined claims. | A continuous transportation and placement frame for masonry modules, such as bricks or concrete blocks is suspended by cables from the ends of circumferentially spaced booms which radiate from a central hub. In one embodiment the hub is rigidly secured to the upper end portion of an upright rotatable standard, the lower end portion of which projects a short distance into the upper end of an upright mast. Adjacent screws tilt the standard in a self-aligning bearing fixed to the upper end of the mast. A winch on the mast extends and retracts the cables. The lower end of the mast is removably carried by a sleeve embedded in concrete in the floor of the building. Removable rods in the frame releasably support the modules.
In another embodiment, the winch is on the standard and the lower end of the standard is tiltably received in the sleeve. | 4 |
BACKGROUND OF THE INVENTION
For slitting or shearing off scrap from a piece of sheet metal held on a work table, a type of shear having dual tractive cutters, as shown in U.S. Pat. No. 2,946,251 has come into common use. In this type of shear, upper and lower rotary cutters, whose edges are adjacent to each other in cutting relationship along a vertical plane of cut, are mounted on lateral shafts through forward parts of upper and lower frame portions, joined together by an upward slanting bridge part aft of the cutters. The upper frame portion lies inward of the line of cut and passes above the horizontal work surface on which the sheet to be cut is laid and clamped. At the intersection of the rotary cutters, the lower frame portion is entirely beneath the work surface level. Aft of the cutters its upper edge slants upward and aft, to overlap and join the aft lower part of the upper frame portion. This upward slanting joining part of the frame is referred to as its bridging portion.
In such prior art cutter, an electric motor is mounted onto the outer side of the lower frame portion. This motor provides power to both cutters; necessarily its diameter is large and it is mounted low. After its power is transmitted first to a gear on the lower cutter shaft, a sprocket on this shaft drives a chain which extends slantingly upward to a sprocket near the aft end of the sloping bridge juncture. The power is then transmitted to the inner side of the upper frame, and, its direction of rotation being reversed, is carried by a chain and sprocket to drive the upper rotary cutter. This is driven at the same speed as the lower rotary cutter but in an opposite sense.
One function of the upward sloping edge of the bridging part is to deflect the scrap being cut from the sheet slantingly upwards over the bridging part. To accommodate power transmission mechanism beneath the deflected scrap requires a fairly large overlap of the outer and inner frame parts, and hence a substantial upward slope angle. Especially when thicker sheets are to be cut, the need to deflect the scrap upwardly adds to the power requirement of the shear.
SUMMARY OF THE INVENTION
The principal purpose of the present invention is to minimize the slope of the bridge juncture part of the frame of such a self-propelled dual tractive shear, thus to minimize the energy required to deflect the scrap part of the sheet. Another purpose is to provide for supplying more power to such a shear and to minimize power losses in transmission. Still further purposes will be apparent from this specification.
Summarizing the invention generally, and without limitation of its scope, there is here provided a motor and power drive system in which the upper rotary cutter is powered, independently of the lower rotary cutter, by a motor whose shaft extends generally forward to a bevel gear drive to the upper cutter. In the preferred embodiment the upper motor is so mounted that its shaft is canted downward toward the bevel gear intersection, the motor having sufficient clearance to pass over the sheet metal on the table surface. By so canting the motor shaft, the permissible size of the motor is substantially increased. The lower motor, whose upper extremity is positioned lower than the slanting edge of the bridge juncture of the frame, similarly drives a 45° bevel gear set powering the lower cutter, and its shaft may, if necessary be canted upward to its bevel gear intersection.
The bridge juncture part is thus freed of the function of carrying power transmission mechanism. Its only remaining functions are to join the lower outer frame part to the upper inner frame part, and to deflect the scrap over the juncture. With its functions so minimized, its upward slope is likewise minimized, lessening the power required to deflect the scrap. Since bevel gear sets permit power to be supplied at any angle necessary for clearance, motors of adequate physical size may be used to drive both cutters. However, the total power of two motors so used is markedly less than the single motor of the prior machine.
Thus, by the decrease of slant of the bridging part and the corresponding lessening of power required to deflect the scrap portion upward, and by the use of 45° bevel gears to mount the motors at any angles required for clearance and minimize losses of power transmission to the cutter, efficiency of operation is greatly increased.
Slippage of the cutters as they grasp and cut simultaneously would seemingly be a more aggravated problem if the cutters were powered independently. In the present invention, the biting grasp exerted by the contra-rotating cutters onto the sheet metal being slit is supplemented by adding a rubber traction wheel, preferably outwardly adjacent to the upper cutter and of the same diameter, and whose width is slightly less than that of the lower cutter. The lower cutter's outer edge is a cylindrical surface. With the rubber wheel pressing elastically against the upper surface of the metal sheet being slit, and its pressure resisted by the cylindrical surface of the lower cutter, the sheet is grasped elastically and positive traction is exerted. This achieves uninterrupted forward movement of the slitting shear, without either motor overspeeding.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a rotary slitting shear embodying the present invention pivotally mounted on a carriage supported by a track along the edge of a work table, shown in phantom lines.
FIG. 2 is a side elevation thereof.
FIG. 3 is a right end view thereof.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The type of rotary slitting shear whose improvement is the subject of the present invention is utilized in connection with a work table a having a track b mounted outward of its edge and below its horizontal work surface. A shear carriage generally designated c, of the type shown in said U.S. Pat. No. 2,946,251, consists essentially of a carriage plate d supported on the track b by upper and lower flanged rollers e bracket-mounted onto the plate d. Stabilizing rollers f, similarly bracket mounted, bear against the outer surface of the track b. The carriage plate d has a pair of vertically aligned pivots g near its forward end.
The frame generally designated 10 of the present shear consists functionally of two portions: an inner upper frame portion generally designated 11 and a lower outer frame portion generally designated 12, the latter having, aft of the cutters to be described, a bridge juncture part itself generally designated 13 securing the lower frame portion 12 to the upper frame portion 11. Near its forward end, shown to the left of FIGS. 1 and 2, the lower outer frame part 12 has a pair of aligned upper and lower pivot lugs 15 with vertical bores 16 which fit onto the pivots g of the shear carriage c.
As best seen in FIG. 3, the upper inner frame portion 11 is positioned inwardly of the line of cut to be made by the shear, while the lower frame portion 12 lies outwardly of the line of cut. This upper frame portion 11 is positioned above the work table a with sufficient clearance to accommodate a sheet of metal j to be cut. The forward part of the lower outer frame portion 12 lies below the level of the horizontal work surface of the table a but its bridge juncture part 13 rises slantingly above that work surface, and is accommodated beneath the slit-off portion k of a sheet metal work piece j by its upward deflection.
The principal member of the lower frame portion 12 is an outer vertical plate 18 to whose forward end the pivot lugs 15 are secured. As seen at the left side of FIG. 2, the lugs 15 extend inwardly above and below the forward edge of a lower rotary cutter disc 20, mounted on a shaft 21 which extends through a bushing 22 the forward part of the plate 18. The bushing 22 is set in the plate 18 at such height to position the uppermost part of the cutter disc 20 for cutting sheet metal on the work table a. The plate 18 extends rearward (to the right in FIGS. 1 and 2) from the lugs 15 to provide an outer side area sufficient for mounting a motor, hereinafter described, which powers the lower rotary cutter disc 20. The plate 18 may have a lower aft extension portion 23 below the maximum diameter portion of such motor.
As seen in FIG. 2, the upper pivot lug 15 is located below the horizontal plane of the work table a. The plate 18 has, aft of the upper lug 15, an upward slanting upper edge 25 which aft of the cutter disc 20 extends above the horizontal plane of the work table a. The portion of the plate 18 above that plane is referred to as its bridge juncture part 26.
Secure to the inner surface of the plate 18 commencing aft of the cutter disc 20 is a bridge juncture insert plate 27 having a similarly slanting upper edge 28. The innermost surface of the insert plate 27 coincides substantially with the vertical plane h along which the sheet metal is to be slit, that is, substantially with the inner surface of the lower rotary cutter 20.
The bridge juncture part 13 of the lower frame portion 12 is made up of the slanting upper rear portion of the plate 18 and the insert plate 27 welded together and, above the plane of the work table surface a, welded to the inner upper frame portion 11. As illustrated in FIGS. 1 and 3, the outermost member of the upper frame portion 11 is an upper insert plate 30 whose forward edge is immediately aft of the upper rotary cutter, to be described, and whose outer vertical surface 31 lies immediately inward of and adjacent to the vertical plane of cut h. Its lower aft corner is overlapped by the upper aft part of the lower insert plate 27 and welded to it to form the wedge-like bridge juncture 13. The outer vertical surface 31 of the upper insert plate 30 abuts the cutoff scrap portion k of the slit metal as it is turned upward by the forward progress of the wedge-like juncture 13.
Mounted by secure attachment means, such as welding, to the inner surface of the upper insert plate 30 is a main upper frame plate 33. In the embodiment shown the plate 33 tapers from a narrower forward edge 34 to a rear edge 35, to provide on its inward side a planar vertical surface 36 which is not parallel to the vertical plane of cut h, but, as seen in the plan view FIG. 1, is set at a conventional toe-in angle of several degrees inwardly and aft. The plate 33 is bored perpendicular to this surface 36 to accommodate an upper cutter shaft 38 on which an upper rotary cutter 40 is mounted toed in relative to the lower rotary cutter disc 20. The upper rotary cutter disc 40 is of the same diameter of the lower rotary cutter disc 20 and, as in prior practice, is held in cutting relationship with it at the level of a sheet of metal j positioned on the work table surface a. On the outer side of the upper cutter disc 40 there is mounted an elastic rubber disc 41 of the same diameter and somewhat lesser width. Its peripheral edge overlaps a major portion of the lower cutter 20.
Spacer bushings 42, 43 are provided on the lower and upper cutter shafts 21, 38 opposite to the cutter discs 20, 40. Forty-five degree bevel gears 46, held by nuts 47, are mounted on to the ends of these shafts, to be driven by similar bevel gears 48 mounted on the shafts of gear reducers 49, 50 of lower and upper electric motors 51, 52 respectively. Conveniently the motors 51, 52 are mounted by simple lower and upper brackets 53, 54 by which the housings of the gear reducers 49, 50 are bolted to the lower outer frame plate 18 and the upper frame plate 33 respectively.
Since the expected method of mounting motors would be with their shafts horizontal, it would seem at first glance to be impossible to construct a slitter with separate motors of larger diameter than the cutter discs. However, as seen in FIG. 3, the slit off portion k of the metal sheet j will be cammed upward by forward travel of the bridge juncture part 13.
As to the upper inner motor 52, the problem of accommodating a motor larger in diameter than the cutter is solved by positioning it so that its shaft is canted downward toward the point of meshing of the bevel gears 46, 48 on the upper cutter shaft 38. Its mounting bracket 54 is therefore set to elevate the lowermost part of the motor 52, as shown in FIG. 3, to pass over the sheet metal j on the work table a.
Because the present invention reduces the size of motors required, the lower motor 51 may, as seen in FIGS. 2 and 3, be mounted with its shaft horizontal, taking advantage of the increase in height afforded by the upward slant of the edge 25. If larger motors were required, lower motor 21 would be set at an angle so that its shaft was canted upward toward the point of meshing of the bevel gears which it drives.
A simple handle 56 projecting upwardly from the forward end of the main upper frame plate 33 is used, at the start of a cut, to draw the machine on its carriage c so that the upper and lower cutters 40, 20 engage the sheet metal. Thereafter they propel themselves through it with the frame 10 pivoting slightly about the pivot g from time to time to accommodate variations in grain structure. Such pivoting is controlled by a spring 57 secured, as seen in FIGS. 1 and 3, between the aft extension 23 of the outer frame plate 18 and the carriage plate d.
Smoothness of propulsion and constancy of its speed is achieved by the tractive grasp of the rubber disc 41 which overlies the lower cutter disc 20; together they draw the shear forward by grasping the sheet metal part j just outward of the line of cut.
Electricity is supplied to the two motors 51, 52 from a power source not shown through a switch m mounted on the work table a, and through coiled electric wiring to a first junction box n on a lower motor 51 and a second junction box p on the upper motor 52. As seen in FIG. 3, the connection to the upper junction box p is carried across the aft side of the bridge juncture part 13.
With constant propulsion assured by the rubber disc 41, the geared-down cutters 20, 40 require relatively small amounts of power even for cutting relatively heavy gauge sheet metal. A major factor in reducing the power requirement is the shallow slope of the upper edges 25, 28 of the bridge juncture part 13. Using a tractive shear of the prior design, a substantial amount of power was required to cam the slit off portion of sheet metal k upward along the relatively high angle of its bridge part which carried mechanism for transmitting power to the upper cutter. In the present design the height of the bridge juncture part 13 is determined principally by the requirement of strength. Its slope may be as little as say 5°; even using thick sheet metal the slit off portion k may be cammed upward at this small angle with relatively little power. Two 1/6 horsepower motors 51, 52, transmitting their power efficiently to the cutters 20, 40 through the bevel gear sets 46, 48, shear heavy gauge sheet metal with greater success than a single one-horsepower motor of the prior construction.
This improved performance is due in part to lessened loss of power in transmission.
In the prior machine, power was transmitted through a worm gear drive as well as chains and sprockets and a reversing gear, with a substantial percentage of power loss. The present invention uses two separate bevel gear drives not merely for their efficiency and for the efficiency of the lower bridge juncture, but also to permit canting of the motor shafts and thus afford clearance for motors 51, 52 whose maximum diameter is greater than that of the cutter discs 20, 40. One would not expect that there could be substantially direct drive of rotary cutter discs by motors of greater diameter.
From this disclosure, adaptations and modifications of the concepts disclosed will be apparent to persons skilled in the design, construction, and operation of such machinery. | In that type of sheet metal shear having upper and lower rotary cutters to which power is supplied, both to cut a sheet of metal overhanging a work table edge and to propel the shear along the line of cut, unexpected capacity is achieved. The upper and lower cutters are powered each with separate motor. The cutters are driven through bevel gear sets; the upper motor is positioned with clearance above the work table, with its shaft slanting downward to the bevel gear intersection. Using the separate upper motor eliminates the transmission of power along and across the upward slanting bridge portion of the frame aft of the cutters. With this function eliminated, the bridge portion may be lower, requiring less power to deflect the scrap being cut off. With this saving of power added to the saving from using the efficient bevel gear sets, heavier gauge sheets are slit with less power than heretofore required for thinner sheets. | 8 |
PRIORITY
This application claims the benefit under 35 U.S.C. §119(a) of an application filed in the United States Patent and Trademark Office on Mar. 16, 2006 and assigned Ser. No. 60/782,626 and an application filed in the Korean Intellectual Property Office on Oct. 24, 2006 and assigned Serial No. 2006-103696, the entire disclosure of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to a multi-antenna system using a closed-loop scheme, and more particularly to a method for transmitting/receiving feedback information in a multi-antenna system supporting multiple users, and a feedback system supporting the same.
2. Description of the Related Art
In wireless channel environments, as opposed to wired channel environments, reliability may be low due to multipath interference, shadowing, propagation attenuation, time variant noise, interference, and the like. There is a problem in that a data transmission rate may not increase due to the low reliability in mobile communication environments.
To overcome these problems, a multiple-input multiple-output (MIMO) system has been proposed. The MIMO system is a representative example of a multi-antenna system.
The multi-antenna system supports a single-user mode and a multi-user mode. In the single-user mode, data is transmitted to the same user via multiple transmit antennas. In the multi-user mode, data is transmitted to multiple users via multiple transmit antennas.
The multi-antenna system is divided into a closed-loop scheme in which resource allocation depends on feedback information, and an open-loop scheme independent of the feedback information. To transmit the feedback information in the multi-antenna system using the closed-loop scheme, a full feedback scheme and a single feedback scheme are present.
When precoding is used, the full feedback scheme is a scheme in which each user feeds back information regarding all transmission rates mapped to all column vectors within a codebook. The full feedback scheme has superior performance in terms of resource allocation, but is disadvantageous since there is a large amount of feedback information. When the feedback information to be generated increases, not only system complexity may increase, but also an amount of resources required to transmit the feedback information may increase.
When precoding is used, the single feedback scheme is that in which each user feeds back only index information of a column vector having a highest transmission rate. The single feedback scheme may reduce an amount of feedback information. However, it is difficult to expect optimal resource allocation in the single feedback scheme.
In the multi-antenna system using the closed-loop scheme as described above, an important problem is to provide a scheme for efficiently allocating resources on the basis of minimum feedback information. In particular, it is urgent to provide a scheme for transmitting optimal feedback information while taking into consideration an operating mode, a feedback scheme, and the like, in the multi-antenna system.
SUMMARY OF THE INVENTION
An aspect of the present invention is to address at least the above problems and/or disadvantages and to provide at, least the advantages described below. Accordingly, an aspect of the present invention is to provide a method for receiving feedback information when the feedback information mapped to an operating mode is transmitted in a multi-antenna system using a closed-loop scheme, and a feedback system supporting the same.
A further aspect of the present invention is to provide a method for receiving feedback information when the feedback information mapped to a feedback scheme is transmitted in a multi-antenna system using a closed-loop scheme, and a feedback system supporting the same.
A still further aspect of the present invention is to provide a method for generating transmission parameters based on feedback information while taking into consideration an operating mode, a feedback scheme, and the like, and transmitting data based on the transmission parameters in a multi-antenna system using a closed-loop scheme, and a feedback system supporting the same.
In accordance with an aspect of the exemplary embodiments of the present invention, there is provided a method for transmitting feedback information in a receiver of a multi-antenna system using a closed-loop scheme supporting multiple users, including selecting a feedback protocol scenario based on a communication environment from a plurality of feedback protocol scenarios; generating feedback information mapped to the selected feedback protocol; and providing a transmitter with the generated feedback information using the selected feedback protocol scenario.
In accordance with another aspect of the exemplary embodiments of the present invention, there is provided a method for receiving feedback information in a transmitter of a multi-antenna system using a closed-loop scheme supporting multiple users, including selecting a feedback protocol scenario based on a communication environment from a plurality of feedback protocol scenarios; and receiving feedback information from a receiver using the selected feedback protocol.
In accordance with a further aspect of the exemplary embodiments of the present invention, there is provided a feedback system for use in a multi-antenna system using a closed-loop scheme supporting multiple users, including a receiver for selecting a feedback protocol scenario based on a communication environment from a plurality of feedback protocol scenarios, generating feedback information mapped to the selected feedback protocol, and transmitting the generated feedback information using the selected feedback protocol scenario; and a transmitter for selecting a feedback protocol scenario based on a communication environment using the feedback information received from the receiver and allocating transmission parameters mapped to the selected feedback protocol scenario.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a block diagram illustrating a multi-antenna system using a closed-loop scheme supporting multiple users in accordance with an exemplary embodiment of the present invention;
FIG. 2 is a block diagram illustrating a structure of a transmitter in accordance with an exemplary embodiment of the present invention;
FIG. 3 is a process flowchart illustrating first to third feedback scenarios in accordance with an exemplary embodiment of the present invention;
FIG. 4 is a process flowchart illustrating a fourth feedback scenario in accordance with an exemplary embodiment of the present invention;
FIG. 5 is a process flowchart illustrating a fifth feedback scenario in accordance with an exemplary embodiment of the present invention;
FIG. 6 is a process flowchart illustrating a sixth feedback scenario in accordance with an exemplary embodiment of the present invention;
FIG. 7 is a process flowchart illustrating a seventh feedback scenario in accordance with an exemplary embodiment of the present invention; and
FIG. 8 is a process flowchart illustrating an eighth feedback scenario in accordance with an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Exemplary embodiments of the present invention will be described in detail herein below with reference to the accompanying drawings. The matters defined in the description such as a detailed construction and elements are provided to assist in a comprehensive understanding of exemplary embodiments of the invention. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. Also, descriptions of well-known functions and constructions are omitted for clarity and conciseness.
A scheme for generating feedback information through various feedback scenarios in a multi-antenna system using a closed-loop scheme in accordance with exemplary embodiments of the present invention will be described. Moreover, a scheme for generating transmission parameters based on received scenario-by-scenario feedback information in accordance with exemplary embodiments of the present invention will be described.
First, parameters used in the exemplary embodiments of the present invention are defined as follows.
M t : Number of transmit antennas
L: Number of codebooks in one code set
N: Number of precoding matrices in one codebook
M: Number of precoding vectors in a given precoding matrix
Q: Number of bits for channel quality information (CQI)
Hereinafter, exemplary embodiments of the present invention will be described with reference to the above-defined parameters and the accompanying drawings.
FIG. 1 is a block diagram illustrating a multi-antenna system using a closed-loop scheme supporting multiple users in accordance with an exemplary embodiment of the present invention.
Specifically, FIG. 1 illustrates an example of the multi-antenna system constructed with one transmitter 110 and multiple receivers 120 - 1 to 120 -N. It can be assumed that the transmitter 110 is a Node B and the multiple receivers 120 - 1 to 120 -N are user equipments (UEs). An operation based on one receiver 120 - 1 will be described below. Of course, the operation can be equally applied to the other receivers.
Referring to FIG. 1 , a channel estimator 122 - 1 of the receiver 120 - 1 estimates a channel using a signal received via at least one receive antenna. When the channel is estimated, the channel estimator 122 - 1 acquires CQI from the estimated channel. The acquired CQI is mapped to data streams of column vectors of each precoding matrix. The CQI can be expressed by CQI values. That is, the channel estimator 122 - 1 measures CQI values based on precoding matrices or precoding vectors through the channel estimation.
A feedback information generator 124 - 1 of the receiver 120 - 1 generates feedback information based on the measured CQI values in at least one feedback protocol scenario. The generated feedback information can be constructed with optimal information in a target feedback protocol scenario. The feedback protocol scenarios to be considered in the feedback information generator 124 - 1 will be described in detail below. To generate the feedback information, a codebook is predefined between the transmitter and the receiver in the multi-antenna system.
As proposed in exemplary embodiments of the present invention, all the receivers 120 - 1 to 120 -N generate feedback information and send the generated feedback information to the transmitter 110 .
A feedback information processor 114 of the transmitter 110 receives feedback information from all the receivers 120 - 1 to 120 -N. The feedback information processor 114 selects at least one user (or receiver) and at least one unitary matrix for precoding using the received feedback information. The unitary matrix for precoding is selected by the feedback information from each receiver.
The feedback information processor 114 provides a signal transmitter 112 with information regarding at least one selected receiver and at least one selected unitary matrix. The signal transmitter 112 transmits to at least one selected receiver data streams via multiple transmit antennas after precoding the data streams to be transmitted on the basis of at least one selected unitary matrix.
FIG. 2 is a block diagram illustrating a structure of the transmitter in accordance with an exemplary embodiment of the present invention.
Referring to FIG. 2 , a feedback information controller 210 receives feedback information from multiple receivers and controls an overall operation for transmitting data streams using the received feedback information. The feedback information processor 114 of FIG. 1 can be constructed with the feedback information controller 210 and a precoder allocator 240 .
Under control of the feedback information controller 210 , a selector 220 selects a single user in spatial division multiplexing (SDM) in a single-user-multiple input multiple output (SU-MIMO) mode and selects at least two users in spatial division multiple access (SDMA) in a multi-user-MIMO (MU-MIMO) mode. That is, the selector 220 selects whether to transmit streams to single or multiple receivers.
Under the control of the feedback information controller 210 , the selector 220 allocates data streams to be transmitted and subchannels on which the data streams are transmitted. Moreover, the selector 220 determines a modulation and coding scheme (MCS) level for a data transmission, a precoder and a rank. The selector 220 outputs the data streams to be transmitted to the selected receiver(s) and provides the precoder allocator 240 with information regarding the precoder and the rank. The precoder allocator 240 generates control information required for precoding the data streams to be transmitted and outputs the control information to precoders 250 .
MCS units 230 encode the data streams at optimal coding rates and modulate the encoded data (bit) streams in optimal modulation schemes. For this, the feedback information controller 210 controls the MCS units 230 . The MCS units 230 are constructed with multiple MCSs on a data stream-by-data stream basis.
The precoders 250 use predefined codebooks for precoding. To design the codebooks to be used for the precoders 250 , various schemes have been proposed. Typically, a fast Fourier transform (FFT) precoder, a Givens precoder and a Grassmannian precoder are provided. Since the codebook design schemes are well known, a description is omitted.
The precoders 250 precode the data streams output from the MCS units 250 using the designed codebooks. Precoding matrices based on the codebooks are selected by the control information provided from the precoder allocator 240 . Inverse fast Fourier transform (IFFT) and cyclic prefix (CP) units 260 and 270 transform modulated symbol streams output through precoding according to IFFT processes and insert CPs into the transformed streams. The streams are transmitted via at least one transmit antenna.
FIG. 3 is a process flowchart illustrating first to third feedback scenarios in accordance with an exemplary embodiment of the present invention.
In the first feedback scenario, receivers provide a transmitter with precoding matrices. The precoding matrices provided to the transmitter include all measured CQI values based on beamforming vectors constructing each precoding matrix. In this case, the size of the feedback information is defined by (Q×M×N). CQI values for all the precoding matrices are fed back. Thus, the first feedback scenario has the highest overhead among all possible scenarios.
In the second feedback scenario, a receiver selects one of precoding matrices constructing a codebook and provides CQI values based on the selected precoding matrix as the feedback information. In this case, the size of the feedback information is defined by (┌log 2 (N)┐+QM), where ┌n┐ indicates the smallest integer greater than or equal to n. The feedback information includes a precoding matrix index defined by ┌log 2 (N)┐ and CQI values based on the selected precoding matrix defined by QM. Thus, the second feedback scenario has less overhead than the first feedback scenario.
In the third feedback scenario, a receiver provides a single beamforming vector of a precoding matrix selected from a given codebook and a CQI value based on the single beamforming vector as the feedback information. In this case, the size of the feedback information is defined by (┌log 2 (N)┐+┌log 2 (M)┐+Q). The feedback information includes a precoding matrix index defined by ┌log 2 (N)┐, a precoding vector index of the selected precoding matrix defined by ┌log 2 (M)┐, and a CQI value based on the selected precoding vector defined by Q. The third feedback scenario has less overhead than the second feedback scenario.
As illustrated in FIG. 3 , the receiver measures a channel response through channel estimation (step 310 ). The receiver selects a precoding matrix and/or a beamforming vector(s) on the basis of a given codebook (step 312 ).
The receiver computes CQI values based on the precoding matrix and/or the beamforming vector(s) selected in step 312 (step 314 ). The receiver generates feedback information including the computed CQI values and indices of the selected precoding matrix and/or the selected beamforming vector(s). The generated feedback information is sent to the transmitter.
Upon receiving the feedback information, the transmitter allocates transmission parameters using the received feedback information (step 316 ). The transmission parameters include those related to a user, stream, subchannel, precoder, rank, and MCS.
FIG. 4 is a process flowchart illustrating a fourth feedback scenario in accordance with an exemplary embodiment of the present invention.
In the fourth feedback scenario, a receiver selects at least one operating mode between MU-MIMO mode supporting multiple users and SU-MIMO mode supporting a single user, on the basis of the number of users. The operating mode is selected on the basis of a temporarily stored active user set in a cell. The selected operating mode can be indicated by L2 signaling. The receiver can generate different feedback information between the operating modes.
When the operating mode is set to the SU-MIMO mode, the size of the feedback information is defined by
( ⌈ log 2 ( N ) ⌉ + ⌈ log 2 ( M ) ⌉ + ⌈ log 2 ( M t M ) ⌉ + QM ) .
The feedback information includes a precoding matrix index defined by ┌log 2 (N)┐, a rank selection value defined by ┌log 2 (M)┐, a precoding vector index of a selected precoding matrix defined by
⌈ log 2 ( M i M ) ⌉ ,
and a CQI value(s) based on a selected precoding vector(s) defined by
QM · log 2 ( M t M )
is a combination function
M t ! M ! ( M t - M ) ! .
As described above, the rank is selected on the basis of beamforming vectors. The number of CQI values depends on the rank.
In addition, when the operating mode is set to the MU-MIMO mode, the above-described first to third feedback scenarios can be applied. Assuming that the second feedback scenario is applied, the size of the feedback information is defined by (┌log 2 (N)┐+QM). The feedback information includes a precoding matrix index defined by ┌log 2 (N)┐ and CQI values based on a selected precoding matrix defined by QM.
As illustrated in FIG. 4 , the receiver determines whether the operating mode to be supported is the SU-MIMO or MU-MIMO mode (step 410 ). The operating mode can be identified by L2 signaling.
If the SU-MEMO mode is supported, the receiver generates feedback information (step 412 ). The generated feedback information is constructed with precoding matrix index, a beamforming vector index, a rank selection value, and CQI values. Otherwise, if the MU-MIMO mode is supported, the receiver generates feedback information based on a precoding matrix index and CQI values (step 414 ). The receiver transmits to the transmitter the feedback information generated in step 412 or 414 .
The transmitter allocates transmission parameters using the feedback information received from the receiver (step 416 ). The transmission parameters include at least one parameter related to a user, stream, subchannel, precoder, rank and MCS.
FIG. 5 is a process flowchart illustrating a fifth feedback scenario in accordance with an exemplary embodiment of the present invention.
The fifth feedback scenario is used in only the SU-MIMO mode. A receiver selects one of slow feedback signaling and fast feedback signaling. The receiver generates feedback information using a rank selection index and a codebook index in the slow feedback signaling and generates feedback information using only a precoding matrix in the fast feedback signalling.
In the slow feedback signaling, the generated feedback information has the size of (┌log 2 (M L )┐+┌log 2 (L)┐). The feedback information includes a rank selection index defined by ┌log 2 (M L )┐ and a codebook index defined by ┌log 2 (L)┐.
In the fast feedback signaling, the generated feedback information has the size of (┌log 2 (N)┐+QM L ). The feedback information includes a precoding matrix index defined by ┌log 2 (N)┐ and a CQI value(s) based on a selected precoding matrix defined by QM L , that is, (Q×1) to (Q×M).
As illustrated in FIG. 5 , the receiver selects one of a slow feedback and a fast feedback on the basis of a feedback information rate. If the slow feedback mode is selected, the receiver generates feedback information with a rank selection index and a codebook index and sends the generated feedback information to the transmitter (step 510 ). Otherwise, if the fast feedback mode is selected, the receiver generates feedback information with a precoding matrix index and a CQI value(s). The generated feedback information is sent to the transmitter (step 512 ).
When receiving the feedback information generated in step 510 or 512 , the transmitter allocates transmission parameters using the received feedback information (step 514 ). The allocated transmission parameters include at least one parameter related to a user, stream, subchannel, precoder, rank and MCS.
FIG. 6 is a process flowchart illustrating a sixth feedback scenario in accordance with an exemplary embodiment of the present invention.
The sixth feedback scenario can be applied when the SU-MIMO and MU-MIMO modes are dynamically selected. A receiver generates the feedback information using the best beamforming vector for the SU-MIMO mode and generates the feedback information using a rank and beamforming vectors for the MU-MIMO mode.
The size of the generated feedback information is defined by (┌log 2 (N)┐+┌log 2 (M)┐+Q+┌log 2 (M)┐+Q) to (┌log 2 (N)┐+┌log 2 (M)┐+Q+┌log 2 (M)┐+QM). The feedback information includes a precoding matrix index defined by ┌log 2 (N)┐, a precoding vector index of a selected precoding matrix defined by ┌log 2 (M)┐, a CQI value based on a selected precoding vector defined by Q, a rank selection index defined by ┌log 2 (M)┐, and a CQI value(s) based on a selected rank defined by QM, that is, (Q×1) to (Q×M).
Referring to FIG. 6 , the receiver measures a channel response through channel estimation (step 610 ). Using the measured channel response, the receiver generates feedback information based on a precoding matrix, a beamforming vector and CQI in an SDMA scheme (for selecting at least two users in MU-MIMO mode) and generates feedback information based on a rank and CQI in an SDM scheme (for selecting a single user in SU-MIMO mode) (step 612 ). The receiver sends the generated feedback information to a transmitter.
Upon receiving the feedback information generated in step 612 , the transmitter allocates transmission parameters using the received feedback information (step 614 ). The allocated transmission parameters include at least one parameter related to a user, stream, subchannel, precoder, rank and MCS.
FIG. 7 is a process flowchart illustrating a seventh feedback scenario in accordance with an exemplary embodiment of the present invention.
The seventh feedback scenario is determined by a period of feedback information. That is, a receiver supports two control-signaling schemes of a long-term feedback and a short-term feedback.
In the long-term feedback, the receiver can selectively support the SU-MIMO mode and the MU-MIMO mode. The SU-MIMO or MU-MIMO mode can be selected on the basis of a scheduled user set. In addition, the codebook selection and rank size are chosen in a period equal to a mode-switching period.
In the short-term feedback, the receiver generates feedback information using allocated CQI values and rank-based precoding vectors in the SU-MIMO made and generates feedback information using the precoding matrix and the CQI values in the MU-MIMO mode.
If the long-term feedback is performed, the size of the feedback information is defined by (1+┌log 2 (M)┐+┌log 2 (L)┐). The feedback information includes a 1-bit identifier for SU/MU-MIMO mode selection, a rank selection value defined by ┌log 2 (M)┐, and a codebook selection value defined by ┌log 2 (L)┐.
When the receiver supports the SU-MIMO mode in the short-term feedback, the size of the feedback information is defined by
( ⌈ log 2 ( N ) ⌉ + ⌈ log 2 ( M t M L ) ⌉ + QM L ) .
The feedback information includes a precoding matrix index defined by ┌log 2 (N)┐, at least one precoding vector index of a selected precoding matrix defined by
⌈ log 2 ( M t M L ) ⌉ ,
and a CQI value(s) based on a selected precoding vector(s) defined by QM L .
On the other hand, when the receiver supports the MU-MIMO mode in the short-term feedback, the size of the feedback information is defined by (┌log 2 (N)┐+QM L ). That is, the feedback information includes a precoding matrix index defined by ┌log 2 (N)┐ and CQI values based on a selected precoding matrix defined by QM L .
As illustrated in FIG. 7 , the receiver determines a feedback information period (step 710 ). When deciding to send feedback information in the long term, the receiver generates the feedback information mapped to the long term (step 712 ). At this time, the generated feedback information includes an operating mode selection bit, a rank selection value and a codebook selection value.
However, when deciding to send feedback information in the short term in step 710 , the receiver determines whether the operating mode to be supported is the SU-MIMO or the MU-MIMO mode (step 714 ). The operating mode can be indicated by L2 signaling.
When deciding to support the SU-MIMO mode in step 714 , the receiver generates the feedback information (step 716 ). At this time, the generated feedback information is constructed with a precoding matrix index, a beamforming vector index and a CQI value(s). The receiver sends the feedback information to the transmitter. When deciding to support the MU-MIMO mode, the receiver generates feedback information with a precoding matrix index and CQI values. Then, the receiver sends the generated feedback information to the transmitter (step 718 ).
When receiving the feedback information generated in step 712 , 716 or 718 , the transmitter allocates transmission parameters using the received feedback information (step 720 ). The transmission parameters include at least one parameter related to a user, stream, subchannel, precoder, rank and MCS.
FIG. 8 is a process flowchart illustrating an eighth feedback scenario in accordance with an exemplary embodiment of the present invention.
The eighth feedback scenario defines a feedback protocol taking into consideration the complexity of a receiver. This feedback protocol is divided into two modes. The two modes are a successive interference cancellation (SIC) mode and a non-SIC mode.
When the feedback protocol is in the SIC mode, the receiver generates feedback information including a precoding matrix index, a precoding vector index and CQI values. When the feedback protocol is in the non-SIC mode, the receiver generates feedback information by adding a rank selection index to the feedback information generated in the SIC mode.
When the receiver supports the SIC mode, the size of the feedback information is defined by (┌log 2 (N)┐+┌log 2 (M)┐+Q+QM L ). The feedback information includes a precoding matrix index defined by ┌log 2 (N)┐, a precoding vector index of a selected precoding matrix defined by ┌log 2 (M)┐, a CQI value based on a selected precoding vector defined by Q, and CQI values based on a selected rank defined by QM L .
When the receiver supports the non-SIC mode, the size of the feedback information is defined by (┌log 2 (N)┐+┌log 2 (M)┐+Q+┌log 2 (M)┐+QM L ). The feedback information includes a precoding matrix index defined by ┌log 2 (N)┐, a precoding vector index of a selected precoding matrix defined by ┌log 2 (M)┐, a CQI value based on a selected precoding vector defined by Q, a rank selection index (from a stream 1 to a stream M) defined by ┌log 2 (M)┐, and a CQI value(s) based on a selected rank defined by QM L .
As illustrated in FIG. 8 , the receiver determines whether a feedback is performed in the SIC or the non-SIC mode (step 810 ). When determining that the feedback is performed in the SIC mode, the receiver generates feedback information including a precoding matrix index, a beamforming vector index, a CQI value for SDMA, and a CQI value for SDM (step 812 ). The receiver sends the generated feedback information to the transmitter.
When determining that the feedback is performed in the non-SIC mode, the receiver generates feedback information including a precoding matrix index, a CQI value for SDMA, a rank selection index, and CQI values for SDM (step 814 ). The generated feedback information is sent to the transmitter.
When receiving the feedback information generated in step 812 or 814 , the transmitter allocates transmission parameters using the received feedback information (step 816 ). The transmission parameters include at least one parameter related to a user, stream, subchannel, precoder, rank and MCS.
As described above, the present invention can provide a unique feedback protocol for generating optimal feedback information while taking into consideration an operating mode, a feedback scheme, and the like, in a multi-antenna system. Moreover, the present invention can efficiently allocate resources on the basis of minimum feedback information in the multi-antenna system, thereby improving system performance.
While the invention has been shown and described with reference to certain exemplary embodiments of the present invention thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims and their equivalents. | A method for transmitting/receiving feedback information in a multi-antenna system using a closed-loop scheme supporting multiple users, and a feedback system supporting the same. Multiple feedback protocol scenarios are predefined on the basis of communication environments affecting feedback information configurations. The feedback information is transmitted in a feedback protocol scenario determined by a communication environment. The feedback information is constructed with information required by the communication environment. | 7 |
FIELD OF THE INVENTION
[0001] The present invention concerns oxygen generators. More particularly, but not exclusively, the present invention concerns portable oxygen candles that are used to provide breathable oxygen for medical use.
BACKGROUND OF THE INVENTION
[0002] Oxygen candles are well-known. Oxygen candles are devices that produce on demand a supply of oxygen by means of a chemical reaction. (The term “chemical reaction” is used herein to exclude electrolytic decomposition and other methods requiring an external source of energy.) An example of an oxygen candle is disclosed in WO 2009/030921 A2 (Molecular Products Group PLC) published 12 Mar. 2009.
[0003] A typical oxygen candle comprises a chemical core of an oxygen-containing substance, for example an alkali metal chlorate or perchlorate, in admixture with a catalyst that facilitates lower temperature decomposition of the chemical to oxygen and residual solids. The catalyst may be manganese dioxide or cobalt dioxide, for example, both of which reduce the temperature at which alkali metal chlorates decompose. The chemical core often also comprises a fuel such as iron.
[0004] A typical oxygen candle will comprise an ignition apparatus, which is used to trigger the production of oxygen by the device. The ignition apparatus may for example be a spring-loaded shaft with a head coated with a friction-ignitable substance such as phosphorus. When a supply of oxygen is required, the head of the spring-loaded shaft is driven into the surface of the chemical core. When the phosphorus on the head of the spring-loaded shaft is bought into contact with the chemical core, an exothermic reaction is generated. The exothermic reaction initiates the chemical reaction that releases the oxygen the chemical core contains. Alternatively, the ignition apparatus may be an explosive-type ignition, in which a pyrotechnic chemical reaction initiates the release of oxygen from the chemical core.
[0005] While the catalyst reduces the temperature at which the chemical reaction can occur, nevertheless the reaction is exothermic, and the exterior of the chemical core typically reaches very high temperatures of the order of 600-1200° C. For this reason the chemical core of the oxygen candle will be surrounded by insulation, and housed within a housing. Considerable efforts have been made to provide portable oxygen candles that can be safely held and used, despite the high temperatures the chemical core reaches when undergoing the chemical reaction.
[0006] It is of course desirable to reduce as much as possible the temperature of the oxygen supply provided by an oxygen candle. This is particularly the case with portable oxygen candles that are intended to provide an oxygen supply for medical purposes, in other words directly to a patient, as opposed to devices that are intended to increase the oxygen content in the air in a room, for example. One reason for this is that a medical oxygen supply will be supplied directly to the nose/mouth of the patient via an oxygen tube and face mask, so needs to be at a suitably low temperature, while a supply that is used to increase the air oxygen content will only be released generally into the air so can be at a higher temperature. Another reason is that it is desirable that standard oxygen tubing can be used, as these have a special construction that reduces the risk of them becoming blocked leading to a potential pressure increase and/or the user not receiving any oxygen at the face mask. If standard oxygen tubing can be used, special tubing does not need to be specially manufactured or stored for use with the oxygen candle. To be able to use standard oxygen tubing requires the oxygen to be supplied at a low enough temperature to not melt the standard oxygen tube.
[0007] The invention seeks to solve or mitigate some or all of the above-mentioned problems. Alternatively and/or additionally, the invention seeks to provide an improved oxygen generator.
SUMMARY OF THE INVENTION
[0008] In accordance with a first aspect of the invention there is provided an oxygen generator comprising:
[0009] a housing;
[0010] a chemical core within the housing, the chemical core being capable on ignition of producing oxygen by chemical reaction;
[0011] an ignition apparatus within the housing for igniting the chemical core;
[0012] a collection apparatus within the housing for collecting oxygen produced by the chemical core;
[0013] wherein the collection apparatus comprises a cooling chamber having an inlet through which oxygen produced by the chemical core enters into the cooling chamber, and an outlet through which oxygen in the cooling chamber leaves the cooling chamber,
[0014] and wherein the interior of the cooling chamber has at least one wall arranged in the path of oxygen flowing from the inlet to the outlet.
[0015] The oxygen expands as it passes through the cooling chamber, causing it to cool. By having walls in the path of the oxygen, its passage through the cooling chamber is delayed. This gives the oxygen a longer time to expand and cool. Further, by having the walls in the path of the oxygen, it has been found that this results in more efficient cooling than is the case if the oxygen is simply made to flow along an extended path. This allows the cooling chamber to be more compact. It has also been found that the walls do not need to be sealed in order for the efficient cooling to be achieved. The use of such a cooling chamber can in certain embodiments of the invention allow a portable oxygen generator to be provided in which the oxygen passing from the outlet is sufficiently low in temperatures, for example below 70° C., that standard oxygen tubing can be fixed to the outlet and the tubing will not melt. This is advantageous as it means that special tubing does not need to be used with the oxygen generator. This is particularly advantageous for oxygen tubing, which is manufactured with a star-shaped hole in the middle so that the oxygen it supplies will not be cut off if the tubing is sharply bent. Because of its unusual construction with a star-shaped hole, special heat-resistant oxygen tubing would be particularly expensive to provide.
[0016] Preferably, the chemical core comprises metal chlorate or perchlorate. Preferably, the chemical core further comprises a catalyst and a fuel. The catalyst may be manganese dioxide or cobalt dioxide. The fuel may be iron.
[0017] Preferably, the at least one wall defines a plurality of paths from the inlet to the outlet. Advantageously, a first path and second path of the plurality of paths are arranged so that a stream of oxygen flowing along the first path is directed into a stream of oxygen flowing along the second path. The direction of the first and second paths into each other acts to slow down the movement of the oxygen in the cooling chamber. The walls may be arranged concentrically. Advantageously, the oxygen generator comprises at least a first and a second wall having gaps on opposite sides of the cooling chamber. This forces the oxygen to travel from one side of the cooling chamber to the other as it passes through the cooling chamber, so increasing the time it takes to pass through the cooling chamber.
[0018] Advantageously, the cooling chamber is formed by a depression in a first cooling chamber piece and a corresponding depression in a second cooling chamber piece. This makes the cooling chamber easy to manufacture. An O-ring may be provided between the first cooling chamber piece and the second cooling chamber piece, to provide a gas-impermeable seal. The walls in the cooling chamber can advantageously be formed by walls extending from the inner surface of first cooling chamber piece into corresponding grooves in the second cooling chamber piece. As the walls are intended to provide a single elongated path they do not need to be completely gas-impermeable, and so no special seal is required between the walls of the first cooling chamber piece and the grooves of the second cooling chamber piece. This simplifies the construction of the cooling chamber. Preferably, the inlet is in the first cooling chamber piece, and the outlet is in the second cooling chamber piece. This allows the first cooling chamber piece to be positioned with its external surface facing the chemical core, and the second cooling chamber piece to be positioned with its external surface facing the outside of the oxygen generator, providing a simple and compact construction. Advantageously, the inlet is positioned apart from the outlet. For example, the inlet may be positioned in centre of cooling chamber, and the outlet at one edge of the cooling chamber. This again forces the oxygen to travel a further distance across the cooling chamber as it passes through the cooling chamber, so increasing the time it takes to pass through the cooling chamber.
[0019] Preferably, the outlet is arranged to be receive a standard oxygen tube pressure fitting. This means standard oxygen tubing can be used. A particular advantage of this is that if an excess of pressure builds up due, for example, to the oxygen tubing being blocked, the pressure fitting will simply be forced off the outlet, so allowing the oxygen to be released.
DESCRIPTION OF THE DRAWINGS
[0020] Embodiments of the present invention will now be described by way of example only with reference to the accompanying schematic drawings of which:
[0021] FIG. 1 is an exploded perspective view of an oxygen candle according to a first embodiment of the invention;
[0022] FIG. 2 is a cross-sectional view of the oxygen candle of the first embodiment;
[0023] FIG. 3 is a perspective view of the ignition end of the oxygen candle of the first embodiment;
[0024] FIG. 4 a is a perspective view of the top of a first cooling chamber piece of the oxygen candle of the first embodiment;
[0025] FIG. 4 b is a perspective view of the bottom of the first cooling chamber piece shown in FIG. 4 a;
[0026] FIG. 5 a is a perspective view of the top of a second cooling chamber piece of the oxygen candle of the first embodiment;
[0027] FIG. 5 b is a perspective view of the bottom of the second cooling chamber piece shown in FIG. 5 a;
[0028] FIG. 6 is a perspective view of a chemical core, ignition block and ignition block holder of the oxygen candle of the first embodiment;
[0029] FIG. 7 is a perspective view of the ignition block holder shown in FIG. 6 ;
[0030] FIG. 8 is a perspective view of the ignition block shown in FIG. 6 , with a thermal isolator and insulating disk of the oxygen candle of the first embodiment.
DETAILED DESCRIPTION
[0031] An oxygen candle in accordance with a first embodiment of the invention is now described with reference to FIGS. 1 to 8 .
[0032] An exploded view of the oxygen candle is shown in FIG. 1 , and a cross-sectional view is shown in FIG. 2 . The oxygen candle 1 comprises a tube-shaped housing 2 , and has an ignition end 1 a (the top end) and an oxygen-release end 1 b (the bottom end).
[0033] Inside the housing 1 is a cylindrical insulating body 3 , comprising top insulating block 4 and bottom insulating block 5 of solid insulating material at the top and bottom ends of the insulating body 3 , with a tube formed from further insulating material between the top 4 and bottom 5 insulating blocks. A chemical core 6 for ignition to produce oxygen is positioned within the insulating body 3 between the top 4 and bottom 5 insulating blocks. Each of the top 4 and bottom 5 insulating blocks has a central passage through which gas can pass between the chemical core 6 and the exterior of the insulating body 3 at the top and bottom ends respectively.
[0034] An ignition block holder 10 is positioned at the ignition end 1 a of the oxygen candle 1 , within the insulating body 3 between the top insulating block 4 and the chemical core 6 . An ignition block 11 , described in more detail below, is positioned within the ignition block holder 10 . For clarity, the chemical core 6 , ignition block holder 10 and ignition block 11 are shown alone in FIG. 6 . As can be seen in particular in FIG. 7 , in which for clarity the ignition block holder 10 is shown alone, the ignition block holder 10 comprises a body 10 a with a threaded inner surface, and at the bottom end a flange 10 b.
[0035] As can be seen in particular in FIG. 8 , there is further at the ignition end la of the oxygen candle 1 a thermal isolator 12 and insulating disk 13 . For clarity, the ignition block 11 , thermal isolator 12 and insulating disk 13 are shown alone in FIG. 8 . The ignition block 11 is made of brass, and has a threaded exterior surface 11 a which engages with the threaded interior 10 a of the ignition block holder 10 . The bottom end of the ignition block 11 comprises an ignition layer 11 b of phosphorus. The top end of the ignition block 11 comprises a slot 11 c, in which is positioned a thermal isolator 12 . The thermal isolator 12 is a rectangular slab of mica/polysiloxane composite containing 89% wt mica, 10% wt methyl polysiloxane, and 10% wt silicon dioxide, with dimensions roughly 20 mm by 25 mm and thickness 5 mm. The insulation disk 13 has a central slot 13 a through which the thermal isolator 12 passes.
[0036] A close-up of the ignition end 1 a of the oxygen candle 1 is shown in FIG. 3 . An ignition handle 15 is positioned within a lid portion 16 , which has a hinged lid 16 a which can cover the ignition handle 16 . The ignition handle 15 is circular with a bar passing diametrically across its centre, providing means by which the ignition handle 15 can be rotated by a user. As shown in FIGS. 1 and 2 , the ignition handle 15 is mounted upon a circular insulation block 14 . The bottom face of the circular insulation block 14 provides a slot into which the thermal isolator 12 is positioned.
[0037] At the oxygen-release end lb of the oxygen candle 1 , in contact with the bottom of the insulating body 3 , is a first cooling chamber piece 7 . A second cooling chamber piece 8 is positioned below the first cooling chamber piece 7 . An O-ring 9 is positioned between the first cooling chamber piece 7 and second cooling chamber piece 8 to create a cooling chamber as described in more detail below. The O-ring 9 creates a gas-impervious seal between the first cooling chamber piece 7 and the second cooling chamber piece 8 at the outside edge of the cooling chamber. The first cooling chamber piece 7 is shown in more detail in FIGS. 4 a and 4 b. The first cooling chamber piece 7 has on the top side shown in FIG. 4 a, in other words the side facing the insulating body 3 , a central hole 7 a. The first cooling chamber piece 7 has on the bottom side shown in FIG. 4 b a circular depression, in which there is a first circular wall 7 b arranged concentrically outside the hole 7 a, and a second circular wall 7 c arranged concentrically outside the first circular wall 7 b. Each of the first circular wall 7 b and second circular wall 7 c has a gap, arranged respectively on opposite sides of the first cooling chamber piece 7 .
[0038] The second cooling chamber piece 8 is shown in more detail in FIGS. 5 a and 5 b. The second cooling chamber piece 8 has on the top side shown in FIG. 5 a, in other words the side facing the first cooling chamber piece 7 , a circular depression corresponding to the circular depression of the first cooling chamber piece 7 . In the circular depression there is an offset hole 8 a positioned towards a side of the second cooling chamber piece 8 , a first circular groove 8 b positioned to receive the top edge of the first circular wall 7 b, and a second circular groove 8 c positioned to receive the top edge of the second circular wall 7 c. The offset hole 8 a is positioned outside the second circular groove 8 c, on the opposite side from the gap in the corresponding second circular wall 7 c. The offset hole 8 a of course passes through to the bottom side of the second cooling chamber piece 8 shown in FIG. 5 b. The second cooling chamber piece 8 is formed on the bottom side around the offset hole 8 a to provide a standard oxygen pressure valve, to receive a standard oxygen tube fitting.
[0039] Thus, as can be seen in particular in FIG. 2 , the circular depressions of the first cooling chamber piece 7 and second cooling chamber piece 8 together form a circular cooling chamber, with the first circular wall 7 b and second circular wall 7 b being positioned between the central hole 7 a in the first cooling chamber piece 7 and the offset hole 8 a in the second cooling chamber piece 8 .
[0040] Before use, the oxygen candle 1 will be provided with the ignition block 11 positioned within the ignition block holder 10 so that the ignition layer 11 b is a suitable distance away from the chemical core 6 to prevent accidental ignition, say a distance of 10 mm. The lid 16 a of the lid portion 16 will be closed, and the entire oxygen candle 1 may be provided within a material bag which can be opened at each end.
[0041] When used, oxygen tubing will be fitted to the standard oxygen pressure valve round the offset hole 8 a at the oxygen-release end lb of the oxygen candle. The oxygen tubing may be standard oxygen tubing which has a central hole of star-shaped cross-section, and may at the other end have a face mask, for example.
[0042] To ignite the oxygen candle 1 , first the lid 16 a of the lid portion 16 is opened to allow access to the ignition handle 15 . The ignition handle 15 is then rotated in a clockwise direction. This causes the circular insulation block 14 to rotate, which in turn rotates the thermal isolator 13 , which in turn rotates the ignition block 11 . As the ignition block 11 is screw-threaded within the ignition block holder 10 , the rotation causes the ignition block 11 to move towards the chemical core 6 . After a sufficient amount of rotation the ignition layer 11 b of the ignition block 11 will come into contact with the chemical core 6 . The friction of the phosphorus of the ignition layer 11 b rotating against the surface of the chemical core 6 will then trigger the chemical reaction of the chemical core 6 .
[0043] As mentioned above, the chemical reaction causes a considerable amount of heat. However, while the thermal isolator 13 allows rotational force to be passed from the ignition handle 15 to the ignition block 11 , due to its insulating properties it nevertheless only conducts a very small amount of heat. The insulation disk 13 and insulation block 14 further help prevent more than a very small amount of heat passing from the chemical core 6 to the ignition handle 15 , or to the ignition end 1 a of the oxygen candle generally.
[0044] As the chemical core 6 undergoes the chemical reaction, it of course releases oxygen. The oxygen is not able to pass through the insulating body 3 or the ignition end 1 a of the oxygen candle 1 , but is instead forced through the central hole 7 a of the first cooling chamber piece 7 into the cooling chamber formed by the circular depressions in the first cooling chamber piece 7 and second cooling chamber piece 8 . The oxygen first collects in the centre of the cooling chamber within the first circular wall 7 b. It then passes through the gap in the first circular wall 7 b into the area of the cooling chamber between the first circular wall 7 b and second circular wall 7 c. The oxygen then travels between the first circular wall 7 b and second circular wall 7 c in both directions from the gap in the first circular wall 7 b. The oxygen then passes through the gap in the second circular wall 7 c into the area of the cooling chamber between the second circular wall 7 c and the outside edge of the chamber, as defined by O-ring 9 between the first cooling chamber piece 7 and second cooling chamber piece 8 . Similarly to before, the oxygen then travels between the second circular wall 7 c and the outside edge of the cooling chamber in both directions from the gap in the second circular wall 7 c, until it reaches the offset hole 8 a. It then passed through the offset hole 8 a into the oxygen tubing.
[0045] As the oxygen travels through the cooling chamber from the central hole 7 a to the offset hole 8 a it expands, causing it to reduce in temperature. Importantly, the first circular wall 7 b and second circular wall 7 c do not provide a single extended path through the cooling chamber. Rather, after passing through each gap the oxygen travels in two streams in opposite directions to the other side of the cooling chamber, where the streams meet and pass through the next gap or offset hole 8 a. The meeting of the streams of oxygen arriving from opposite directions slows the passage of the oxygen through the cooling chamber, increasing the time the oxygen has to expand and cool before leaving the cooling chamber.
[0046] Whilst the present invention has been described and illustrated with reference to particular embodiments, it will be appreciated by those of ordinary skill in the art that the invention lends itself to many different variations not specifically illustrated herein. | An oxygen generator comprising a housing and a chemical core within the housing, the chemical core being capable on ignition of producing oxygen by chemical reaction. An ignition apparatus within the housing is for igniting the chemical core, and a collection apparatus within the housing collects oxygen produced by the chemical core. The collection apparatus comprises a cooling chamber having an inlet through which oxygen produced by the chemical core enters into the cooling chamber, and an outlet through which oxygen in the cooling chamber leaves the cooling chamber. The interior of the cooling chamber has at least one wall arranged in the path of oxygen flowing from the inlet to the outlet. | 2 |
BACKGROUND OF THE INVENTION
In the past when the need existed for a four wheel drive vehicle such as a tractor one had to be purchased or rented to serve the needs of the user. In the case of small farmers, ranchers, contractors and the like purchase of such a vehicle was prohibitive and most of the time not available for rent.
Further, on small ranches and farms the need for a single drive tractor is common and most users have one available and can readily obtain another like vehicle if needed. Thus, if there was some way to connect two single drive tractors in series to form a single four wheel drive vehicle, a user could have available a four wheel drive vehicle when needed by merely having access to two single axle driven tractors.
1. Field of the Invention
This invention is directed to a novel coupler for connecting in a series arrangement the back of one single axle driven tractor with the front of another single axle tractor with both tractors having their front wheels and axle assemblies removed. This novel coupling arrangement employs means for interconnecting and utilizing the leading tractor for controlling the steering mechanism of the following tractor so that the two interconnected single axle driven tractors operate in unison as a four wheel drive vehicle.
2. Description of the Prior Art
Heretofore, attempts have been made to use one or more single axle driven tractors to do a four wheel tractor job but individually and in combination these single axle driven tractors lacked the versatility of a four wheel drive vehicle. Accordingly, the need exists in industry, on the farm and ranch for a four wheel drive vehicle especially if it can be assembled from a pair of two wheel drive readily available tractors with little difficulty in combining them into a single vehicle and then reconverting them back to their individual tractor status.
SUMMARY OF THE INVENTION
In accordance with the invention claimed, a new and novel coupler is provided which makes it possible to ready connect and disconnect a pair of tractors by removing the front wheel and axle assemblies of two single wheel drive tractors and then interconnecting the rear frame of one tractor with the front frame and steering mechanism of a following tractor to provide a four wheel drive vehicle.
It is, therefore, an object of this invention to provide a novel coupler for interconnecting two single axle driven tractors into a novel four wheel vehicle.
Another object of this invention is to provide a novel coupler employing means utilizing a control mechanism of one of the tractors for controlling the steering movements of the other tractor.
A further object of this invention is to provide a novel three point hitch coupler for interconnecting a leading single axle driven tractor with a following single axle driven tractor.
A still further object of this invention is to provide a coupler which provides a three point hitch connection between the leading and following tractors utilizing the front axle housing of the following tractor.
Further objects and advantages of the invention will be apparent as the following description proceeds and the features of novelty which characterize this invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention may be more readily described by reference to the accompanying drawing in which:
FIG. 1 is a perspective view of the novel coupler of this invention interconnecting two single axle driven tractors together to form a four wheel drive vehicle.
FIG. 2 is a side view of the coupler shown in FIG. 1 with parts removed for the sake of clarity.
FIG. 3 is a top plan view of the coupler shown in FIGS. 1 and 2 with parts of each tractor and the coupler shown in dash lines illustrating their positions when the hydraulic pistons are actuated for a left turn of the vehicle.
FIG. 4 is an exploded perspective view showing the various parts of the coupler.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to the drawing by characters of reference, FIGS. 1-4 disclose a novel coupler 10 for interconnecting two rear axle driven tractors 11 and 12 into a novel four wheel drive vehicle 13. Tractors 11 and 12 are illustrated as being of the wheeled type consisting of frame 15, 15', ground contacting two rear drive wheels 16, 16', drive engines 17, 17', and driver's seats 18, 18', respectively. On the rear axle housing 19 of frame 15 of tractor 11 located inwardly of each side of the ground engaging rear wheels 16, 16 thereof, as shown in FIG. 3 is arranged a three point hitch connection forming a part of most tractors built today. This hitch is utilized as mounting points for the novel coupler disclosed for interconnecting the lead tractor 11 with the following tractor 12. The three point hitch connection on present day tractors is used for mounting most farm implements pulled or used with the tractors and is utilized herein to quickly and simply convert two, two wheel drive tractors into a four wheel drive vehicle.
The three point hitch connection comprises a pair of tie bars or side arms 22, 23 pivotally connected at one of their ends 20, 21 to tractor 11. These arms on the known tractors can be pneumatically or hydraulically lifted, lowered, or maintained at a given level by the operator of the tractor while remaining on an even level plane. When using the disclosed coupler, the arms 22, 23 are left in a position that would allow the top point of the disclosed coupler to be attached to the center hitch flange 42 of tractor 11, hereinafter described. The arms then would remain stationary while tractor 11 was used as a part of the four wheel drive vehicle created by tractors 11 and 12. The same type of three point hitch on tractor 12 will be used as the working hitch for the implements used on the newly created four wheel drive vehicle.
As noted from FIG. 3, the outer ends of the side arms 22, 23 are provided with bearing surfaces 24, 25 within which are pivotally mounted on the turned down ends 26, 27 of a shaft 28 forming part of a coupler 29. A pair of braces 30, 31 are pivotally mounted on the frame or back axle housing of tractor 11 one adjacent each pivotal point 20, 21 and fixedly connected to side arms 22, 23 to give added rigidity and to prevent side sway motion of the coupler, thereby firmly latching the two ends of shaft 28 of coupler 29 when coupler 29 interconnects the two tractors into a single vehicle.
A pair of actuating cylinders 32, 33 are pivotally connected by pins 34 at intermediate points along the sides of frame 15' of tractor 12 and have their piston rods 32A and 33A connected pivotally through pins 35 mounted in collars 36, 36' each of which are supported in bearing relationship one on each of the opposite ends of shaft 28 of coupler 29, as shown in FIG. 3.
The interconnecting means between frame 15 of tractor 11 and frame 15' of tractor 12 is coupler 29 which coupler comprises a first portion 38 arranged to extend substantially perpendicularly of shaft 28 toward frame 15 of tractor 11 when mounted thereon by side arms 22, 23, a second portion 39 extending substantially vertically upwardly a short distance from portion 39, and a third portion 40 extending laterally thereof terminating in an apertured flange 41 for insertion in an apertured cooperating U-shaped flange 42 on the rear portion of frame 15 of tractor 11 to form a pin connection when pin 43 is inserted through flanges 41 and 42, as shown.
Coupler 29 further comprises a connecting arm 43 one end of which is provided with a cylindrically shaped collar 44 extending laterally thereof for pivotally mounting around arm portion 39 of coupler 29. The other end of connecting arm 43 is arranged to extend through bearing surfaces 45 and 46 of the front wheel mounting 47 of tractor 12. Connecting arm 43 is held in the front wheel mounting of tractor 12 by any suitable means but is shown herein as a nut and bolt arrangement 48.
Thus, coupler 29 forms a three point connection for the interconnection of tractors 11 and 12, namely, the end connections of shaft 28 with arms 22 and 23 and the connection of portion 41 with flange 42 of tractor 11. The connections of hydraulic cylinders 32 and 33 with the ends of shaft 28 and the connection of arm 43 with the wheel mounting of tractor 12 form the balance of the coupler connection.
It should be noted that by manipulation of the controls for the actuating cylinders 31 and 32, the front end of tractor 12 may be turned to the right or left by extending or retracting their piston rods 32A and 33A in a manner well known in the art. It is to be kept in mind also that the actuating cylinders may be either hydraulic or pneumatically controlled and that the invention is merely directed to the coupler and not the means for controlling the actuating cylinders.
By way of example, the actuating cylinders 32 and 33 may be interconnected with a hydraulic system of tractor 11 and thus the operator of tractor 11 may control the operation of the movement of tractor 12 when interconnected by coupler 29 disclosed herein. It should be noted that although actuating cylinders have been disclosed for moving the following tractor 12 with respect to the leading tractor 11, other suitable turning means may be utilized. For example, collar 44 may be formed by a suitable motor such as a centrifugal or other form of pivotal motor mounted at this point to provide a turning torque for movement of arm 40 relative to connecting arm 43 of coupler 29 to move the front end of tractor 12 relative to tractor 11 to provide the necessary following movement of tractor 12. Thus, suitable fluid or electrical controls 50 can be used by the operator of tractor 11 to control tractor 12. Dual controls must also be provided for controlling the engine operation of tractor 12 and its wheel driving function by the operator of tractor 11 in order to provide a unitary operating four wheel drive vehicle.
It should be noted that the longitudinal movement of collar 44 along arm portion 39 of coupler 29 should be limited and this can be accomplished by any suitable means, such as pins or flanges on arm portion 39. By limiting the movement of collar 44, compensation is provided for the missing front of tractor 11 thereby aiding in balancing the weight of the assembled four wheel drive vehicle 13.
Further, it should be noted that the relative lengths of the various arms of the tractors may be changed to fit the needs of the particular tractors being assembled into a single vehicle. Still further, for some particular model tractors the arm 38 of the coupler 29 may be omitted with arm portion 39 extending laterally from shaft 28.
To connect tractors 11 and 12 together, the coupler 29 is first attached to its three point hitch connection formed by side arms 22, 23 and the flange 42. Tractor 12 is then jacked up and its front axle removed. Tractor 11 is then backed into cooperating relationship with tractor 12 so that connecting arm 43 may be extended into the front wheel housing 47 of tractor 12 to thereby connect connecting arm 43 of coupler 29 to frame 15' of tractor 12.
Although but a few embodiments of the invention have been shown and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims. | A coupler for detachably connecting two back axle power driven front wheelless tractors together in series to form a single four wheel drive vehicle. | 1 |
[0001] This application claims priority to Korean Patent Application No. 2002-36626, filed on Jun. 28, 2002, the contents of which are herein incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a content addressable memory cell (hereinafter referred to as “CAM cell”) and, more particularly, to a ternary content addressable memory cell (hereinafter referred to as “TCAM cell”) capable of storing three states of information.
[0004] 2. Discussion of Related Art
[0005] A CAM is a memory which is addressed by its own contents. Different from a RAM or ROM wherein an address is used to indicate a specific position in its memory cell array and outputs data stored in the addressed position, a CAM is externally supplied with data, and searches are made within the contents of the CAM for a match with the supplied data, and outputs an address depending on a comparison result. Each cell of a CAM includes comparison logic. A data value input to the CAM is compared with data stored in all the cells simultaneously. The matched result is the address. A CAM is commonly used in applications requiring fast searches for a pattern, a list, image data, etc.
[0006] A CAM cell may be classified into a binary CAM cell and a TCAM cell. A typical binary CAM cell is configured with a RAM cell to store one of two states of information, i.e., a logic “1” state and a logic “0” state. The binary CAM cell includes a compare circuit that compares data supplied externally (hereinafter, ‘comparand data’) with data stored in the RAM cell and drives a corresponding match line to a predetermined state when the comparand data and the stored data are matched. Examples of the binary CAM cells are disclosed in U.S. Pat. No. 4,646,271 entitled “CONTENT ADDRESSABLE MEMORY HAVING DUAL ACCESS MODE”, U.S. Pat. No. 4,780,845 entitled “HIGH DENSITY, DYNAMIC, CONTENT-ADDRESSABLE MEMORY CELL”, U.S. Pat. No. 5,490,102 entitled “LOW CAPACITANCE CONTENT-ADDRESSABLE MEMORY CELL”, and U.S. Pat. No. 5,495,382 entitled “CONTENTS ADDRESSABLE MEMORY”.
[0007] A TCAM cell can store one of three states of information, i.e., a logic “1” state, a logic “0” state, and a “don't care” state. The TCAM cell includes a main RAM cell to store one of two states of information, i.e., a logic “1” state or a logic “0” state, and a mask RAM cell to store local mask data. A comparison result of comparand data with data stored in the main RAM cell is masked with the mask data such that the comparison result does not affect a corresponding match line. Such a TCAM cell offers the user more flexibility to determine what data bits in a word will be masked during a compare operation. TCAM cells are further described, for example, in U.S. Pat. No. 6,044,055 entitled “CONTENT ADDRESSABLE MEMORY STORAGE DEVICE” and U.S. Pat. No. 6,514,384 entitled “TERNARY CONTENT ADDRESSABLE MEMORY CELL”. FIG. 1 shows a conventional TCAM cell which includes a main memory cell having two NMOS transistors T 1 and T 2 and two inverters INV 1 and INV 2 , a compare circuit consisting of three NMOS transistors T 3 , T 4 , and T 5 , a mask circuit consisting of an NMOS transistor T 6 , and a mask memory cell consisting of two NMOS transistors T 7 and T 8 and two inverters INV 3 and INV 4 . The TCAM cell shown in FIG. 1 is described in U.S. Pat. No. 6,154,384. Signal lines represented as “BL” and “BLB” are used for data transmission of a main memory cell. Signal lines represented as “CL” and “CLB” are used for comparand data transmission. Signal lines represented as “ML” and “MLB” are used for mask data transmission of a mask memory cell. A TCAM is made from TCAM cells arranged in a matrix of rows and columns. TCAM cells in a row constitute one word, which may be 32, 64, 128 bits, or higher. Transistors T 5 and T 6 of the respective TCAM cells in a row constitute a wired-OR logic for a match line MATCH.
[0008] Although TCAMS afford advantages such as speedy access for numerous applications, drawbacks do exist. For example, when comparand data of the TCAM cell of FIG. 1 is not matched with data stored in a main memory cell, a discharge operation of a match line is carried out. Because the occurrence of unmatched words is usually greater than the occurrence of matched words, match lines (MATCH) corresponding to the unmatched words are frequently discharged, and more power is thereby consumed.
[0009] Another problem is shown in FIG. 2A. A logic high level at node DX of FIG. 1 (VCL-Vtn4 or VCLB-Vtn3, wherein VCL represents a voltage of a CL line, VCLB represents a voltage of a CLB line, and the Vtn3 and Vtn4 represent threshold voltages of transistors T 3 and T 4 , respectively) approaches a voltage only slightly higher than the threshold voltage of transistor T 3 or T 4 . This high level voltage at DX is used to turn on transistor T 5 . To compensate for the lowered high voltage level, a big-sized transistor T 5 must be used. The need for a bigger size transistor in each cell lowers the overall density of the TCAM. Even more problematic, if an operation voltage is lowered, the TCAM cell may not operate properly as the high level voltage at DX fails to meet the threshold voltage of transistor T 5 . For illustration, assuming that an operation voltage is 1.2V and a threshold voltage of an NMOS transistor T 5 is 0.5V, a high level of the DX node thus becomes 0.7V, as shown in FIGS. 2A and 2B. Since this level is not high enough to turn on the NMOS transistor T 5 , the signal level on match line MATCH cannot be used to properly indicate a match or no-match.
[0010] Referring back to the TCAM cell of FIG. 1, if the compare result is not masked (by transistor T 6 ), transistor T 5 is turned off when comparand data is matched to data stored in a main memory cell and is turned on when there is no match. That is, when there is a match, a match line MATCH is maintained at a precharge state. When there is no match, charges of the match line are discharged through transistors T 5 and T 6 . The discharge speed of the match line MATCH is a function of the number of unmatched bits in one word. For example, when only one bit of one word is unmatched, the charges of the match line MATCH are discharged through the transistors T 5 and T 6 of the unmatched TCAM cell. When n bits are unmatched among an m-bit word (n being a positive integer smaller than m), the charges of the match line MATCH are discharged through transistors nx (T 5 , T 6 ) in n TCAM cells. The time needed to discharge the match line MATCH varies depending on the number of mismatched cells. To minimize the discharge speed variation, larger sized transistors T 5 and T 6 are needed. This, however, results in larger size TCAM cells. Therefore, a discharge speed difference also negatively affects the density of a TCAM.
[0011] In view of the foregoing, a need exists for a content addressable memory cell that is stably operable at low operation voltage, low power consumption, and facilitates manufacture of a high density CAM.
SUMMARY OF THE INVENTION
[0012] According to an aspect of the present invention, a ternary content addressable memory (TCAM) having an array of cells arranged in rows and columns is provided, each cell comprising: a main memory cell for storing a data bit and its complement and a pair of bit lines for carrying the data bit and its complement; a compare circuit having a pair of compare lines and an output node, the compare circuit coupled to the main memory cell for comparing the data bit and its complement with corresponding compare lines and outputting a compared signal at the output node; a match circuit coupled to the output node of the compare circuit and a match input line and a match output line, the match circuit for selectively connecting the match input line to the match output line based on the compared signal; a mask memory cell for storing and outputting mask data; and a mask circuit coupled to the match circuit and the match input line and the match output line for masking the compared signal or for selectively connecting the match input line to the match output line based on the mask data.
[0013] Preferably, the compare circuit includes a pair of PMOS transistors, and the pair of PMOS transistors are correspondingly coupled to the pair of compare lines and commonly connected at the output node of the compare circuit. Further, each of the match circuit and the mask circuit includes an NMOS transistor, wherein the NMOS transistors of the match circuit and the mask circuit are commonly connected at the match input line and the match output line. In one embodiment, the match input line is connected to the match output line upon an indication of a match from the compared signal.
[0014] According to another aspect of the invention, the match input line is connected to the match output line upon an indication of a mask condition from the mask data. The match input line is also preferably cascaded from and connected to a match output line of a preceding cell or the match output line is cascaded and connected to a match input line of a subsequent cell along the same row. The TCAM further includes a discharge circuit coupled to ground and to the match input line of the first cell of the same row and a precharge circuit coupled to a preset voltage and to the match output line of the last cell of the same row, wherein when all cells of the same row output a match, all the match input and output lines of the same row are discharged to substantially ground. According to this embodiment, the compare circuit includes a pair of PMOS and a pair of NMOS transistors, each PMOS transistor being commonly connected to a corresponding NMOS transistor and a corresponding compare line, and each of the match circuit and the mask circuit includes an NMOS transistor.
[0015] According to another aspect of the invention, each of the match circuit and the mask circuit includes a PMOS transistor, and the compare circuit includes a pair of NMOS transistors. The PMOS transistors are commonly connected at the match input line and at the match output line. The TCAM of this embodiment further includes a precharge circuit coupled to a preset voltage and to the match input line of the first cell of the same row and a discharge circuit coupled to ground and to the match output line of the last cell of the same row, wherein when all cells of the same row output a match, all the match input and output lines of the same row are precharged to substantially the preset voltage.
[0016] Preferably, the main memory cell and the mask memory cell are at least one of SRAM, DRAM, or nonvolatile memory (NVM) cells. The TCAM further includes a main word line and a mask word line which are connected to each other. Further, each of the match circuit and the mask circuit includes a PMOS transistor.
[0017] According to another embodiment of the invention, a content addressable memory (CAM) having an array of cells arranged in rows and columns is provided, each cell comprising: a main memory cell for storing a data bit and its complement and a pair of bit lines for carrying the data bit and its complement; a compare circuit having a pair of compare lines and an output node, the compare circuit coupled to the main memory cell for comparing the data bit and its complement with corresponding compare lines and outputting a compared signal at the output node; a match circuit coupled to the output node of the compare circuit and a match input line and a match output line, the match circuit for selectively connecting the match input line to the match output line based on the compared signal; a discharge circuit coupled to ground; a precharge circuit coupled to a preset voltage; the discharge circuit or the precharge circuit coupled to the match input line of the same row or the match output line of the same row, wherein when all cells of the same row output a match, all the match input and output lines of the same row are either precharged or discharged.
[0018] Preferably, the compared circuit includes a pair of PMOS transistors and the match circuit includes a NMOS transistor. According to an alternative embodiment, the compare circuit includes a pair of NMOS transistors and the match circuit includes a PMOS transistor.
[0019] Preferably, the TCAM further includes a mask circuit coupled to the match circuit and the match input line and the match output line for masking the compared signal or for selectively connecting the match input line to the match output line based on a mask data. A memory controller is further included for providing operation mode to the CAM.
[0020] A method is also provided for operating a content addressable memory (CAM) having an array of cells arranged in rows and columns, comprising the steps of: storing in a main memory cell a data bit and its complement; comparing the data bit and its complement with signals at corresponding compare lines and outputting a compared signal; selectively connecting a match input line to a match output line based on an indication of a match from the compared signal to form a match line; and setting the match line at a first voltage level when all of memory cells of the same row are matched, wherein said first voltage is a ground voltage or a power supply voltage.
[0021] These and other aspects and features of the present invention will become more apparent from the fully detailed description of preferred embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] [0022]FIG. 1 is a circuit diagram of a conventional TCAM cell.
[0023] [0023]FIG. 2A shows a voltage level of an internal node of the TCAM cell of FIG. 1 during a compare operation.
[0024] [0024]FIG. 2B shows voltage levels of internal nodes of the TCAM cell of FIG. 1.
[0025] [0025]FIG. 3 is a block diagram of a ternary content addressable memory (TCAM) according to an embodiment of the present invention.
[0026] [0026]FIG. 4 is a circuit diagram of a TCAM cell in the TCAM shown in FIG. 3.
[0027] [0027]FIG. 5 shows a voltage level of an internal node of the TCAM cell shown in FIG. 4 during a compare operation of the TCAM cell.
[0028] [0028]FIG. 6 is a circuit diagram of another embodiment of a TCAM cell in the TCAM shown in FIG. 3.
[0029] [0029]FIG. 7 is a block diagram of a ternary content addressable memory (TCAM) according to another embodiment of the present invention.
[0030] [0030]FIG. 8 is a circuit diagram of a TCAM cell in the TCAM shown in FIG. 7.
[0031] [0031]FIG. 9 is a circuit diagram of another embodiment of a TCAM cell in the TCAM shown in FIG. 7.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0032] Referring to FIG. 3, a TCAM 100 according to the present invention includes an array 120 having a plurality of TCAM cells TCCij arranged in a matrix of rows and columns having ‘i’ rows and ‘j’ columns with i=0 to m and j=0 to n, m and n being natural integers. TCAM cells in each row are commonly coupled to the same wordline. For example, TCAM cells TCC 00 -TCC 0 n in a first row are commonly coupled to a wordline WL 0 . TCAM cells TCC 10 -TCC 1 n in a second row are commonly coupled to a wordline WL 1 . TCAM cells TCCm 0 -TCCmn in an mth row are commonly coupled to a wordline WLm. The wordlines WL 0 -WLm are coupled to a decoder 140 , which selectively drives the wordlines WL 0 -WLm based on an operation mode instruction from a memory controller (not shown). For example, the decoder 140 selectively drives one of the wordlines WL 0 -WLm when storing data information in TCAM cells of any row or reading out data information therefrom. In a case where comparand data bits (constituting a search word) are compared with data bits (constituting a word) stored in TCAM cells of each row, the decoder 140 does not select all the wordlines WL 0 -WLm at the same time. TCAM cells of each row are commonly coupled to a bitline pair, a mask line pair, and a compare line pair. For example, TCAM cells TCC 00 -TCCm 0 of a first column are commonly coupled to a bitline pair BL 0 and BL 0 B, a mask line pair ML 0 and ML 0 B, and a compare line pair CL 0 and CL 0 B. TCAM cells TCC 01 -TCCm 1 of a second column are commonly coupled to a bitline pair BL 1 and BL 1 B, a mask line pair ML 1 and ML 1 B, and a compare line pair CL 1 and CL 1 B. TCAM cells TCC 0 n -TCCm n of an nth column are commonly coupled to a bitline pair BLn and BLnB, a mask line pair MLn and MLnB, and a compare line pair CLn and CLnB. A bitline pair BLi and BLiB of each column is used for transmitting data to be stored/read out to/from TCAM cells in a corresponding column. A mask line pair MLi and MLiB of each column is used for transmitting mask data to be stored/read out to/from TCAM cells in a corresponding column. A compare line pair CLi and CLiB of each column is used for transmitting comparand data.
[0033] The TCAM cell 100 according to an embodiment of the present invention includes match lines MATCH 0 -MATCHm that correspond to rows or wordlines WL 0 -WLm, respectively. Each of the match lines MATCH 0 -MATCHm is divided into a plurality of match line segments. For example, a match line MATCH 0 of a first row is divided into match line segments MATCH 00 to MATCH 0 n+ 1. A match line MATCH 1 of a second row is divided into match line segments MATCH 10 to MATCH 1 n+ 1. A match line MATCHm of an mth row is divided into match line segments MATCHm 0 to MATCHmn+1. At each row, TCAM cells are coupled between adjacent match line segments, respectively. For example, a TCAM cell TCC 00 positioned at a first row and a first column is coupled between match line segments MATCH 00 and MATCH 01 . A TCAM cell TCC 01 positioned at the first row and a second column is coupled between match line segments MATCH 01 and MATCH 02 . A TCAM cell TCC 0 n positioned at the first row and an nth column is coupled between match line segments MATCH 0 n and MATCH 0 n+ 1. TCAM cells of the other rows are arranged the same as described above.
[0034] Discharge circuits 160 D 0 , 106 D 1 , . . . , and 160 Dm are coupled to corresponding first match line segments MATCH 00 , MATCH 10 , . . . , and MATCHm 0 , each constituting match lines MATCH 0 to MATCHm, respectively. The discharge circuits 160 D 0 - 160 Dm electrically connect corresponding match line segments MATCH 00 to MATCHm 0 to a ground voltage, respectively for discharging the match lines. Precharge circuits 180 P 0 , 180 P 1 , . . . , and 180 Pm are coupled to the last match line segments MATCH 0 n+ 1, MATCH 1 n+ 1, . . . , and MATCHmn+1, respectively. The precharge circuits 180 P 0 - 180 Pm electrically connect corresponding match line segments MATCH 0 n+ 1-MATCHmn+1 to a power supply voltage, respectively. The discharge circuits 160 D 0 - 160 Dm and the precharge circuits 180 P 0 - 180 Pm operate or selectively operate based on an operation mode, preferably from a memory controller (not shown). The last match line segments MATCH 0 n+ 1-MATCHmn+1 of all rows are coupled to a match circuit 200 , which generates an address corresponding to currently inputted comparand data in response to logic states of the match line segments MATCH 0 n+ 1-MATCHmn+1.
[0035] [0035]FIG. 4 shows a preferred embodiment of one TCAM cell, e.g., TCC 00 , shown in FIG. 3. The TCAM cell includes a main memory cell and a mask memory cell. Although the main memory cell and the mask memory cell shown herein is an SRAM cell, it is apparent to one ordinary skilled in the art that other types of memory cells e.g., DRAM cell, FRAM cells, or the like can be used.
[0036] The main memory cell is coupled to a bitline pair BL 0 and BL 0 B, and includes two NMOS transistors T 10 and T 12 and two inverters INV 10 and INV 12 . When the stored data in the main memory cell is “0”, cell node CN 10 has a logic low level and cell node CN 12 has a logic high level. When the stored data in the main memory cell is “1”, the cell node CN 10 has a logic high level and the cell node CN 12 has a logic low level. The mask memory cell is coupled to a mask line pair ML 0 and MLB and a wordline WL 0 , and includes two NMOS transistors T 22 and T 24 and two inverters INV 14 and INV 16 . When the mask data stored in mask memory cell is “0”, cell node CN 14 has a logic low level and cell node CN 16 has a logic high level. When the stored mask data in mask memory cell is “1”, the cell node CN 14 has a logic high level and the cell node CN 16 has a logic low level.
[0037] The CAM cell TCC 00 further includes two PMOS transistors T 14 and T 16 and two NMOS transistors T 18 and T 20 . The PMOS transistor T 14 has a first electrode (drain or source) coupled to a complementary compare line CL 0 B, a second electrode (source or drain) coupled to an internal node DX, and a control electrode coupled to the cell node CN 10 of the main memory cell. The PMOS transistor T 16 has a first electrode (source or drain) coupled to a compare line CL 0 , a second electrode (drain or source) coupled to the internal node DX, and a control electrode coupled to the cell node CN 12 of the main memory cell. The PMOS transistors T 14 and T 16 constitute a detection circuit for detecting whether comparand data transmitted through a compare line pair is matched with data stored in the main memory cell.
[0038] The NMOS transistor T 18 has a first electrode (or source) coupled to a match line segment MATCH 00 , a second electrode (or drain) coupled to a match line segment MATCH 01 , and a control electrode coupled to the internal node DX. The NMOS transistor T 18 constitutes a match circuit that electrically connects the match segments MATCH 00 and MATCH 01 when the comparand data is matched with the data stored in the main memory cell. The NMOS transistor T 20 has a first electrode (or source) coupled to the match line segment MATCH 00 , a second electrode (or drain) coupled to the match line segment MATCH 01 , and a control electrode coupled to the cell node CN 16 of the mask memory cell. The NMOS transistor T 20 constitutes a mask circuit that electrically connects the match line segments MATCH 00 and MATCH 01 in response to the mask data stored in the mask memory cell. Although the main memory cell and the mask memory cell are coupled to the same wordline WL 0 , as shown in FIG. 4, it is apparent that the wordline may be separated into two wordline sections each for separately connecting to the main memory cell and the mask memory cell.
[0039] In the TCAM cell having the above-described structure, when the mask data is “0”, the TCAM cell TCC 00 is in an “X” or “don't care” state. When the mask data is “1”, the TCAM cell TCC 00 carries out a compare operation. More specifically, in the “X” state where the mask data is “0”, the cell node CN 14 of the mask memory cell has a logic low level and the cell node CN 16 thereof has a logic high level. In this case, the NMOS transistor T 20 is turned on and match line segments MATCH 00 and MATCH 01 are electrically connected to each other. This means the match line segments MATCH 00 and MATCH 01 are electrically connected to each other irrespective of the compare result of the comparand data with the data stored in the main memory cell. When the mask data is “1”, the cell node CN 14 of the mask memory cell has a logic high level and the cell node CN 16 thereof has a logic low level. In this case, the NMOS transistor T 20 is turned off. The match line segments MATCH 00 and MATCH 01 are electrically connected depending upon the compare result of the comparand data with the data stored in the main memory cell.
[0040] An exemplary compare function of the TCAM cell will now be described. When the stored data in the main memory cell is “0”, the cell node CN 10 of the main memory cell has a logic low level and the cell node CN 12 thereof has a logic high level. When the TCAM cell is not masked, the TCAM cell carries out a compare function. When the stored data in the main memory cell is “1”, the cell node CN 10 has a logic high level and the cell node CN 12 has a logic low level. A logic state of the internal node DX is determined depending on the compare result of the comparand data with the data stored in the main memory cell. As an illustration, when the stored data in the main memory cell is “0”, the PMOS transistor T 14 is turned on and the PMOS transistor T 16 is turned off. When “0” comparand data is transmitted through the compare line pair CL 0 and CL 0 B, a “1” data on the complementary compare line CL 0 B is transmitted to the internal node DX through the PMOS transistor T 14 . This causes the NMOS transistor T 18 to be turned on, and causes the match line segments MATCH 00 and MATCH 01 to be electrically connected to each other. On the other hand, when a “1” comparand data is transmitted through the compare line pair CL 0 and CL 0 B, a “0” data on the complementary compare line CL 0 B is transmitted to the internal node DX through the PMS transistor T 14 . This causes the NMOS transistor T 18 to be turned off, and the match line segments MATCH 00 and MATCH 01 are not electrically connected.
[0041] [0041]FIG. 5 shows a voltage level of an internal node of the TCAM cell shown in FIG. 4 during a compare operation of the TCAM cell. When the internal node DX is discharged, the voltage at DX is dropped to a threshold voltage Vtp14 or Vtp 16 of the PMOS transistor T 14 or T 16 .
[0042] When the data stored in the main memory is “1”, the PMOS transistor T 14 is turned off and the PMOS transistor T 16 is turned on. When a “0” comparand data is transmitted through the compare line pair CL 0 and CL 0 B, a “0” data on the compare line CL 0 is transmitted to the internal node DX through the PMOS transistor T 14 . This causes the NMOS transistor T 18 to be turned off, and causes the match line segments MATCH 00 and MATCH 01 to be electrically separated from each other. On the other hand, when a “1” compare data is transmitted through the compare line pair CL 0 and CL 0 B, a “1” data on the compare line CL 0 is transmitted to the internal node DX through the PMOS transistor T 14 . This causes the NMOS transistor T 18 to be turned on, and causes the match line segments MATCH 00 and MATCH 01 to be electrically connected to each other. Therefore, when comparand data is matched with data stored in the main memory cell, match line segments MATCH 00 and MATCH 01 are electrically connected to each other. On the other hand, when the comparand data is not matched therewith, the match line segments MATCH 00 and MATCH 01 are electrically separated from each other. At any row, when data bits stored in all the TCAM cells of the same row are matched with comparand data bits transmitted through corresponding compare line pairs, match line segments constituting a match line corresponding to the row are electrically connected to each other and to the corresponding discharge circuit 160 D[X]m. As a result, the match line corresponding to the row is substantially discharged to ground.
[0043] In the TCAM cell according to the invention, a first match line segment of each row is coupled to a ground voltage through a discharge circuit, and the last match line segment is coupled to a power supply voltage through a precharge circuit. The MATCH output in each row will be at the ‘precharge’ level or at ‘1’ unless there is a match from the compare of stored data of all TCAM cells in the same row, in which case the MATCH output is discharged to ‘0’. Accordingly, a logic state of a match line of each row is varied only when all data bits of each word are matched with comparand data bits. This means the logic state of the match line is varied with the same speed irrespective of the number of unmatched data bits of one word.
[0044] As previously discussed, in the convention TCAM cell structure shown in FIG. 1, if an operation voltage is dropped, the TCAM cell cannot perform a compare function. Advantageously, according to the first embodiment of the TCAM cell structure according to the present invention, a logic high level of a compare line CL 0 or a complementary compare line CL 0 B is transmitted to an internal node DX through a PMOS transistor T 14 or T 16 , without reduction of threshold voltage. Thus, the TCAM cell normally carries out a compare function even when an operation voltage is low, thereby improving reliability of the TCAM cell. Additionally, because the logic high level of the compare line CL 0 or the complementary compare line CL 0 B is transmitted to the internal node DX through the PMOS transistor T 14 or T 16 without reduction by threshold voltage, the driving capability of the NMOS transistor T 18 is improved. With improved driving capability, the NMOS transistor T 18 can be reduced in size. And, the overall density of the TCAM is higher.
[0045] Further, since the number of unmatched words is much greater than that of matched words, the conventional TCAM cell structure of FIG. 1 has a considerably higher power consumption because the logic state of a match line is varied when a mismatch arises. On the other hand, the TCAM structure according to the invention requires considerably less power consumption because a logic state of a match line is varied only when a match arises. FIG. 6 shows a circuit diagram of a TCAM cell shown according to another embodiment of the present invention. In FIG. 6 and FIG. 4, same numerals denote same components. A TCAM cell of FIG. 6 is substantially identical to the TCAM cell of FIG. 4 except that NMOS transistors T 26 and T 28 are added in the circuit of FIG. 6. An NMOS transistor T 26 has a first electrode coupled to a complementary compare line CL 0 B, a second electrode coupled to an internal node DX, and a control electrode coupled to a cell node CN 12 of a main memory cell. An NMOS transistor T 28 has a first electrode coupled to a compare line CL 0 , a second electrode coupled to the internal node DX, and a control electrode coupled to a cell node CN 10 of the main memory cell. According to such a structure, a voltage of the internal node DX fully swings from a power supply voltage to a ground voltage.
[0046] [0046]FIG. 7 shows a block diagram of a content addressable memory (CAM) according to a second embodiment of the present invention is illustrated in FIG. 7. In FIG. 7 and FIG. 3, same numerals denote same components. As shown in FIG. 7, a precharge circuit is coupled to a first match line segment of each row, and a discharge circuit is coupled to the last match line segment thereof. For example, a precharge circuit 180 P 0 ′ is coupled to a first match line segment MATCH 00 of a first row, and a discharge circuit 160 D 0 ′ is coupled to the last match line segment MATCH 0 n+ 1 thereof. A precharge circuit 180 P 1 ′ is coupled to a first match line segment MATCH 10 of a second row, and a discharge circuit 160 D 1 ′ is coupled to the last match line segment MATCH 1 n+ 1 thereof. A precharge circuit 180 Pm′ is coupled to a first match line segment MATCHm 0 of the last row, and a discharge circuit 160 Dm′ is coupled to the last match line segment MATCHmn+1 thereof. FIG. 8 is a circuit diagram of one preferred embodiment of the TCAM cell structure in the TCAM in FIG. 7. Although a TCAM cell positioned at a first row and a first column is illustrated in FIG. 8, it will be understood that the other cells in the TCAM of FIG. 7 have the same structure. The TCAM cell TCC 00 according to this embodiment of the invention includes a main memory cell and a mask memory cell. Although an SRAM cell is shown as the main memory cell and the mask memory cell, it is apparent to one skilled in the art that other memory cells e.g., DRAM cell, FRAM cell, and the like can also be used. The main memory cell is coupled to a bitline pair BL 0 and BL 0 B and a wordline WL 0 , and includes two NMOS transistors T 30 , T 32 and two inverters INV 30 and INV 32 . When the stored data in the main memory is “0”, cell node CN 30 of the main memory cell has a logic low level and cell node CN 32 has a logic high level. When the data stored in the main memory cell is “1”, the cell node CN 30 of the main memory cell has a logic high level and the cell node CN 32 thereof has a logic low level. A mask memory cell is coupled to a mask line pair ML 0 and ML 0 B and the wordline WL 0 , and includes two NMOS transistors T 42 and T 44 and two inverters INV 34 and INV 36 . When the stored mask data in the mask memory cell is “0”, cell node CN 34 of the mask memory cell has a logic low level and cell node CN 36 has a logic high level. When the mask data in this mask memory cell is “1”, the cell node CN 34 of the mask memory cell has a logic high level and the cell node CN 36 has a logic low level.
[0047] The TCAM cell TCC 00 according to this embodiment of the invention further includes two NMOS transistors T 34 and T 36 and two PMOS transistors T 38 and T 40 . The NMOS transistor T 34 has a first electrode (source or drain) coupled to a complementary compare line CL 0 B, a second electrode (drain or source) coupled to an internal node DX, and a control electrode coupled to a cell node CN 30 of the main memory cell. The NMOS transistor T 36 has a first electrode (source or drain) coupled to the compare line CL 0 , a second electrode (drain or source) coupled to the internal node DX, and a control electrode coupled to a cell node CN 32 of the main memory cell. The NMOS transistors T 34 and T 36 constitute a detection circuit for detecting whether comparand data transmitted to a compare line pair is matched with data stored in a main memory cell. The PMOS transistor T 38 has a first electrode (or source) coupled to a match line segment MATCH 00 , a second electrode (or drain) coupled to a match line segment MATCH 01 , and a control electrode coupled to the internal node DX. The PMOS transistor T 38 constitutes a match circuit for electrically connecting the match line segments MATCH 00 and MATCH 01 to each other when the comparand data is matched with stored data. The PMOS transistor T 40 has a first electrode (or source) coupled to the match line segment MATCH 00 , a second electrode (or drain) coupled to the match line segment MATCH 01 , and a control electrode coupled to a cell node CN 34 of the mask memory cell. The PMOS transistor T 40 constitutes a mask circuit for electrically connecting the match line segments MATCH 00 and MATCH 01 to each other in response to mask data stored in the mask memory cell.
[0048] According to such a circuit structure, when mask data is “0”, the match line segments MATCH 00 and MATCH 01 are electrically connected to each other through the PMOS transistor P 40 irrespective of compare result. Thus, the match line segment MATCH 01 is charged to a power supply voltage from the precharge circuit 180 P 0 ′ (see FIG. 7) through the match line segment MATCH 00 and the PMOS transistor T 40 . When the mask data is “1”, the electrical connection thereof is determined depending on the compare result. When the comparand data is matched with the data stored in the main memory cell, a logic level of the internal node DX becomes substantially a ground voltage, turning on transistor T 38 to electrically connect the match line segments MATCH 00 and MATCH 01 to each other. On the other hand, when the comparand data is not matched therewith, the internal node DX is coupled to a signal line CL 0 or CL 0 B (at a high level) turning off transistor T 38 to electrically separate the match line segments MATCH 00 and MATCH 01 from each other.
[0049] [0049]FIG. 9 is a circuit diagram showing another TCAM cell in the TCAM shown in FIG. 7. In FIG. 9 and FIG. 8, same numerals denote same components. The TCAM cell of FIG. 9 is substantially identical to the TCAM cell of FIG. 8, except that PMOS transistors T 46 and T 48 are added in FIG. 9. The PMOS transistor T 46 has a first electrode coupled to a complementary compare line CL 0 B, a second electrode coupled to an internal node DX, and a control electrode coupled to a cell node CN 32 of a main memory cell. The PMOS transistor T 48 has a first electrode coupled to a compare line CL 0 , a second electrode coupled to the internal node DX, and a control electrode coupled to a cell node CN 30 of the main memory cell. According to such a structure, a voltage of the internal node DX fully swings from a power supply voltage to a ground voltage. Otherwise, the TCAM cell of FIG. 9 may operate and obtain the same effect as the TCAM cell of FIG. 8.
[0050] As explained above, a ternary content addressable memory (TCAM) according to the embodiments of the present invention has a NAND-type match line structure, in which the level of a match line is changed, e.g., discharged/charged only when all data bits stored in TCAM cells of one word are matched with corresponding comparand data bits. This results in a reduction in power consumption and increased reliability and density. Transistors (e.g., T 14 and T 16 of FIG. 4) constituting a detection circuit are constructed to be complementary with a transistor (e.g., T 18 of FIG. 4) constituting a match circuit.
[0051] As a result, the TCAM cells according to embodiments of the invention are suitable for use in a high-density CAM and is stably operable at a low voltage.
[0052] While this invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. | A ternary content addressable memory (TCAM) having an array of cells arranged in rows and columns, each cell comprising of a main memory cell for storing a data bit and its complement and a pair of bit lines for carrying the data bit and its complement. A compare circuit having a pair of compare lines and an output node, the compare circuit coupled to the [data]main memory cell for comparing the data bit and its complement with corresponding compare lines and outputting a compared signal at the output node. A match circuit coupled to the output node of the compare circuit and a match input line and a match output line, the match circuit for selectively connecting the match input line to the match output line based on the compared signal. A mask memory cell for storing and outputting mask data and a mask circuit coupled to the match circuit and the match input line and the match output line for masking the compared signal or for selectively connecting the match input line to the match output line based on the mask data. | 6 |
FIELD OF THE INVENTION
[0001] The present invention relates to an illuminating system and more specifically to an energy saving illuminating system.
BACKGROUND OF THE INVENTION
[0002] Generally, illumination for homes, offices, stores etc, has been supplied by a relatively small object such as a light bulb used to illuminate a large area such as a room. Backsplashes, footboards, doorjambs and the like have been utilized in kitchens and bathrooms, in rooms of homes, offices and buildings. Generally ceramic tile, wood or similar material has been utilized. These have been used to serve as a seal between surfaces and a protective barrier against water splashes as in the case of backsplashes and against impact and abrasion, as in the case of footboards and door jambs. Short of the efforts to move away from traditional incandescent light bulbs, very little has been done to save energy in the way that we illuminate homes and offices.
[0003] What is needed is a material which would provide the uses mentioned above and would additionally provide illumination and do so in such a manner as to conserve the amount of energy traditionally used to illuminate a room and to accomplish this in an esthetically pleasing manner. Generally, illumination may be required for various needs and at various times. For illustration purposes, discussion is focused on a home. But similar principles apply to an office, store, warehouse etc. For example when someone is in a room, a different degree of illumination is required than when no one is in the room. A different degree of illumination is required in the evening than at night when every one is asleep. In addition the amount of illumination would vary depending on the purpose. For example a different degree of illumination is require for reading than to transverse from one room to the next.
[0004] Generally there is no need for illumination if no one is in a room. We usually leave lights on to aid in moving from room to room. By using motion sensors the energy saving illumination system would save energy by providing illumination when someone enters an area. For those instances when no one is in the room and illumination is required, this system provides a low energy ambient light. It is an excellent means of providing illumination when one traverses from one room to the next and for when everyone is asleep. In addition, lighting frequently tends to be very bright or non existent. The use of energy is greatest at the initial period when lights are first turned on. The energy saving illumination system would provide an alternative to the traditional incandescent bulb and reduce the many repeated times when an unnecessarily bright light is turned on for a brief period of time. By illuminating a doorjamb for example, the need to turn on a bright light just to locate the doorknob may be eliminated or reduced thereby saving energy. This is especially true if a renewable source of energy is utilized as an alternative means of energy to provide the illumination.
[0005] Developments have been made in illuminated materials The prior art related to the developments include the following:
[0006] Trudeau, Lauziere application Ser. No. 10/217,473 details an illuminating structure.
[0007] Mueller, Lys et, al, U.S. Pat. No. 7,358,929 describes a lighting system in which LED are imbedded within a tile, but there is no mention of enhancing the illumination or attempting to provide an energy savings.
[0008] While LED lights embedded in tiles are available, there has been little effort to provide an alternative to the light bulb as a means of illumination. Accordingly there remains a need for an energy saving illuminating system.
SUMMARY OF THE INVENTION
[0009] In view of forgoing disadvantages inherent in the prior arts, the general purpose of the present invention is to provide an illumination system designed to save energy, configured to include the advantages of the prior art, and to overcome the disadvantages of the prior art.
[0010] The present invention provides an energy saving illuminating system such that a source of illumination is enhanced and such that alternate sources of illumination may be reduced or eliminated and provide this preferably in an esthetically pleasing manner. The energy saving illuminating system provides a source of illumination, the power for which is preferably renewable, a means of enhancing the illumination, a means of conducting the illumination to a location where the illumination can be further enhanced. The illumination may additionally pass through a material which will continue to phosphoresce once the power and energy source are shut off.
[0011] Since the initial light source is being enhanced, conducted and phosphoresced, the power for which is provided preferably by a renewable means, the amount of energy required to create a similar amount of light without using the energy saving illumination system would be greater. Thus an energy savings would be created using this invention while an esthetically pleasant appearance is achieved.
[0012] The energy saving illumination system can serve as an ambient lighting thereby reducing the need to leave lights on during the night or to turn on brighter lights to illuminate the path.
[0013] This material can be utilized in floor and ceiling molding, kitchen and bathroom backsplashes, door jambs, fireplace surrounds, banisters, floors and ceilings, wall art as well as other uses.
[0014] These together with other aspects of the present invention, along with various features of novelty that characterize the invention, are pointed out with particularity in the claims annexed hereto and forming a part of the disclosure. For a better understanding of the invention, its operating advantages and its specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which therein are illustrated exemplary embodiments of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The advantages and features of the present invention will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings wherein like elements are identified with symbols, and in which:
[0016] FIG. 1 is a side exploded view of an energy saving illumination system according to an exemplary embodiment of the present invention.
[0017] FIG. 2 is a side view of an energy saving illumination system according to an exemplary embodiment of the present invention.
[0018] FIG. 3 is a front exploded view of an energy saving illumination system according to an exemplary embodiment of the present invention.
[0019] FIG. 4 is a side exploded view of an energy saving illumination system according to an exemplary embodiment of the present invention.
[0020] FIG. 5 is a front exploded view of an energy saving illumination system according to an exemplary embodiment of the present invention.
[0021] FIG. 6 is a front exploded view of an energy saving illumination system according to an exemplary embodiment of the present invention.
[0022] FIG. 7 is an exploded front perspective view of an energy saving illumination system according to an exemplary embodiment of the present invention.
[0023] Like reference numerals refer to like parts throughout the description of several views of the drawings.
DETAILED DESCRIPTION OF THE INVENTION
[0024] The detailed embodiments described herein detail for illustrative purposes are subject to many variation in structure and design. It should be emphasized however that the present invention is not limited to a particular energy saving illuminating system as shown and described. It is understood that various omissions, substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but is to cover the application or implementation without departing from the spirit or scope of the claims of the present invention.
[0025] The terms “first”, “second”, and the like, herein, do not denote any order, quantity, or importance, but rather, are used to distinguish one element from another, and the terms “a”, and “an”, herein do not denote a limitation of quantity, but rather denote the presence of at lease one of the referenced items.
[0026] In one aspect of the present invention, the energy saving illuminating system 100 contains a means of illumination. The illumination from a light source 101 or plurality of light sources is placed in a position or positions such that the emitted light can be enhanced by a means which preferably does not require the additional expenditure of costly energy. An example of, but not limited to, such a means of illumination may be a ribbon of LED lights 106 .
[0027] The energy required to illuminate the light source can be provided by a variety of means, preferably renewable, such as but not limited to energy from solar, wind, and/or etc. FIG. 1 illustrates a solar panel 108 connected to a rechargeable battery 109 which stores the power until needed, to illuminate a light source 101 . The rechargeable battery, solar panel, LED ribbon are readily available at various retailers and electronic supply stores. An energy source, preferable renewable, provided by means such as wind, solar and/or etc placed outdoors would need to have that energy routed to the illumination source which may be positioned in a different location such as indoors. Such means are readily available in the form of electrical wiring. Fuel cells such as direct methanol fuel cells DMFC can provide low amounts of power for long periods of time which is ideal for the energy saving illumination system. Although currently cost prohibitive, prices are expected to drop as technology improves and these may serve as another means of providing a useful power source which does not have to be outdoors as in the case of solar and wind.
[0028] An enhancement source to increase the illumination can be provided by various means such as, but not limited to reflection and, or magnification as well as other means. In FIG. 1 the light source 101 is positioned between a reflective material 102 and a structural material such as a backsplash, footboard, door jamb etc. Examples of a reflective material include but are not limited to a mirror, reflective foil, polished metal, etc. The reflective material 102 would be held in position to maximize the enhancement of the light source by a variety of means such as but not limited to glue, tape, screws and, or etc. One example of positioning the reflective material 102 is adhering it onto a decorative molding 103 , onto the backing 104 , and to the top of the structural material which for this example will be a tile 105 , by means such as, but not limited to, glue, tape, screws and or other such means.
[0029] For illustrative purposes, a translucent or transparent structural material such as a tile 105 for a kitchen backsplash will illustrate that although light will pass out through the face or front of the tile, some will pass up through the tile and be reflected off of the reflective material at the top of the tile. In addition some of the illumination will be reflected off of the reflective material 102 at the bottom, and off of the reflective material on the backing 104 , thus enhancing the original degree of illumination. A decorative molding similar to the one at the bottom can also be utilized to position the reflective material to the top of the tile (not shown). The reflective material at the top of the tile, would reflect the illumination in a downward direction and also against the reflective material 102 on the backing 104 . The reflective materials would be positioned such that the reflection of the light source would be maximized. Reflection from outside sources such as light coming through windows as well as others sources, would also be reflected and incorporated into the illumination being generated by the energy saving illuminating system. The illumination from a light source 101 acting on the reflective material 102 of the molding 103 , the backing 104 and the top of the tile 105 would cause some of the light rays to also be reflected onto the reflective material on the backing 104 thus enhancing the illumination. In FIG. 2 the light paths shown by arrows A, B, C are just some of the multitude of paths that the light could take. The light would pass through a surface. We are all familiar with the reflection of light off of mirrored surfaces, so there is no need for further examples.
[0030] Another means of increasing illumination would be by magnification. FIG. 3 illustrates an example where the illumination is provided by means of LED lights 107 in a LED ribbon 106 . The enhancement of the illumination is provided by means of a magnifying rod 301 . The magnified light is directed upward through the tile. Reflective material 102 on top of the tile 105 , reflects the illumination back through the tile again. Reflective material on the backing (not shown would also reflect the illumination back through the tile. Once again the tile in these examples are composed of transparent or translucent material such as glass, resin, plastic etc.
[0031] FIG. 4 illustrates an example of magnification in front of the light source 101 , the illumination from which is enhanced by a magnifier 402 positioned in front of the light source 101 . Reflective material 102 which adheres to the backing 104 and the top and bottom of the tile 105 further enhances the illumination as it passes through the tile.
[0032] While the example of the enhancement sources cited direct the illumination back through the surface, other possibilities are anticipated, such as directing some and/or all of the illumination out into the room. Another choice would be to direct some and/or all of the illumination up toward the ceiling as another means of illuminating the area.
[0033] Running through the tile 501 are a means of conducting the light from the source or sources through out the tile to the illumination enhancing material at another location. These conducting sources 402 are particularly beneficial in that there may be decorative objects 403 within the tile which would obstruct the light path from reaching the other illumination enhancing sources. Means of conduction may be, but not limited to, fiber optic strands, mirrors, glass and/or etc. In an example, fiber optic strands are designed to generally illuminate the light either at the ends or at the sides of the fiber optic strand. A means of focusing the light onto the end of the fiber optic strands may be needed to reduce light loss. In the example of the LED ribbon, each of the fiber optic cables would be positioned over a LED as illustrated in FIG. 5 . One such means of focusing the light is with the use of illuminators (not shown) which are available at most suppliers of fiber optic cables. FIG. 5 illustrates one example of the conducting strands 502 running in a parallel fashion. These conducting strands reduce the degree of loss and direct the illumination to the illumination enhancing material 102 . The conductive strands further aid in conducting illumination when the composition of the tile is such that it would block the illumination. These conducting sources 402 would preferable be positioned such that the illumination is visible at the face of the tile so that it is beneficial in illuminating the room. Some means of accomplishing this are positioning the strands within the tile but close enough to the face of the tile that the illumination is visible. Another means would be to adhere the conducting strands to the outside face of the tile. The conducting strands may be arranged to create a pleasant decorative appearance.
[0034] FIG. 6 illustrates another example of a means of distributing illumination form the LED source 107 when utilizing a non light conducting surface material such as ceramic tile 105 . By positioning the conducting strands 502 between the juncture of the tiles 105 and against a reflective surface 102 the illumination is further enhanced. When the light is emitted out the sides of the conducting strands the binding agent (not shown) joining the tiles would preferably permit the illumination into the room. For conducting strands where the light is emitted out the ends that would not be important since the illumination would occur along the area of the reflective material. It should be noted that when the surface is composed of material which precludes the passage of light, the enhancing material would be positioned in a manner and direction to compensate for that characteristic. In the previous examples the reflective material on the top and backing could not be directly against the surface. It could be positioned away from the surface. By using an angle or curve, the reflection of the illumination can still be utilized. It should be noted that in this and the previous examples that the number of strands per light source may vary, and that the number, thickness, and shape are for illustrative purposes only.
[0035] There exists in current development of organic light emitting diodes, OLED, a flexible newspaper like printing process, an inexpensive efficient light source. A thin layer of an organic compound that glows when an electrical charge is applied, the OLED may serve as an alternate light source when the process is readily and economically available. Combined with the renewable energy source and the phosphorescent aspect which will be discussed, this may serve as a means of applying the energy saving illumination system to surface materials such as the mentioned tile which are composed of materials which are not transparent or translucent. The enhancement of the illumination with the reflection or magnification previously discussed would be applicable with these OLED as the manufacturing costs decrease.
[0036] When a decorative object 703 is included within the surface material, the conductive strands 502 may be distributed between the objects as illustrated in FIG. 7 . These decorative objects may include interesting shapes such as hearts or flowers, or photographs and or etc. Since they may block some of the reflection from the backing, the conductive strands play a role in the overall illumination for the room. In surfaces which do not transfer light, the conductive strands provide a means of directing the illumination to the enhancement source as in the examples previously mentioned. They would direct the illumination to the reflective material at the back and top of the tile. These conductive strands 502 may be oriented in such a manner as to create an interesting or artistic pattern within the tile 701 so that they may appear as part of the decoration of the tile.
[0037] Channels (not shown) within the surface to allow the illumination to pass to the reflective material is another means of conducting the light in opaque material.
[0038] As an additional means of creating an appealing ambience, when illumination of different colors is utilized the conductive strand will emit a colored glow. A LED with red green, blue, light in a lamp which can vary the amount of illumination separately being emitted from each color can create a multitude of color variations. This will provide a multitude of illuminated colors to the tile and the room. An illuminator port may be needed to fully utilize the light carrying ability of the conductive strands.
[0039] The energy saving illumination system can provide an additional source of illumination, by utilizing a means of providing illumination even after the original source of illumination is turned off. One such means is to utilize a phosphorescent material which when excited by the light source, would continue to emit light after the light source is turned off. Currently phosphorescent powders and paint with non radioactive strontium can produce a phosphorescence glow time of over 8 hours. Because the surface area in the energy saving illumination system is greater than a light bulb, with the phosphorescent materials currently on the market, the glow produced should be sufficient to serve as a means of illuminating a hallway, a doorway, or serve as a night light. This should be more than sufficient to provide illumination during late night hours. when power would ordinarily be turned off. One means of incorporating such material is to utilize it within the composition of the face of the surface. One means is to combine a phosphorescent material to a the structural material such as ceramic clay, resin, plastic, glass etc. Another means is to utilize the phosphorescent material with the binding material. The binding material may incorporate the phosphorescent material preferably in suspension or solution with a hardening agent such as but not limited to resin, plastic, glass and etc. The binding material would incorporate the decorative objects creating a surface such as a mosaic tile. Another means is for the decorative objects to contain the phosphorescent material such that the shape of these decorative objects which create a pleasant glow when the power to the illuminating light source is turned off. Another means is to utilize a phosphorescent paint in a manner and location such that illumination will continue after the power is switched off. Various colors of phosphorescence are currently available on the market.
[0040] While a tile is utilized in the discussion, it should be noted that it is exemplary only and many variations are anticipated, for example a shape can be created so that these properties can be utilized to work in conjunction with existing surfaces. The item, such as a half moon molding, can be positioned on top of the existing backsplash in a kitchen or bath. and provide illumination and an appealing look to the existing backsplash. While the discussion described surfaces which where either transparent and translucent or surfaces which did not conduct light. Material exist which appear opaque but once illumination is applied they appear translucent and conducts illumination and color. This is a particularly beneficial when used with the conductive strands which would also provide a pleasant colored glow through the surface.
[0041] Replacing the light source if it should fail can be achieved by utilizing a means such as, but not limited to, clips, peel and stick tape, tacky glue, and, or etc to adhere it to the surface or the object that the surface is attached to, as for example a tile to a wall.
[0042] In a further effort to save energy, the surface material could be made out of recycled material such as recycled glass. The power would be attached to a motion sensor so the system would be illuminated only when some one enters the room.
[0043] In some instances a means of attaching the system to as wall or other surface may be required. For the example of a tile, some means of attaching the tile to the wall would include a peel and stick tape for do-it-yourselfers, grout, glue, clips, screws are just some of the means.
[0044] The energy saving system may be utilized in kitchens or bathrooms for counter tops, backsplashes and shower stalls In addition it may be utilized as floor boards, crown molding at ceilings or for door jambs. Floors and ceilings may also take advantage of such a system. These are just some of the potential uses for the energy saving illuminated system. | Disclosed is an energy saving illumination system. The energy saving illumination system comprising an energy source, preferably renewable, a means of illumination, a non energy requiring means of enhancing said illumination, a means of conducting said illumination, and an additional means of illumination not requiring additional commercial energy thereby creating an illumination system while providing energy savings over traditional means. | 4 |
This application is a divisional application of application Ser. No. 176,120 filed Mar. 31, 1988, now U.S. Pat. No. 4,847,665, in the name of Ranjit Singh Mand and entitled "Monolithic Integration of Electronic and Optoelectronic Devices". The specification and drawings of application Ser. No. 176,120 are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
The present relates generally to monolithic integration of optoelectronic and electronic devices. More particularly, the invention relates to monolithic integration of DOES and HFET devices.
A number of recent publications disclose the desirability of integrating both optoelectronic devices and electronic devices on a single monolithic substrate. See for example Wada et al, IEEE Journal of Quantum Electronics, Vol. QE-22, No. 6, June 1986, pp 805-821; Nakamura et al, IEEE Journal of Quantum Electronics, Vol. QE-22, No. 6, June 1986, pp 822-826; Maeda et al, Hitachi Review, Vol. 35, No. 4, 1986, pp 213-218; and Shibata et al, Appl. Phys. Lett. 45(3), Aug. 1, 1984, pp 191-193. These advantages include higher speed operation and better noise performance due to reduction of parasitic reactances, and higher system reliability and simpler system assembly due to reduction of system parts counts.
Unfortunately, the semiconductor layers required for the construction of most optoelectronic devices differ from the semiconductor layers required for the construction of most electronic devices. As a result, optoelectronic devices have been integrated onto the same substrate as electronic devices by growing the semiconductor layers required for optoelectronic devices onto a semiconductor substrate, etching the grown layers to expose the semiconductor substrate at locations where electronic devices are desired while masking the grown layers at locations where optoelectronic devices are desired, and forming electronic devices in the substrate and optoelectronic devices in the grow layers.
This procedure is rather complicated and has significant disadvantages. In particular, the grown layers protrude beyond the surface of the exposed substrate so that masks used to define the electronic devices are held away from the substrate surface during photolithography. This limits the resolution of the photolithography process and correspondingly limits the density of the electronic devices. Moreover, the electronic devices are formed at an etched surface of the substrate. The etching process degrades the quality of this surface and this affects the functioning of the resulting electronic devices. In particular, field effect transistors (FETs) formed at such an etched surface typically have nonuniform threshold voltages. Both of the above effects limit the yield of such integration processes.
In another known method for integrating optoelectronic devices onto the same substrate as electronic devices, a groove is formed in the substrate and the semiconductor layers required for optoelectronic devices are grown only in the groove. Optoelectronic devices are then formed in the groove, while electronic devices are formed on the substrate alongside the groove. Unfortunately, the groove required for this process must be made 5 microns to 10 microns deep in order to accommodate all of the semiconductor layers required for optoelectronic devices, and a step discontinuity of this magnitude impairs the resolution of photolithographic processes used to define the optoelectronic and electronic devices.
Recent publications have disclosed a family of electronic and optoelectronic devices including the Bipolar Inversion Channel Field Effect Transistor (BICFET), Heterojunction Field Effect Transistor (HFET), Heterostructure Junction Field Effect Transistor (HJFET), HFET PhotoDetector (HFETPD) and Double heterostructure OptoElectronic Switch (DOES). See for example Taylor et al, IEEE Trans. Electron Dev., Vol. ED-32, No. 11, November 1985, pp 2345-2367; Taylor et al, Electron. Lett., Vol. 22, No. 15, July 1986, pp 784-786; Taylor et al, Electron. Lett., Vol. 23, No. 2, January 1987, pp 77-79; Simmons et al, Electron. Lett., Vol. 22, No. 22, October 1986, pp 1167-1169; Simmons et al, Electron. Lett., Vol. 23, No. 8, April 1987, pp 380-382; Taylor et al, Appl. Phys. Lett. 50(24), June 1987, pp 1754-1756; Taylor et al, J. Appl. Phys. 59(2), January 1986, pp 596-600; Taylor et al, Appl. Phys. Lett. 48(20), May 1986, pp 1368-1370; Taylor et al, Appl. Phys. Lett. 49(21), November 1986, pp 1406-1408; and Simmons et al, IEEE Trans. Electron. Dev., Vol. ED-34, No. 5, May 1987, pp 973-984.
SUMMARY
The present invention seeks to provide a method for monolithically integrating DOES devices and HFET devices which overcomes some or all of the problems encountered in known methods for monolithically integrating optoelectronic devices with electronic devices. The term "HFET devices" as used in this specification is meant to encompass HFET transistors, HFET photodetectors (HFETPDs) and other similar devices.
According to one aspect of the present invention there is provided a method for making a monolithic integrated circuit comprising DOES devices and HFET devices, the method comprising:
forming a semi-insulating substrate having regions of wide band gap semiconductor of a first conductivity type recessed therein at predetermined locations, the regions being exposed at a surface of the substrate;
forming a layer of narrow band gap semiconductor having a second conductivity type opposite to the first conductivity type over the surface of the substrate;
forming a sheet charge of the first conductivity type over the layer of narrow band gap semiconductor;
forming a layer of wide band gap semiconductor of the second conductivity type over the sheet charge; and
forming ohmic contacts to the layer of wide band gap semiconductor of the second conductivity type and to the layer of wide band gap semiconductor of the first conductivity type to define DOES devices at the predetermined locations, and forming HFET devices at other predetermined locations.
According to another aspect of the invention there is provided a monolithic integrated circuit comprising:
a semi-insulating substrate having regions of wide band gap semiconductor of a first conductivity type recessed therein at specific locations;
a layer of narrow band gap semiconductor on the substrate, the narrow band gap semiconductor having a second conductivity type opposite to the first conductivity type and contacting the regions of wide band gap semiconductor;
a sheet charge of the first conductivity type on the layer of narrow band gap semiconductor;
a layer of wide band gap semiconductor of the second conductivity type on the sheet charge; and
ohmic contacts to the layer of wide band gap semiconductor of the second conductivity type and to the layer of wide band gap semiconductor of the first conductivity type defining DOES devices at the specific locations, and HFET devices formed in the semiconductor layers at other specific locations.
The wide band gap semiconductor of the first conductivity type is provided only at those predetermined locations where DOES devices are desired. This material is provided for carrier confinement in the overlying narrow band gap semiconductor of the second conductivity type as is required for efficient light generation in the DOES devices. This material is not provided at other predetermined locations where HFET devices are desired as it would constitute a shunt path which would degrade the high frequency operation of the HFET devices.
Because most of the semiconductor layers are common to the optoelectronic and electronic devices, there is little or no step discontinuity between the optoelectronic and electronic devices. Thus, standard photolithographic procedures may be used with little or none of the impairment encountered in the previously known methods of integration described above. Moreover, the HFET devices are formed at a grown or deposited surface of the substrate rather than at an etched surface. As a result, the HFET devices have relatively uniform threshold voltages.
Preferably, ohmic contacts are formed to the wide band gap semiconductor of the second conductivity type by forming a layer of heavily doped wide band gap semiconductor of the second conductivity type on the wide band gap semiconductor of the second conductivity type at the predetermined locations, forming a layer of heavily doped narrow band gap semiconductor of the second conductivity type on the heavily doped wide band gap semiconductor of the second conductivity type, and forming a metallic layer on the heavily doped narrow band gap semiconductor. The heavily doped wide band gap semiconductor of the second conductivity type, heavily doped narrow band gap semiconductor of the second conductivity type, and the metal together constitute the ohmic contact to the wide band gap semiconductor of the second conductivity type.
Where the semi-insulating substrate is of narrow band gap material, regions of narrow band gap semiconductor of the first conductivity type are provided beneath the regions of wide band gap semiconductor of the first conductivity type. The narrow band gap semiconductor of the first conductivity type acts as a buffer layer to ensure high quality crystal structure in the overlying wide band gap semiconductor of the first conductivity type. Moreover, the narrow band gap semiconductor of the first conductivity type may be heavily doped, and portions of this material may be exposed and coated with a metallic layer to form an ohmic contact to the wide band gap semiconductor of the first conductivity type, the metallic layer and the heavily doped narrow band gap semiconductor of the first conductivity type constituting the ohmic contact.
Recesses may be etched into the substrate at the predetermined locations and the layers of narrow band gap semiconductor and wide band gap semiconductor of the first conductivity type may be formed so as to substantially fill the recesses. These recesses may be an order of magnitude shallower than the grooves used in previously known integration methods described above since they need only accommodate one or two of the semiconductor layers required for optoelectronic devices. The grooves used in the previously known integration methods must accommodate all of the semiconductor layers required for optoelectronic devices and therefore must be deeper.
Alternatively, layers of narrow band gap semiconductor and wide band gap semiconductor of the first conductivity type may be formed over the entire substrate and oxygen may be implanted at the other predetermined locations to render the narrow band gap semiconductor and wide band gap semiconductor at said other predetermined locations semi-insulating. Both of these approaches eliminate or reduce protrusion of the DOES devices beyond the HFET devices due to additional carrier confinement layers in the DOES devices.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which:
FIGS. 1 to 6 are cross-sectional views of a monolithic integrated circuit according to a first embodiment at successive stages in its manufacture;
FIG. 7 is a top elevational view of the integrated circuit of FIGS. 1 to 6;
FIG. 8 is a top elevational view of a monolithic integrated circuit according to a second embodiment;
FIG. 9 is cross-sectional view of the integrated circuit of FIG. 9 taken on section line 9--9 of FIG. 8;
FIG. 10 is a cross-sectional view of a monolithic integrated circuit according to a third embodiment;
FIG. 11 is a plan view of the monolithic integrated circuit of FIG. 10;
FIGS. 12 to 14 are cross-sectional views of a monolithic integrated circuit according to a fourth embodiment at successive stages in its manufacture; and
FIG. 15 is a cross-sectional view of a monolithic integrated circuit according to a fifth embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the description which follows, "N" and "P" designate doping to a level between 10 16 and 10 18 carriers per cubic centimeter, "N-" and "P-" designate doping to a level between 10 15 and 10 16 carriers per cubic centimeter, and "N+" and "P+" designate doping to a level between 10 18 and 10 19 carriers per cubic centimeter.
In a first embodiment, a monolithic integrated circuit comprising DOES and HFET devices is manufactured according to a series of process steps shown in FIGS. 1 to 6.
As shown in FIG. 1, a substantially planar semi-insulating GaAs substrate 10 is masked with photoresist and etched to define recesses 12 approximately 5000 angstroms deep at predetermined locations where DOES devices are desired.
As shown in FIG. 2, a layer 14 of silicon nitride is deposited on the substrate 10, masked with photoresist and etched to remove the silicon nitride only from the recesses 12.
As shown in FIG. 3, a layer of narrow band gap semiconductor of a first conductivity type in the form of a N+ GaAs layer 16 approximately 2000 angstroms thick and doped with approximately 5×10 18 silicon atoms per cubic centimeter is deposited by molecular beam epitaxy (MBE) over the silicon nitride layer 14 and recess 12. The N+ GaAs layer 16 is polycrystalline where it is grown on the silicon nitride. layer 14 and monocrystalline in the recess 12 where it is grown directly on the semi-insulating GaAs substrate 10. As further shown in FIG. 3, a layer of wide band gap semiconductor of the first conductivity type in the form of a N+ GaAlAs layer 18 approximately 3000 angstroms thick and doped with approximately 5×10 18 silicon atoms per cubic centimeter is deposited by MBE over the layer 16 of N+ GaAs. The composition of the GaAlAs layer 18 is ramped from Ga 1 .0 Al 0 .0 As to Ga 0 .7 Al 0 .3 As over the first approximately 100 angstroms of the layer. Like the N+ GaAs layer 16, the N+ GaAlAs layer 18 is monocrystalline in the recess 12 and polycrystalline elsewhere according to the crystallinity of the underlying material.
As shown in FIG. 4, the layers 14, 16 and 18 are preferentially etched to preferentially remove polycrystalline material, leaving only the monocrystalline N+ GaAs and N+ GaAlAs layers 16, 18 in the recess 12. The remaining N+ GaAs and GaAlAs layers 16, 18 substantially fill the recess 12.
As shown in FIG. 5, a further series of monocrystalline layers 20, 22, 24, 26, 28 are deposited over the N+ GaAs and GaAlAs layers 16, 18 and over exposed portions of the substrate 10 by MBE. A layer of narrow band gap semiconductor of a second conductivity type in the form of a layer 20 of P- GaAs approximately 1 micron thick and doped with approximately 5×10 5 beryllium atoms per cubic centimeter is deposited directly on the N+ GaAlAs layer 18 and substrate 10. A sheet charge in the form of a layer 22 of N+ Ga 0 .7 Al 0 .3 As approximately 40 angstroms thick and doped with approximately 10 19 silicon atoms per cubic centimeter is deposited on the P- GaAs layer 20.
A layer of wide band gap semiconductor of the second conductivity type in the form of a layer 24 of P Ga 0 .7 Al 0 .3 As approximately 350 angstroms thick and doped with approximately 10 17 beryllium atoms per cubic centimeter is deposited on the sheet charge layer 22.
Two further layers 26, 28 used in formation of ohmic contacts to the P GaAlAs layer 24 are formed over the P GaAlAs layer 24. These layers include a layer of heavily doped wide band gap semiconductor of the second conductivity type in the form of a P+ Ga 0 .7 Al 0 .3 As layer 26 approximately 500 angstroms thick and doped with approximately 10 19 beryllium atoms per cubic centimeter deposited by MBE directly on the P GaAlAs layer 24, and a layer of heavily doped narrow band gap semiconductor of the second conductivity type in the form of a P+ GaAs layer 28 approximately 500 angstroms thick and doped with approximately 10 19 beryllium atoms per cubic centimeter deposited by MBE o the P+ GaAlAs layer 26.
DOES devices are defined at those predetermined locations where recesses 12 were formed and substantially filled with N+ GaAs and GaAlAs layers 16, 18. Such a DOES device 30 is shown in FIG. 6. The DOES device 30 is defined by forming ohmic contacts to the layer 24 of P GaAlAs and to the layer 18 of N+ GaAlAs. The ohmic contact to the layer 24 of P GaAlAs defines an emitter electrode of the DOES device and is completed depositing a metallic layer 32 on the P+ GaAs layer 28 over the recesses 12, the metallic layer 32 and the P+ semiconductor layers 26, 28 constituting the ohmic contact. An opening 34 is formed in the metallic layer 32 for transmission of light to and from the DOES device. The ohmic contact to the layer 18 of N+ GaAlAs defines a collector electrode of the DOES device and is formed by masking with photoresist and etching to form recesses 36 extending through the P+ GaAs layer 28, P+ GaAlAs layer 26, P GaAlAs layer 24, N+ GaAlAs sheet charge layer 22, P- GaAlAs layer 20 and N+ GaAlAs layer 18 to expose portions of the N+ GaAs layer 16, and forming a metallic layer 38 in the recesses 36. The metallic layer 38 and N+ GaAs layer 16 together constitute the ohmic contact to the N+ GaAlAs layer 18.
HFET devices in the form of HFET transistors are formed at other predetermined locations in the semiconductor layers 20, 22, 24, 26 and 28. Such a HFET transistor 40 is shown in FIG. 6. The HFET transistor 40 is formed by depositing a metallic gate electrode 42, implanting silicon into the semiconductor layers 20, 22, 24, 26 and 28 and rapid thermal annealing to activate the silicon, thereby defining self-aligned N+ source and drain regions 44, 45, and depositing metallic source and drain electrodes 47,48 over the source and drain regions respectively.
HFET devices in the form of HFETPDs are formed at still other predetermined locations in the semiconductor layers 20, 22, 24, 26 and 28. Such a HFETPD 50 is shown in FIG. 6. The HFETPD 50 is formed by depositing a metallic gate electrode 52, implanting silicon into the semiconductor layers 20, 22, 24, 26 and 28 and rapid thermal annealing to activate the silicon, thereby defining a self-aligned N+ anode region 54, and depositing a metallic anode 55 over the anode region 54. An opening 53 is formed in the gate electrode 52 for transmission of light to the HFETPD. The HFETPD is completed by masking with photoresist and etching to define a recess 57 extending through the P+ GaAs layer 28, P+ GaAlAs layer 26, P GaAlAs layer 24 and N+ GaAlAs sheet charge layer 22 to expose portions of the P- GaAs layer 20, and forming a metallic cathode 58 in the recess 57.
To minimize the required number of process steps, the DOES and HFET devices are formed together rather than in succession. In particular, all of the gate metal layers 32, 42 and 52 are formed in a single metallization step, followed by implantation of all of the self-aligned source, drain and anode regions in a single implantation step. All of the collector, source, drain and anode contacts 38, 47, 48 and 55 are then made in a second single metallization step, and the cathode contact is made in a separate metallization step.
A layer 60 of silicon nitride is formed by chemical vapour deposition (CVD) over the DOES and HFET devices, and openings 62 are etched through this layer over the contacts 32, 38, 42, 47, 48, 52, 55, 58. A metallic layer 64 is formed over the silicon nitride and contacts using known lift off techniques to define contact pads 66 for the DOES and HFET devices.
Where isolation between adjacent HFET devices is required, known isolation techniques employing mesa etching or boron implantation may be used.
The DOES and HFET devices described above operate essentially as described in Taylor et al, J. Appl. Phys. 59(2), January 1986, pp 596-600, Taylor et al, Electronics Letters, Vol. 22, No. 15, July 1986, pp 784-786 and Taylor et al , Appl. Phys. Lett. 50(24), June 1987, pp 1754-1756.
A plan view of the resulting devices is shown in FIG. 7.
A monolithic integrated circuit according to a second embodiment is shown in FIGS. 8 and 9. This integrated circuit comprises a DOES device 30 and a HFETPD device 50 fabricated as described above. The DOES device 30 and the HFETPD device 50 are optically interconnected by means of a polymer layer 70 formed at an upper surface of the integrated circuit so as to form an optical waveguide. The polymer layer 70 is formed with tapered end portions 72 provided with a mirror finish over the openings 34, 53 in the DOES emitter electrode 32 and the HFETPD gate electrode 52 so as to couple light emerging from the emitter opening 34 of the DOES device 30 along the polymer layer 70 and through the gate opening 53 of the HFETPD device 50.
The DOES device 30 of the embodiments described above operates as a light emitting diode (LED). A third embodiment shown in FIGS. 10 and 11 comprises a monolithic integrated circuit having a DOES device 300 capable of operation as a laser. This monolithic integrated circuit is fabricated as described above for the first embodiment, except that the N+ GaAlAs layer 18 is made 1 micron thick (instead of 3000 angstroms as in the first embodiment), the P- GaAlAs layer 20 is made 1000 angstroms thick (instead of 1 micron as in the first embodiment) and the P+ GaAlAs layer 26 is made 1 micron thick (instead of 500 angstroms thick as in the first embodiment). With these thickness modifications, and with formation of suitably cleaved or dry etched end facets 302, 304 the layers 18, 20 and 26 and the end facets 302, 304 define an optical cavity capable of supporting edge emitting laser action. The thickness of the other layers and the doping of all of the layers is as described above for the first embodiment.
HFET devices in the form of an HFET transistor 400 and an HFET photodetector 500 can also be formed in the semiconductor layers having thicknesses modified according to the third embodiment. However, because the P- GaAlAs layer 20 is very thin and the overlying P+ GaAlAs layer 26 is relatively thick in the structure according to the third embodiment, the HFET photodetector 500 will be very inefficient when illuminated through a gate opening in a direction normal to the substrate as in the first embodiment. Accordingly, in the third embodiment, the HFET photodetector is illuminated through a cleaved or dry etched edge facet 502 in a direction extending parallel to the gate, and no opening is provided in the gate contact 52. A suitable anti-reflection coating may be applied to the cleaved or dry etched facet 502.
In a fourth embodiment shown in FIGS. 12 to 14, a layer 16 of N+ GaAs is formed over the entire semi-insulating substrate 10, a layer 18 of N+ GaAlAs is formed over the entire N+ GaAs layer 16, and a layer 19 of silicon nitride is grown on the N+ GaAlAs layer 18. A layer 21 of photoresist is deposited on the silicon nitride layer 19 and developed to mask only predetermined locations where DOES devices are desired. Exposed portions of the silicon nitride layer 19 are then etched away so that the silicon nitride layer 19 remains only at the predetermined locations where DOES devices are desired. Oxygen is then implanted into the N+ GaAlAs and GaAs layers 16, 18 where they are not protected by the silicon nitride 19 and photoresist 21. The implanted oxygen renders the semiconducting layers 16, 18 semi-insulating except at the predetermined locations where the semiconducting layers 16, 18 are protected by the silicon nitride 19 and photoresist 21 as shown in FIG. 12.
The remaining photoresist 21 and silicon nitride 19 are then etched away to expose the semiconducting layers 16, 18, and semiconducting layers 20, 22, 24, 26 and 28 are grown as described in the first embodiment and as shown in FIG. 13. DOES devices, HFET transistor devices 40 and HFETPD devices 50 are then formed in the semiconducting layers 20, 22, 24, 26, 28 as described in the first embodiment and as shown in FIG. 14.
Numerous modifications of the embodiments described above are within the scope of the invention. For example, semiconductors other than GaAs and GaAlAs could be used. InP, InGaAs, InAlAs and other III-V semiconductors would also be appropriate for these devices.
For example, an analogous integrated circuit shown in FIG. 15 could be fabricated by substituting a semi-insulating InP substrate 110 for the GaAs substrate 10, an N+ InP layer 117 for the N+ GaAs and GaAlAs layers 16,18, a P-InGaAsP layer 120 for the P- GaAs layer 20, a N+ InP layer 122 for the sheet charge 22, a P InP layer 124 for the P GaAlAs layer 24, a P+ InP layer 126 for the P+ GaAlAs layer 26, and a P+ InGaAs layer 128 for the P+ GaAs layer 28. In such an integrated circuit, light could be coupled into and out of the optoelectronic devices through the In substrate.
The devices described above rely on an N-type channel. Complementary devices relying on P-type channels could be formed by replacing the N-type layers with P-type layers and vice versa. The N-type channel devices are preferred due to the higher mobility of majority carriers in these devices.
Dopants other than silicon and beryllium may be used to provide the required conductivity type of the various layers.
The devices may be optically interconnected by means other than those described above. For example, Goodman et al, Proceedings of the IEEE, Vol. 72, No. 7, July 1984, pp 850-866 describes alternative optical interconnection methods. | In the monolithic integration of HFET and DOES device, a wide band gap carrier confining semiconductor layer is provided only at predetermined locations where DOES devices are desired. This layer is not provided at other predetermined locations where HFET devices are desired as it would constitute a shunt path which would degrade the high frequency operation of the HFET devices. The invention is particularly useful where monolithic integration of optical sources, optical detectors, and electronic amplifying or switching elements is desired. | 8 |
BACKGROUND OF THE INVENTION
This invention is concerned with an improved method and apparatus for stripping a fibrous web from a rotating cylinder in a textile machine, particularly but not exclusively from a doffer in a carding machine.
It is an object of the invention to eliminate the drawback inherent in the use of vibrating stripping combs which are sometimes employed to strip a fibrous web from a rotative cylinder in a textile machine. Such combs for mechanical reasons have a speed limit of 3000 picks per minute and therefore cannot strip the doffer of carding machines of modern design the output of which is more than 90 meters per minute and in some instances exceeds 140 - 150 meters per minute. The use of stripping rollers provided with card clothing is known, but such rollers are not of universal application and require a deionization device for the air which becomes electrostatically charged, particularly when synthetic fibers are to be processed.
SUMMARY OF THE INVENTION
According to the present invention there is provided a method for stripping a web issuing from a carding machine comprising the steps of facilitating the stripping of the web from a rotating stripping roller by employing pressurized air impulses issuing through apertures in the stripping roller covering, the apertures being distributed over the major surface of the covering, arranging for the air impulses to be periodic and to issue as the apertures register on rotation of the stripping roller with an air chamber within the said roller, and arranging the location of which so that such registration occurs relative to a plane through the axes of rotation of the upper dragging roller and the stripping roller.
According to the present invention there is also provided an apparatus for stripping a web issuing from a carding machine comprising a hollow stripping roller arranged for rotation and having a plurality of apertures over its carding surface, stationary means within the stripping roller defining with the adjacent surface of the stripping roller an air chamber, a pressurized air source to feed the said air chamber, the said apertures during rotation of the stripping roller registering successively with the said air chamber and creating air impulses to facilitate stripping of the web, the air chamber being arranged to direct the impulses relative to a predetermined plane with regard to web dragging rollers.
Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings;
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a somewhat schematic vertical sectional elevational view perpendicular to the axes of a doffer and associated stripping roller and to the axes of two rollers dragging the web to the calenders or to a web drawing apparatus such as that known sold under the T. M. CARDPEN.
FIG. 2 is a front elevational view of the central portion only of a stripping roller such as shown in FIG. 1 but modified for large front carding machines;
FIG. 3 is a partial perspective view of a modified stripping roller;
FIG. 4 is a developed plan view of the stripping roller of FIG. 3 or a modification thereof;
FIGS. 5 and 6 are fragmentary perspective views showing respectively the two opposite sides of a stripping roller support structure;
FIGS. 7 and 7a show a carding cloth covering portion for the stripping roller respectively in sectional and side view.
FIGS. 8 and 9 show two elevational side views of FIG. 6 illustrating the operation of a device for adjusting the gap between the two web dragging rollers.
DETAILED DESCRIPTION OF EMBODIMENTS
In the example illustrated in FIG. 1 a doffer 1 is provided in known manner with a carding cloth consisting of a metal toothed band wound around the cylindrical surface of the doffer 1. The windings of the carding cloth are very close so as to give a serrated surface without significant discontinuities.
A stripping roller 2 according to this invention is provided with a card clothing (FIG. 7, 7a) consisting of an extruded metallic band 4 punched with isosceles triangle profiled teeth. The step of the windings is 12-15 times the thickness of the band and therefore relatively large (see FIGS. 2, 3). The foot 4a of the band 4 is housed in a groove milled in the outer surface of the stripping roller and the band is mounted under tension. As may be seen from FIG. 7a the punched band is housed so that only the teeth extend above the surface of the stripping roller.
The stripping roller 2 is hollow and houses a stationary hollow cylinder 5 adapted to be fed with pressurized air through an inlet union which is preferably co-axially disposed as in the example shown in FIG. 3. The stationary hollow cylinder 5 is preferably made of aluminum and extruded with a longitudinal depression or groove 7 in its surface so as to define with the internal surface 2a of the stripping roller 2 an air chamber 9 to be fed as stated, by the pressurized air through one or more apertures 10 bored in the bottom wall of the said groove 7 and communicating with the air inlet. The wall of the stripping roller 2 is formed with a number of apertures or holes 0, 0 1 -- see FIG. 4 -- arranged to be periodically fed with pressurized air only when the holes open to the pressurized air chamber 9 during the rotation of the stripping roller. A pair of web dragging rollers 20 and 30 are provided adjacent to the pressurized air chamber 9 and are arranged such that the plane containing the axis of the hollow stationary cylinder 5 and the axis of the web dragging roller 20 coincides with the medial longitudinal plane of pressurized air chamber 9 (see FIG. 1).
The stationary hollow cylinder 5, the stripping roller 2 and the two web dragging rollers 20 and 30 are mounted to rotate in two supporting members 36 and 40 secured to the carding machine frame. The two rollers 20 and 30 are driven oppositively, as shown, by a drive spindle 50 (FIG. 5). The latter carries a toothed pinion 60 and is fixed to the stripping roller 2 as well to a toothed wheel 70. The spindle of the upper roller 20 terminates with a toothed pinion 80. A link chain 90 engages the toothed wheels 70 and 80 whereby the upper roller 20 and the stripping roller 2 are rotated in the same direction (see FIG. 1). A pinion 15 is fixed to the other end of the upper roller 20 and meshes with a pinion 25 on the lower roller 30 so that the lower roller 30 is rotated oppositely to the upper roller 20.
Whereas the stationary hollow cylinder 5 illustrated in FIG. 1 is dimensioned to conform closely to the inner surface of the stripping roller 2, as shown by the FIG. 3 the internal stationary hollow cylinder 5 instead of having a groove profiled depression 7 may be provided with two projecting ribs 8 and 8a projecting from its surface. The apertures for the passage of the air may be milled from the portion of the cylinder located between the two said ribs whereby a greater clearance is provided between the stripping roller 2 and the surface of the internal stationary cylinders 5.
In order to adapt the stripping apparatus to the nature e.g. thickness or weight of any web, the device as shown in the FIGS. 8 and 9 permits adjustment of the gap (a-b) between the two dragging feeding rollers 20 and 30, whereby a correct gripping of the web may be secured. Thus in this preferred embodiment the spindles of rollers 20, 30 are mounted in bearings 91, 92, the outside bush 91a, 92a of each which is eccentric with respect to the axis of the web dragging rollers 20, 30 with both of said outside bushes being provided with a locking device consisting of a dowel 33, 34 respectively as shown.
Clearly if a 180° rotation of bushes is effected it is possible to pass from a minimum of gap (clearance) (b) (FIG. 9) for example of 0.2 millimeters (for a web of 3-10 grs/m 2 of cotton carding machines) to a maximum of clearance (a) of 2 millimeters (FIG. 8) for a web of 70 grs/m 2 of a wool carding machine.
Two cleaning blades 44-65 are arranged smoothly pressed respectively against the web dragging rollers 20-30.
The two web dragging rollers may be driven at a speed securing a slight web drawing.
The stationary roller 5 may be mounted so as to permit an angular adjustment thereof in order to find the optimum position of incidence for the pressurized air currents against the surface of the upper web dragging roller 20.
DESCRIPTION OF OPERATION
On each registration of the apertures 0 (0 1 ) on rotation of the stripping roller 2 with the pressurized air chamber 9, a number of pressurized air impulses are created. These impulses assist the stripping roller 2 to progressively detach the web (V) from the doffer. When no aperture registers with the pressurized air chamber 9 a pressure gradient develops in the air chamber 9.
With reference to the FIG. 4, (M) shows the developed surface of the stripping roller 2 and (V) the web. The web V continuously receives a series of impulses directed to zones distributed along successives generatrices I, . . . VI. Consequently the impulse locations are distributed over the whole web surface which ensures that an easy and full detachment of web V from the stripping roller 2 is effected. If the arrangement of the apertures is staggered as shown by the crossed circles 0 1 , the impulse frequence is doubled. Such detachment may be likened to the turning over of a book page.
The pressurized air currents, namely the air impulses through the apertures of the stripping roller 2 and the continuous small air currents leaking through the apertures not registering with the pressurized air chamber 9, create a deionisation environment which suppresses static electricity.
By providing the stripping roller with the card clothing having isosceles triangle profiled teeth, the card clothing may be applied to the stripping device which is to be rotated either clockwise or anti-clockwise. Such a stripping roller may therefore be incorporated in many different carding machines.
In FIG. 2 the stripping roller is provided with a zone R with closer holes for the purpose of longitudinally pneumatically dividing the web V into two sections as is often required in larger sized carding machines. This may eliminate the use of known web cutting devices. Such a zone R is advantageous for wool carding machines presenting a large front, double calendering devices and two individual cans.
A fan may be arranged within the hollow cylinder 5. The fan may be coupled electrically with an electric motor which may be mounted on a shoulder of the machine. Alternatively, the fan may be driven by the transmission gearing of the carding machine through a gear train.
The device described may incorporate modifications known in the art. In addition no specific limitation is imposed for the number and the disposition of the holes on the stripping roller. One of the web dragging rollers, by example web dragging roller 20, may have a helical groove which facilitates conveying the web from the web dragging rollers to the calendering apparatus (not shown).
From the FIGS. 2 and 3 is should be apparent that spiral winding of card clothing may be effected with one, two or three separate windings. The spiral step for two adjacent windings is 12-15 times the thickness of the card clothing steel band.
When stripping a web consisting of synthetic fibres with high electrostatic charge, it is appropriate to humidify the air passing into the opening 6 of the stationary cylinder 5.
When stripping a web consisting of cotton fiber, the air currents may only be necessary whilst initiating the stripping and thereafter the air impulses may be discontinued. | In apparatus for stripping a fibrous web from the doffer of a carding machine, provision is made for pneumatically assisting the dragging rollers to remove web from the stripping roller. This is achieved by directing air impulses towards a dragging roller from within the stripping roller. An air chamber within the stripping roller is arranged such that the impulses are directed in a predetermined direction, as apertures in the stripping roller register therewith. Carding cloth covering the stripping roller has appropriately, toothed, stepped windings. | 3 |
BACKGROUND OF THE INVENTION
This invention relates generally to apparatus and methods for sensing physical phenomena and particularly to fiber optic sensing systems. This invention relates particularly to fiber optic sensors that respond to changes in a selected field quantity such as pressure, magnetic field, electric field, etc. Still more particularly, this invention relates to fiber optic interferometric sensors that respond to underwater perturbations such as acoustic wavefronts by producing a phase difference in two light beams propagated by fiber optic material.
Optical fibers can be made sensitive to a large number of physical phenomena, such as acoustic waves and temperature fluctuations. An optical fiber exposed to such phenomena changes the amplitude, phase or polarization of light guided by the fiber. Optical fibers have been considered for use as sensing elements in devices such as microphones, hydrophones, magnetometers, accelerometers and electric current sensors.
A hydrophone array or acoustic sensor array may be formed as an integral, self-contained linear array of hydrophones on a single cable. Conventionally, such an array is made up of electromechanical transducer elements, principally piezoelectric devices, which generate electrical signals in response to pressure variations. These conventional sensors typically are active devices that require many electrical wires or cables. These sensors have the disadvantage of being susceptible to electrical noise and signal cross talk.
Fiber optic Mach-Zehnder and Michelson interferometers respond to the phenomenon being sensed by producing phase differences in interfering light waves guided by optical fibers. Detecting phase changes in the waves permits quantitative measurements to be made on the physical quantity being monitored.
A fiber optic Mach-Zehnder interferometer typically has a reference arm comprising a first length of optical fiber and a sensing arm comprising a second length of optical fiber. The sensing arm is exposed to the physical parameter to be measured, such as an acoustic wavefront, while the reference arm is isolated from changes in the parameter. When the Mach-Zehnder interferometer is used as an acoustic sensor, acoustic wavefronts change the optical length of the sensing arm as a function of the acoustic wave pressure amplitude. An optical coupler divides a light signal between the two arms. The signals are recombined after they have propagated through the reference and sensing arms, and the phase difference of the signals is monitored. Since the signals in the reference and sensing arms had a definite phase relation when they were introduced into the arms, changes in the phase difference are indicative of changes in the physical parameter to which the sensing arm was exposed.
A Michelson interferometer also has a sensing arm and a reference arm that propagate sensing and reference signals, respectively. However, in the Michelson interferometer these arms terminate in mirrors that cause the sensing and reference signals to traverse their respective optical paths twice before being combined to produce an interference pattern.
A hydrophone array is typically towed behind a ship. Towing causes vortexes, bubbles and other disturbances in the water that cause conventional hydrophones to give erroneous outputs. Most fiber optic hydrophones employ a matched Mach-Zehnder interferometer in the acoustic sensing system. One arm of the interferometer senses the acoustic field while the other arm is a reference. With a matched interferometer the reference arm can be placed next to the sensing arm so that any mechanical stresses applied to the sensing arm will also be applied to the reference arm.
A coating is applied to the jacket of the optical fiber in the reference arm to keep it from being sensitive to the acoustic field being measured. However, attempting to make the optical fiber in one arm of the interferometer insensitive to a particular physical parameter may also change other properties of the optical fiber. For example, coating the fiber jacket of one arm of the interferometer to change its sensitivity to the acoustic field changes the sensitivity of the optical fiber to acceleration. In such cases the effect of having matched arm lengths is not an advantage. Another difficulty with the matched pathlength interferometer is that coating the fiber jackets only partially eliminates the sensitivity of the fiber to the acoustic field and leaves a residual sensitivity that affects the performance of the sensor.
SUMMARY OF THE INVENTION
The present invention provides a mismatched pathlength fiber optic interferometer that has an inherent difference in the length of the sensing and reference arms. The arm length difference precludes the need to isolate the reference arm from the acoustic field. This difference in the length of the sensing and reference arms also permits the use of the reference arm as a device for cancelling out effects that accrue in the sensing arm. Keeping the jacket coatings the same on the reference arm and the sensing arm, allows the fibers to respond in the same manner. The sensitivity of the sensor is determined by the difference in the lengths of the two arms and by the type of material forming the mandrels around which the fibers are wrapped.
A method according to the present invention for forming a fiber optic sensor comprises the steps of providing a first mandrel section having a first longitudinal slot therein, placing a reference fiber within the slot and winding a sensing fiber around the first mandrel. The method of the invention also includes the steps of providing a second mandrel section having a second longitudinal slot therein, placing a spacer between the first and second mandrel sections, winding the sensing fiber and the reference fiber around the spacer, placing the reference fiber in the second longitudinal slot, and winding the sensing fiber around the second mandrel section.
The method of the present invention may further include the step of forming a plurality of sensing coils on each mandrel section. The method may also further include the steps of forming the first and second mandrel sections from nylon and forming the spacer from neoprene.
The method preferably includes the steps of providing a third mandrel, placing a spacer between the second and third mandrels, winding the sensing and reference fibers on the spacer, and winding the sensing fiber on the third mandrel.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of the fiber optic sensor according to the present invention; and
FIG. 2 illustrates reference and sensing fiber crossover between adjacent segments of the fiber optic sensor of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, a passive fiber optic sensor 10 includes three tubes 12-14 preferably formed of a material such as nylon. In a presently preferred embodiment of the invention, the tube 12 has a length of 20 cm and the tubes 13 and 14 have lengths of 13.3 cm. Referring to FIGS. 1 and 2, a spacer 16, preferably formed of neoprene is placed between the tubes 12 and 13, and a similar spacer 18 is placed between the tubes 13 and 14.
The fiber optic sensor 10 may include a mismatched pathlength Michelson fiber optic interferometer similar to that disclosed in U.S. Pat. No. 4,848,906 to Layton, which is hereby incorporated by reference into the present disclosure.
Referring to FIG. 1, the fiber optic sensor 10 includes a sensing fiber 20 and a reference fiber 22. A 2×2 coupler 24 is mounted to the tube 12 near an end 26 for coupling light between the sensing fiber 20 and the reference fiber 22.
A suitable structure for the fiber optic coupler 24 is described in the Mar. 29, 1980 issue of Electronics Letters, Vol. 18, No. 18., pp. 260-261. The fiber optic coupler structure is also described in U.S. Pat. No. 4,493,518 issued Jan. 15, 1985 to Shaw et al. and assigned to the Board of Trustees of the Leland Stanford Junior University. The disclosure of U.S. Pat. No. 4,493,518 is hereby incorporated by reference into this disclosure.
A first slot 28 extends longitudinally along the tube 12 from the coupler 24 to the other end 30 of the tube 12. A second slot 32 extends the entire length of the tube 13, and a third slot 34 extends the entire length of the tube 14. The tubes 12-14 are placed end-to-end with the slots 28, 32 and 34 aligned with each other.
Referring to FIG. 1, both the sensing fiber 20 and the reference fiber 22 extend from the coupler 24 and are placed in the slot 28. A few centimeters from the coupler 24, the sensing fiber 20 is led out of the slot 28 and wrapped around the tube 12 to form a first sensing coil section 36 that extends along the length of the tube 12 for about 3 cm. The first sensing coil section 36 has a very small pitch. A portion 40 of the sensing fiber 20 is then wound on the tube 12 with a pitch much greater than the pitch of the coils in the first fiber coil 36. The sensing fiber 20 is then wound on the tube 12 to form a second sensing coil section 42 that is essentially identical to the sensing coil section 36. The distance along the tube 12 between the first and second coil sections 36 and 42 may conveniently be about 0.5 cm. The second sensing coil section 42 ends near the end 30 of the tube 12.
Referring to FIGS. 1 and 2, a portion 22A of the reference fiber 22 is led from the slot 28 near the end 30 of the tube 12. The sensing fiber 20 and the reference fiber 22 are then placed closely together and wrapped around the spacer 16. The pitch of the wraps of the combined sensing fiber 20 and reference fiber 22 around the spacer 16 is preferably much greater than the pitch of the wraps of the sensing fiber 20 around the tube 12 to form the sensing coil sections 36 and 42.
Still referring to FIGS. 1 and 2, the sensing fiber 20 and the reference fiber 22 are separated again after they are wrapped around the spacer 16. A portion 22B of the reference fiber 22 is placed in the slot 32 in the tube 13, and the sensing fiber 20 is wrapped around the tube 13 to form third and fourth sensing coil sections 50 and 52, which are essentially identical to the sensing coil sections 36 and 42.
The sensing fiber 20 and the reference fiber 22 are then held together and wrapped around the spacer 18 in the same way as they are wrapped around the spacer 16. After being wrapped around the spacer 18, the reference fiber 22 is placed in the slot 34 in the tube 14. The sensing fiber 20 is then wrapped around the tube 14 to form fifth and sixth sensing coil sections 60 and 62, respectively. Thus the sensing fiber 20 is wrapped around the tubes 12-14 in a manner that cancels out acceleration noise while allowing the fiber optic sensor 10 to operate in an extended mode.
When the sensing fiber 20 and the reference fiber 22 cross together between adjacent tubes, the fibers experience essentially the same stress, which cancels out noise generated at the interfaces between the tubes. Instead of being in the slots 28, 32 and 34, the reference fiber 22 may be wrapped with the sensing fiber 20, but in a much larger pitch, to cancel out acceleration noise generated in the sensing coil 20.
Referring to FIG. 1, a mirror slot 68 is formed at the end 70 of the fiber optic sensor 10 where the slot 34 ends. The sensing fiber 20 and the reference fiber 22 are both secured in the slot 34 so that the fibers extend into the mirror slot 68. A small mirror 76 connected to the end of the sensing fiber 20 reflects light emitted from the sensing fiber 20 back toward the coupler 24. Similarly, a small mirror 78 connected to the reference fiber 22 reflects light emitted from the reference fiber 22 back toward the coupler 24. The light beams then combine in the coupler 24 to produce an interference pattern.
The fiber optic sensor 10 operates with light from a light source such as a laser (not shown). Light pulses are injected into the input fiber of the sensor 10. For purposes of explaining the method of operation of the fiber optic sensor 10 the input fiber is assumed to be the sensing fiber 20. The coupler 24 then divides the input light into two beams of substantially equal intensity so that both the sensing fiber 20 and the reference fiber 22 guide light pulses from the light source. The optical path through the sensing fiber 20 is considerably longer than the optical path through the reference fiber 22. The fiber optic sensor 10 has been found to function satisfactorily when the pathlength difference is about 73 meters.
The input light travels to the mirrors 76 and 78 and reflects back to the coupler 24, which combines the optical signals directed toward it from the sensing fiber 20 and the reference fiber 22. The signals in the sensing fiber 20 and the reference fiber 22 have a definite phase relationship when they exit the coupler 24.
The lengths of the sensing fiber 20 and the reference fiber 22 change as they are exposed to an acoustic field. These changes in length cause phase changes in the optical signals in the sensing fiber 20 and reference fiber 22. If the length of one of the arms of the interferometer changes more than the length of the other, then a signal is generated when the beams recombine in the coupler 24. The generated optical signal may then be guided by the reference fiber 22 to a detector (not shown) for producing electrical signals that may be processed to determine the magnitude of the acoustic disturbance that generated the signal.
The structures and methods disclosed herein illustrate the principles of the present invention. The invention may be embodied in other specific forms without departing from its spirit or essential characteristics. Therefore, the described embodiments are to to be considered in all respects as exemplary and illustrative rather than restrictive. Therefore, the appended claims rather than the foregoing description define the scope of the invention. All modifications to the embodiments described herein that come within the meaning and range of equivalence of the claims are embraced within the scope of the invention. | A fiber optic sensor is formed by providing a first mandrel section having a first longitudinal slot therein, placing a reference fiber within the slot and winding a sensing fiber around the first mandrel. The sensor includes a second mandrel section having a second longitudinal slot therein and a spacer between the first and second mandrel sections. The sensing fiber and the reference fibers are wound around the spacer, and then the reference fiber is placed in the second longitudinal slot. The sensing fiber is wound around the second mandrel section. The sensor may include additional mandrels and spacers to form additional sections. A plurality of sensing coils may be formed on each mandrel section. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to method and apparatus for feeding a conductive wire when a slide fastener chain provided with a conductive wire for anodizing process is produced. More particularly, the invention relates to improved method and apparatus by which a conductive wire can reliably be secured to the beaded portion of a slide fastener tape without breaking the wire.
Heretofore, U.S. Pat. No. 2,989,444 is known to show a device for feeding a conductive wire for anodizing process of a slide fastener chain. In this device, the wire is guided by a curved tubular fixed guide from a place spaced from the beaded portion of a fastener tape to a point adjacent the beaded portion, where it is secured to the beaded portion by an element to be fixed to the beaded portion. The device is adapted so that the conductive wire is advanced by rollers operating synchronously with the feeding movement of the tape. In such device, the portion of the conductive wire adjacent the beaded portion of the tape is a little tautened by frictional drag imparted from the curved tubular fixed guide. In this condition, when a fastener element is fixed to the beaded portion, the beaded portion deforms clamped by the legs of the element making the sections of the beaded portion between adjacent elements bulge. This results in increased tension in the portion of the wire extending between these elements and causes possibility of breaking the wire. A break in the wire also occurs when advancement of the tape and the wire is not completely synchronous. Furthermore, the drag imparted to the wire from the fixed guide as the wire is advanced increases the possibility of breaking the wire.
SUMMARY OF THE INVENTION
Therefore, it is an object of the invention to provide method and apparatus for feeding a conductive wire when a slide fastener chain provided with a conductive wire for anodizing process is produced, wherein the possibility of a break in the wire is minimized by providing appropriate slack in the portion of the wire adjacent the beaded portion of the fastener tape.
Another object of the invention is to provide method and apparatus for feeding a conductive wire, wherein the possibility of a break in the wire is minimized by reducing the drag imparted to the wire from means for guiding the wire.
According to the invention, a wire guide block reciprocates between a position adjacent the beaded portion of a tape and a position spaced therefrom. The distance between the upper end of a wire guide hole of the wire guide block and a lastly secured fastener element decreases as the wire guide block moves from the position spaced from the beaded portion of the tape to the position adjacent the beaded portion, thereby providing a slack in the conductive wire. Furthermore, the wire is so guided that it extends parallel with the feeding direction of the tape when the wire guide block is in the position adjacent the beaded portion of the tape and while this condition is kept the wire is fed concomitantly with the movement of the tape. Therefore, the wire guide hole causes little drag on the movement of the wire.
BRIEF DESCRIPTION OF THE DRAWINGS
The above mentioned and other objects and features of the invention will be clear from the following description referring to the drawings, wherein:
FIG. 1 is a plan view of a slide fastener stringer provided with a conductive wire for anodizing process;
FIG. 2 is a perspective view of an apparatus for securing fastener elements to the beaded portion of a fastener tape in which a wire feeding device according to one embodiment of this invention is incorporated;
FIG. 3 is a sectional view of the apparatus of FIG. 2 showing the condition in which a wire guide block is spaced from the fastener tape;
FIG. 4 is a sectional view of the apparatus of FIG. 2 showing the condition in which the wire guide block is adjacent the tape;
FIG. 5 is a plan view of a portion of the apparatus shown in FIG. 2 showing a way of squeezing the legs of a fastener element onto the beaded portion of the tape;
FIG. 6 is a perspective view of the wire guide block used in the apparatus of FIG. 2 with a portion being removed for clearly showing a wire guide hole therein; and
FIG. 7 is a schematic illustration showing the relation between the beaded portion of a fastener tape and a conductive wire in two different positions of the wire.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to FIG. 2, numeral 1 indicates an element forming die generally having the shape of inverted "L". The die is secured to the forward end of a main ram 2 which is horizontally reciprocated by suitable driving means (not shown). The element forming die 1 has a passage 3 extending vertically therethrough around the center of the die so that a formed wire F is fed through the passage. The element forming die 1 has a tape guide channel 4 formed in the front side thereof for guiding a slide fastener tape T. The forming die 1 is also provided with a head die portion 5 (FIGS. 3 and 4) at the forward end on the upper surface and adjacent the upper end of the guide channel 4.
A wire guide block 6 is secured to the forming die 1 at the lower portion thereof. The wire guide block 6 is formed with a channel 7 having a slant bottom wall in the center of the front side thereof. A conductive wire guide hole 8 for guiding a conductive wire W for anodization process is formed in the wire guide block 6 so that the hole opens at the bottom wall of the channel 7 and communicates with the tape guide channel 4. The opening of the guide hole 8 extends from the middle portion to the upper portion of the bottom of the channel 7.
Above the element forming die 1, a cutting punch 9 for cutting the formed wire F is fixedly connected to a frame or the like (not shown). The cutting punch 9 may be made movable. However, in any case, the cutting punch must be adapted to provide relative movement in horizontal direction with respect to the element forming die 1 when the latter horizontally moves. In front of this cutting punch 9, a vertically movable head forming punch 10 and a pressure pad 11 for holding a fastener element E during head forming operation are provided in a juxtaposed relation. In front of the cutting punch 9, there are also provided side punches 12 and 12' mounted on opposite sides of the tape guide channel 4 for reciprocation in generally lateral direction for squeezing the legs of the fastener element E.
A conductive wire W is passed through the wire guide hole 8 and secured to the beaded portion B of the tape T by the fastener elements E successively fixed to the beaded portion.
Tape guides 13 and 13' for guiding the slide fastener tape T are provided in front of the element forming die 1 and stoppers 14 and 14' are placed on the outer sides of the tape guides, respectively, to limit the forward movement of the element forming die 1 and to register the same. Feed rollers 15 and 15' (FIG. 2) for drawing the tape T upward are placed above the stoppers. The feeding direction and the orientation of the tape T are such that the wire guide block reciprocates perpendicularly to the feeding movement of the tape T in the plane including the tape. Numeral 16 (FIGS. 3 and 4) indicates feed rollers for feeding the formed wire F.
In operation, the formed wire F is upwardly fed by the amount corresponding to the thickness of one element E when the element forming die 1 is in its advanced position in which the cutting punch 9 does not interfere with the upward movement of the formed wire F. When the element forming die 1 retracts from the forward position shown in FIG. 4 to the backward position shown in FIG. 3, the formed wire F is cut by the cutting punch 9 to form a blank of an element E. When the element forming die 1 reaches its backward position, the head die portion 5 aligns with the head forming punch 10 and receives the cut blank of the element E. Then the head forming punch 10 and the pressure pad 11 descend to form the head of the element E and then the element forming die 1 starts forward movement. In the forward position of the element forming die 1 shown in FIG. 4, the legs of the element formed with the head receive the beaded portion B of the tape T therebetween. Then, the side punches 12 and 12' are driven to squeeze the legs of the element. By these steps, the element E are fixed to the beaded portion B together with the conductive wire W to form a fastener chain provided with a conductive wire for anodizing process as shown in FIG. 1. After the last mentioned step finishes, side punches 12 and 12' retreat and the tape T is advanced by one pitch and upwardly pulls the wire W.
The wire guide hole 8 in the wire guide block 6 is so positioned that the wire W guided by the hole 8 extends parallel with the feeding direction of the tape T and the wire portion adjacent the lastly secured element is brought into close contact with the beaded portion B when the element forming die 1 and the guide block 6 secured thereto are in their forward position. In other words, the guide hole 8 aligns with the direction of the wire movement. Therefore, the wire W can be pulled by the tape T with little drag from the guide hole 8. Therefore, the possibility of a break in the wire W is decreased. Furthermore, close contact between the wire W and the beaded portion B when the element E is secured to the beaded portion also reduces possibility of wire break. Furthermore, since feeding means for the wire W is unnecessary, there is no possibility of a break in the wire due to mis-synchronization between the operation of the wire feeding means and the tape movement.
The wire guide block 6 in this invention reciprocates perpendicularly to the feeding movement of the tape T in forward and backward directions toward and away from the tape T as illustrated by FIGS. 3 and 4. Accordingly, the portion of the wire between the upper end of the wire guide hole 8 and the lastly secured element E swings by angle θ as shown in FIG. 7. As is clear from this drawing,
l=L·cos θ
wherein l and L are distances between the upper end X of the wire guide hole 8 and the lastly secured element E in the forward and the backward positions of the wire guide block 6, respectively. Therefore, when the wire guide block 6 moves from the backward position to the forward position, the wire slackens by the degree corresponding to L(1-cos θ). As those skilled in the art will appreciate, the wire W is thin, lightweight, and very flexible in the conventional manner. Thus, forces of gravity and wire rigidity are not sufficient to cause the wire to retract through the hole 8 during the rapid reciprocable movement of the guide block 6. By this slack, the wire is not subjected to substantial tension when the lowermost section of the beaded portion B between adjacent element E, upon being clamped by the legs of the elements E, is bulgingly deformed. The reciprocal movement of the guide block 6 also functions to position the wire on the center of the beaded portion. That is, since the portion of the wire between the upper end X of the wire guide hole 8 and the element E is moved away from the beaded portion B each time after the element is fixed to the beaded portion, the wire portion is accurately positioned at the center of the beaded portion B when it is brought into contact therewith by the forward movement of the guide block 6. | Improved method and apparatus for feeding a conductive wire for anodizing process of a slide fastener chain are disclosed in which a wire guide member reciprocates perpendicularly to the feeding movement of the fastener tape so that the distance between the upper end of the guide member and the lastly secured fastener element decreases as the guide member moves from a position spaced from the beaded portion of the tape to a position close to the beaded portion, thereby giving appropriate slack to the wire. The fastener elements are secured to the beaded portion of the tape when the guide member is in the position close to the beaded edge. Therefore, possibility of breaking the wire is minimized. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates generally to textile apparatus for doffing and donning bobbins from a spinning or winding machine and, more particularly, to an apparatus for gripping and positioning a roving bobbin in proper drive connection on a winding spindle of a roving machine.
In conventional textile roving machines where roving is wound in relatively large packages onto elongate bobbins, the roving bobbins are supported on respective driven spindles of the roving machine in a positively driven fashion typically by the provision of mating drive components on the bobbins and winding spindles. Accordingly, it is necessary when doffing full roving packages from the roving machine and donning empty bobbons onto the vacated winding spindles that the proper drive connection between the mating components be correctly established. Ordinarily, the proper drive connection is achieved by initially placing the empty bobbin on the winding spindle and then rotating the bobbin with respect to the spindle as necessary to properly align and mate their driving components.
SUMMARY OF THE INVENTION
It is accordingly an object of the present invention to provide an automated apparatus for use in the doffing and donning of roving bobbins on a textile roving machine, by which the proper drive connection between the mating drive components of the bobbins and the spindles may be achieved in an automatic fashion.
Briefly described, the apparatus of the present invention basically includes a gripping arrangement for movement into and out of gripping engagement with a roving bobbin and an associated drive arrangement for selectively actuating such movements of the gripping arrangement. The drive arrangement is adapted for movement longitudinally with respect to the axis of a roving machine spindle for axial positioning of the gripped bobbin with respect to the spindle and is further adapted for rotational movement with respect to the axis of the spindle for orienting the drive component of the bobbin relative to the mating drive component of the spindle for proper driving connection thereof.
In the preferred embodiment of the present invention, the apparatus includes a housing adapted to axially receive one longitudinal end of the roving bobbin and the housing supports the gripping and drive arrangements for operation with respect to such bobbin end. The housing has a generally L-shaped guide slot formed therein with one extent of the slot oriented generally parallel to the axis of the bobbin and another extent of the slot oriented generally perpendicular to the first-mentioned extent. The drive arrangement includes a threaded drive spindle mounted on the housing with a drive nut arrangement threadedly supported on the drive spindle with an axial drive surface of the nut arrangement being provided for driving engagement with the gripped end of the bobbin. A guide component, preferably in the form of a guide roller, is mounted on the drive nut arrangement for movement within the L-shaped guide slot to determine movement of the drive nut arrangement either unitarily with the drive spindle or rotationally thereabout.
In one embodiment of the drive arrangement, the drive spindle is mounted to the housing against axial movement relative thereto and for selective reversible rotation thereto in opposite rotary directions. An electric motor is preferably provided for rotating the drive spindle in this embodiment. In another embodiment, the drive spindle is mounted to the housing against rotation relative thereto and for selective axial reciprocation relative thereto. In this embodiment, a fluid-operated piston-and-cylinder unit is preferably provided for reciprocating the drive spindle.
The gripping arrangement preferably comprises a plurality of gripping fingers arranged annularly about the axial drive surface of the drive nut arrangement and a thrust ring arranged within the housing annularly about the gripping fingers and in association with the drive nut arrangement for movement by the drive nut arrangement axially with respect to the housing for actuating movement of the gripping fingers into and out of gripping engagement with the bobbin end. The thrust ring is formed with a tapered cam surface for acting on the gripping fingers and with a shoulder for retaining the thrust ring within the housing. A spring is arranged within the housing between the thrust ring and the drive nut arrangement for biasing the thrust ring and the drive nut arrangement in axial relation to one another while permitting relative axial movement toward one another. The drive nut arrangement preferably includes a bushing forming the axial drive surface thereof with a friction ring formed on the bushing for driving engagement with the gripped end of the bobbin. The drive nut arrangment further includes a shoulder extending radially inwardly from an outward annular surface, with the shoulder engaging on end of the gripping fingers and with the thrust ring encircling the outer annular surface about the gripping fingers. One longitudinal end of the bobbin is provided with a recess therein for receiving an end of the drive spindle adjacent the axial drive surface of the drive nut arrangement.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view partially in side elevation and partially in vertical cross-section illustrating the preferred embodiment of the apparatus of the present invention in operative disposition gripping an empty roving bobbin in preparation for a donning operation;
FIG. 2 is a view similar to FIG. 1 depicting the present apparatus during the donning operation; and
FIG. 3 is a similar view to FIG. 1 illustrating another embodiment of the apparatus of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the accompanying drawings and initially to FIG. 1, the apparatus of the present invention includes a cylindrical housing 1 having an open lower end for receiving one longitudinal end of a roving bobbin 8, with a coarsely threaded spindle 2 rotatably mounted coaxially within the housing 1 and with an annular drive nut 3 threadedly supported on the spindle 2 within the housing 1. A gripping member 4 of an annular cage-like construction is supported annularly about the downwardly facing end of the drive nut 3 and a thrust ring 6 is supported within the housing 1 annularly about the gripping cage 4.
The housing 1 is formed with an L-shaped guide slot 9 having one vertical extent oriented substantially parallel to the axis of the housing and a horizontal extent 11 oriented substantially perpendicularly to the vertical extent 10. A guide roller 12 is mounted on the drive nut 3 to extend outwardly within the L-shaped guide slot 9.
The periphery of the drive nut 3 is of a step-like configuration with the lowermost end of the drive nut 3 being of a reduced diameter from which a shoulder surface 20 extends radially outwardly, with a cylindrical surface 21 extending axially from the shoulder 20. An annular bushing 19 is threadedly supported on the lowermost end of the drive nut 3 and the downward axial end face of the bushing 19 is fitted with a friction ring 7 formed of a material having a high coefficient of friction with respect to the bobbin 8. The gripping cage 4 includes a ring-like base mounted annularly about the bushing 19 in axial facing relation to the shoulder 20 of the drive nut 3, with a plurality of resilient spring-like gripping fingers 13 extending axially downwardly from the cage base annularly about the bushing 19. The thrust ring 6 is of an inner diameter corresponding to the outer diameter of the cylindrical surface 21 of the drive nut 3, the upper end of the thrust ring 6 being formed with a radially outwardly projecting shoulder 15 which axially faces a radially inwardly projecting shoulder 16 formed at the lower end of the housing 1. A helical coil-type spring 5 is disposed annularly about the cylindrical surface 21 of the drive nut 3 to extend axially between the drive nut 2 and the upper end of the thrust ring 6 to bias the drive nut 3 and thrust ring 6 away from one another into a normal relative axially spaced relationship. The downwardly projecting ends of the gripping fingers 13 are radially outwardly tapered, with the lower end of the thrust ring 6 being compatibly tapered outwardly at 14 to provide a cam surface.
The threaded spindle 2 is supported at its upper end by the housing 1 for selectively reversible rotational movement relative to the housing 1 in either opposite rotary direction, but is mounted against any axial movement with respect to the housing 1. A reversible electric motor 25 of a conventional construction is mounted on the upper end of the housing 1 in driving association with the spindle 2. The lowermost depending end of the threaded spindle 2 is provided with an unthreaded region 17 of a diameter that corresponds to an axial opening 18 formed at the upper end of the roving bobbin 8. The base of the bobbin 8 is formed with a drive recess 22 configured to receive a mated driving member 23 (FIG. 2) on the winding spindle 24 of a roving machine.
The overall apparatus of the present invention as described is suspended in depending fashion from a carriage 31 in a manner permitting limited movement of the apparatus axially toward and away from the bobbin 8. The housing 1 includes integral outwardly projecting flanges 32 which are received within oversized slots 33 in the carriage 31 by which a degree of axial movement of the present apparatus relative to the carriage 31 is permitted.
The operation of the present apparatus will thus be understood. In FIG. 1, the apparatus is depicted in gripping relationship with an empty bobbin 8 ready for donning onto a compatible spindle 24 (FIG. 2) of a conventional roving machine. As will be noted, the spindle 24 has been rotated to fully retract the drive nut 3 upwardly within the housing 1 with the guide roller 12 disposed at the upper end of the extent 10 of the L-shaped guide slot 9. Correspondingly, the gripping member 4 and the thrust ring 6 are also fully withdrawn within the housing 1, with the tapered cam surface 14 of the thrust ring 6 in engagement with the compatibly tapered surfaces of the gripping fingers 13 causing th fingers 13 to be moved radially inwardly to securely grip and retain the upper end of the bobbin 8 coaxially about the unthreaded portion 17 of the spindle 2.
Upon operation of the electric drive motor 25 in the appropriate rotary direction, the spindle 2 is caused to rotate and, in turn, actuates a positive downward movement of the drive nut 3 since the disposition of the guide roller 12 within the extent 10 of the L-shaped guide slot 9 prevents rotational movement of the drive nut 3 with the spindle 2. As will be understood, the bushing 19 and its friction ring 7 move downwardly integrally with the drive nut 3 and, simultaneously, the downward movement of the drive nut 3 produces corresponding downward movement of the gripping member 4, the coil spring 5 and the thrust ring 6, while retaining gripping engagment of the bobbin 8. Just prior to the completion of this downward motion of the drive nut 3 and related components, the shoulder 15 of the thrust ring 6 engages the shoulder 16 of the housing 1 to prevent any further downward movement of the thrust ring 6. Thereafter the coil spring 5 compresses to permit continuing downward movement of the drive nut 3 and the gripping cage 4. As the downward movement of the drive nut 3 is completed, the gripping member 4 moves axially downwardly with respect to the thrust ring 6 to disengage the gripping fingers 13 from the tapered cam surface 14 of the thrust ring 6, thereby releasing the roving bobbin 8, as depicted in FIG. 2.
At the completion of the downward motion of the drive nut 3, the base of the roving bobbin 8 rests on the drive member 23 of the winding spindle 24, normally with the bobbin drive recess 22 and the spindle drive member 24 out of mated engagement, as shown in FIG. 2, except in unusual circumstances when proper mated engagement occurs by chance coincidience. As the rotational movement of the threaded spindle 2 continues, the oversized slot 33 and the carriage 31 enable the entire apparatus to move axially as necessary until the guide roller 12 enters the horizontal extent 11 of the L-shaped guide slot 9, whereupon the drive nut 3 and related components rotate essentially unitarily with the spindle 2. As will be understood, the weight of the entire apparatus continues to be applied to the upper end of the roving bobbin 8, whereby the rotational movement of the drive nut 3 and its associated bushing 19 frictionally actuate corresponding rotational movement of the roving bobbin 8 until its drive recess 22 comes into proper mated engagement with the spindle drive member 23. Any continued rotation of the drive nut 3 and related components thereafter merely produces sliding movement of the bushing 19 and friction ring 7 with respect to the upper end of the bobbin 8 or the overall apparatus may move axially downwardly into resting engagement on the carriage 31.
In operation of the present apparatus for grasping and doffing a full roving bobbin, the apparatus while in its condition depicted in FIG. 2 is intially lowered over the upper end of a roving bobbin 8 to dispose the bobbin end within the gripping fingers 13 in end abutment with the friction ring 7 with the end opening 18 in the bobbin 8 coaxially aligned with the spindle 2. Upon reverse rotation of the threaded spindle 2, the drive nut 3 and associated components initially rotate with the spindle 2 while the guide roller 12 moves along the extent 11 of the L-shaped slot 9. Once the guide roller 12 reaches the juncture between the slot extents 10 and 11, further rotational movement of the drive nut 3 and associated components is prevented and such components begin to move upwardly along the spindle 2. Notably, at this point, the gripping fingers 13 are not as yet in gripping engagement with the roving bobbin 8. As such upward movement continues, the compression of the coil spring 5 is gradually released, whereby the thrust ring 6 does not move upwardly at the same rate as the gripping fingers 13 so that the tapered lower extent of the gripping fingers 13 gradually comes into engagement with the compatibly tapered cam surface 14 of the thrust ring 6 to force the gripping fingers 13 radially inwardly into gripping engagement with the upper end of the roving bobbin 8. As the upward movement of the drive nut 3 and the associated components continues, the gripped roving bobbin 8 is lifted upwardly and removed from its winding spindle 24.
As will thus be understood, the apparatus of the present invention uniquely provides for both rotational and longitudinal movement of the bobbin gripping components of the apparatus to insure efficient and reliable doffing and donning of roving bobbins on a textile roving machine while automatically providing for the establishment of positive driving connection between the mated drive components of the winding spindle and the roving bobbin. The provision of the helical coil spring 5 between the drive nut 3 and the thrust ring 6 assists in providing a flexible operation of the entire apparatus. Further, the formation of the spindle 2 with an unthreaded engagement end 17 for insertion within the axial end opening 18 of the roving bobbin 8 insures control of the proper desired upright orientation of the bobbin 8 and avoids possible tilting of the bobbin during the doffing and donning operation.
Referring now to FIG. 3, there is illustrated an alternative embodiment of the present apparatus wherein a pneumatically operated piston and cylinder unit is utilized as the means of driving the threaded spindle 2. In this embodiment, a piston 30 is reciprocably supported within a cylindrical chamber 38 for fluid-actuated reciprocal movement back and forth therein in a dual-acting manner by the introduction and exhaust of pressurized fluid at opposite sides of the piston 30 through inlet and outlet ports 36 and 38. The piston rod 35 is operatively connected coaxially with the threaded spindle 2 to actuate longitudinal reciprocation of the spindle 2. Thus, in contrast to the above-described embodiment of FIGS. 1 and 2, the spindle 2 in this embodiment is restrained against rotation relative to the housing 1 while being longitudinally reciprocable relative thereto. The construction and operation of the remaining components is otherwise substantially the same as in FIGS. 1 and 2.
In operation, the reciprocation of the piston 30 within the extent A of its longitudinal stroke will be understood to produce substantially unitary axial reciprocation of the threaded spindle 2 and the guide nut 3 and associated bobbin gripping components, inasmuch as the guide roller 12 remains within the vertical extent 10 of the L-shaped guide slot 9 throughout the extent A of the piston stroke. On the other hand, within the extent B of the piston stroke, the guide roller 12 is positioned to move within the horizontal extent 11 of the guide slot 9 whereby the drive nut 3 is prevented from axial movement with the spindle 2 and, accordingly, the axial spindle movement is converted into rotational movement of the drive nut 3 and its related gripping components, the gripping member 4, spring 5 and thrust ring 6.
It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of a broad utility and application. Many embodiments and adaptations of the present invention other than those herein, described, as well as many variations, modifications and equivalent arrangements will be apparent from or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to its preferred embodiment, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude any such other embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof. | Apparatus for use in doffing and donning roving bobbins on the winding spindles of textile roving machines, wherein a drive nut associated with bobbin gripping components is constrained by an L-shaped guide slot to move axially with respect to the bobbin spindle for positioning the bobbin axially with respect thereto and to further move rotationally with respect to the spindle to orient mating drive components of the bobbin and spindle in proper driving connection. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to an idle speed controller for an internal combustion engine for automobiles.
An internal combustion engine for automobiles has a throttle valve incorporated in an intake air passage thereof for controlling the amount of intake air thereby controlling output power and rotational speed of the engine. In an engine having a carburetor, the throttle valve is usually incorporated in the carburetor. The throttle valve is adapted to be opened or closed by operation of an accelerator pedal performed by the driver and when the accelerator pedal is released, the throttle valve is automatically driven towards a substantially closed idling position determined by an idle positioner. The conventional idle positioner generally comprises a set of co-operating abutting means, one being supported by a throttle lever for rotationally driving the throttle valve by engaging a throttle shaft which supports the throttle valve while the other abutting member is supported by a stationary structure such as the body of the carburetor. In this case, one of the two co-operating abutting members generally incorporates screw means therein for adjusting the abutting relation therebetween so as to allow the idling opening of the throttle valve to be adjusted by turning the screw means. In the conventional throttle positioner having this structure, the adjustment of the idling position is fixedly maintained or, in other words, no occasional re-adjustment of the idle position in accordance with changes in the operational conditions of the engine is automatically available or is manually available from the driver's seat.
However, in automobiles, particularly modern automobiles equipped with various auxiliary devices such as automatic transmission, power steering, air-conditioning, etc., the load imposed on the engine in idling operation varies by a large amount in accordance with the temperature condition of the engine and the ambient temperature. Therefore, when the idle position is fixedly adjusted by the conventional throttle positioner, the minimum throttle opening or idle opening must be set at a relatively large opening so as to ensure stable rotation of the engine in the highest idling load condition. However, such an adjustment causes too high idling rotation of the engine when the idling engine load is low as in the idling operation wherein the engine is sufficiently warmed up and the air conditioner is not used. Idling operation at too high rotational speed is very undesirable in view of the engine noise and fuel consumption.
Conventionally, engines generally incorporate a fast idle means adapted to operate in relation to a choke valve in the carburetor in order to facilitate cold-start-up of the engine. The fast idle means incorporates a bimetallic means and is adapted to increase the idle opening of the throttle valve when the engine is in cold state so as to increase the idling rotational speed thereby compensating for an increased idling load due to higher viscosity of lubricating oil in cold state and accelerating warming up of the engine. The conventional fast idling means is generally adapted to maintain the increased idle opening even after the engine has been warmed up if the throttle valve is not opened by stepping on the accelerator pedal in the course of warming up operation because although the bimetallic means responds to the warming up of the engine, a resetting of the idling position due to deformation of the bimetallic means can be effected only when the fast idle means has been released from engagement with the throttle valve or, actually, the throttle lever. Therefore, if an engine incorporating the conventional fast idle means is left in warming-up operation without occasionally stepping on the accelerator pedal, the idling speed gradually increases in accordance with warming up of the engine and finally it operates at a very high idling speed which causes very high engine noise and fuel consumption. Therefore, in the case of an engine incorporating such a fast idle means, the driver is required to occasionally step on the accelerator pedal in the course of warming up operation so as to occasionally release the fast idle means thereby allowing for resetting of the fast idle means step by step in accordance with gradual deformation of the bimetallic means.
In automobile engines, if the throttle valve is abruptly closed to the idle position by full release of the accelerator pedal while the engine is running at a relatively high speed, a high manifold vacuum is caused in the intake system of the engine whereby liquid fuel droplets attached to the inner wall surface of the intake passage violently evaporate and a large amount of fuel is drawn into the cylinders of the engine. On the other hand, since the flow of intake air is reduced by the closing of the throttle valve, the air/fuel ratio becomes too low, or too rich, thereby causing misfiring and delivery of a large amount of uncombusted components in the exhaust system. This causes the problem of air contamination and, furthermore, when secondary air is injected into the exhaust system for the purpose of purifying exhaust gases, combustion of uncombusted component occurs in the exhaust system and causes so-called afterfire. In order to avoid high emission of uncombusted components or occurrence of afterfire during deceleration in high-speed running, it has been proposed to incorporate a throttle control means such as throttle positioner, throttle opener, dashpot, etc., which temporarily increases the idle opening when the throttle valve has been abruptly closed after a long-lasting full open condition.
SUMMARY OF THE INVENTION
The primary object of the present invention is to provide an idle speed controller for internal combustion engines which controls idling rotational speed of the engine at a substantially constant value regardless of changes of engine idling load.
In accordance with the present invention, the abovementioned object is accomplished by providing an idle speed controller for an internal combustion engine having a throttle valve, comprising an idle positioner for setting idle position of said throttle valve, an actuator for biasing said idle positioner in the directions of opening and closing said throttle valve, a rotational speed sensor for detecting a signal which represents engine speed, and an operational control means for operating said actuator depending on rotational speed information received from said rotational speed sensor. By this arrangement, the idle position or idle opening of the throttle valve is adjusted by a feedback control means depending upon engine rotational speed so as to maintain a substantially constant rotational speed of the engine regardless of the load imposed on the engine.
As the signal which represents engine speed, an ignition signal in the engine ignition system, an electrical output signal generated by an electric pulse generating means incorporated in rotary portions of the engine such as the crankshaft, camshaft, etc. or other similar signals may be employed. The actuator may conveniently be a diaphragm actuator adapted to be actuated by a vacuum modified from the intake vacuum in accordance with the rotational speed of the engine by employing a vacuum modulation valve or the like.
Another object of the present invention is to provide an idle speed controller such as mentioned above which further comprises a thermal sensor for detecting warming-up condition of the engine by measuring the temperature of engine cooling water, lubrication oil, engine housing, etc. wherein said operational control means also responds to engine warming up information received from said thermal sensor for operating said actuator so that the idle position of the throttle valve is determined depending upon rotational speed of the engine and modified by engine warming-up condition. By this arrangement, the conventional fast idle means which requires occasional stepping on of the accelerator pedal during warming-up operation can be abolished.
Still another object of the present invention is to provide an idle speed controller having the abovementioned control system for controlling idle position of the throttle valve depending upon rotational speed of the engine and further incorporating a vacuum sensor for detecting intake manifold vacuum, wherein said operational control means is modified so as to operate said actuator depending upon rotational speed information received from said rotational speed sensor as well as manifold vacuum information received from said vacuum sensor, whereby the idle position of the throttle valve is controlled so as to maintain a substantially constant rotational speed of the engine while it is temporarily biased to an increased idle opening when said vacuum sensor detects an intake manifold vacuum larger than a predetermined value. By employing an idle speed controller of this type, the abovementioned conventional throttle positioner, throttle opener, dash-pot, or the like can be omitted.
BRIEF DESCRIPTION OF THE DRAWING
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only and are thus not limitative of the present invention and wherein:
FIG. 1 is a side view of a carburetor incorporating an embodiment of an idle speed controller of the present invention;
FIG. 2 is a diagrammatical sectional view showing a vacuum control system incorporated in the idle speed controller of the present invention;
FIG. 3 is a diagram showing an electrical control system incorporated in the idle speed controller of the present invention;
FIG. 4 is a set of graphs explaining the operation of the idle speed controller of the present invention;
FIG. 5 is a view similar to FIG. 4 explaining variations effected in the operation of the idle speed controller of the present invention;
FIG. 6 is a diagram similar to FIG. 3 showing a modification incorporated in the electrical control system;
FIG. 7 is a graph showing the performance of a thermistor;
FIG. 8 is a graph similar to FIG. 5 explaining another modification of operation of the idle speed controller of the present invention; and
FIG. 9 is a view similar to FIGS. 3 and 6 showing still another modification of the electrical control system.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now to FIG. 1, the body of a carburetor generally designated by reference numeral 1 has an intake passage 2 formed therein, in which is provided a disc-like throttle valve 3. The throttle valve is supported by a rotary throttle shaft 4 and is opened or closed by rotational operation of the throttle shaft. One end of the throttle shaft 4 projects outside from the body 1 and supports a throttle lever 5 mounted thereto. The thorttle shaft 4 is constantly biased to rotate clockwise as seen in the figure or to close the throttle valve by an expanding coil spring 7 mounted between a free end portion of the throttle lever and a lug member 6 mounted to the body 1. An acceleration control rod 8 engages the throttle lever adjacent its free end by a ball joint as shown in the figure. The above-explained structure is a conventional structure for opening or closing the throttle valve incorporated in usual carburetors.
In accordance with the present invention, a movable arm 10 is rotatably mounted to an end portion of the throttle shaft 4. The arm 10 has a stopped lug portion 12 at a middle portion thereof which is adapted to be abutted by an adjust screw 11 supported by the throttle lever 5. A compression coil spring 13 is provided for maintaining the adjusted position of the adjust screw 11.
The movable arm 10 is adjusted of its rotary position around the throttle shaft 4 by a diaphragm actuator 14 which as a casing 16 mounted to the carburetor body 1 by a bracket 15, a diaphragm 18 defining a diaphragm chamber 17 on one side thereof, a dish element 19 combined with the diaphragm, a compression coil spring 20 engaging said dish element at one end thereof so as to resiliently drive the diaphragm leftward in the figure and a rod 21 supported by said diaphragm at one end thereof and extended outside of said casing to be pivotably connected with a free end portion of the arm 10 by a pin 22 and a spring pin 23. The compression coil spring 20 operates to drive the arm 10 anti-clockwise or in the direction of opening the throttle valve by way of the diaphragm 18 and the rod 21. This driving force applied by the compression coil spring 20 is designed to be stronger than the driving force applied by the expansion coil spring 7 to drive the throttle valve clockwise in the figure or in the direction for closing the throttle valve in a manner such that when the diaphragm actuator is not supplied with any operating vacuum the force of the spring 20 overcomes the force of the spring 7 thereby establishing a relatively large idle opening for the throttle valve.
The diaphragm chamber 17 of the diaphragm actuator 14 is connected with a vacuum modulator 25 by a tube 24. The vacuum modulator is in turn connected with an intake vacuum take-out port 27 by means of a tube 26, said port being provided in the carburetor body to open to the intake passage 2.
As shown in FIG. 2, the vacuum modulator 25 comprises a housing 28 in which are mounted a solenoid 29, an armature 32 pivotably supported by a bracket 31 by a pivot pin 30, and two opposing nozzles 33 and 34 adapted to be controlled by said armature which operates as a flap valve. The nozzle 33 is opened to the atmosphere at the other end thereof, while the nozzle 34 is connected with the intake vacuum port 27 by way of the tube 26. The internal space of the housing 28 is connected with the diaphragm chamber 17 of the diaphragm actuator 14 by way of the tube 24. The armature or flapper nozzle 32 is biased upward in the figure by an expansion coil spring 35 so that it closes the nozzle 33 when the solenoid 29 is not energized. By this arrangement, when the solenoid 29 is not energized, the internal space of the housing 28 is prevented from communication with the atmosphere through the nozzle 33 and is substantially connected with the vacuum port 27 thereby transmitting intake vacuum to the diaphragm chamber 17 of the actuator 14, whereas when the solenoid 29 is energized, the internal space of the housing 28 is prevented from communication with the vacuum port 27 through the nozzle 34 and is opened to the atmosphere through the nozzle 33 thereby transmitting atmospheric pressure to the diaphragm chamber 17 of the actuator 14.
The operation of the solenoid 29 is controlled by an electronic control circuit 36 as shown in FIG. 3. The electronic control circuit receives an ignition signal from the primary circuit of the distributor 37. The electronic control circuit 26 comprises a wave-shaping circuit 38, a saw-wave generating circuit 39, a difference amplifier 40, a Zener diode 41 and a resistor 42. 43 designates a power source for the electronic control circuit 36 and may be the battery for the engine.
The idle speed controller shown in FIGS. 1-3 operates as follows:
FIG. 4(a) shows the ignition signal taken from the primary circuit of the distributor 37. This signal is supplied to the wave-shaping circuit 38 and is processed therein to produce a wave signal as shown in FIG. 4(b), which is a kind of trigger signal. This signal is then supplied to the saw-wave generating circuit 39 which generates a saw-wave signal as shown in FIG. 4(c). This is a signal which starts to increase from zero or a basic value upon receipt of a negative pulse in the trigger signal until the next negative pulse is dispatched, whereupon the signal at once returns to zero or the basic value and then again begins to increase. Such a signal is readily obtained by employing an integrating circuit. The saw-wave signal is supplied to the difference amplifier 40 which is also supplied with a constant voltage generated by the battery 43, Zener diode 41 and resistor 42. The difference amplifier 40 compares the saw-wave signal with said constant voltage and generates a pulse signal which is OFF when the saw wave signal is lower than said constant voltage and is ON when the saw wave signal is higher than said constant voltage, as shown in FIG. 4(d). This pulse signal is supplied to the solenoid 29 of the vacuum modulator 25.
The solenoid 29 is energized while said pulse signal is ON and draws the flapper valve 32 downwards in the figure, thereby closing the nozzle 34 while it opens the nozzle 33. When the pulse signal is OFF, the solenid 29 is de-energized, whereby the flapper valve 32 is biased upwards in the figure by the expansion coil spring 35 thereby closing the nozzle 33 while it opens the nozzle 34. When the solenoid 29 is cyclically energized and de-energized by the pulse signal as shown in FIG. 4(d) having the same frequency as the ignition effected in the engine, opening of the atmospheric pressure nozzle 33 and the vacuum nozzle 34 is alternated at a relatively high frequency, whereby the pressure in the housing 28 becomes a level intermediate between atmospheric pressure and the intake vacuum of the engine, said intermediate pressure being determined by the ratio of ON duration to OFF duration in the pulse signal. In more detail, when the duty ratio becomes larger, the vacuum in the housing 28 becomes smaller, while on the contrary when the duty ratio becomes smaller, the vacuum in the housing 28 becomes larger.
The vacuum generated in the housing 28 is transmitted to the diaphragm chamber 17 of the diaphragm actuator 14 by the tube 24 and biases the diaphragm 18 rightwards in the figure against the reaction of the compression coil spring 20. The displacement of the diaphragm is substantially proportional to the absolute value of the vacuum supplied to the diaphragm chamber 17.
When the absolute value of the vacuum supplied to the diaphragm chamber 17 is small, the diaphragm 18 is biased leftwards in the figure by the spring force of the compression coil spring 20 thereby driving the arm 10 by way of the rod 21 so as to rotate the arm 10 anti-clockwise in the figure around the throttle shaft 4 so that the lug 12 is driven toward the adjust screw 11, thereby establishing a relatively large idle opening for the throttle valve 3. As the absolute value of the vacuum supplied to the diaphragm chamber 17 increases, the diaphragm 18 is gradually driven rightward in the figure against the spring force of the compression coil spring 20 thereby retracting the arm 10 or the lug 12 from the adjust screw 11, thereby providing gradually reduced idle opening for the throttle valve. When the vacuum in the diaphragm chamber 17 becomes substantially the same as the vacuum in the intake passage 2, the arm 10 or the lug 12 moves to a position which provides the minimum idle opening for the throttle valve wherein it is substantially fully closed.
In the aforementioned manner, the idle position for the throttle valve is controlled depending on the rotational speed of the engine in a manner of feedback control.
FIG. 5 shows the way in which the saw wave signal and the pulse signal change in accordance with the rotational speed of the engine. In FIG. 5, signals (a) and (b) correspond to signals (c) and (d) in FIG. 4. Let us assume that the first wave and pulse in FIG. 5 are of the standard condition wherein the engine is idling at a standard speed. If the load imposed on the engine has increased due to an increase of the generator load, operation of an air conditioner, etc., idling speed of the engine will lower. If idling speed has lowered, period of the ignition signal taken from the distributor becomes longer, like the second saw wave in FIG. 5. This longer saw wave causes a longer ON duration in the pulse signal as in the second pulse of FIG. 5 thereby increasing the duty ratio of the pulse signal. If the duty ratio increases, the vacuum in the housing 28 is reduced thereby supplying a smaller vacuum to the diaphragm chamber 17 of the actuator 14, thereby causing a leftward movement of the diaphragm 18 which advances the idle position for the throttle valve toward a larger opening. Thus, engine output power is increased so as to compensate for the increase of load imposed upon the engine. On the other hand, when the load imposed on the engine operating in idling condition is reduced, idle speed of the engine increases and the period of the pulses in the ignition signal shortens. In this condition, the saw wave shortens and the duty ratio of the pulse signal is reduced like the third wave and pulse in FIG. 5. Therefore, the vacuum in the housing 28 increases thereby causing a rightward movement of the diaphragm 18 thereby retracting the lug 12 toward a position which establishes a smaller idle opening. Therefore, engine output power is reduced so as to meet with the reduced load imposed upon the engine.
When the engine is warmed up starting from the cold state, it is desirable that idling speed of the engine is a little higher than that in the warmed-up condition. The fast idle means is conventionally employed to temporarily increase idle speed during warming-up operation. In accordance with the present invention, such a temporary increase of idle speed for warming-up operation is readily obtained without employing the conventional fast idle means. FIG. 6 shows a modification of the electric control circuit 36 for obtaining the above-mentioned temporary increase in idle speed. In FIG. 6, 50 designates a thermistor adapted to detect a temperature which represents the temperature of the engine such as the temperature of the cooling water, etc. 51 is a resistor for adjusting the performance of the thermistor.
FIG. 7 shows general performance of the thermistor 50. The resistance of a thermistor generally reduces as the temperature thereof increases in a manner as shown in FIG. 7. Therefore, the comparison voltage supplied to the difference amplifier 40 increases as the temperature of the thermistor increases in a manner shown in FIG. 7. In more detail, the comparison voltage supplied to the difference amplifier 40 is relatively low when the engine is in the cold state and the comparison voltage gradually increases as the engine is warmed up. Therefore, when the engine is idling in the cold state, the saw-wave signal is compared with a relatively low comparison voltage, whereby a pulse signal having a relatively high duty ratio is generated as shown in FIG. 8. The high duty ratio produces a small vacuum in the housing 28 of the vacuum modulator 25 and causes a leftward biasing of the diaphragm 18 in the actuator 14 thereby advancing the lug 12 of the arm 10 toward a position for establishing a larger idle opening for the throttle valve.
As the engine is gradually warmed up, the thermistor 50 is correspondingly warmed up, thereby reducing its resistance, while the comparison voltage supplied to the difference amplifier 40 is correspondingly raised. Consequently, the duty ratio of the pulse output from the difference amplifier 40 is reduced and idle speed of the engine is correspondingly reduced. When the engine has been completely warmed up, idle speed of the engine is automatically adjusted to the standard value.
FIG. 9 shows still another modification of the electric control circuit 36 which further incorporates a means for preventing misfiring during deceleration of the automobile. In FIG. 9, 52 designates a pressure switch which is closed when intake manifold vacuum has increased beyond a predetermined value. 53 is a condenser and 54 is a resistor. In this arrangement, when the pressure switch 52 is closed, the comparison voltage supplied to the difference amplifier 40 becomes zero. In this condition, therefore, the idle opening for the throttle valve is made the maximum. This occurs when an automobile is decelerated when running at a relatively high speed with abrupt full closing of the throttle valve thereby causing a very high vacuum in the intake passage and manifold of the engine. When the engine has been decelerated so that intake manifold vacuum reduces below a predetermined value, the pressure switch 52 is opened and a normal comparison voltage is again supplied to the difference amplifier 40. On this occasion, the condenser 53 operates so as to gradually return the comparison voltage from zero to the normal level. By this arrangement, the throttle valve is maintained at a small opening rather than the substantially closed idle opening during high-speed deceleration of the automobile, thereby avoiding generation of over-rich fuel-air mixture due to a very high intake vacuum caused by high-speed deceleration, whereby troubles such as misfiring, afterburning, and high emission of harmful and uncombusted components are effectively avoided.
Although the invention has been shown and described with respect to some preferred embodiments thereof, it should be understood by those skilled in the art that various changes and omissions of the form and detail thereof may be made therein without departing from the scope of the invention. | An idle speed controller for internal combustion engines, having an adjustable idle positioner, an actuator for setting the idle positioner and a control means for operating the actuator, the control means being adapted to generate an output signal depending upon an input signal representing engine speed so as to accomplish a feedback control of engine idling speed. | 5 |
BACKGROUND OF THE INVENTION
This is a continuation-in-part of application Ser. No. 873,546 filed June 12, 1986, now U.S. Pat. No. 4,685,222, which is a continuation-in-part of application Ser. No. 666,674 filed Oct. 31, 1984, now U.S. Pat. No. 4,594,797.
This invention relates to an air heater and blower assembly for discharging air at a generally uniform velocity along the length of an elongated slot. More in particular the invention relates to a surface mounted apparatus for drying large wet surfaces such as the full human torso upon bathing.
It is well known to use portable air heaters and blowers to discharge air at a relatively high velocity for drying. For example, portable hair and hand dryers are of this type.
It is also known, from U.S. Pat. No. 3,878,621, to Duerre, to use a heater in a bathroom having elongated slots for drying the human body and hair.
It is also known to use a flexible hose in combination with an air heater and blower as shown in U.S. Pat. No. 3,449,838, to Chancellor, Jr. Another type of body drying apparatus is shown in U.S. Pat. No. 3,621,199 to Goldstein. Here, the whole body of a person may be dried by the passage of hot air; a deflector is arranged to deflect a stream of hot air from an outlet, the deflector being oscillated so as to cause the stream of air to sweep upward and downward over the body.
Other U.S. patents relate to an after-shower body dryer, as shown in the patent to Hudon, U.S. Pat. No. 3,128,161 showing a plurality of heated air outlets with air being heated by an element and a blower being arranged in a conduit to provide the air supply. In U.S. Pat. No. 2,977,455 to Murphy, a body dryer is shown having an electrical heating element, switches arranged together with other structure for use in blowing heated air across a human body. A perforated plate is used to distribute the air across a central portion of the plate.
In another type of device, heated air is used in combination with a blower to inflate generally flexible, flaccid bag members so as to rub against the body of a person, the bag being generally absorbant and porous. Here, contact of a human body with the bag while the bag is inflated with heated air, causes drying by physical contact of the bag member with the body together with air flow carrying moisture away from the bag member. Some convection moisture removal will be caused by the generally low air flow speed through the bag member, however, this is not the primary drying mode.
SUMMARY OF INVENTION
The invention is an apparatus for providing drying air which might be used in place of a towel for drying off after taking a shower, hence, the commercial name of the invention is AIR TOWEL™. The invention is for drying an entire person rather than portions of a body, such as hands, feet, or hair; however, it can be constructed to dry such portions. The invention is constructed to be mounted on a surface without having to recess the unit into a mounting surface.
The invention comprises three elements. Means for providing air for drying is located preferably above the unit and more preferably within the ceiling above the invention. The means for providing air includes a vent for supplying air, a heater for heating the air, and a blower for providing a flow of air.
An elongated chamber is attached to the means for providing air. The elongated chamber has a diminishing cross section from a point of attachment to the means for providing air to a distal most point from the means for providing air. The tapered chamber is provided with an elongated passageway formed on one wall of the chamber which provides a passageway for air flowing out of the chamber and into exterior areas where people can position themselves for receiving drying air. The chamber is preferably composed of a front and a back, both of which have side walls which can overlap to provide an enclosed chamber. The front and back of the chamber fit together much akin to a shoe-box top fitting on a shoe-box. The front of the chamber is provided with the passageway which is an elongated slot about four or more feet in length. Air flowing into the chamber from the means for providing air will exit the chamber through the passageway in a generally uniform rate all along the length of the passageway because of the diminishing cross section of the chamber. Thus, a wet person desiring to get dried needs to merely position himself in front of the passageway and air exiting the entire length of the passageway will provide a flow of air upon a substantial portion of the length of the person.
Means are provided for connecting the AIR TOWEL™ to a mounting surface. Preferably the means for attachment is a cover for the chamber. Situated upon the cover is an elongated slot coextensive with the chamber's passageway. The cover is provided with side edges which are substantially coplanar with the back of the chamber. Fasteners may be used to attach the side edges to the mounting surface. The cover preferably has a recess located on the cover which is adjacent to the air passageway. Lying within the recess is a flexible hose which has an inlet connected to the means for supplying air. The hose has an outlet where nozzle means is attached. The nozzle means is used for directing a flow of air to a limited amount of area such as, for example, hair. When the flexible hose is not being used it lies within the recess located on the cover. Also on the cover is located an actuator for the means for providing the air. The actuator is preferably a button to actuate the blower-heating elements to start the flow of air. Preferably, a pneumatic line sends a signal to a conventional temperature controller to actuate a relay which would close a circuit to selectively turn on or off the blower and heater elements. A control line communicates a control signal to an electrical supply which powers the motor. The material composing the air chamber and cover is preferably an electrically insulated material such as a thermoplastic.
It is an object of the invention to provide an easily installed surface mountable apparatus for drying large surface areas such as a human or animal torso.
These and other and further objects and features of the invention are apparent in the disclosure, which includes the foregoing and following specification, claims and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
While the specification concludes with claims particularly pointing out and distinctively claiming the subject matter that is regarded as forming the present invention, it is believed that the invention will be better understood from the following description accompanied by the following drawings in which:
FIG. 1 is an elevated exploded perspective of the invention;
FIG. 2 is an elevated perspective showing the invention in partial cutaway;
FIG. 3 is a cross-sectional view taken from line 3--3 on FIG. 2;
FIG. 4 is a cross-sectional view taken from line 4--4 on FIG. 2;
FIG. 5 is a cross-sectional view taken from line 5--5 on FIG. 2;
FIG. 6 is a cross-sectional view taken from line 6--6 on FIG. 2;
FIG. 7 is an elevated side plan view of the invention in partial cutaway; and
FIG. 8 is an elevated perspective of an alternative embodiment of cover 22 from FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The best mode for practicing the invention is set out in FIG. 1. The surface-mountable apparatus for drying is shown in the elevated exploded perspective as having three parts. Part 1 is the back of the surface-mountable unit and is shown as having planar surface 10 having lateral sides 11 and 12 bent perpendicular to planar surface 10. Planar surface 10 is shown as being wider at end 13 than end 14. End 14 has side 15 which is bent perpendicular to the planar surface 10. End 13 is shown as being open.
Piece 8 provides the front of the chamber. Piece 8 has a planar surface 16 which has lateral sides 17 and 18 which are bent perpendicular to the planar surface 16. The front of the chamber 8 fits to chamber 1 so that the lateral sides 11, 12, 17, and 18 connect. The lateral sides maintain the planar surfaces 10 and 16 in mutually spaced relationship. It is to be noted that the lateral sides may be connected by any suitable means. Such means can be welding, glueing, fastening with threaded fasteners, or interference fittings. A combination of connecting means may be used to connect the lateral sides. For example, lateral side 17 can overlap lateral side 11 and glueing or heat bonding can be used to further secure the interference fit. The lateral side 18 may overlap lateral side 12 in similar fashion.
The back 1 and the front 8 when pieced together form the chamber for the drying apparatus. The tapering sides of planar surfaces 10 and 16 give the chamber 1, 8 a generally diminishing cross section from end 13 to end 14.
The front 8 of the chamber is provided with an elongated passageway 19. The passageway 19 provides an air outlet for the chamber, 1 and 8. Air entering the inlet of chamber 1,8 at the wider end 13 exits the chamber through passageway 19. Air departing from the chamber through passageway 19 has a constant velocity all along the length of the passageway 19 because of the diminishing cross sectional areas of the chamber 1,8.
The passageway 19 is shown as having sides 20 and 21 which project from planar surface 16 in a perpendicular fashion but may also be venturied or angled. It is to be noted that the sides of passageway 19 do not have to project outward from the planar surface 9 as illustrated with sides 20 and 21. The invention can be practiced quite easily by having passageway 19 be an elongated through-hole in planar surface 16. Cover 22 is provided for encasing chamber 1,8 and for attaching chamber 1,2 to a surface. Cover 22 is adapted to fit over back 1 and front 8 such that the hole 23 on cover 22 is coextensive with the passageway 19 on front 8. Cover 22 has sides 24 and 25 which are bent perpendicular to the planar surface 26 but may also be venturied or angled. The cover 22 is attached to the chamber 1,8 by connecting sides 24 and 25 to sides 20 and 21 in a fashion similar to the way sides 17 and 18 are connected to sides 11 and 12. It is to be noted that sides 20, 21 and 24, 25 can be eliminated so that planar surface 16 can be attached to the back of planar surface 26 such that hole 23 is coextensive with passageway 19. The cover 22 may also be bonded to portions surrounding hole 34.
Cover 22 is provided with an edge 27 which forms a border around cover 22. When cover 22 is attached to chamber 1,8, edge 27 is substantially coplanar with the back planar surface 10. Holes 28, 29, 30, and 31 located on edge 27 are adapted to receive fastening means for attaching the cover 22 to a surface. Any kind of fastening means may be used to attach cover 22 to a surface. Such fastening means may be nails, screws, bolts, molly bolts, rivets, hooks, etc. The fastening means will vary with the type of surface. For example, tile surfaces will require different fastening means than gypsum board.
Cover 22 is also provided with a recess 32 which is shown as being elongated. The recess 32 has a first end 33 and a second end 63. The first end 33 is open, (not shown). The opening is in communication with hole 34 located on back 1. FIG. 2 shows a flexible hose 35 lying within recess 32 wherein the hose 35 is connected to end 33 and thus to hole 34. FIG. 2 also shows hose 35 having nozzle means 36 for controlling the direction and flow of air through hose 35.
Cover 22 also shows another recessed area 37 which has been added to cover 22 for aesthetic purposes. Located on recess 37 is actuating means 38. The actuating means 38 can be a button provided to actuate the blower and heating means to provide air to the chamber 1,8. The actuation is more fully disclosed in commonly owned U.S. Pat. No. 4,594,797 issued to Houck, Jr. which is hereby incorporated in its entirety herein.
FIG. 8 shows an alternative embodiment to cover 22 as shown in FIG. 1. The cover 220 of FIG. 8 is preferred when the invention is to be recessed in a mounting surface such that the planar surface 260 is substantially coplanar with the mounting surface, i.e., flush mounted. The edges 27 and 57 of FIG. 1 is not necessary for the embodiment of FIG. 8, and therefore is left off cover 220.
Preferably, a hole is cut in the mounting surface to accomodate the air chamber 1,8 so that sides 680 and 690 fit flush to the surface on which the cover 220 is mounted. Fastening means are used in conjunction with holes 280, 290, 300 and 310 for attaching cover 220 to the mounting surface. All other structures on cover 220 are substantially the same as on cover 22.
FIG. 2 is a elevated perspective view of the invention as it would be seen attached to a mounting surface such as a wall. FIG. 2 is shown in partial cutaway for clarity of disclosure.
As can be seen, cover 22 is visible and back 1 and front 8 are encased therein. Cover 22 is attached to mounting surface 39 in FIG. 7. The invention is simply attached to a surface so that air passageway 19 discharges the air in the preferred direction. It is preferable that air passageway 19 be arranged so as to provide a flow of air along a substantial portion of a torso. Air hose 35 is shown as resting within recess 32.
The invention is usually mounted below a ceiling 40 as shown in FIG. 2 and FIG. 7. Means for providing air 41, 42, 43, 44, 45, 46, and 47 is situated in an out-of-the-way place such as above ceiling 40. Ductwork 49 depends from the ceiling 40 and attaches to the invention at or about point 50. The ductwork 49 is provided with a cover 51 which preferably matches the cover 22 to provide a uniform aesthetic appearance. Cover 51 is provided with attaching means 52. Attaching means 52 is an edge corresponding to edge 27 and has holes 53, 54, 55, and 56 for attachment to mounting surface 39 by any fastening means. FIG. 1 shows the ledge 57 on cover 22 for receiving in overlapping relationship a portion of cover 51. Other methods for connecting cover 22 with cover 51 may be used; however, it is preferred that all visible portions of the invention fit together in a cooperative relation providing for aesthetics as well as for functionality.
The means for providing heated air is best shown in FIG. 2. The return air grill 48 provides communication between an area containing air and the air plenum 41 which is preferably a sheet metal duct work. Air duct 42 provides communication between the air plenum 41 and the heating element 43. Air duct 44 provides communication between heating unit 43 and blower 45. The control box 47 contains the electronics for actuating the invention. Wires are shown running from control box 47 to access plates 64 and 65 on the motor 46 and heating element 43, respectively. Duct work 67 channels air from the blower 45 to duct work 49 which in turn is connected to chamber 58. (see FIGS. 3, 4, 5 and 6.)
In operation, air is drawn into air plenum 41 through return air grill 48, by way of blower 45 forcing air downward through ducts 67 and 49. Air flows through duct 42 where it is heated by the heating element in heating unit 43. Heated air then flows through duct 44, blower 45, ducts 67 and 49, and out passageway 19 and/or nozzle 36.
Actuating means 38 is a pneumatic button connected to control box 47 preferably by a 1/4" diameter hose. Air forced through the hose (not shown) activates the switches for the motor and heating elements. Quick disconnect switch 66 is provided for safety purposes when maintenance is required. When the desired heat is attained, the heat can be turned off by pushing the pneumatic button. Air continues to flow until the drying cycle is completed.
FIGS. 3, 4, 5, and 6 show one of the salient features of the invention. The chamber space itself is denoted by the number 58. FIG. 3 is a cross section taken from about the top of the invention where the chamber is shown to extend from side 59 to side 60. It is to be noted that sides 59 and 60 are where back 1 and front 8 connect. There is also connection 61 connecting the air chamber 58 to cover 22. Also shown is edge 27 for attaching the invention to mounting surface 39. Air passageway 19 is shown as being blocked by cover 22.
FIG. 4 is another cross section of the invention disclosed in FIG. 2 taken at line 4--4. The chamber space 58 is shown as having a diminished cross section when compared to FIG. 3. The passageway 19 opens to exterior areas. Instead of the hose attachment hole 34 as shown in FIGS. 1 and 3, FIG. 4,5 and 6 show hose 35 hanging in recess 32.
FIG. 5 is yet another cross section of the invention as disclosed in FIG. 2 taken along line 5--5. The chamber 58 is shown as being even more diminished in cross section when compared to the chamber space of FIG. 4.
FIG. 6 is still another cross section of the invention as disclosed in FIG. 2 taken along line 6--6 of FIG. 2. The chamber space 58 is even more diminished in cross section as compared to the other FIGS. 3 thru 5. The invention achieves a generally uniform rate of flow of air traveling through passageway 19 from chamber space 58 all along the length of passageway 19. That is to say, the air departing passageway 19 in FIG. 6 has the same general rate of flow as air departing passageway 19 in FIG. 4.
FIG. 7 is an elevated side plan view of the invention shown attached to a mounting surface such as a wall. Covers 51 and 22 are shown with their edges 52 and 27 being attached to a mounting surface such as wall 39 by way of fasteners 62. The fasteners may by any kind of fasteners. The ductwork 49 is shown as depending from the ceiling 40. The vent 48 is shown as providing the supply of air used to flow through the chamber 58.
The preferred material for constructing the components of the air chamber is a moldable thermoplastic. Back 1, front 8, and cover 22 are preferably all made from a thermoplastic material. It is conceivable that back 1, front 8 and cover 22 may all be molded as one piece. It is preferred, however, that the back, front, and cover be constructed of 3 separate pieces of material. The back 1 and front 8 can be used for a unit which is to be recessed into a mounting surface. It should be noted however, that the more convenient surfaces for providing the invention often times do not allow for a recessed embodiment of this invention. Such surfaces are brick, tile, concrete, etc. The surface-mounted unit as presently disclosed is for such instances where fast and easy installment is desired.
One of the most convenient ways for making the components 1, 8, and 22 of the invention is by thermo-forming. Sheets of ABS material (acrylonitrile, butadiene, styrene) are deformed by hot presses into desirable shapes. The ABS material can be anywhere from 3/16" thick to pieces much thicker. The material has a fire retardant plastic filler, mechanical toughness for impact which remains to minus -60° F. and has chemical resistance.
The invention is referred to as an AIR TOWEL™. Installation of the surface mountable unit is simple. The blower motor unit 41, 42, 43, 44, 45, 46, 47 and optionally 48 is mounted on a platform in the ceiling; however, it can be mounted in other locations. Ductwork is attached to the blower motor unit and the AIR TOWEL™. The AIR TOWEL™ is attached to a mounting surface in close proximity to bathing areas.
The invention is not limited in size. It is conceivable that it can be reduced in size and mounted for use as a hand dryer. The invention is advantageous over present hand dryers because the invention, even if only provided with about a 10" slot provides more air per surface area to be dried than conventional hand dryers. It is conceivable the invention can be enlarged to dry large animals, e.g., horses.
As this invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, the present embodiment is therefore illustrative and not restrictive, and since the scope of the invention is defined by the appended claims, all changes that fall within the metes and bounds of the claims or that form their functional as well as their conjointly cooperative equivalents are therefore intended to be embraced by those claims. | A surface mountable device for drying bathers has an enclosed, vertically or horizontally oriented chamber. An elongated air passageway is located on the front of the chamber. Means for providing drying air is attached to one end of the chamber. The chamber has cross sections which diminish from the end attached to the means for providing drying air to the opposite end. The cover has attachment means for attaching the device to a desired surface, obviating the necessity for recessing the device in the surface. | 0 |
TECHNICAL FIELD OF THE INVENTION
[0001] The invention relates to a door of the type with an apron that can be moved by electromechanical drive means between a closed position and an open position.
[0002] The invention relates more particularly to flexible apron doors of e.g. folding or wind-up type designed to obstruct or open an opening formed in a wall separating two areas.
BRIEF DISCUSSION OF RELATED ART
[0003] In these applications, the speeds at which the apron is driven for opening or closing are high. It is therefore necessary to provide safety systems associated with the door, notably to prevent injury or damage in the event of an accidental collision between the apron and a person or object.
[0004] For this purpose, in a known embodiment, the apron comprises obstacle-detection means connected to the control device of the electromechanical drive means. Thus for example, when the apron hits an obstacle during its closing movement, a signal is sent to the control device which can then act on the electromechanical drive means to stop the closing movement and possibly move the apron back in the opening direction.
[0005] The link between the obstacle-detection means and the control device may be a wire. If so, the cable employed is connected at a first end to a moving structure (the apron) and at a second end to a fixed structure (the control device or to an intermediate point on the wall to which the door is fixed).
[0006] Consequently, every time the apron is opened and closed, the cable is itself moved back and forth, at high speed. At its ends, the cable is particularly stressed and has to twist in order to follow the movement of the apron. As a result, the cable is severely fatigued and therefore at risk of breaking, at which point the safety of the door is no longer assured. This fatigue phenomenon is made the more acute by the fact that the apron is operated a very large number of times in a day.
[0007] Moreover, a moving person or object, such as a goods handling truck, may become caught in the cable and pull it at least partly free from the door. This risk is increased if the cable is already weakened as explained above. Once again, the consequence would be the loss of the door's safety system.
BRIEF SUMMARY OF THE INVENTION
[0008] The invention improves the connection between the obstacle-detection means and the control device by providing a door that has a wire link which is reliable, robust and safe, and is thus able to meet the new safety standards.
[0009] For this purpose, the invention relates to a door comprising a frame defining an opening. The frame is designed to be fixed to a wall, said frame defining an opening and comprising two essentially vertical lateral jambs. The apron can be moved by electromechanical drive means mounted on the frame between a closed position in which the apron obstructs the opening, and an open position in which the opening is unobstructed; the apron comprising obstacle-detection means connected by a wire link to a device which controls the electromechanical drive means, and the wire link comprising a cable whose first end is connected to the apron and whose second end is connected to the frame.
[0010] The door is more particularly characterized in that it comprises at least one connector connecting the first end of the cable to the apron or the second end of the cable to the frame, said connector being mounted on either a region of the apron or on a region of the frame, in such a way that it is able to rotate about an axis approximately perpendicular to said region and being separable, when pulled, into two reconnectable parts, in such a way as to detach the end of the cable from either the apron or the frame, respectively.
[0011] The concept of the invention is thus to provide the cable with a connector which orients itself automatically to suit the position of the apron, in such a way that the cable is in the most direct possible position between the apron and the frame. Since the pivoting is now confined to the connector, the cable is not subjected to twisting. The service life of the cable is thus increased and, since the risk of breakage is reduced, the safety of the door is improved. Furthermore, if a person or machine catches against the cable, then above a certain traction force, the cable will simply “pop out” of the apron (or frame) and will not be ripped out. It can therefore be put back in the operating position very quickly and easily by hand without the use of any special tools.
[0012] The door may comprise a single connector connecting the first end of the cable to the apron, while the second end of the cable is directly connected to the frame, without an intermediate connector, or a single connector connecting the second end of the cable to the frame, while the first end of the cable is directly connected to the apron, without an intermediate connector.
[0013] In one embodiment of the door according to the invention, the door comprises a first connector connecting the first end of the cable to the apron and a second connector connecting the second end of the cable to the frame, said connectors being essentially identical.
[0014] Each end of the cable can thus pivot relative to the door: twisting, and therefore cable wear, are thus minimized.
[0015] To minimize the length of cable necessary for proper operation of the door and safety system, the second connector may be mounted on a jamb, approximately halfway up said jamb, while the first connector is mounted on the apron close to the lateral edge of the apron adjacent to said jamb.
[0016] In a variant, the door comprises an approximately horizontal upper hood beneath which the apron can be housed in the open position, and the second end of the cable is connected to said hood and the first end of the cable is connected to the apron by a connector so arranged that the cable is approximately vertical when the apron is closed, said connector being designed not to interfere with the positioning of the apron beneath the hood when open.
[0017] The connection between the connector and the apron, or between it and the frame, may be a ball joint.
[0018] This connection, by giving greater freedom of movement to the connector, further reduces the wear on the cable.
[0019] In one embodiment the connector comprises a ring mounted on the apron, or on the frame, and an elbow piece having a first arm mounted approximately coaxially relative to the ring in such a way that it can rotate about the axis of the ring, and having a second arm which receives detachably a pin attached to the end of the cable.
[0020] Additionally, the first arm of the elbow piece may be fixed to a cylindrical bush mounted approximately coaxially in the ring, said cylindrical bush being able to pivot about its axis.
[0021] In one advantageous provision, the cable is in the form of an elastically extensible helix.
[0022] This makes the cable compact. It also does not dangle and does not pull too much on either the apron or the frame, wherever the apron is between the open and closed positions.
[0023] In the case of a high-speed door, the apron is formed by a flexible plastic sheet or an assembly of flexible plastic sheets.
[0024] The door may also include means for immobilizing the apron in a predetermined position, said means being coupled to the electromechanical drive means and controlled by the separation of the connector into its two reconnectable parts. Separation of the two parts of the connector therefore leads to the apron either stopping in the position in which it happens to be at the moment, or moving to a stop position which is selected to suit the application (for example the open position).
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] To explain the invention clearly, it will now be described again with reference to the attached figures which show, by way of non-restricted example, one possible embodiment of the door.
[0026] FIG. 1 is a schematic front view of a door according to the invention, showing the frame and the apron in the closed position;
[0027] FIG. 2 is a partial enlarged perspective view of the lower part of the door, apron closed, showing the wire link and the connectors, one connector on one of the jambs of the frame and the other on the apron;
[0028] FIG. 3 is a partial enlarged perspective view of the upper part of the door, apron open, showing the wire link and the same connectors;
[0029] FIG. 4 is an enlarged view of the detail marked IV in FIG. 2 ;
[0030] FIG. 5 is an enlarged view of the detail marked V in FIG. 3 ;
[0031] FIG. 6 is a side view of the apron, showing a protective shell around the connector; and
[0032] FIG. 7 is a front view of the apron shown in FIG. 6 equipped with the shell.
DETAILED DESCRIPTION OF THE INVENTION
[0033] The door 1 comprises a frame 2 fixed to a wall 3 defining an opening, and a flexible apron 4 to close the opening.
[0034] The frame 2 has two vertical jambs 5 , 6 and a horizontal upper crossmember 7 forming a hood containing a horizontal shaft 8 on which the apron 4 is wound and unwound to open or close the opening. The shaft 8 may be turned about its axis, via reducing gears 9 , by an electric motor 10 controlled by an electronic control device 11 . A manual control box 12 connected to the control device 11 may be provided on the wall 3 beside the door 1 , and allows a user to open or close the opening.
[0035] The apron 4 is a flexible sheet made of a plastic, such as PVC, and includes horizontal reinforcing bars 13 . The apron 4 also has a flexible deformable weighted sill bar 14 , which contains obstacle-detection means (not shown). These obstacle-detection means may consist for example of an infrared beam which can be cut by a projecting part when the sill bar 14 is deformed as a result of an impact, or may consist of two slats which come into contact when struck by an obstacle and thus allow an electric current flow.
[0036] The apron 4 can be moved between a high position, in which it is completely wound onto the shaft 8 and the opening is completely unobstructed, and a low position in which it is completely unwound and the opening is obstructed. These movements of the apron 4 are performed at high speed, many times a day.
[0037] To facilitate these movements, the jambs 5 , 6 comprise, on their inside face 15 —that is, their face nearest the apron 4 —two longitudinal ribs 16 , 17 defining a track 18 between them in which the lateral edges of the apron 4 are guided when the apron 4 is moving.
[0038] A wire link connects the obstacle-detection means to the control device 11 so that, for example, when an obstacle is encountered when the apron 4 is on its way down, the motor 10 is tripped to stop the movement of the apron 4 or open it.
[0039] The wire link comprises in succession a conductor (not shown) connecting, inside the sill bar 14 ′ the obstacle-detection means to a first connector 19 mounted on the apron 4 , an external cable 20 connected at a first end 21 to the first connector 19 and at a second end 22 to a second connector 23 mounted on the jamb 6 , and a conductor 24 housed at least partly inside the jamb 6 to connect the second connector 23 to the control device 11 .
[0040] The second connector 23 is mounted on a jamb (jamb 6 in this case) at a point about halfway up the jamb 6 , while the first connector 19 is mounted on the lower part of the apron 4 , on the sill bar 14 , near the lateral edge of the apron 4 adjacent to the jamb 6 . As a result, the distance between the two connectors 19 , 23 does not exceed one half of the height of the apron 4 , regardless of whether the apron is at the top or bottom. This limits the length of cable 20 required and also limits the deformation of the cable 20 .
[0041] In addition, the second connector 23 is mounted on the inside face 15 of the jamb 6 . The cable 20 is therefore situated in the immediate vicinity of the apron 4 and does not project from the door 1 beyond the thickness of the jambs 5 , 6 . This limits the risk of a person or object catching against the cable 20 .
[0042] The cable 20 is in the form of an elastically extensible helix, like a telephone cable, whose length at rest (when the turns are closed up) is less than half the height of the jambs 5 , 6 . Hence, when the apron 4 is either open or closed, the cable 20 is slightly stretched and does not offer any dangling parts that could be easily caught.
[0043] The connector 23 will now be described in more detail with reference to FIGS. 4 and 5 .
[0044] The connector 23 comprises a ring 25 fixed, for example by screws, to the inside face 15 of the jamb 6 so that its axis 26 is perpendicular to the inside face 15 . A cylindrical bush 27 is mounted in the orifice of the ring 25 , essentially coaxially, so as to be able to pivot about its axis 26 .
[0045] The connector 23 also includes an elbow piece 28 comprising first and second hollow cylindrical arms 29 , 30 of identical cross section. The second arm 30 is perpendicular to the first arm 29 and longer. The first arm 29 comprises, at its end not connected to the second arm 30 , a transverse square plate 31 fixed to the cylindrical bush 27 so that the axis of the first arm 29 coincides with the axis 26 of the ring 25 . The axis 32 of the second arm 30 is thus parallel to the inside face 15 of the jamb 6 .
[0046] Lastly, the connector 23 comprises a cylindrical pin 33 whose outside diameter is slightly less than the inside diameter of the second arm 30 of the elbow piece 28 . One end of the pin 33 is attached to the second end 22 of the cable 20 , while its opposite end is intended to be inserted like a male plug into the second arm 30 to make electrical contact with the conductor 24 via the elbow piece 28 .
[0047] The pin 33 and the elbow piece 28 can be separated from each other by simply pulling on the pin 33 , above a certain load. This can happen accidentally when a moving person or object catches against the cable 20 and pulls it. However, the cable 20 can be reconnected very easily to the conductor 24 by pushing the pin 33 back into the elbow piece 28 .
[0048] The first connector 19 is identical to the second conductor 23 , and is mounted as follows: the ring 25 is fixed to the apron 4 in such a way that its axis 34 is perpendicular to the plane of the apron 4 ; the axis of the first arm 29 of the elbow piece 28 coincides with the axis 34 of the ring 25 ; and the axis 35 of the second arm 30 is parallel to the plane of the apron 4 . The pin 33 is on the one hand attached to the first end 21 of the cable 20 and on the other hand engaged, at its opposite end, in the second arm 30 of the elbow piece 28 , thus making electrical contact with the conductor connected to the obstacle-detection means, via the elbow piece 28 .
[0049] Because of the structure, the connectors 19 , 23 can pivot about the axes 34 , 26 of the rings 25 . They thus orientate themselves automatically depending on the position of the apron 4 :
when the apron 4 is in the low position ( FIGS. 2 and 4 ), the first end 21 of the cable 20 is situated lower than the second end 22 and the cable 20 is at its most stretched. The second arm 30 of the first connector 19 points up and the second arm 30 of the second connector 23 points down, while the axes 35 , 32 are approximately collinear and approximately coincide with the axis of the cable 20 ; when the apron 4 is being moved toward its high position, the first end 21 of the cable 20 is moved translationally along an ascending vertical path. The first end 21 steadily approaches the second end 22 until their heights are the same, after which it moves steadily past it as the movement continues. During this movement the apparent length of the cable 20 decreases because of its elasticity, until the turns are in mutual contact. Then, when the distance between the connectors 19 , 23 is less than the length at rest of the cable 20 , one portion of the cable 20 begins to dangle. The length of this portion reaches its maximum when the two connectors 19 , 23 are both of the same height, after which it reduces as the ascending movement continues, until finally vanishing. By the end of the movement the cable 20 is once again stretched. During this movement, also, the connectors 19 , 23 pivot about the axes 34 , 26 , respectively, so as to follow the movement of the apron 4 and cable 20 . When the cable is stretched and therefore straight, it forces the connectors 19 , 23 to pivot until the axes 35 , 32 are approximately collinear and approximately coincide with the axis of the cable 20 ; and when the apron 4 is in the high position ( FIGS. 3 and 5 ), the second end 22 of the cable 20 is situated lower than the first end 21 and the cable 20 is at its most stretched. The second arm 30 of the first connector 19 points down and the second arm 30 of the second connector 23 points up, the axes 35 , 32 being approximately collinear and approximately coinciding with the axis of the cable 20 .
[0053] A cable 20 tension maintaining system may be provided, e.g. a seatbelt-type winder or a tensioning system using a weight acting via a turn pulley (when the apron is open, the cable and its weight are at their lowest position inside the jamb, and when the apron is closed, the cable and its weight are at their highest position inside the jamb).
[0054] Additionally, as depicted in FIGS. 6 and 7 , the door 1 may comprise a protective shell 36 mounted removably on the apron 4 around the first end 21 of the cable 20 and around the first connector 19 , so as to form with the apron 4 an essentially hermetic enclosure. “Essentially hermetic” here means that the first connector 19 and the region of connection between the cable 20 and the apron 4 are protected from dust and trickling water.
[0055] For this purpose the shell 36 is rounded in shape and has a generally smooth outer surface. This shape allows water to run off when the door is exposed to the weather, and it also limits the risk of the shell 36 catching against anything, even in an impact.
[0056] Similarly, of course, a shell 36 may be provided for the second end 22 of the cable 20 .
[0057] The invention thus represents a decisive improvement on the prior art by providing a door with a robust and durable safety system.
[0058] It goes without saying that the invention is not limited to the embodiment described above by way of example but that on the contrary it encompasses all alternative embodiments thereof. | The invention relates to a door comprising a frame and an apron ( 4 ) which can be moved by drive means between a closed position and an open position. The apron comprises obstacle-detection means which are connected by a cable ( 20 ) to a device for controlling the drive means. A first end ( 21 ) of the cable is associated with the. apron, while the second end ( 22 ) thereof is associated with the frame. The first and/or second end(s) of the cable comprise(s) a connector ( 19,23 ) which is mounted to an area of the apron or the frame such that it can rotate around an axis ( 26, 34 ) that is perpendicular to said area and which can be separated into two reconnectable parts by means of pulling. In this way, it is possible to detect one end of the cable associated with the apron or the frame. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention concerns a method and device for the rapid depositing of oxydes in thin layers which adhere well to plastic supports.
2. Description of the Prior Art
It is known that there are several methods making it possible to deposit thin layers on a substrate. One of the best known methods, providing very adhesive layers is cathode sputtering. Nevertheless, the depositing speed is very slow, since it reaches about a hundredth of a micron per minute in the best cases and it is not possible to adapt that method to really industrial applications for large mass-producing operations. Another method which is also well-known consists in forming deposits by evaporation of the material to be deposited. That method makes it possible to operate at a very much higher depositing speed, but the layers thus deposited on the plastic support only very rarely give the user satisfaction.
The present invention aims at developing and applying a method, recently perfected, consisting in forming with the oxide to be sprayed, a plasma in an arc state and in spraying it onto the substrate kept in a vacuum.
Layers having excellent quality are thus obtained at a depositing speed 50 to 100 times higher than with cathode sputtering. It is known that according to that recent method, the discharge in an arc medium is induced within a cavity whose walls are lined with the material to be deposited. That cavity is drilled with an opening putting it into communication with the enclosure containing the substrate. When the arc medium is established, the particles of the material to be deposited are driven out of the cavity through the opening formed in the latter, penetrate in the enclosure where a lower pressure than in the cavity prevails, and come into contact with the substrate and are deposited thereon.
It is known that the discharge is an arc state thus set up has a tendency to increase in intensity if the latter is not controlled.
SUMMARY OF THE INVENTION
The aim which the inventor had in view when developing that oxyde depositing technology was to obtain a satisfactory evenness of the oxyde layer on a large plastic surface, as well as the slightest possible heating up of the plastic support, it being understood, moreover, that the layer thus obtained always retained all its adhesive qualities which the method used enables, whatever the type of the plastic substrate used may be and lastly that the depositing speed remained very high or was even improved each time this was possible.
According to the invention, the method perfected has for its object the rapid depositing of oxides in thin and adhesive layers on plastic substrates arranged in an enclosure kept under vacuum, opposite the circular opening of a source cavity internally lined with the oxides to be deposited, the said source cavity being kept, by means of injected oxygen, at a pressure higher than that prevailing in the enclosure, a plasma in an arc state being formed in the said source cavity by the high-frequency excitation of an induction coil surrounding the said source cavity, characterized in that to obtain an even layer, on the one hand, the arc state of the discharge is stabilized and on the other hand, the plastic supports to be coated are moved away from the said circular opening 17 along the axis of the latter.
The discharge in an arc state which is set up in a device applying the aforementioned method tends to increase in intensity, to rapidly set up vaporing of the material lining the cavity to modify the depositing state and more particularly to alter the evenness of the layer deposited. The stabilizing of the arc state is therefore a necessary condition to achieving evenness of the layers. Circumstances therefore lead to the compulsory introducing of a means for stabilizing the arc. Moreover, having observed that for a given structure of the device, the evenness of the layer deposited increased with the distance at which the plastic support was placed from the circular opening of the cavity, the inventor has been induced to impart to the structure of the device a particular shape making it possible to bring the distance between the circular opening of the cavity and the plastic support to 500 mm and more, this being nearly 10 times the diameter of the cavity. For the free flow of the particles of the material to be deposited to be sufficient, it is necessary to reduce the pressure in the enclosure while maintaining a pressure 10 to 100 times higher within the cavity, that condition enabling simultaneously the increasing of the depositing speed in very appreciable proportions. Lastly, by moving the plastic support away from the opening circular opening of the cavity, the heating up thereof is simultaneously reduced.
In this way, the device implementing the method according to the invention, enabling the rapid depositing of thin and adhesive layers of oxides on the surface of plastic supports is constituted by:
an enclosure provided with a pumping unit ensuring a high vacuum to the enclosure;
a source cavity cylinder internally lined with a layer of oxide to be deposited, closed at its lower part by a plug through which a gas injection tube passes and provided, at its top, with a circular axial opening, an excitation winding of the source cavity formed by turns of a conductor tube internally cooled and electrically connected to an oscillating circuit provided with adjusting means;
a starter placed at the level of the source cavity;
a plastic substrate fixed on a substrate support and placed substantially on the axis of the axial circular opening of the source cavity cylinder and facing the opening;
characterized in that the distance between the substrate to be coated and the axial circular opening of the source cavity cylinder is greater than several times the diameter of the said source cavity cylinder.
The upper part of the enclosure is generally cylindrical and its diameter itself is also greater than several times the diameter of the source cavity cylinder.
The lower part of the enclosure in the vicinity of the source cavity cylinder may, on the contrary, have a diameter which is nearly the same as or slightly greater than that of the cavity. In that case, the connection of the upper part of the enclosure with the lower part is effected by means of a truncated cone whose wall opens at an angle of 60° or more.
The lower part of the enclosure in the vicinity of the cavity may, on the contrary, have the same diameter as the upper part, the enclosure as a whole then having the shape of a cylinder whose diameter is that of the upper part of the enclosure whose lateral walls are spaced apart from the source cavity. The electromagnetic field is then concentrated within the source cavity cylinder by a concentration means formed essentially by two concentric conductive cylinders electrically connected together, constituting the secondary winding of an impedance transformer whose primary winding is formed by the induction coil. In this way, it may be considered that in all cases, an induction coil is placed in the immediate vicinity of the cavity, either inside the enclosure or outside the latter. The stabilization of the current may be obtained as previously by inserting in the primary winding a fixed inductance. That stabilization has also been obtained by inserting a regulator of a known type, in the feeding of the primary circuit and by controlling it with a voltage by a tap at the terminals of a turn of the primary winding.
DESCRIPTION OF THE DRAWING
The example of embodiment described hereinbelow and the digital values, given by way of an example having no limiting character, concerning the depositing of silica on plastic supports by deposits of various oxides such as, more particularly, chromium oxide, tin oxide, and indium oxide, have been formed on plastic supports without making appreciable modifications to the apparatus implemented so that the following description may have a general character all although it is made with reference to:
The single FIGURE showing diagrammatically an installation for depositing a thin layer of silica at the surface of a support made of a plastic material.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A cylindrical casing surrounding the source cavity 2 may be seen at 1. According to one embodiment, the induction coil 3 is shown in the form of two turns of a hollow conductor inside which a cooling fluid flows. The cylindrical casing 1 extends, in its upper part, by a circular plate 5 drilled with an opening 6. The casing 7 or source cavity cylinder forming the source cavity supports, at its upper part, a fluid-tight ring 8 preventing the ingress of polluting substances into the induction coil 3. In other embodiments (not shown), the induction coil is situated outside the cylindrical casing 1 surrounding the source cavity 2, but then, a means for concentrating the field is applied inside the enclosure and the turn of the said concentrator which is the nearest of the source cavity 2 is cooled directly or indirectly by a circuit of cooling fluid, so that in general cases, the wall of cylinder 7 of the cavity is cooled.
Internally, the source cavity cylinder 7 is lined with one or more cylinders 10 of silica; the bottom of the source cavity cylinder 7 is covered with a silica washer 11 drilled with an opening 12 at which a tube 14 supporting, by means of the plate 32, the cylinder 7 of the source cavity terminates. That tube is used for injecting the gas, in this case oxygen; its discharge is regulated by a microvalve 15. A silica washer 16 completes the forming of upper part of the cavity. That washer 16 carries a circular driller axial opening 17 centred on the circular opening 6.
The circular plate 5 limiting the cylindrical part of the enclosure 1 is connected in a fluid-tight manner to a truncated cone shaped casing 18 which tapers upwards and whose axial cross-section open at an angle of more than 60°.
The upper end of the truncated cone shaped casing 18 is extended horizontally by a circular plate 20 on which rests the upper part 21 of the enclosure through an O-ring 22. That element 21 assumes the form of an inverted draining tank. At its centre, the upper part a1 of the enclosure supports an axle or shaft 23, supporting the substrate support 24 and in turn the substrate 29. A circular flange 25 makes it possible to connect up the pumping tube 26 to the enclosure, tube 26 being provided with a valve 27 and connected to the pumping unit 28 having a high discharge capable of providing a vacuum of less than 10 - 6 Torr.
The enclosure is therefore constituted by the cylindrical tube 1 bearing in a fluid tight manner on a support plate 32, extended by the truncated cone shaped casing 18 which tapers upwards and connects up at its upper part 21 of the enclosure.
The installation most frequently used has the following dimensions:
the source cavity cylinder has a diameter of 50 mm on the outside and 30 mm on the inside;
the circular opening 12 drilled in the upper disk 16 is 10 mm. The total height of the source cavity 2 is 50 mm.
the distance between the circular opening 17 and the substrate is adjustable between 200 mm (the substrate support being sunk into the truncated cone shaped casing 18) and more than 500 mm (the substrate 29 being in the upper part 21 of the enclosure).
The electric circuitry used makes it possible to stabilize the intensity of the discharge of the arc which is indispensable for any industrial operation of the device. The high-frequency oscillating circuit comprises a self-inductance 33, a reaction self-inductance 35 connected in series with the induction turn 3 in the oscillating circuit which may be adjusted by the capacity 34. The adjustment for power is effected by a self-transformer (not shown). When the arc state is reached, the induction turn 3 may be considered as being in short-circuit; the total self inductance of the circuit becomes the sum of the self inductances 33 and 35; the impedance of the oscillating circuit decreases slightly, so that the anode current increases only slightly (in the order of 10 percent) instead of causing the racing of the rate, which would not fail to occur with a circuitry in which the induction turn is not connected in series with a high impedance.
The priming of the discharge is obtained through a starter arranged on the outside or on the inside of the enclosure, at the level of the cavity.
The operation of the device requires firstly the setting up in the enclosure of a vacuum in the order of 10 - 6 Torr. Then, oxygen is brought into the source cavity 2 to form a pressure in the order of 2 to 7.10 - 3 Torr therein, the pressure in the cavity which depends on the diameter of the circular opening 17 of the source cavity 2 and on the discharge of the pumps 28 is set up in the present case according to the discharge of these latter at a value comprised between 2.10 - 5 Torr to 7.10 - 4 Torr, the first value being preferred, as much because of the higher depositing speed observed as because of the high pressure gradient which appears at the opening of the cavity. Nevertheless, it is sufficient for the ratio between the pressures to be in the order of 10, the pressure in the enclosure under vacuum being, for example, 7.10 - 4 Torr and whereas the pressure in the cavity is 7.10 - 3 Torr. The gradient of the pressures thus obtained is then sufficient to reach a perfectly even adhesive and rapid deposit of the oxide on the substrate.
When these pressures are reached and a high-frequency adjustable between 2 and 6 Mc/s is applied, the rate which is formed as soon as priming is obtained by means of the starter 36 in the cold discharge rate, causes the plasma to have a light blue colour. After a certain time, the plasma becomes enriched; it turns a very intense blue colour, rich in ultra-violet rays; the arc state is primed and depositing in the arc state begins.
Throughout the whole operation, the anode voltage remains constant and equal in general to 6 KV in the aforementioned circuitry. The anode current which is 1 ampere without load assumes the value of 1.1 ampere when the plasma is formed and reaches 1.4 ampere in the arc state due to the limiting of the current imposed by the self inductance. These few experimental details make it possible for the man in the art to convince himself thoroughly that the process observed is totally different from cathode sputtering in an oxygen plasma.
The deposits obtained easily reach a thickness of 3 microns while remaining perfectly homogenous and adhesive.
In the axis of the source, a depositing speed in the order of 2 microns per minute at a distance of about 200 mm from the source has been observed. The depositing speed decreases with the axial distance, increase between the substrate and the source cavity, and it is no longer greater than 0.5 micron per minute at an axial distance of 400 mm, this being absolutely normal because of the angle of opening of the plasma beam leaving the circular opening of the source cavity.
The distribution in space of the thickness of the deposit on a plane substrate closely follows the ideal curve of the law of the emission in a cosine for a source having a small surface. It is observed that the law is all the better followed as the axial distance between the substrate and the circular opening of the source cavity is made larger. Thus, at an axial distance of 200 mm, the deviation between the ideal curve and the thickness measured is 20 percent but at a distance of 500 mm, the deviation is no more than 5 percent.
For a source cavity having a diameter of 50 mm, it is therefore an advantage to place the substrate an axial distance from the cavity opening at least equal to 4 times the diameter of the cavity.
At 200 mm, depositing is rapid, but the variation of the thicknesses is still fairly far away from the ideal curve. At 400 mm, (8 times the diameter of the source cavity) the depositing speed is still in the order of half a micron per minute and the variation in thickness of the deposit is less than 10 percent from the ideal layer. At 500 mm (10 times the diameter of the source cavity) the depositing speed is less than half a micron per minute but on the other hand the continuity of thickness is virtually perfect.
These last two distances have been selected as preferred limits.
The operations for depositing layers on plastic materials having a determined shape can be effected in a way which constitutes an advantage only if the temperature of the substrate does not reach high values liable to produce any alteration in shapes. At the distances selected, the temperature of the substrates never exceeds 50° C.
The quality of the deposits has been examined under two other aspects:
its resistance to weather, cold, rain, wind, sun, dust, has been tested during several months but without any alteration in the deposit having been observed with a microscope.
The resistance to abrasion has been determined by the rubbing of a organic body loaded with grains of abrasive material whose pressure on the layer is determined by additional weights which tend to press the frication surface against the sample.
It has been observed that the majority of plastic substances on which experiments were carried out on the bare substance were scored as soon as the additional weight reached 10 grammes.
On the other hand, the scores did not appear on a deposit of 2 microns having a thickness of 2 microns except with additional weights of 200 grammes.
Lastly, on a deposit having a thickness of 3 microns, it has been possible to make scores appear even with an additional weight of more than 800 g.
These various experiments and the technology perfected show that it is possible now to effect according to the method and the device described above, the coating with a layer thin but perfectly protective and transparent layer of silica, of various objects of an industrial nature, such as glasses for spectacles, and watches, screens, masks and helmets for motor-cycle riders, pilots, etc., cockpits for cars, aeroplanes, wind screens, etc.
Although the device which has just been described may appear to afford the greatest advantages for the implementing of the invention in a particular technical situation, it will be understood that various modifications may be made thereto by the man in the art without going beyond the scope of the invention, more particularly when it is required to obtain a homogenous deposit of oxyde on a surface having a particular shape or a simultaneous deposit on the two sides of a substrate made of a plastic material. | An apparatus consisting in forming, with the oxide to be sprayed on, a plasma in an arc state within a source cavity. The state is stabilized by various known methods but which are well-adapted and the substrate to be covered is preferably kept at a predetermined distance, in order of 50 cm, from the source cavity.
A positive pressure gas is supplied to the source cavity and vacuum pressure is maintained in the enclosure supporting the substrate facing the cavity opening to deposit oxide uniformly at high speed. | 2 |
BACKGROUND OF THE PRESENT INVENTION
[0001] Field of Invention
[0002] The present invention relates mining machinery, and more particularly to a center pillar and full face vertical shaft drilling machine.
[0003] Description of Related Arts
[0004] Existing shaft sinking methods has experienced long-term development. The method of shaft sinking mainly includes drilling and blasting, shaft boring and etc. The construction technology has matured. The shaft sinking equipment also experienced the same development and the equipment technology has matured also. Follow the traditional construction method makes it very difficult to realize automation, and it is very difficult for parallel operation while the labor requirement is great. After numerous improvements, the shaft sinking equipment technology of our nation has matured. It is very difficult to further improve the construction efficiency through the advancement of one single equipment, thus a brand new equipment is urgently needed to increase the construction efficiency.
SUMMARY OF THE PRESENT INVENTION
[0005] An objective of the present invention is to overcome the problems of existing devices and provide a center pillar and full face vertical shaft drilling machine which has high level of automation and mechanization for vertical shaft construction, thereby the construction time is fast and safe, the vertical shaft construction for a large diameter and a great depth can be achieved and the construction cost is relatively low.
[0006] In order to solve the above problem, the technological solution is provided as follows:
[0007] In one aspect of the present invention, it provides a center pillar and full face vertical shaft drilling machine which comprises a center pillar, a device platform, a derrick, a boring system, a transportation system for people and materials, a support system for wall reinforcement system, a safety system and a control room, characterized in that, a derrick is provided at a shaft head on which the control room is located, the center pillar extended from a shaft bottom to the shaft head directly while connecting to a sliding frame of the derrick, the boring system is installed at a front end of the center pillar, and on the center pillar sequentially from a rear end to the front end installed a plurality of device platforms, a transportation system for people and materials, and the safety system is installed on the device platform located a rear end of the boring system and the ground surface, the support system for wall reinforcement system is installed on the device platform located at the rear end of the boring system and its surrounding.
[0008] The center pillar comprises a plurality segments of main body, each having a hollow columnar structure, connected through flanges and fastening members to form the center pillar, wherein a primary hoist rail, a secondary hoist rail, a cable, a compressed air pipe, a concrete pipe, a clean water pipe, a pipe for slurry outflow, a pipe for slurry inflow and a mounting base for stabilizer are arranged along the peripheral edges of the main body of the center pillar, the hollow portion of the center pillar defines a passage for a ventilation and water passage module of the safety system, the safety system comprises a fan installed directly at an inner side of the center pillar.
[0009] The device platform comprises a fixed platform; and a retractable platform which is installed in a segment of module lining of the center pillar, wherein the retractable platform comprises a base platform, a small platform, a retractable cylinder and a seal member, wherein the base platform is fixedly connected to the center pillar and the retractable cylinder is fixedly provided around a peripheral edge portion of the base platform horizontally, wherein the retractable cylinder comprises a piston shaft and is connected to the small platform through one end of the piston shaft, wherein the small platform has an outer portion at which the seal member is provided, wherein the seal member has an outer end which is in contact with the module lining of the center pillar.
[0010] The derrick comprises a main body of derrick, a sliding frame, an pillar for sliding frame, a lifting cylinder, a movement arrangement, a crane for pillar, a manipulator for pillar, a power station and a muck chute; wherein the main body of derrick has a lower portion at which the movement arrangement is provided and an upper portion at which the pillar for sliding frame and the power station are installed, wherein the pillar for sliding frame guides a sliding movement of the sliding frame, wherein the lifting cylinder has one end connected to the sliding frame and another end connected to a bottom end of the pillar for sliding frame, wherein the crane for pillar is installed on the upper portion of the main body of derrick, wherein the manipulator for pillar and the muck chute are inclined and installed at the lower portion of the main body of derrick.
[0011] The boring system for the vertical shaft drilling comprises a cutter head with rear mounting construction, a retractable shield, a shield positioning ring, a main driver, a shield cylinder, a guiding pillar, a propulsion cylinder, a gripper sliding ring, a gripper and a gripper cylinder; wherein the cutter head is connected to the main driver, the main driver has an upper portion connecting to the guiding pillar, the guiding pillar has a upper portion connecting to the center pillar, the main driver is connected to the shield positioning ring, the shield positioning ring is connected to the retractable shield through telescopic structure and the shield cylinder to form a ring-shaped retractable shield, the guiding pillar has a key structure and has a sliding connection with the gripper sliding ring while both the guiding pillar and the gripper sliding ring are connected through the plurality of propulsion cylinders provided around all sides, the gripper is connected to the gripper sliding ring through telescopic structure and the gripper cylinder, the control station is installed on an upper portion the gripper.
[0012] The transportation system for people and materials comprises a slurry pump, a slurry inflow pipe, a slurry outflow pipe, a primary vibrating screen, a secondary vibrating screen, a tertiary vibrating screen, a primary hydrocyclone device, a secondary hydrocyclone device, a muck storage, a slurry storage tank, a rapid feeding device, a bucket, a main hoist, an auxiliary hoist, a slurry return pipe, a transportation pump, a slurry output pipe, a slurry input pipe, a primary slurry pump, a secondary slurry pump, a primary slurry tank, a secondary slurry tank and a cage; wherein the slurry pump is installed inside the main driver, the slurry inflow pipe is extended to inside the cutter head, the slurry outflow pipe has an inlet connected to the slurry pump and an outlet connected to the primary vibrating screen, the primary vibrating screen has a slag outlet corresponding to the muck storage, an slag outlet of the muck storage is connected to the primary slurry tank, the primary slurry tank is thoroughly connected to the secondary slurry tank, the secondary slurry tank has a bottom portion connecting to the primary slurry pump, the primary slurry pump has an inlet connecting to the secondary slurry tank and an outlet connecting to the primary hydrocyclone device, the primary hydrocyclone device has a slag outlet connecting to the secondary vibrating screen and a slurry outlet connecting to the secondary slurry tank and the slurry storage tank respectively, the secondary vibrating screen has a slag outlet corresponding to the muck storage and a slurry outlet connecting to the secondary slurry tank; the slurry storage tank has a bottom portion connecting to the secondary slurry pump, the secondary slurry pump has an inlet connecting to the slurry storage tank and an outlet connecting to the secondary hydrocyclone device, the secondary hydrocyclone device has a slag outlet connecting to the tertiary vibrating screen and a slurry outlet connecting to the slurry storage tank, the tertiary vibrating screen has a slag outlet corresponding to the muck storage and a slurry outlet corresponding to the slurry storage tank; the slurry input pipe is extended to the ground surface through the center pillar and connected to a slurry tank on the ground surface and has a bottom portion connecting to the slurry return pipe, while the slurry return pipe is connected to the slurry storage tank, the slurry return pipe has an outlet terminal arranged on a work surface of the cutter head; the slurry storage tank has a bottom portion connected to the transportation pump, the transportation pump is connected to the slurry output pipe, the slurry output pipe is connected to the pipe for slurry outflow installed on the center pillar and has an outlet arranged on the shaft opening and connected to external slurry treatment station; the muck storage has a bottom portion at which the rapid feeding device is arranged, the bucket and the cage are installed on the center pillar, the main hoist and the auxiliary hoist are installed on the upper portion of the derrick.
[0013] The support system for wall reinforcement comprises a module building system and an anchoring system, wherein the module building system comprises an auxiliary crane, a module board, a transportation concrete pipe, a buffer, a concrete mixing tank in shaft bottom, a concrete pump, a grouting pipe, and a concrete sealing ring, the anchoring system comprises a rig vehicle, a rig rail, a lifting cylinder, a multi-functional rig, a shotcreting manipulator and a material hoist; the auxiliary crane of the module building system is installed on a rear side of the device platform for inverted transportation of the module board, the entire module board and the concrete sealing ring forms a casting cavity, the buffer with multi-level is installed on the transportation concrete pipe, the transportation concrete pipe has a bottom end connected to concrete mixing tank, the concrete mixing tank has a bottom portion at which the concrete pump is installed, the concrete pump has an outlet connected to a grouting opening of the entire module board through the grouting pipe; the rig rail of the anchoring system is connected to the sliding ring through the lifting cylinder and has sliding connection with the guiding pillar, the rig vehicle is installed on the rig rail, the multi-functional rig is installed on the rig vehicle, the shotcreting manipulator is also installed on the rig rail, the material hoist is installed at a lower portion of the device platform which is position at a higher position function as an operation platform for steel binding.
[0014] The safety system comprises a sinking pump, a power and control module, a ventilation and water passage module, a stabilizer, a stabilizing vehicle for sinking pump, a flat car for shaft cover and a spare pillar, wherein the power control module comprises a main control room, an oil pump, an electrical cabinets, a transformer, an air compressor, a pumping station, a power cable, a communication cables and a cable reel, the ventilation and water passage module comprises a fan, an air duct formed from an inner side of the hollow portion of the center pillar and a clean water pipe, the sinking pump is hanged directly at a bottom portion of the machine through the stabilizing vehicle for sinking pump at the upper portion of the derrick, the sinking pump has a water inlet which penetrates through the retractable shield of the boring system to the slurry storage of the cutter head, the power and control modules are distributed and installed on different device platforms and the ground surface, the stabilizer is installed in the mounting base for stabilizer of the center pillar, the flat car for shaft cover is installed independently on an independent rail on the ground surface, the spare pillar is arranged on a side of the machine for backup.
[0015] The entire module board is formed by assembling a plurality groups of individual module board unit and is secured directly onto all sides of the wall of the shaft.
[0016] The support system for wall reinforcement further comprises an advanced grouting system and a concrete additives filling apparatus, the advanced grouting system is formed by the multi-functional rig and the grouting pump, the grouting pump is installed on the device platform at a rear position.
[0017] The advantageous effect of the present invention are:
[0018] 1. Structurally, the center pillar and full face vertical shaft drilling machine according to the present invention includes a center pillar, a device platform, a derrick, a boring system, a transportation system for people and materials, a support system for wall reinforcement, a safety system, and a control room, the machine utilizes a new method of shafting sinking and is mainly used for shaft sinking of different kinds of vertical shaft to achieve a full face and high efficient construction for vertical shaft drilling. The present invention is an integrated and complete equipment which integrated all functions of boring, tapping, support, drainage, ventilation, advanced detection together. Thus, parallel operation of shafting sinking, support and slag removal can be realized, high degree of automation and mechanization is achieved, while construction efficiency for vertical shaft drilling is increased and the construction cycle of shafting sinking and boring is shortened. The cost of shaft construction is dramatically lowered and the initial investment of mining site is lowered.
[0019] 2. Structurally, the center pillar of the present invention is formed by connecting a plurality segments of main body with hollow columnar structure. The center pillar has one end connected to the main driver and another end connecting to the sliding frame of the derrick located on the ground surface. The passage for slag removal, the secondary hoist rail, the cable, the compressed air pipe, the concrete pipe, the clean water pipe, the pipe for slurry outflow, the pipe for slurry inflow and the stabilizer are arranged in the peripheral edges of the center pillar and are passage through from the bottom of the shaft to the ground surface. The use of center pillar can eliminate the use of winch in traditional construction method. The equipment weight is supported by the center pillar. The gravitation force of the cutter head in the bottom of the shaft is controlled through the lifting cylinder located on the ground surface to control the propulsion force of the cutter head such that the propulsion equipment is simplified and the overall structure is simplified. The equipment and the different types of pipelines from the ground surface are attached to the center pillar such that the pipeline extension from the ground surface is achieved, thereby the pipelines extension is much more convenience, the pipelines in the bottom is avoided, and the slag removal of the main hoist is greatly increased. The lifting device employs rigid track element and is attached to the center pillar, which replaces the traditional guide rope design, that the rigid track element is much safer and the speed of lifting is much faster, thus the transportation speed of materials is much faster. The center pillar has a hollow construction and functions as an air dryer, that this internal fan design can quickly discharge the polluted gas from the bottom of the shaft to outside and ensure the air quality in the bottom of the shaft.
[0020] 3. Structurally, the retractable platform of the present invention includes a base platform, a small platform, a retractable cylinder and a seal member. The structure is simple, which can fulfill the requirement of passage of the module board, seal the gap in the shaft quickly, and prevent personal injury accidents caused by falling objects. The design is simple but reliable.
[0021] 4. Structurally, the boring system includes components such as a cutter head, a main driver, a retractable shield and a shield cylinder for full face vertical shaft drilling. The boring system also includes a cylinder for directional adjustment in which one end of the shaft of the cylinder is connected to the shield positioning ring through sliding engagement and the barrel is fixed connected to the main driver, thereby the position of the main driver is adjusted through the controlling the cylinder for directional adjustment, hence the adjustment of drilling direction is realized. The center pillar has one end installed onto the main driver and another end connected to the derrick on the ground surface, thus through the sliding frame of the derrick to control the applied pressure to the equipment, speedy excavation under different stratum conditions can be achieved and the operation is convenience.
[0022] 5. Structurally, the transportation system for people and materials according to the present invention includes a main hoist and an auxiliary hoist, a bucket, a cage, slurry pipes, slag pumps, arrangements for multi-level slurry treatment, and etc. to realize transportation of objects and materials such as personnel, slag and steel materials between the ground surface and the shaft. Personnel and material transportation between the shaft surface and the shaft bottom are realized by the auxiliary hoist. The slag transportation are divided into two parts. First, the slurry pump transports the slag carried by the slurry through the slurry outflow pipe to the slurry treatment devices, screening the large size sediments to the muck storage, then through the rapid feeding device positioned at the bottom portion of the muck storage to load the sediments into the bucket, and through the sliding groove member 309 of the derrick to load into the slag vehicle to transport to a predetermined location. The slurry is processed through multi-level screening and separation. Through treatment by the hydrocyclone devices, the slurry is transported to the slurry storage tank, then backflows to operation site through the slurry return pipe for recycling use. The highly concentrated slurry deposited on the bottom of the slurry storage tank is guided to flow to the transportation pump, the transportation pump is arranged to pump the highly concentrated slurry to flow through the slurry output pipe to the ground surface. The quality slurry from the ground surface is transported to the shaft bottom through the slurry input pipe. The above system works together to complete the transportation from the ground surface to the shaft bottom for personnel, materials, slag and slurry. The entire transportation system has an overall reasonable structural design. The transport of personnel, materials, slag and slurry can be operate at the same time. The equipment utility rate is increased and the work efficiency is increased.
[0023] 6. Structurally, the support system for wall reinforcement according to the present invention includes a module board, a transportation concrete pipe, a buffer, a piston pump, a grouting pump, a multi-functional rig, a shotcreting manipulator and etc. for the immediate support of the shaft wall. Furthermore, the rig vehicle can be used. The rig hydraulically controls the multi-functional rig for operation of anchoring, advanced detection and advanced grouting. Accordingly, the support system for wall reinforcement is capable of providing a number of operation platform for different tasks such as anchoring, casting and advanced grouting, that the support system provides reliable support while is capable of meeting the need of construction under different stratum conditions.
[0024] 7. Structurally, the safety system of the present invention comprises power arrangement, control arrangement, ventilation arrangement, water passage arrangement and etc. such that the need to safeguard the operation of equipment and the live of worker in the shaft is provide, and the normal operation of equipment and workers are ensured. The main hoist rail, the secondary hoist rail, the cable, the compressed air pipe, the concrete pipe, the clean water pipe, the pipe for slurry outflow, the pipe for slurry inflow and the stabilizer are all arranged on the center pillar and are extended downwardly together with the equipment. After the particular stroke of one center pillar and its pipelines is completed, the flat car is utilized to lock the flange of the center pillar, remove the connecting bolts, move the sliding frame at an upward position and disconnect the center pillar, then the spare pillar is lifted rapidly through the crane for pillar and the connection of the pillars are completed precisely through the control of the manipulator for pillar for the extension process of the center pillar without the need of pipe transportation to the bottom of the shaft. The process is fully mechanized, simple and convenience, fast and has low level of labor requirement, thus the equipment efficiency is increased.
[0025] 8. Structurally, according to the present invention, the entire module board employs groups of individual module board units which are constructed and casted together, thus continuous casting can be achieved. The concreting time of the wall is long, the module board can be dissembled and transported conveniently, and the efficiency and quality of the wall casting is increased.
[0026] 9. In additional, the center pillar and full face vertical shaft drilling machine according to the present invention is applicable to vertical shaft sinking for different constructions, which includes tunnel excavation, hydropower, nuclear power and underground engineering construction, that the underground construction channel can be open and fast and safe underground construction can be realized. The applicability is wide and is suitable for implementation promotion.
[0027] 10. Accordingly, the center pillar and full face vertical shaft drilling machine according to the present invention solves the construction problem of large-scale shaft sinking for coalmines, realizes the parallel operation for construction with automated, mechanized and integrated sets of equipment which includes serial functions of boring and propulsion, slag removal, support and protection, water passage and ventilation. The installation and disassembly process is convenience, the preparation time is saved, the construction efficiency is increased, the construction cost is lowered, and the construction safety is increased while the applicable area is wide. Therefore, very suitable for implementation promotion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The following is a brief description of the preferred embodiments of the present invention with accompanying drawings, wherein:
[0029] FIG. 1 is a schematic diagram of a center pillar and full face vertical shaft drilling machine according to a preferred embodiment of the present invention;
[0030] FIG. 2 a schematic diagram of a main body and its peripherals of a center pillar and full face vertical shaft drilling machine according to a preferred embodiment of the present invention;
[0031] FIG. 3 is a top view illustration of the schematic diagram of the main pillar and its peripherals of a center pillar and full face vertical shaft drilling machine according to a preferred embodiment of the present invention of FIG. 2 ;
[0032] FIG. 4 is a schematic diagram of a device platform of the center pillar and full face vertical shaft drilling machine according to the preferred embodiment of the present invention;
[0033] FIG. 5 is a schematic diagram of a derrick of the center pillar and full face vertical shaft drilling machine according to the preferred embodiment of the present invention;
[0034] FIG. 6 is a schematic diagram of a boring system of the center pillar and full face vertical shaft drilling machine according to the preferred embodiment of the present invention;
[0035] FIG. 7 is a schematic diagram of a transportation system for people and materials of the center pillar and full face vertical shaft drilling machine according to the preferred embodiment of the present invention;
[0036] FIG. 8 is a side view illustration of a schematic diagram of a transportation system for people and materials of the center pillar and full face vertical shaft drilling machine according to the preferred embodiment of the present invention;
[0037] FIG. 9 is a schematic diagram of a support system for wall reinforcement system of the center pillar and full face vertical shaft drilling machine according to the preferred embodiment of the present invention;
[0038] FIG. 10 is a schematic diagram of a safety system of the center pillar and full face vertical shaft drilling machine according to the preferred embodiment of the present invention;
[0039] The numerical references in the drawings:
[0040] 1 . Center pillar; 101 . Main pillar; 102 . Primary hoist rail; 103 secondary hoist rail; 104 . Cable; 105 . Compressed air pipe; 106 . Concrete pipe; 107 clean water pipe; 108 . Pipe for slurry outflow; 109 . Pipe for slurry inflow; 110 . Mounting base for stabilizer; 2 . Device platform; 201 . Fixed platform; 202 . Retractable platform; 202 - 1 . Base platform; 202 - 2 . Small platform; 202 - 3 . Retractable cylinder; 202 - 4 . Seal member; 3 . Derrick; 301 . Main body of derrick; 302 . Sliding frame; 303 . Pillar for sliding frame; 304 . Lifting cylinder; 305 . Movement arrangement; 306 . Crane for pillar; 307 . Manipulator for pillar; 308 . Power station; 309 . Muck chute; 4 . Boring system; 401 . Cutter head; 402 . Retractable shield; 403 . Shield positioning ring; 404 . Main driver; 405 . Operation station; 406 . Shield cylinder; 407 . Guiding pillar; 408 . Propulsion cylinder; 409 . Gripper sliding ring; 410 . Gripper; 411 . Gripper cylinder; 5 . Transportation system for people and materials; 501 . Slurry pump; 502 . Slurry inflow pipe; 503 . Slurry outflow pipe; 504 . Primary vibrating screen; 505 . Secondary vibrating screen; 506 . Tertiary vibrating screen; 507 . Primary hydrocyclone device; 508 . Secondary hydrocyclone device; 509 . Muck storage; 510 . Slurry storage tank; 511 . Rapid feeding device; 512 . Bucket; 513 . Main hoist; 514 . Auxiliary hoist; 515 . Slurry return pipe; 516 . Transportation pump; 517 . Slurry output pipe; 518 . Slurry input pipe; 519 . Primary slurry pump; 520 . Secondary slurry pump; 521 . Primary slurry tank; 525 . Secondary slurry tank; 523 . Cage; 6 . Support system for wall reinforcement; 601 . Auxiliary crane; 602 . Module board; 603 . Transportation concrete pipe; 604 . Buffer; 605 . Concrete mixing tank in the shaft bottom; 606 . Concrete pump; 607 . Grouting pipe; 608 . Concrete sealing ring; 609 . Rig vehicle; 610 . Rig rail; 611 . Lifting cylinder; 612 . multi-functional rig; 613 . Shotcreting manipulator; 614 . Material hoist; 615 . Grouting pump; 7 . Safety system; 701 . Sinking pump; 702 . Power control module; 703 . Ventilation and water passage module; 704 . Stabilizer; 705 . Stabilizing vehicle for sinking pump; 706 . Flat car for shaft cover; 707 . Spare pillar; 8 . Control room.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Embodiment 1
[0041] Referring to FIG. 1 of the drawings, a center pillar and full face vertical shaft drilling machine according to the preferred embodiment of the present invention is illustrated. The machine comprises a center pillar 1 , a device platform 2 , a derrick 3 , a boring system 4 , a transportation system for people and materials 5 , a support system for wall reinforcement 6 , a safety system 7 , and a control room 8 . Each system is constructed by independent equipment. The derrick is installed at a wellhead and the derrick comprises the control room. The center pillar is extended from a well bottom through the wellhead directly while connecting to a sliding frame of the derrick. The boring system is installed at a front end of the center pillar. A plurality of device platforms are installed on the center pillar sequentially from its rear end to its front end. The transportation system for people and materials and the safety system are installed on the device platforms located a rear end of the boring system respectively. The support system for wall reinforcement system is installed on the device platform located at the rear end of the boring system and the surrounding of the device platform.
[0042] Referring to FIGS. 2-3 of the drawings, the center pillar comprises a plurality segment of main body 101 having a hollow columnar structure which are connected through flanges and fastening members together to form the center pillar. A primary hoist rail 102 , a secondary hoist rail 103 , a cable 104 , a compressed air pipe 105 , a concrete pipe 106 , a clean water pipe 107 , a pipe for slurry outflow 108 , a pipe for slurry inflow 109 and a mounting base for stabilizer 110 are arranged along the peripheral edges of the main body of the center pillar.
[0043] Referring to FIG. 4 of the drawings, the device platform comprises a fixed platform 201 and a retractable platform 202 , wherein the retractable platform comprises a base platform 202 - 1 , a small platform 202 - 2 , a retractable cylinder 202 - 3 and a seal member 202 - 4 . The retractable platform 202 is installed on a module lining segment. The base platform 202 - 1 is fixedly connected to the center pillar 1 . The retractable cylinder 202 - 3 drives the small platform 202 - 2 to extend or retract. The seal member 202 - 4 prevents pieces of small material from falling through any gap of the platform.
[0044] Referring to FIG. 5 of the drawings, the derrick comprises a main body of derrick 301 , a sliding frame 302 , an pillar for sliding frame 303 , a lifting cylinder 304 , a movement arrangement 305 , a crane for pillar 306 , a manipulator for pillar 307 , a power station 308 , and a muck chute 309 . The main body of the derrick 301 has a lower portion through which the movement arrangement 305 is installed; and an upper portion on which the pillar for sliding frame 303 and the power station 308 are installed. The pillar for sliding frame 303 serves as a sliding rail for the sliding frame 302 . The lifting cylinder 304 has one end connected to the sliding frame 304 and another end connected to a bottom end of the pillar for sliding frame 303 . The crane for pillar 306 is installed at an upper portion of the main body of derrick 301 . The manipulator for pillar 307 and the muck chute 309 are installed in the lower portion of the derrick.
[0045] Referring to FIG. 6 of the drawings, the boring system for the vertical shaft drilling comprises a cutter head 401 , a retractable shield 402 , a shield positioning ring 409 , a main driver 404 , an operation station 405 , a shield cylinder 406 , a guiding pillar 407 , a propulsion cylinder 408 , a gripper sliding ring 409 , a gripper 410 and a gripper cylinder 411 . The cutter head 401 is driven by the main driver 404 to process excavation and rock breaking. A plurality of retractable shields 402 are arranged for forming a ring structure to act on the rock firmly through the shield cylinder 406 to produce friction such that anti-torque is provided to the machine. The guiding pillar 407 and the gripper sliding ring 409 are connected through sliding key connection, the gripper 410 is firmly gripped onto the wall surface through the gripper cylinder 411 to product friction such that the gripper 410 and the gripper sliding ring are secured, any rotational movement of the guiding pillar 407 is prevented, the propulsion direction of the machine is stabilized, accessory anti-torque to the retractable shield 402 is provided, and the propulsion cylinder 408 completes reciprocating movement during the excavating process of the gripper. The center pillar 1 is extended along the entire vertical shaft and connects to the main devices and the forward driving force and excavation speed of the machine is controlled through the lifting cylinder 304 of the derrick 3 . Control the retraction movement of the shield cylinder 406 and the gripper cylinder 411 to control the main driver 404 to having shifting movement such that the direction adjustment of the cutter head 401 is achieved, the operation station 405 is located at a lower position of the platform above the gripper, the operation and control is convenience and comfortable. The system design is simple, the control is reliable, is capable of providing sufficient driving force and torque for excavation at high speed and providing effective control on excavation direction such that the quality of shaft formation efficiency and construction is ensured.
[0046] Referring to FIGS. 7-8 of the drawings, the transportation system for people and materials 5 comprises a slurry pump 501 , a slurry inflow pipe 502 , a slurry outflow pipe 503 , a primary vibrating screen 504 , a secondary vibrating screen 505 , a tertiary vibrating screen 506 , a primary hydrocyclone device 507 , a secondary hydrocyclone device 508 , a muck storage 509 , a slurry storage tank 510 , a rapid feeding device 511 , a bucket 512 , a main hoist 513 , an auxiliary hoist 514 , a slurry return pipe 515 , a transportation pump 516 , a slurry output pipe 517 , a slurry input pipe 518 , a primary slurry pump 519 , a secondary slurry pump 520 , a primary slurry tank 521 , a secondary slurry tank 522 and a cage 523 . Personnel and materials such as steel are transported by auxiliary hoist 514 and the cage 523 for personnel and material transportation between the shaft surface and the shaft bottom. The slag transportation is divided into two parts, which are the dried residue and the fluidic slurry. The slag broken down by the cutter head 401 is carried by the slurry and is suck into the slurry inflow pipe 502 which is deeply inserted into the cutter head through the slurry pump 501 , the slurry is transported to the primary vibrating screen 504 through the slurry outflow pipe 503 to process separation by the primary vibrating screen 504 , some of the large size sediment enters into the muck storage 509 and the slurry after separation enters the primary slurry tank 521 , the primary slurry tank 521 and the secondary slurry tank 522 are inter-connected by interconnecting pipe, the slurry then enters into the secondary slurry tank 522 through the interconnecting pipe, the primary slurry pump 519 at the bottom of the secondary slurry tank 522 providing pumping action to transport the slurry to the primary hydrocyclone device 507 for separation process through action of the primary hydrocyclone device 507 , the slurry after separation process has further separation process through the secondary vibrating screen 505 , the dried sediment enters into the muck storage 509 and the slurry enters into the secondary slurry tank 522 for recycling treatment, the slurry after separation process of the primary hydrocyclone device 507 is transported to the slurry storage tank 510 or the secondary slurry tank 522 , the secondary slurry pump 520 at the bottom of the slurry storage tank 510 provides pumping action to transport the slurry to the secondary hydrocyclone device for separation process through action of the secondary hydrocyclone device 508 , then the slurry after separation process has further separation process through the tertiary vibrating screen 506 , the dried sediment enters into the muck storage 509 and the slurry enters into the slurry storage tank 510 , separation process of the slurry is then processed by the secondary hydrocyclone device 508 and the slurry is transported to the slurry storage tank 510 for storage and future use. The sediment stored inside the muck storage 509 is loaded into the bucket 512 rapidly through the rapid feeding device 511 positioned at a bottom portion and is transported outside the shaft through the main hoist 513 , then is loaded to a vehicle through the muck chute 309 to transport to a predetermined location. The slurry stored inside the slurry storage tank 510 is backflow to the slurry storage of the cutter head through the slurry return pipe 515 for another cycle. The highly concentrated slurry deposited on the bottom of the slurry storage tank 510 is flowing to the transportation pump 516 , passing to the slurry output pipe 517 and the pipe for slurry outflow 108 of the center pillar through the transportation pump 516 to reach a treatment station on the ground surface for arrangement of further processing. The high quality slurry required by the shaft body is transported to the slurry storage tank 510 directly through the slurry input pipe 518 and the pipe for slurry inflow 109 of the center pillar to meet the need of the construction inside the shaft body. The system utilizes the slurry to carry sediments and processes wet and dry separation of slurry and sediments. The people and objects has separate transportation arrangement. The realization of low power consumption and high efficiency slag removal is achieved. Each of the above systems can work together to provide transportation of people, materials, sediments and slurry between the well surface and the well bottom, therefore high efficiency transportation of materials and slag removal for the construction is ensured.
[0047] Referring to FIG. 9 of the drawings, the support system for wall reinforcement 6 comprises a module building system and an anchoring system. The module building system comprises an auxiliary crane 601 , a module board 602 , a transportation concrete pipe 603 , a buffer 604 , a concrete mixing tank 605 in shaft bottom, a concrete pump 606 , a grouting pipe 607 , and a concrete sealing ring 608 . The anchoring system comprises a rig vehicle 609 , a rig rail 610 , a lifting cylinder 611 , a multi-functional rig 612 , a shotcreting manipulator 613 and a material hoist 614 . The anchoring system further comprises an advanced grouting system and a concrete additives filling apparatus. The advanced grouting system comprises the multi-functional rig 612 and a grouting pump 615 . The auxiliary crane 601 of the module building system is installed on an upper portion of the device platform and is arranged for inverted transportation of the module board 602 . The entire module board 602 is constructed by a plurality groups of individual module board unit which are secured directly onto all sides of the wall. The steel mesh in the lower portion of the module board is constructed manually. The materials, such as steel and steel arch, which is required below the well surface, is transported to the lower portion of the machine through the auxiliary hoist 513 , and then is transported through the material hoist 614 to the construction site. After the manual binding of the steel is completed, the module board at the uppermost level is removed and is transported to a lower modeling location by the auxiliary crane 601 for module building, while the concrete sealing ring 608 is installed, then the grouting pipe 607 is connected to the grouting hole of the module board. Concrete is transported from the ground surface through the concrete pipe 106 of the center pillar, the transportation concrete pipe 603 and the buffer 604 to the concrete mixing tank 605 in the well bottom to process mixing so as to ensure the quality of the concrete. Then, the concrete pump 606 is used pumping the concrete to the inner portion of the module board through the grouting pipe 607 to complete the casting of wall for the shaft. The spray anchoring of the wall is mainly processed by using the multi-functional rig 612 and the shotcreting manipulator 613 . Both of them are installed onto the rig rail 610 through the rig vehicle 609 and are arranged for circular movement to complete the task of anchoring, slurry pouring and spraying around all sides of the wall. The lifting cylinder 611 can control the lifting movement of devices so as to meet the need at different height level. When the geological condition is unstable, the multi-functional rig 609 can adjust its angle to work with the grouting pump 615 to complete the grouting work in the front end and the peripheral of the machine, to reinforce the geological stability in advance and prevent the occurrence of any incidence.
[0048] Referring to FIG. 10 of the drawings, the safety system 7 comprises a sinking pump 701 , a power control module 702 , a ventilation and water passage module 703 , a stabilizer 704 , a stabilizing vehicle for sinking pump 705 , a flat car for shaft cover 706 and a spare pillar 707 . The power control module 702 comprises a main control room, an oil pump, an electrical cabinets, a transformer, an air compressor, a pumping station, a power cable, a communication cables and cable reel, which provides power source, system control, sealing and lubrication to all the devices of the machine. The ventilation and water passage module 703 comprises a fan, air duct formed inside the hollow portion of the center pillar and clean water pipe. The fan is installed at an inner side of the center pillar. The center pillar is function as an air dryer to blow the polluted air below the well surface to flowing outside the shaft rapidly, that this design is compact and has high air passage efficiency. The piping such as the water pipe and cable is directly installed around the center pillar and is extended together with the center pillar, that the piping extension is simple and fast. The sinking pump 701 is directly hanged at a bottom portion of the machine through the stabilizing vehicle for sinking pump 705 at an upper portion of the derrick. The sinking pump 701 has independent suspension system and transportation passage. The sinking pump 701 has a water inlet which penetrates through the retractable shield to the slurry storage of the cutter head and is arranged for emergent water discharge. The stabilizer 704 is installed in the mounting base for stabilizer of the center pillar, and is arranged for stabilizing the center pillar and the entire machine during the process of excavation. The flat car for shaft cover 706 is installed independently on a rail of the ground surface for closing the opening of the shaft, and is used to support the loading of different devices when the center pillar is extending, and processing piping extension by using the crane for pillar 306 to lift the spare pillar 707 .
[0049] The process of the present invention is as follows:
[0050] The main equipment is hanging onto the derrick 3 which is mounted on the ground surface through the center pillar 1 . Through the lifting cylinder 304 , the sliding frame 302 and the pillar for sliding frame 303 of the derrick, the upward and downward movement of the entire machine is controlled, and the lifting or forward excavation process of the equipment is realized. During excavation, the retractable shield 402 is firmly secured to the wall through gripping by the shield cylinder 406 to stabilize the cutter head 401 and provide anti-torque to other equipment. The gripper cylinder 411 provides gripping force to the gripper 410 to secure onto the wall, thus providing auxiliary anti-torque to the retractable shield to prevent rotational movement of equipment during the excavation process. The main driver 404 is started to drive the cutter head 401 to process excavation and rock breaking and the lifting cylinder 304 on the ground surface is used to control the applied pressure of the cutter head 401 to realize high efficient excavation process. The rock fragment resulted from cutting action of the cutter head 401 is carried by the high speed flowing slurry and is transported by the slurry pump 501 through pumping to the slurry treatment station. Through the primary vibrating screen, 504 , the secondary vibrating screen 505 , the tertiary vibrating screen 506 , the primary hydrocyclone device 507 and the secondary hydrocyclone device 508 , slag and slurry are separated and are arranged to store inside the muck storage 509 and the slurry storage tank 510 respectively. The slag inside the muck storage 509 is loaded into the bucket 512 rapidly through the rapid feeding device 511 at its bottom portion, transported outside to the ground surface through the main hoist 513 , and then loaded to a vehicle through the muck chute 309 to transport to a predetermined location. The slurry stored inside the slurry storage tank 510 is backflow to the cutter head through the slurry return pipe 515 for carrying out another cycle, thus a continuous slag removal process is achieved. The highly concentrated slurry deposited on the bottom of the slurry storage tank 510 is transported to the treatment station on the ground surface through the transportation pump 516 . The deterioration of slurry after a long period of usage in the shaft bottom will occur and require a replacement of new and quality slurry, which is transported through the pipe for slurry inflow 109 of the center pillar and the slurry input pipe 518 to the slurry storage tank. The slurry after deterioration is pumped out through the transportation pump 516 . Thus the replacement of slurry is completed to meet the construction need.
[0051] During the excavation process of the equipment, construction steps such as manual binding of steel, anchoring, spraying and casting steps are processed at the same time. The auxiliary hoist 514 is used to transport the materials required for wall support downward to the shaft. The material hoist 614 is used to distribute the materials to different construction sites. The multifunctional rig 612 is utilized for anchoring construction, manual binding is carried out for steel binding to construct the steel arch, then the shotcreting manipulator 613 is employed for carrying spraying for wall support such that incidences such as wall collapse is prevented. In the rear portion of the equipment, process secondary binding of steel and install the concrete sealing ring 608 , transport the module board 602 by utilizing the auxiliary crane 601 and process casting. Then, connect the grouting pipe 607 , transport concrete from the ground surface through the concrete pipe 106 , the transportation concrete pipe 603 and the buffer 604 to the concrete mixing tank 605 in the shaft. Thereafter, the concrete is pumped through the concrete pump 606 to transport to an inner portion of the module board to complete the wall casting process.
[0052] During the construction process, advanced geological survey is conducted by utilizing the multi-functional rig 612 . If special strata is encountered, the multi-functional rig 612 and the grouting pump 615 are used to carrying out grouting reinforcement for the sides of the wall and the front of the machine. The geological condition is improved and the construction safety is ensured.
[0053] As the equipment is processing excavation continuous at a downward direction, after the particular stroke of the lifting cylinder 304 , the center pillar 1 and the auxiliary pipelines is completed, an extension process of the center pillar is required. Utilize the flat car for shaft cover 706 to lock the flange of the center pillar, remove the connecting bolts, move the sliding frame 302 at a upward position, disconnect the center pillar 1 , hoist the spare pillar 707 rapidly through the crane for pillar 306 and utilize the manipulator for pillar 307 to precisely control and complete the docking of pillars. Thus, the extension of the center pillar 1 and other pipelines is processed. There is no need to transport the pipelines to the bottom of the shaft, the operation is convenience and highly efficient.
[0054] The center pillar and full face vertical shaft drilling machine according to the preferred embodiment of the present invention realizes the simultaneous operation of shaft drilling, support reinforcement and slag removal steps, thereby increasing the construction efficiency of shaft excavation, providing widespread applicability and construction safety. The construction time is shortened, the construction cost is lowered and has great significance for large-scale promotion.
[0055] One skilled in the art will understand that the embodiments of the present invention as shown in the drawings and described above are exemplary only and should not be limited as such. The embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. | A center-pillared full-face shaft drilling machine comprises a center pillar ( 1 ), device platforms ( 2 ), a derrick ( 3 ), a driving system ( 4 ), a personnel and material conveying system ( 5 ), a well wall support and protection system ( 6 ), a safeguard system ( 7 ), and an operation chamber ( 8 ). The derrick ( 3 ) is mounted at a wellhead. The operation chamber ( 8 ) is disposed on the derrick ( 3 ). The center pillar directly leads from the well bottom to the wellhead and is connected to a slide rack comprised in the derrick on the ground. The driving system ( 4 ) is mounted at the front end of the center pillar ( 1 ) of a device. The multiple device platforms ( 2 ) are sequentially mounted on the center pillar ( 1 ) of the device from rear to front. The personnel and material conveying system ( 5 ) and the safeguard system ( 7 ) are separately mounted on the device platforms at the rear of the driving system ( 4 ) and on the ground. The well wall support and protection system ( 6 ) is mounted on the device platforms at the rear of the driving system ( 4 ) and around the driving system ( 4 ). The shaft drilling machine solves the construction problem of large shafts in mines and the like, implements parallel construction operations of automated mechanical integrated complete devices having a series of functions such as shaft driving, residue discharging, support and protection, drainage and ventilation, facilitates dismounting and mounting of the device, saves preparation time, improves the construction efficiency, reduces construction cost, improves construction safety, and has a wide application range. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to improvements in a fluid coupling, and more particularly to a fluid coupling which is used as a component of a cooling fan system for an internal combustion engine of a vehicle.
2. Description of the Prior Art
JP-A-60-241534 discloses a typical fluid coupling which is operated to adequately rotate a cooling fan for cooling an internal combustion engine. A casing and a cover are fixedly connected with each other and define a sealed space therebetween. A cooling fan is installed to the outer peripheral portion of the casing and cover of the fluid coupling. The sealed space is divided into a storage chamber and a torque transmission chamber by a partition plate having a hydraulic flow control hole. The drive disc having a disc portion and a shaft portion is sealingly connected to the casing through a bearing so that the disc portion is rotatably disposed in the torque transmission chamber. A valve member is attached on the partition plate so as to close and open the hydraulic flow control hole in accordance with the change of ambient temperature. The torque transmission from the drive disc to the cooling fan is controlled in a manner to change the connecting area between the drive disc and the wall of the casing through operating fluid. Furthermore, a weight member is attached to the free end portion of the valve member to decrease the opening degree of the hydraulic flow control hole in accordance with the increase of the rotating speed of the cooling fan. A fluid damming space is defined by a peripheral portion of the drive disc and a part of a wall defining the sealed space. A return passage is formed to communicate the torque transmission chamber and the storage chamber to circulate the operating fluid. Thus, this conventional arrangement solves problems that the rotating speed of the cooling fan is radically changed at a generally predetermined temperature condition. That is, this conventional arrangement prevents the occurrence of a fan noise and a degradation of fuel consumption due to the hunting phenomenon.
However, this arrangement is required in production to correctly adjust the rigidity of the valve member and the weight of the weight member since the control of the rotating speed of the cooling fan is carried out by utilizing a centrifugal force applied to the valve member. Additionally, this adjusting operation is difficult to be correctly carried out, and a production cost becomes high due to the increase of parts and the like.
SUMMARY OF THE INVENTION
It is an object of the present invention to provides an improved fluid coupling for a cooling fan, which is free of the above mentioned drawbacks.
A fluid coupling for an engine cooling fan according to the present invention comprises a drive member to which a driven member are rotatably and sealingly connected. The driven member defines a storage chamber and an operation chamber thereinside and has a plurality of circular projections to an operation chamber defining surface thereof. The storage and operation chambers are communicated with a drain passage. A disc member is disposed in the operation chamber and fixedly connected to the drive member. The disc member has a plurality of circular projections which are arranged to be engaged with the plurality of circular projections of the driven member at a predetermined distance to form labyrinth grooves therebetween. A passage is defined on the driven member so as to radially extend relative to the center axis of the driven member.
With this arrangement, a major part of the operating fluid is supplied to a diametrically outer side of the labyrinth grooves, and the degree of the energy transmission is smoothly changed in accordance with the amount of the operating fluid filled in the labyrinth grooves.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings, like reference numerals designate like parts and elements throughout all figures, in which:
FIG. 1 is a side cross-sectional view of a first embodiment of a fluid coupling according to the present invention;
FIG. 2 is a plan view of a cover member of FIG. 1;
FIG. 3 is a plan view which shows an installation condition of a valve plate to a partition plate;
FIG. 4 is a graph which shows an output characteristics of the fluid coupling according to the present invention; and
FIG. 5 is a side cross-sectional view of a second embodiment of a fluid coupling according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIGS. 1 to 3, there is shown a first embodiment of a fluid coupling F for a cooling fan of an internal combustion engine in accordance with the present invention.
As shown in FIG. 1, the fluid coupling F comprises a drive shaft 1 which is provided with a V-belt pulley 2. A housing 3, to which a cooling fan (though not shown) is secured, is rotatably supported to the drive shaft 1 through a bearing 4. The housing 3 includes a body member 7 fixedly engaged with the outer peripheral portion of the bearing 4 and a cover member 9 secured to the body member 7 with bolts 8. The body member 7 and the cover member 9 define a space thereinside. The space is divided into a storage chamber 11 and an operation chamber 12 by a partition plate 10. A disc member 6 is fixedly connected to a top end portion of the drive shaft 1 and disposed in the operation chamber 12. The disc member 6 has a plurality of circular projections 13 which protrude toward the cover member 9. The disc member 6 and the housing 3 are coaxially arranged relative to a center axis X of the drive shaft 1 as shown in FIG. 1. The circular projections 13 are engaged at a predetermined distance with a plurality of circular projections 14 of the cover member 9 so as to form labyrinth grooves therebetween. Operating fluid such as silicon oil is stored in the storage and operation chambers 11 and 12. The labyrinth grooves are arranged to act as a fluid coupling due to the viscous resistance of the operating fluid.
On the other hand, the cover member 9 has a drain passage 15 which communicates the storage chamber 11 and the operation chamber 12. A projection 17 is formed at an outer peripheral portion of the cover member 9 so as to be high at the portion marked by diagonally hatched lines between steps 17a and 17b, and to be low in the other portion, as shown in FIG. 2. With this arrangement, when the fluid coupling F is rotated, the projection 17 performs as a pump for supplying a fluid from the operation chamber 12 to the storage chamber 11 through the passage 17.
The partition plate 10 is provided with a through-hole 18 which communicates the storage chamber 11 and the operation chamber 12. A rotating shaft 20 is sealingly and rotatably engaged in a through-hole (no numeral) formed at a center portion of the cover member 9. The inner end (positioned in the storage chamber 11) of the rotating shaft 20 is fixedly connected with a valve plate 21 which is fittingly and slidably contacted with the partition plate 10. The other end of the rotating shaft 20 is fixedly connected with the central end portion of a bimetal 19 of a spiral shape. The other end of the bimetal 19 is fixed to the cover member 9. Accordingly, the rotating shaft 20 is rotated in accordance with the deformation of the bimetal 19 due to the change of air temperature at the rearward portion of a radiator (not shown). In accordance with the rotating speed of the rotating shaft 20, the through-hole 18 is opened and closed.
FIG. 3 shows the cover member 9 which is in a condition that the partition plate 10 is detached. The cover member 9 has four passages 25 which outwardly extends and perpendicularly crosses the circular projections 14 of the cover member 9. The four passages 25 are arranged at 90° intervals on the cover member 9 to cut away a part of the circular projections 14 so that the bottom surface of the passage 25 is the same in hight level as the bottom surface of the cover member 9. In FIG. 2, reference numeral 26 designates a shelf portion to which a partition plate 10 is disposed and whose projection is caulked to fixedly connect the partition plate 10 with the cover member 9.
The manner of operation of the thus arranged fluid coupling F will be discussed hereinafter.
Just after starting of the engine, the valve plate 21 closes a through-hole 18 due to the operation of the bimetal 19 and practically stops the circulation of the operating fluid when the ambient temperature near the bimetal 19 is low. Accordingly, the flow amount of the operating fluid supplied to the labyrinth grooves is largely decreased. This tends to lower the transmitted torque from the disc member 6 to the housing 3, and therefore the cooling fan is rotated in a low rotating speed.
Then, in accordance with the raising of the ambient temperature near the bimetal 9, the valve plate 21 gradually opens the through-hole 18 so that the operating fluid in the storage chamber 11 is fed into the operating chamber 12.
Almost all the amount of the operating fluid, which is sucked into the operation chamber 12 through the through-hole 18, is guided to the pump (mechanism) portion 16 formed at the outer peripheral portion of the disc member 6 through the passage 25 without passing through the labyrinth grooves. Although a part of the operating fluid is returned to the storage chamber 11 through the return passage 15 due to the pump portion 16, almost amount of the operating fluid fills the labyrinth grooves from the outer peripheral portion of these grooves. Accordingly, the housing 3 connected with the cooling fan increases its rotating speed in accordance with the amount of the operating fluid filled in the labyrinth grooves.
With this improved arrangement, the operating fluid supplied from the storage chamber 11 to the operation chamber 12 is supplied to the labyrinth grooves from its outer peripheral portion without being supplied from its inner peripheral portion, and the amount of the operating fluid filled in the labyrinth grooves is increased in accordance with the amount of the operating fluid supplied through the through-hole 18. Therefore, the cooling fan is smoothly rotated in the transition process from a low ambient temperature condition to a high ambient temperature condition without occurring an unnecessary drive torque in the labyrinth grooves.
Accordingly, the output power characteristics of the cooling fan (fluid coupling) in accordance with the raising of the ambient temperature is changed without occurring a hunting phenomenon, in cooperation with the shapes of the through-hole 18 and the valve sheet 21, as shown in FIG. 4,
Referring to FIG. 5, there is shown a second embodiment of the fluid coupling F in accordance with the present invention.
The second embodiment of the fluid coupling F is similar to the first embodiment except that a ring member 30 is secured to the inner side of (most inner one) of the circular projections 14. The ring member 30 is formed so that its inner diameter portion approaches to the disc member 6. That is, the ring member 30 is bent at its middle circular portion so as to be separated from the through-hole 18.
With this arrangement, the operating fluid supplied to the operating chamber 12 through the through-hole 18 is guided to the pump portion 16 through the passage 25 since the ring member 30 functions as a fence against the operating fluid. Accordingly, the labyrinth grooves is more effectively filled with the operating fluid from the outer peripheral portion of the grooves.
Since the passage 25 is formed at the cover member 9 to extend outwardly in the above discussed embodiments, the operating fluid tends to be guided into the passage 25 along an inner wall surface of the operating chamber 12 of the cover member 9 when the operating fluid is fed from the through-hole 18 to the operation chamber 12. This arrangement is preferred to forming a passage to the disc member 6. | A fluid coupling of a cooling fan is for an internal combustion engine in an automotive vehicle and comprises labyrinth grooves defined by circular projections formed on a drive disc and a driven member, respectively. Rotating energy transmission from the engine to the cooling fan is carried out through the labyrinth grooves at which rotating energy is transmitted through an operating fluid. A plurality of passages are radially formed on the driven member to smoothly change the transmission ratio of the rotating energy by supplying the operating fluid to the outside portion of the labyrinth grooves. | 5 |
FIELD OF THE INVENTION
[0001] The invention relates to the manufacture of flexible packaging by the welding of plastic films. More specifically, the invention relates to the production of flexible tubes intended for storing and delivering liquid or pasty products.
PRIOR ART
[0002] Flexible tubes consisting of a head and a flexible skirt obtained by welding a web called a “laminate”, the laminate being formed from several plastic or metal layers, are known. These skirts are obtained by unwinding a web, by forming the web into a tubular body, by welding the ends of the web together, generally forming a slight overlap, and finally by cutting the tubular body into segments of identical length. A tube head is then welded or moulded onto the end of said skirt. The tube head includes a neck with an orifice and a shoulder that joins the neck to said skirt. The tube is thus delivered to the filler, head down and with the delivery orifice closed off (for example by a screwed cap) so as to be filled via that end of the tube which has remained open. Once the tube has been filled, said end is closed by pinching and welding the film to itself.
[0003] One difficulty encountered when producing flexible tubes by welding lies in the deformation of the skirt during the welding operation. Often the skirts produced do not have a perfectly circular geometry, as is desirable, but instead a cross section in the form of a “pear” or of a “water drop”. These out-of-roundness defects are particularly prejudicial to the joining and tube-filing operations. The operation of joining the skirt to the head by welding requires the head to be inserted into the skirt, which operation is all the more difficult the greater the out-of-roundness defect. During filling, the filler must introduce a nozzle via that end of the tube which has remained open. This operation is greatly disturbed when the cross section of the tube is not circular.
[0004] The out-of-roundness of the skirts has an influence on the final geometry of the tube and in many cases the out-of-roundness defects impair the aesthetic properties of the packaging. For this reason, it is desirable to have perfectly circular skirts.
[0005] Patent Application WO 2004/039561 proposes to deform the laminate beyond the elastic limit prior to the welding operation. A first method proposed in Application WO 2004/039561 consists in thinning the web by about 1% by calendering. A force of between 2.5 and 500 newtons per millimetre width of the web must be applied. When the web comprises more than 70% plastic by volume, it is suggested heating said web before calendering to a temperature between 75 and 120° C. A second method proposed in Application WO 2004/039561 consists in carrying out an embossing operation, resulting in the creation of raised features and of hollows, the amplitude of which is preferably between 1/15 and 3 times the thickness of the web. This calendering or embossing operation should have the effect of modifying the residual stresses in the laminate. According to the inventors, this method makes the elastic behaviour of the web uniform and in the case of embossing it is possible to increase the strength of the web in the longitudinal direction and in the cross direction. However, the method proposed in Patent Application WO 2004/039561 has several drawbacks. It cannot easily be used with printed webs and in particular when the printing is on the surface. This is because the calendering or embossing operation tends to damage the printing owing to the deformation, temperature and friction generated by the method.
[0006] Another method for improving the roundness of the tubes is proposed in Swiss Patent Application CH 695 937 A5. This method consists in carrying out a heat treatment on the tubular body before it is cut into segments of identical length. The tubular body is produced according to the prior art, the welding method comprising in particular: a shaping step, in which the web is wound around a welding rod in order to form a cylindrical body; a heating step in order to melt the ends of the web to be welded together; a step of pressing the ends to be welded together; and a step of cooling the welded zone. Application CH 695 937 A1 then proposes to carry out a heat treatment on the tubular body before it is cut into segments of identical length. The heat treatment consists in making the temperature of the tubular body uniform by means of a fluid in contact with the outer surface of the tube. The device serving to carry out the heat treatment is inserted between the welding device and the cutting device. One drawback of the method proposed in Application CH 695 937 A5 is due to the time needed to carry out an effective heat treatment. This time is longer the greater the thickness of the laminate, so that the proposed method proves to be unsuitable for thick laminates and for high production rates.
GENERAL DESCRIPTION OF THE INVENTION
[0007] The invention consists of a welding method for producing tubular bodies of improved roundness by welding a laminate. This welding method is characterized in that the welded zone undergoes a deformation so as to increase its area.
[0008] The welding method according to the invention comprises the following steps:
a laminate is shaped around a welding rod ; the ends of the laminate to be welded together are heated; said ends are pressed together; the welded zone is deformed so as to increase its area; and the welded zone is cooled.
[0014] In the description of the invention, the expression “welded zone” represents that part of the laminate which is heated, compressed and cooled in the welding method. The welded zone is not limited to that part of the laminate forming the welded overlap, rather it constitutes that part of the laminate which is thermally affected by the welding operation.
[0015] The term “laminate” is understood to mean a sheet formed from several plastic or metal layers, which is obtained by lamination.
[0016] The term “deformation” is understood to mean a modification of the shape of the welded zone, causing the area of the welded zone to be increased.
[0017] Advantageously, between the step of pressing the ends together and the step of deforming the welded zone, the ends are cooled, without however reaching the ambient temperature.
[0018] According to a preferred embodiment, the welded zone is elongated in the longitudinal direction, i.e. in a direction parallel to the axis of the tube.
[0019] According to a second embodiment, the welded zone is elongated transversely, i.e. in a direction perpendicular to the axis of the tube.
[0020] A third embodiment consists in combining the longitudinal and transverse elongations of the welded zone.
[0021] The deformation of the welded zone compensates for the shrinkage of said zone and relaxes the stresses associated with said shrinkage. The tubes obtained have a high roundness.
[0022] The operation of elongating the welded zone takes place after the ends to be welded together have been heated and before the tube is cooled to the ambient temperature. Preferably, the deformation operation takes place before the tubular body is cut into segments of identical length.
[0023] Advantageously, the deformation operation consists in increasing the area of the welded zone by an amount corresponding to the shrinkage of said zone due to the effect of the heating and cooling. This amount depends on the properties of the laminate and in particular of the constituent films of said laminate. For a laminate shrinking substantially in the longitudinal direction, the deformation of the welded zone may be as much as 1 to 2%.
[0024] Preferably, the welding method consists in tempering the entire tubular body.
[0025] Advantageously, the tubular body is tempered as a temperature between 50 and 95° C. during the deformation of the welded zone.
[0026] A variant of the invention consists of a post-treatment of the welded tube, said post-treatment comprising at least one operation of elongating the welded zone.
[0027] The invention will be better understood from the following figures:
[0028] FIG. 1 illustrates a tubular body obtained by welding a thermoplastic laminate, the cross section of which has out-of-roundness defects.
[0029] FIG. 2 illustrates a device for elongating the welded zone in the longitudinal direction.
[0030] FIG. 3 illustrates a device for elongating the welded zone in the transverse direction.
[0031] FIG. 4 illustrates the cross section of the tube obtained by applying the method described in the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0032] FIG. 1 illustrates the cross section of a tubular body having out-of-roundness defects which the invention is able to remedy. The cross-sectional defects result from the production of the tubular body by welding using the methodes known in the prior art and without operations, prior to or after the welding method, as described in Patents WO 2004/039561 and CH 695 937 A5. The tubular body 1 results from the welding of a laminate 2 , the welded ends of which form an overlap in the welded zone 3 . Out-of-roundness defects 4 and 5 are observed close to the welded zone 3 and overall affect the roundness of the tubular body. The invention also makes it possible to improve the roundness of a tubular body formed by butt-welding the ends of a laminate together.
[0033] It is observed that the out-of-roundness defects 4 and 5 appear during the welding method and in particular while the welded zone is being cooled. It is also observed that the welding defects appear during cooling and are associated with the thermal shrinkage of the welded zone, said shrinkage having the effect of generating stresses and of deforming the circular cross section.
[0034] The invention consists of a welding method that makes it possible to compensate for the shrinkage of the welded zone and thus to prevent the generation of stresses which deform the tubular body. To do this, the welding method comprises, in addition to the standard heating, compression and cooling operations, an operation of elongating the welded zone. The elongation of the welded zone is advantageously carried out during cooling, when the welded zone is strong enough to be elongated, but before the welded zone is completely cooled. The stretching operation consists in elongating the welded zone by an amount corresponding to the shrinkage of said zone under the effect of the heating and cooling. This amount depends on the properties of the laminate and in particular of the constituent films of said laminate. For a laminate shrinking substantially in the longitudinal direction, the elongation of the welded zone may be as much as 1 to 2%.
[0035] In addition to the operation of elongating the welded zone, it is advantageous to reduce the temperature difference between the welded zone and the rest of the tubular body. It has been found that by reducing this temperature difference it is possible to delay the appearance of stresses associated with the shrinkage of the welded zone and thus to delay the operation of elongating the welded zone. It is favourable to elongate the welded zone when the temperature of said zone is close to the temperature of the rest of the tubular body. In the production of PE (polyethylene) tubular bodies, this temperature is between 50 and 95° C. and preferably between 60 and 80° C.
[0036] The operation of elongating the welded zone takes place after the ends to be welded together have been heated, but before the tube is cooled to the ambient temperature. Advantageously, the stretching operation is performed before the tubular body is cut into segments of identical length. In a continuous welding method, starting from a laminate wound in the form of a reel, the invention consists: in unwinding the laminate; in shaping the laminate around a welding rod;
[0037] in heating the ends of the laminate which are intended to be welded together; in compressing the ends to be welded together against each other; in at least partly cooling the welded zone; in elongating the welded zone; and in cutting up the tubular body into cylindrical skirts intended to be joined to heads. The laminate is tempered during the welding operation so as to reduce the thermal gradient between the welded zone and the laminate forming the non-welded part of the tubular body. The laminate may be easily heated by means of the welding rod around which the laminate is shaped. Another method for tempering the laminate consists in using hot air, which is blown onto the external or internal surface of the laminate. For laminates that include an aluminium foil, the laminate may be heated by inducing currents in the aluminium foil.
[0038] The first embodiment of the invention consists of a welding method that includes an operation of elongating the welded zone in the longitudinal direction, i.e. in a direction perpendicular to the cross section of said tubular body. A first example for elongating the welded zone in a method in which the laminate moves at a constant speed over a welding rod, consists in varying the speed of the welding zone. This speed variation is obtained for example by means of a device made up of drive rollers located in the welding zone, the rotation speed differential of which has the effect of elongating the welded zone. A second example of the method and device for elongating the welded zone in the longitudinal direction is illustrated in FIG. 2 . This device, inserted into a welding rod, is illustrated in a cross-sectional view of the welding rod 6 , said cross-sectional view being parallel to the axis of the rod. This device is formed from a set of rollers 7 external to the rod and of rollers 8 housed in the rod which act together to elongate the welded zone 3 . Only the welded zone 3 is elongated—the laminate 2 forming the tubular body is not deformed. The elongation of the welded zone 3 is adjusted by the pressure exerted by the rollers 7 , said pressure having the effect of modifying the path of the welded zone 3 . The number and diameter of the rollers 7 and 8 are adjusted according to the laminate and according to the welding speed. The width of the rollers 7 and 8 is adjusted according to the width of the welded zone.
[0039] A second embodiment of the invention consists of a welding method that includes an operation of elongating the welded zone in the transverse direction, i.e. in a direction perpendicular to the axis of the tube. An example of a device for elongating the welded zone in the transverse direction is illustrated in FIG. 3 . This device, inserted into a welding rod, is illustrated in a cross-sectional view of the welding rod 6 , said cross section being perpendicular to the axis of the rod. This device is formed from a set of rollers 7 external to the rod and of rollers 8 housed in the rod which act together to elongate the welded zone 3 . Only the welded zone 3 is elongated, the laminate 2 forming the tubular body not being deformed. The elongation of the welded zone 3 is adjusted via the pressure exerted by the rollers 7 , said pressure having the effect of transversely elongating the welded zone 3 . The number and diameter of the rollers 7 and 8 are adjusted according to the laminate and according to the welding speed. The width of the rollers 7 and 8 is adjusted according to the width of the welded zone,
[0040] A third embodiment of the invention consists in elongating the welded zone 3 longitudinally and transversely. The third embodiment may be implemented by the sequential use of the devices illustrated in FIGS. 3 and 4 . A device enabling simultaneous longitudinal and transverse elongation may also be used.
[0041] The first, second and third embodiments of the invention make it possible to compensate for the shrinkage of the welded zone during cooling and to prevent the shrinkage stresses that deform the tubular body. After elongation, the tubular body, the temperature of which is preferably uniform over its entire circumference, is cooled to the ambient temperature uniformly. This results in a tubular body having no out-of-roundness defect. The cross section of this tubular body is illustrated in FIG. 5 , in which the out-of-roundness defects close to the welding zone 3 have been eliminated.
[0042] In a manufacturing method in which the laminate is not moving during the welding operation, many devices applying tension to the welded zone may be used to create the deformation. These devices consist in blocking one end of the welded zone and in pulling on the other end. Most of the tensioning principles and mechanisms can be adapted so as to carry out this operation.
[0043] Within the context of the invention, it is generally preferable to deform only the welded zone, in particular when the laminate is printed, since the operation of deforming the laminate in its entirety may have the effect of damaging the printing. However, in certain cases the tube may be elongated in its entirety.
[0044] A variant of the invention consists of a post-treatment of the welded tube, said post-treatment comprising at least one operation of elongating the welded zone. The post-treatment operation consists: in heating the tubular body uniformly to a temperature between 60 and 95° C.; in elongating the welded zone; in shaping the tubular body; and in cooling the tubular body. The elongation of the welded zone may be longitudinal and/or transverse. The shaping operation consist in giving the tubular body a circular cross section, it being possible for the shaping operation to be carried out by applying an internal pressure, by applying an external vacuum or by use of a mandrel.
[0045] The roundness of the tubular body obtained according to the method described in the invention is improved, as shown in FIG. 4 . This tubular body 1 is formed from a laminate 2 , the ends of which have been welded together. The invention applies to the lap welding or to the butt welding of the ends. | The invention relates to a method of welding a laminate for the production of flexible tubular plastic bodies, which method comprises the following operations:
a laminate is shaped around a welding rod; the ends of the laminate to be welded are heated; said ends are pressed together and at least partly cooled; the welded zone is deformed so as to increase its area; and the welded zone is cooled.
The invention also relates to a device suitable for using the aforementioned method. | 1 |
PRIORITY
This application claims priority under 35 U.S.C. §119 to an application filed in the Korean Intellectual Property Office on Dec. 29, 2005 and assigned Serial No. 2005-132859, the contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a Broadband Wireless Access (BWA) communication system, and in particular, to an apparatus and method for adaptively changing a pilot pattern according to a link in an Orthogonal Frequency Division Multiplexing (OFDM) communication system.
2. Description of the Related Art
Although there are many wireless communication technologies proposed as candidates for high-speed mobile communications, OFDM is considered the most prominent future-generation wireless communication technology. It is expected that OFDM will be adopted for most wireless communication applications by the year 2010. OFDM has been adopted as a standard for an Institute of Electrical and Electronics Engineers (IEEE) 802.16 Wireless Metropolitan Area Network (WMAN) categorized into the 3.5 th Generation (3.5G) technology.
In a conventional OFDM communication system, a transmitter simultaneously sends pilot subcarrier signals to a receiver with transmission of data subcarrier signals. The receiver performs synchronization acquisition, channel estimation, and Base Station (BS) identification using the pilot subcarrier signals. A transmission rule for sending the pilot subcarrier signals is known as “pilot pattern”.
The pilot pattern is determined in consideration of coherence bandwidth and coherence time. The coherence bandwidth is the maximum bandwidth over which a channel is relatively constant or non-distorting in the frequency domain, and the coherence time is the maximum time for which the channel is relatively constant in the time domain. Since the channel can be assumed to be constant over the coherence bandwidth for the coherence time, one pilot signal suffices for synchronization acquisition, channel estimation and BS identification.
Conventionally, a fixed pilot pattern is used and existing adaptive pilot pattern techniques focus on optimization of pilot power and throughput. A technique for adaptively changing a pilot pattern according to a link status (e.g. coherence bandwidth and coherence time) is yet to be developed.
Radio channels are said to be a wide range of random channels and it is difficult to always ensure optimum performance over these random channels with the conventional fixed pilot pattern. Assuming that a pilot pattern is created using the same number of pilots, a layout of pilot subcarriers affects performance according to the link status, which in turn directly influences channel estimation performance. That is, the channel estimation performance may increase according to the pilot pattern. Since the channel estimation performance has an influence on Bit Error Rate (BER), it is important to select a pilot pattern that minimizes channel estimation errors.
SUMMARY OF THE INVENTION
An object of the present invention is to substantially solve at least the above problems and/or disadvantages and to provide at least the advantages below. Accordingly, an object of the present invention is to provide an apparatus and method for adaptively changing a pilot pattern according to a link in a BWA communication system.
An object of the present invention is to provide an apparatus and method for selecting a pilot pattern that minimizes channel estimation errors in a BWA communication system.
A further object of the present invention is to provide an apparatus and method for adaptively changing an uplink pilot pattern according to an uplink in a BWA communication system.
Another object of the present invention is to provide an apparatus and method for selecting a pilot pattern based on the Mean Square Error (MSE) of frequency-domain data in a BWA communication system.
According to the present invention, in an apparatus for determining a pilot pattern in a BWA communication system, an OFDM demodulator generates frequency-domain data by fast-Fourier-transform (FFT)-processing a received signal. A pilot pattern decider calculates a coherence bandwidth and a coherence time using subcarrier values received from the OFDM demodulator, and selects one of a plurality of pilot patterns according to the ratio of the coherence bandwidth to the coherence time.
According to the present invention, in a method of determining a pilot pattern in a BWA communication system, subcarrier values are generated by FFT-processing a received signal. A coherence bandwidth and a coherence time are calculated using the subcarrier values. One of a plurality of pilot patterns is selected according to the ratio of the coherence bandwidth to the coherence time.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which:
FIG. 1 is a block diagram of a transmitter in a BWA communication system according to the present invention;
FIG. 2 is a block diagram of a receiver in the BWA communication system according to the present invention;
FIG. 3 is a detailed block diagram of a pilot pattern decider illustrated in FIG. 2 ;
FIG. 4 is a flowchart illustrating an operation for feeding back a pilot pattern in the receiver in the BWA communication system according to the present invention;
FIG. 5 is a graph illustrating a first embodiment of a pilot pattern selection method according to the present invention;
FIG. 6 is a graph illustrating a second embodiment of a pilot pattern selection method according to the present invention; and
FIG. 7 is a graph comparing the present invention using an adaptive pilot pattern with a conventional technology using a fixed pilot pattern in terms of performance.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the present invention will be described herein below with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail for the sake of clarity and conciseness.
FIG. 1 is a block diagram of a transmitter in a BWA communication system according to present invention. The transmitter is a relative concept, in that it is a Mobile Station (MS) on the uplink and a BS on the downlink.
Referring to FIG. 1 , the transmitter includes a pilot pattern generator 100 , an encoder 102 , a modulator 104 , a data mapper 106 , a frame buffer 108 , an OFDM modulator 110 , a Digital-to-Analog Converter (DAC) 112 and a Radio Frequency (RF) processor 114 .
In operation, the encoder 102 encodes an input information bit stream at a coding rate and outputs the resulting coded bits or code symbols. With the number of the information bits being denoted by k and the coding rate being denoted by R, the number of the code symbols is k/R. The encoder 102 may be a convolutional encoder, a turbo encoder or a Low Density Parity Check (LDPC) encoder.
The modulator 104 generates complex symbols by mapping the coded symbols to signal points according to a modulation scheme or modulation level. For example, the modulation scheme is one of Binary Phase Shift Keying (BPSK), Quadrature Phase Shift Keying (QPSK), 8-ary Phase Shift Keying (8PSK), 16-ary Quadrature Amplitude Modulation (16QAM) and 64QAM. One bit (s=1) is mapped to one signal point (i.e. complex symbol) in BPSK, two bits (s=2) are mapped to one signal point in QPSK, three bits (s=3) are mapped to one signal point in 8PSK, four bits (s=4) are mapped to one signal point in 16QAM and six bits (s=6) are mapped to one signal point in 64QAM.
The data mapper 106 maps the complex symbols to subcarriers according to a control signal received from a higher layer and provides the mapped complex symbols to memory addresses in the frame buffer 108 of an actual frame size.
The pilot pattern generator 100 selects a pilot pattern according to feedback information (i.e. pilot pattern selection information) received from a receiver and outputs pilot symbols to corresponding addresses of the frame buffer 108 according to the selected pilot pattern. For example, if a frame size is 64×64 and one frame delivers 64 pilot symbols, a 16×4 first pilot pattern and a 4×16 pilot pattern are available. According to the first pilot pattern, the pilot symbols are mapped equidistantly at an interval of 16 on the frequency axis and at an interval of 4 on the time axis. The second pilot pattern indicates that the pilot symbols are mapped equidistantly at an interval of 4 on the frequency axis and at an interval of 16 on the time axis. The first pilot pattern is viable when a coherence bandwidth is greater than a coherence time, while the second pilot pattern is used when the coherence time is greater than the coherence bandwidth.
The frame buffer 108 is a buffer for ordering the complex symbols in an actual transmission order, prior to input to the OFDM modulator 110 . The frame buffer 108 sequentially outputs the buffered complex symbols based on timing synchronization on an OFDM symbol basis.
The OFDM modulator 110 converts the complex symbols received from the frame buffer 107 to time-domain sample data by Inverse-Fast-Fourier-Transform (IFFT)-processing the complex symbols, and adds a copy of a last part of the sample data to the sample data, thereby generating an OFDM symbol.
The DAC 112 converts the sample data to an analog signal. The RF processor 114 , including a filter and a front-end unit, processes the analog signal to an RF signal and ends the RF signal on a radio channel through a transmit antenna. The transmitted signal experiences a multi-path channel, is added with noise, and then arrives at a receive antenna of the receiver.
FIG. 2 is a block diagram of a receiver in the BWA communication system according to the present invention. The receiver is a relative concept, in that the BS is the receiver on the uplink and the MS is the receiver on the downlink.
Referring to FIG. 2 , the receiver includes a pilot pattern decider 200 , an RF processor 202 , an Analog-to-Digital Converter (ADC) 204 , an OFDM demodulator 206 , a subcarrier demapper 208 , an equalizer 210 , a demodulator 212 , a decoder 214 and a channel estimator 216 .
In operation, the RF processor 202 , including a front-end unit and a filter, downconverts an RF signal received on a radio channel to a baseband signal. The ADC 204 converts the analog baseband signal received form the RF processor 202 to a digital signal.
The OFDM demodulator 206 removes a Cyclic Prefix (CP) from the digital data and generates frequency-domain data by FFT-processing the CP-removed data.
The subcarrier demapper 208 extracts data symbols from the OFDM-demodulated data received from the OFDM demodulator 206 and outputs the data symbols to the equalizer 210 . It also extracts pilot symbols at pilot subcarrier positions and provides the extracted pilot symbols to the channel estimator 216 .
The channel estimator 216 performs channel estimation using the pilot symbols. The equalizer 210 channel-compensates the received data symbols based on channel estimate values received from the channel estimator 216 , that is, compensates for noise created on the radio channel.
The demodulator 212 demodulates the symbols received form the equalizer in accordance with the modulation scheme used in the transmitter and outputs the resulting coded data. The decoder 214 decodes the coded data corresponding to the coding method used in the transmitter, thereby recovering the original information data.
The pilot pattern decider 200 calculates the mean square error (MSE) of each of the channel-compensated subcarrier values received from the equalizer 210 and calculates a coherence bandwidth and a coherence time by accumulating the MSEs on the frequency and time axes. The pilot pattern decider 200 selects a pilot pattern by comparing the ratio of the coherence bandwidth to the coherence time with a threshold value and generates feedback information indicating the selected pilot pattern. The feedback information is sent to the transmitter on a feedback channel.
If the coherence bandwidth is greater than the coherence time, a pilot pattern is selected which maps pilot symbols densely along the time axis. If the coherence time is greater than the coherence bandwidth, a pilot pattern is selected which maps pilot symbols densely along the frequency axis.
FIG. 3 is a detailed block diagram of the pilot pattern decider 200 illustrated in FIG. 2 .
Referring to FIG. 3 , the pilot pattern decider 200 includes a frame buffer 300 , a mean square error (MSE) calculator 302 , a frequency-axis accumulator 304 , a time-axis accumulator 306 , a first arranger 308 , a second arranger 310 , a first selector 312 , a second selector 314 , a first adder 316 , a second adder 318 , a ratio calculator 320 and a pilot pattern selector 322 .
In operation, the frame buffer 300 buffers the frequency-domain frame data received form the equalizer 210 . A 64×64 frame size (40964 subcarrier values) is assumed. The MSE calculator 302 calculates the MSEs of the subcarrier values (received complex symbols) received from the frame buffer 300 . The MSEs can be calculated in any one of known methods and a description of the MSE calculation will not be provided herein.
The frequency-axis accumulator 304 accumulates the calculated 64×64 MSE values along the frequency axis or column by column, thereby creating 64 accumulation values. The time-axis accumulator 306 accumulates the calculated 64×64 MSE values along the time axis or row by row, thereby creating 64 accumulation values.
The first arranger 308 orders the 64 accumulation values received from the frequency-axis accumulator 304 in a descending order, and the second arranger 310 orders the 64 accumulation values received from the time-axis accumulator 306 in a descending order.
The first selector 312 selects a number of (e.g. 32) accumulation values among the ordered accumulation values from the first arranger, starting from the highest accumulation value, and the second selector 314 selects a number of (e.g. 32) accumulation values among the ordered accumulation values from the second arranger 310 , starting from the highest accumulation value.
The first adder 316 generates a value C b indicating the coherence bandwidth by summing the accumulation values received the first selector 312 , and the second adder 318 generates a value C t indicating the coherence time by summing the accumulation values received from the second selector 314 .
The ratio calculator 320 calculates the ratio R of the coherence bandwidth to the coherence time by dividing C b by C t and then calculating the Log 10 of the division result.
The pilot pattern selector 322 compares the ratio R with a threshold value, selects a pilot pattern based on the comparison adaptively according to the link, and generates feedback information indicating the selected pilot pattern.
The ratio R may be inaccurate when too a small number of MSEs are in an entire frame. In this case, the sum of C b and C t is compared with a threshold value. If the sum is less than the threshold value, a pilot pattern is selected based on the average of previous C b to C t ratio.
FIG. 4 is a flowchart illustrating an operation for feeding back a pilot pattern in the receiver in the BWA communication system according to the present invention.
Referring to FIG. 4 , the receiver downconverts an RF signal received through an antenna to a baseband signal and OFDM-demodulates the baseband signal, thus acquiring frequency-domain data in step 401 .
In step 403 , the receiver extracts symbols at subcarrier positions (i.e. pilot symbols) from the frequency-domain data and performs channel estimation using the extracted symbols.
The receiver channel-compensates the frequency-domain data using channel estimate values in step 405 and calculates the MSEs of the channel-compensated subcarrier values (complex symbols) in step 407 .
In step 409 , the receiver accumulates the MSE values along the frequency axis, selects a number of accumulation values in a descending order, and sums them. The sum is the coherence bandwidth C b . In step 411 , the receiver accumulates the MSE values along the time axis, selects a number of accumulation values in a descending order, and sums them. The sum is the coherence time C t .
The receiver calculates the ratio R of the coherence bandwidth to the coherence time by dividing C b by C t and calculating the Log 10 of the division result in step 413 .
In step 415 , the receiver compares the ratio R with 1. If R is less than 1, which implies that the coherence bandwidth is greater than the coherence time, the receiver selects a first pilot pattern in which pilot symbols are mapped more densely along the time axis in step 417 .
If R is equal to or greater than 1, which implies that the coherence time is greater than the coherence bandwidth, the receiver selects a second pilot pattern in which pilot symbols are mapped more densely along the frequency axis in step 419 .
After selecting the pilot pattern, the receiver generates feedback information indicating the selected pilot pattern and sends the feedback information on the feedback channel to the transmitter in step 421 .
FIG. 5 is a graph illustrating a first embodiment of a pilot pattern selection method according to the present invention. A 64×64 frame size and mapping of 64 pilot symbols per frame are assumed.
Referring to FIG. 5 , a pilot pattern is selected in which the ratio R (C b /C t ) converges to 1. If the coherence bandwidth is greater than the coherence time, the 16×4 first pilot pattern is selected in which pilot symbols are mapped at an interval of 16 along the frequency axis and at an interval of 4 along the time axis. If the coherence time is greater than the coherence bandwidth, the 4×16 second pilot pattern is selected in which pilot symbols are mapped at an interval of 4 along the frequency axis and at an interval of 16 along the time axis. In this manner, although the same number of pilot symbols are allocated to each frame, the layout of the pilot symbols is adapted to the link status.
FIG. 6 is a graph illustrating a second embodiment of a pilot pattern selection method according to the present invention.
Referring to FIG. 6 , two thresholds are set for pilot pattern switching. If the ratio R (C b /C t ) is greater than a first threshold, the 16×4 first pilot pattern is selected. If the ratio R is between the first and second thresholds, an 8×8 third pilot pattern is selected in which pilot symbols are mapped at an interval of 8 along the frequency axis and at an interval of 8 along the time axis. If the ratio R is less than the second threshold, the 4×16 second pilot pattern is selected. This pilot pattern selection method leads to robust operation against factors such as sudden channel changes or frame delay by use of a smooth transitional pattern. Preferably, the first and second thresholds are empirically obtained.
A simulation was performed to verify the performance of the present invention, under the following parameters listed in Table 1.
TABLE 1
Carrier frequency
5 GHz
FFT size
1024 (16 users)
Bandwidth
40 MHz
Symbol length
25.6 μs
Guard interval
3.2 μs (T/8)
Max delay spread
5 ns, 10 ns
Mobile velocity
5 km/h, 160 km/h
Modulation
QPSK
Channel estimator
Bilinear interpolation
Pilot patterns used
3 (4 × 16, 8 × 8, 16 × 4)
Pilot density
<2%
User frame size
64 × 64
Channels
AWGN, 3-ray indoor
FIG. 7 is a graph comparing the present invention using an adaptive pilot pattern with a conventional technology using a fixed pilot pattern in terms of performance.
Referring to FIG. 7 , the horizontal axis represents received signal strength (E b /N o ) and the vertical axis represents Bit Error Rate (BER). As noted from the graph, the adaptive pilot pattern method of the present invention outperforms the conventional fixed pilot pattern method.
As described above, the present invention advantageously reduces channel estimation errors by adaptively mapping the same number of pilot symbols in a different layout according to the link status. The minimization of channel estimation errors leads to the increase of data BER. Also, the present invention reduces signaling overhead by switching a pilot pattern on a frame-by-frame basis.
While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. | An apparatus and method for determining a pilot pattern in a Broadband Wireless Access (BWA) communication system are provided. In the pilot pattern determining method, an Orthogonal Frequency Division Multiplexing (OFDM) demodulator generates frequency-domain data by fast-Fourier-transform (FFT)-processing a received signal. A pilot pattern decider calculates a coherence bandwidth and a coherence time using subcarrier values received from the OFDM demodulator, and selects one of a plurality of pilot patterns according to the ratio of the coherence bandwidth to the coherence time. | 7 |
BACKGROUND OF THE INVENTION
Solar cells and photovoltaic (PV) panels, have evolved from bulky inefficient cells to light weight, thin, highly effective producers of electricity from sunlight. Similarly, light emitting diodes (LED's) have become light weight, small and efficient users of electricity to produce light.
This invention combines photovoltaic panels and electrically produced light, such that the light is integrated into the interior of the electrically producing photovoltaic materials. This integration consists of holes in the electric producing photovoltaic materials which facilitate display of the electrically produced light. This light may be produced by electrical, or chemical reactions similar to light emitting diodes, electroluminescent materials, a phosphorescent substance, chemiluminescent technology, excitation of inert gas in neon lighting, and fluorescent lighting.
In prior art devices holes were provided in solar cells in order to increase the production of electricity, by increasing surface area due to holes, or by channeling various photovoltaic materials from various layers into adjacent layers to produce a more efficient solar cell. Note for example U.S. Pat. No. 4,795,500 and 5,468,988.
Additionally, holes have been placed in PV materials to allow day-lighting through the cells, for use of the natural light inside buildings or cars as in U.S. pat. No. 5,254,179.
Also it is known to combine photovoltaic materials, batteries and electronic circuits to produce display devices. Note for example U.S. Pat. No. 4,006,583, 4,759,735 and 5,523,776.
BRIEF SUMMARY OF THE INVENTION
The invention is produced by including a hole, or holes, directly in the photovoltaic material for mounting a light. In a first embodiment light from a point source, such as a light emitting diode, is allowed to pass through the holes from the dark side of the photovoltaic, or PV panel, which may comprise a single PV cell or a number of cells, to produce a display on the light receiving side of the PV panel, or in a second alternative embodiment light emitting diodes or some other display means are placed directly into this hole or holes to project out on the front face of the PV panel. The PV material is not adversely affected by any shadows onto the PV material and the holes do not result in a significant loss of power output.
This design produces a product that is lower in cost than if the lighting was packaged outside the PV cells. Panels produced in accordance to this invention are portable and can be flexible. By combining the PV cells and the display, the whole system costs are reduced in comparison with a PV cell, with having a separate display system. The size, weight, and expense are reduced, while the portability, efficiency and reliability are increased.
Using the PV panel as the light supporting structure enables the units to be sealed and compact. Such sealed units are more reliable and can be made resistant to mishap or vandalism. The specific use of the PV material, integrated with the display, will also reduce theft because the perforated panels are easily identified and do not appear to be as desirable for other uses.
It should be noted that putting a hole in the cell typically does not hurt the cells, except that the area taken up by the cell can no longer produce electricity from light energy.
Some PV materials need to have the holes placed in cells in a special process, for instance, amorphous cells should not have a hole punched from the front to the back, rather, it is better to place the hole from the back to the front to prevent shorting out the material.
This design optimize a small amount of holes to produce a utility lighting function. Holes are integrated into the PV materials so as to not adversely effect the operation of the light to electrical energy conversion process of the PV materials.
Panels according to this invention may be activated by darkness and motion detection to turn on a highly visible LED for lighting a path at night.
Alternatively the panel could turn on an infrared LED thus illuminating an area for infrared television monitors without letting an intruder know that he has been detected. Such a device would be useful in battle situation or about protected compounds. The light could flash on and off, in a code such that the pattern would give information regarding the motion that was detected and when it was detected.
Panels according to the invention can be used as a sign displaying information or warning drivers about road conditions. One example of such a sign is a flashing arrow of LED lights, used for directing drivers away from a stalled vehicle. In this case a sign can be rotated to direct traffic to the right or left about the stalled vehicle. When the panel is carried on the shelf by the rear window of a car, ambient light would maintain the battery at full charge, ready to use during a breakdown for directing traffic away from a broken down car.
An EXIT sign is another application of this design, with the letters E-X-I-T, spelled out with LED lights integrated into a PV material. Such a panel could have a means of sensing the light levels in a location, if the ambient lighting levels are lowered, indicating a potential emergency situations, the sign would turn on, and flash. This would eliminate the need for electrical lines for the sign installation, thus making the installation much less expensive. Such signs would be particularly useful for temporary buildings such as tents used for circuses or for selling merchandise. This sign could be designed to provide either a constant illumination, or flashing illumination.
Property and house street numbering is facilitated by this design, because it is frequently necessary to place such signs where they are visible from the street, and often this location may be a long distance from any electrical outlet. In the daytime, batteries would be charged by the PV cells, at night the numbers would be illuminated showing the address of the property. It should be noted here that large PV cells are preferred because holes for forming the outline of letters or numbers can be punched almost anywhere in the interior of a cell with out seriously affecting the operation of that cell.
Other applications include attracting attention to billboard signs. In this case the sign itself would be a PV panel provided with the display. The message could be integrated into the configuration of the sign with LED lights.
Signs according to this invention could be activated by temperature to produce a message like "FREEZING CONDITIONS", or signs can be activated by moisture sensors to indicate "SLIPPERY WHEN WET" condition. Signs can be turned on by various light levels, or by darkness. Signs can be turned on in response to the detection in motion.
Alternatively remotely located signs can include a computer chip which will receive and display any number of messages responsive to a signal from a communication device.
It is an object of this invention to create a unit that produces its own power from ambient light energy.
It is a further object to produce a display device which is compact, inexpensive, vandal resistant and extremely reliable, which then lights electrically efficient bulbs.
It is a further object to produce a panel that need not be optimally oriented to collect solar energy, but combines the ability to display lighting efficiently, when and where it is needed. In doing so, it eliminates the requirement of optimally orientation relative to the sun.
It is a further object to produce a display device which includes an electrical storage unit such as a battery to produce electricity and light when the ambient light energy is not available.
Alternatively it is an object of the invention to provide a solar electric system sized to directly power electrical lights of a display utilizing only ambient light and thus operate without an electrical storage unit.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
FIG. 1 shows a section of first embodiment of the invention taken along line 1--1 of FIG. 4.
FIG. 2 shows a block diagram of the various components of the display and PV system.
FIG. 3 shows a second embodiment where a display light passes through a hole in the PV panel.
FIG. 4 shows the front face of a sign in accordance with the preferred embodiment.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1 and 4 show a first preferred embodiment of the invention comprising an emergency blinker to be carried in a car and designed for use during emergencies to direct traffic around a stalled or disabled vehicle or an object in the roadway.
As shown in the FIG. 4, the emergency blinker comprises a PV panel 17 having six cells 16. Each cell 16 has a nearly invisible grid of vertical and horizontal conductors 13, 14 embedded therein and electrical connectors 15 which may connect the cells in series or parallel. The panel further includes apertures 6 positioned in three rows 10, 11, 12 forming arrows pointing to the right. When providing apertures in a photovoltaic panel it is important to carefully position each aperture so that it does not cut any of the grid wires 13, 14 but an almost infinite number of shapes and patterns are still possible with only negligible loss to the electric generating capacity of the panel. In operation these rows would light in sequential order 10, 11, 12, 10, 11, . . . to clearly give oncoming traffic the idea that it should move to the right about the object.
FIG. 1 is a diagrammatic view taken along line 1--1 in FIG. 4 showing a single LED light 3 provided behind each of the aperture 6. A timing circuit shown in block diagram in FIG. 2 sequentially lights the rows of lights to direct traffic right around a stalled vehicle or object in the road. The PV cells forming the front face of the display panel extend both above and bellow the Led lights forming arrows 10, 11, 12. As seen in the drawing, the PV panel 1 has a front surface 9 to be exposed to ambient light and a back surface 8 to which lights 3 are mounted. In this embodiment the PV panel is provided with transparent or translucent coatings 2 and 7 which cover the front and rear surfaces of the panels and may fill openings 6. Light 5 emitted by the LED is clearly visible to oncoming traffic thought the aperture 6.
In FIG. 4 I have shown a series of PV cells forming a panel having a series of apertures. Alternatively it should be noted that this could be a single cell forming the entire PV panel.
Each PV cell used in the display panel is relatively large preferably extending the height of the panel so that electrical connections between adjacent cells are above or below the display. This means that there is no danger that the holes forming the display will inadvertently puncture the electrical connection between adjacent cells, but it is also possible to provide apertures in a grid of PV cells which extends both vertically and horizontally.
In place of the arrows shown in FIG. 4 any indicia is possible. House numbers, warning signs, Exit signs or multi color animated displays are only a few of the possibilities.
I have shown multiple openings forming a coherent display, but the scope of the invention should not be limited there to. It is also contemplated that a number of panels could be provided each having only a single opening and a highly visible single light. These panels would be provided along a path or trail to illuminate the way for foot traffic in areas where no electricity exists. In order to conserve energy the Condition Sensor of FIG. 2 could be activated by the conditions of darkness and sensed movement only.
Alternatively, each panel could be provided with one or more infra-red lights and the motion detectors could be placed in such a way as to detect movement into a restricted area such as a battle field. The infra red light would alert snipers or watchers with infra-red scopes with out alerting the intruder to the fact that his intrusion has been detected.
In prior art devices the display panel and the solar collecting panel were provided on separate panels. This permitted the display panel to be oriented at the best viewing angle while the solar panel was oriented at the best light collecting angle relative to ambient light. The prior art configuration increase the cost of the device and increase by many fold the possibility to being damaged because of the external wire connecting the panels. Also, the fact that there are external wires makes it difficult to provide a sealed unit.
Combining the PV and display panels means that the light collector must be positioned for optimal viewing rather than for optimal light collection consequently there must be greater emphasis on conserving electrical energy. The unitary nature of the instant device makes that unit so inexpensive that it can be afforded by anyone who can afford an automobile and so reliable that it could be used under water or at least in a heavy rain storm with out danger of malfunction. The device of the instant invention can be stored on the shelf near the back window of a car and the ambient light will be more than enough to maintain an internal battery pack in fully charged condition.
It is also contemplated that the On/Off/Auto switch could be replaced by a receiver for receiving signals similar to those transmitted for a pager, and the flasher display circuit would respond to the received signal by displaying one of several messages stored in a memory register. Such a device could be used to change the speed limit along a highway in order to allow for changing weather conditions.
Another strategy for conserving energy would be to flash the sign and to increase the length of time between flashes as the battery becomes weakened.
If it were desirable to have a panel which was lit only during the day the electrical storage, the On/Off/Auto switch and the condition sensor could be eliminated and the PV panel could operate the lights directly.
For most situations LED's are preferred because of their efficiency and brightness, but for a panels to be used as an air rescue device a strobe light would produce enough light to be seen by passing airplanes. Other alternatives include electroluminescent lighting, phosphorescent substance, chemiluminescent technology, neon lighting, fluorescent lighting, infra-red light or incandescent light.
In FIG. 2 I have shown an On/Off/Auto switch for use in the flasher of FIG. 4. In the "off" position the solar panel would charge or maintain the battery pack but the lights would never come on. In the "on" position the lights would be on while the solar panel simultaneously charges the battery. In the "auto" position the battery would be charged as usual but the lights would be controlled and turned on only when the proper conditions are sensed. For example darkness and/or time combined with motion detection could be used to turn on the lights only after dark and only when a car is approaching. This latter setting could be used when it is necessary to abandon a vehicle over night and it is feared that the battery might not last till morning light for recharging.
By adding a temperature sensing means to the circuit of FIG. 2 one could illuminate a sign which says "WARNING ICE CONDITIONS". With this sort of controller the device could be set to operate only when the light level and temperature sensors determine that there is likely to be ice and the timer can be used to see that the device only operates at night and is not affected by oncoming headlights. A motion detector would cause the device to operate only when an approaching car is detected.
A second preferred embodiment is shown in FIG. 3. This embodiment is similar to that of FIG. 1 in that it again includes a PV panel 1 having a front surface 9 back surface 8 with transparent or translucent coatings 2 and 7. In the FIG. 3 embodiment openings 6 in the PV panel are not filled or covered by the coatings. Instead the front end 4 of the LED 3 projects through the PV panel 1 to emit its light 5 on the front face of the panel.
Typically, PV cells and panels are encapsulated in glass 2, to keep weather effects away from the cells. Holes can be place in the encapsulant, the lights placed into the holes and the encapsulant and lights can then be sealed or re-encapsulated to form an integral sealed unit.
For the sake of simplicity no attempt has been made to show specific wire diagrams of circuits needed to carry out the invention. It is understood that such circuits are known and easy to design. The examples given above as modifications to the block diagram of FIG. 2 are just that "examples". Numerous other uses will occur to those skilled in the art of designing signs for roads and pathways. | A display device comprising a photovoltaic (PV) panel adapted to simultaneously produce electrically needed to operate a display and form either the background or foreground of the said display. The PV panel comprises large continuous sheets of PV material provided with one or more openings. Either light for the display or the display mechanism itself pass through the openings in PV material. The device may include a computer or electrical circuit which will activate the display device responsive to temperature, moisture, light conditions or to a remote signal such as a pager. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an obstacle protection arrangement comprising a deformable spatial structure wherein a dissipation of energy is brought about during a deformation resulting from a collision with a moving object (a road vehicle), which arrangement is composed of a series of segments which are interconnected--in the anticipated direction of motion--and which are each comprised of at least one gate-shaped support member standing on the ground and positioned transversely to said direction, as well as of a box-like structure fastened thereto and internally provided with deformation elements, a flank member being affixed on both sides of each segment.
2. Description of the Prior Art
A specific embodiment of such an arrangement is known from U.S. Pat. Nos. 3,982,734 and 3,944,187. The main purpose is to protect solitary obstacles by roadsides in such a manner that vehicles that have moved off the roadway are prevented from coming into contact with such obstacles. It occurs not infrequently that such solitary obstacles are located in the pointed area of road exits or in the continuous shoulder along the roadway.
The protection of an obstacle may be achieved in two ways. In the event of a collision occurring on the nose portion of the obstacle protector means, the vehicle is to be stopped prior to touching the obstacle to be protected. If a collision occurs with the flank of the obstacle protector means, the travelling direction of the vehicle must be changed so as to guide it past the obstacle. In both such cases the occupants of the vehicle should not be exposed to intolerably high decelerations.
In practice obstacle protectors are known to exist which offer none or unsuitable flank protection. Also, several types of obstacle protection arrangements often require an elaborate foundation and anchoring. In addition, various types of known obstacle protectors either do not correctly function in an optimum fashion in the event of a head-on collision when its parallel structure is altered into a V-shape, for example, when placed in a gore area.
SUMMARY OF THE INVENTION
The object of the invention is to provide an improved arrangement which can be used in a V-form for a pointed area at an exit, but also in a parallel form in the shoulder along the roadway. In addition, it is an object of the invention to provide an arrangement which is adaptable to the local conditions and which affords easy mounting and whose cost is relatively low. These and other objects are attained according to the invention by using an obstacle protector means which--as viewed in the intended direction of traffic motion--has its rear support member fastened to a foundation, the front support member being located in a horizontal guideway allowing displacement in the direction of motion only, whilst the segments are rigidly coupled to one another, so that the whole arrangement behaves like a rigid girder.
These features lead to a construction of an obstacle protector means which affords a high degree of rigidity against bending both in a horizontal and in a vertical plane so that two points of foundation are sufficient. The obstacle protector means is composed of a number of standard units or segments, which makes it possible to adapt the obstacle protector to the local situation in terms of absorbing capacity. The degree of energy absorption may be adapted to the local conditions as anticipated by varying, in addition to having the choice of number of segments, the dimensions and compositions of the material of the deformation elements disposed within the box-like structure, as well. In this manner it is possible to assemble successive types of obstacle protectors as a function of the mass and speed of the passing vehicles. Due to the construction with segments, a damaged obstacle protector means according to the invention has a decided residual value, since the parts that have been slightly damaged or have remained undamaged can be used again. The V-shaped embodiment as used in a pointed area may, in the presence of a guide rail construction, be linked up thereto via one or both of the flank members.
In the event of a collision with the nose portion, the segments are successively compressed, starting with the nose segment. Such compression of segments is possible because the flank members when being displaced can pass one another and the box-like structure can be compressed. The deformation of the box-like structure in particular provides the greatest absorption of the kinetic energy of the vehicle.
A most efficient solution for providing for an appropriate energy-absorbing capacity of the box-like structure is obtained by providing the box-like structure with crumpling or ripple tubes which absorb the major portion of the energy in a collision. If needs be, it is possible to increase the deformation resistance of the successive segments--as viewed in the direction of motion--by using more ripple tubes.
In order that the ripple tubes may function without disturbances occurring, the top and bottom side of the box-like structure are beaded a little outwardly, at least one rod being disposed between these expanded areas. This form of construction is also favorable when transporting the individual box-like structures, and prevents damage due to vandalism. According to a particular embodiment, each segment is provided with flank members provided with longitudinal undulations engaging one another. Such members extend on both extremities past the respective segment so that there is an overlapping with neighboring flank members, in which case the connection of the adjoining segments is also carried through by means of at least one double-angled strip forming a connection with the support member. The strip affords a change in the mutual position on the one hand, but no substantial change in the angle of the flank extremities since an extra flange part forms a guide when the flank members are sliding past each other. This is important because upon impact, the divergence of the flank member should not result in the occurrence of laterally directed spearheads formed by the extremities of the flank members.
The features of the present invention which are believed to be novel are set forth with particularity in the appended claims.
Other claims and many of the attendant advantages will be more readily appreciated as the same becomes better understood by reference to the following detailed description and considered in connection with the accompanying drawings in which like reference symbols designate like parts throughout the figures.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of a diverging obstacle protector means to be used for the protection of an obstacle in a pointed area;
FIG. 2 is a side view of the arrangement according to FIG. 1;
FIG. 3 is a top view similar to FIG. 1 of an obstacle protector means having a parallel form as is to be used for the shoulder along the roadway;
FIG. 4 is a side view of the arrangement according to FIG. 3;
FIG. 5 is a top view of an alternative form of the arrangement shown in FIGS. 1 and 2;
FIG. 6 shows, on an enlarged scale, a detail of the arrangement as per FIG. 1;
FIG. 7 is a sectional view taken along line VII--VII in FIG. 6;
FIGS. 8a and 8b provide a perspective view and a front view, respectively, of a nose segment of the obstacle protector means according to the invention;
FIG. 9 is a perspective view of the box-like structure of FIG. 6 with edge faces being partially cut out,
FIGS. 10-12 show the double-angled strip of the obstacle protector means of the invention;
FIGS. 13 and 14 illustrate two situations arising in the event of a collision;
FIG. 15 shows a construction enabling the absorption of occurrent tensile forces into a flank member of the alternative form of the embodiment as per FIG. 5;
FIGS. 16a, 16b, 16c provide three views of a nose segment; and
FIGS. 17a and 17b show the results of an eccentric impact upon the nose segment.
DESCRIPTION OF PREFERRED EMBODIMENTS
As can be seen best in the FIGS. 1, 2 and 3, the obstacle protector means is comprised of a series of interconnected segments A provided with a nose segment A'. Each segment is composed of a U-shaped support member G disposed transversely to the direction of motion X and provided for fastening an internal box-like structure N thereto. The support members G are slidably or rollably supported on the ground, such as by rollers R, with the exception of the rearmost segment which is attached to a fixed foundation L. Also, tie members V which are to absorb the longitudinal forces occurring in the associated guide rail construction are attached to the foundation L. The nose segment A' is provided with a guide member H, as shown in FIG. 2, which prevents displacement in any direction other than the direction of travel X (see FIGS. 8a and b).
Each segment is provided on both sides with a flank member C which is connected to the associated support member G via an angled strip D. The shape and function of these strips D are illustrated in FIGS. 10-12. On the bending lines of the strip it is possible to provide weakened sections, for instance bore holes. These strips afford a shifting of successive flank members C past one another during a collision. The support members G move along thus causing a certain degree of transversely directed deflection to occur so that no wedging action takes place. The flank members C will not diverge sidewardly, which is also in the interest of preventing damage to vehicles of third parties or injury to the latter.
FIG. 9 clearly shows that each box-like structure N is provided with crumpling or ripple tubes B. The purpose of these tubes is to absorb the major portion of the kinetic energy of the colliding vehicle. In addition, the box-like structure N imparts stability to the entire structure, specifically, at the occurence of lateral forces (see FIGS. 13 and 14). The box-like structure N facilitates transport and assembly of the obstacle protector means.
The construction of the nose segment A' is best apparent from the FIGS. 8a, 8b, 16a, 16b and 16c. There is an arcuate nose apron C' which may be regarded as a complement to the flank members C ending in each segment A. A support member G' cooperates on its lower side with a foundation guide member H. Inside the nose apron C' there are provided several straight thin plates U (see FIGS. 16a, 16b and 16c). This enables the nose segment at the beginning of the collision to adopt the shape and/or deformation of the vehicle in a manner so that the deformative force of the nose segment is lower than the threshold value of the ripple tubes. This causes the deforming of the first box-like structure to be introduced in a proper manner (FIGS. 17a and 17b).
The functioning of the obstacle protector means is dependent upon the manner in which the collision with the structure proceeds. In a collision a distinction may be made between a head-on collision and a lateral collision. A head-on collision may be still further differentiated into a centric, an eccentric and an angular collision. In the event of a centric collision, first the nose apron C' of the structure will deform. Thereupon, the support member G' will start sliding freely with its feet in the foundation guide member H, and the two flank members C will be pushed backwards. Simultaneously, the first box-like structure will be compressed. The subsequent segments A will be compressed in succession. The number thereof depends upon the magnitude of the quantity of kinetic energy to be dissipated.
The deceleration of the vehicle is determined by:
(a) the ripple resistance of the ripple tubes;
(b) the acceleration of masses (segments A and A' and flank members C);
(c) several other resistance factors such as:
the deforming resistance of the nose segment A',
the mutual friction of the flank members C,
the rolling and sliding resistance of the support members G and
the resistance factors of the vehicle itself.
Due to the influence of the mass inertia and occurent frictions in the structure, the segments will deform one by one. The plates P 1 and P 2 of the box-like structure N are so designed during a head-on collision the upper plate P 1 can freely bend upwards and the lower plate P 2 can freely bend downwards (see FIG. 9). Such upward and downward bending quality is important so as to prevent the tubes from being struck by the lower plate P 2 or upper plate P 1 during impact. In order to ensure this shape, the box N is internally provided with spacer means S. The lower and upper plates P 2 and P 1 , respectively, can absorb tensile forces in the event of a lateral collision. The spacer means S are also advantageous in preventing damage due to vandalism committed by passersby climbing upon the obstacle protector means. The ripple tubes B in the box N are centered and fixedly secured on the frontal face of the box N by means of spiders M. On the back side they are confined in apertures 20 provided in the back plate Q of the box N. By premounting the ripple tubes B, errors are avoided when assembling the structure.
The support members G FIGS. 1 and 3 are so designed as to afford easy and safe mounting of the boxes N through bolt holes 21 on the upper and lower sides, see FIG. 9. The wheels R on the legs of the support members G ensure a smooth displacement of the support members in the longitudinal direction of the structure.
The flank members C have a length of more than twice the length of one segment. They overlap each other, via FIGS. 6, 11 and 12 by means of a guide flange E (see FIGS. 1 and 7), mounted on or formed integrally with the back side of the top of each flange member C and disposed over the next flank member. The flank members C can slide passing one another without there being the danger of a secondary collision of the guide retainer E with the flank member of the following segment, because they have already passed one another in the original position. The advantage of a great length of overlapping is that it increases the lateral and vertical stability of the whole structure.
The flank members C are connected to the support members G by means of angled strips D (FIGS. 10-12). The strips D afford the flank members C a certain amount of movability with respect to the support member(s) G. This is necessary because in the event of a head-on collision and the successive telescoping of segments:
a. the angle formed by the flank members C with respect to the support members G may change;
b. the distance of the flank members C to the support members G may change; and
c. the flank members C must obtain some freedom so as to reduce the influence of mass inertia on the forces in the structure and on the deceleration of the vehicle.
In addition, in the event of a lateral collision:
d. the strips D provide an extra braking path and the flank members C undergo a smooth deformation.
As a result of the form of the angled strips N the movements in the horizontal plane as described can be realized while ensuring sufficient rigidity in the vertical direction. A proper vertical position of the support members G is a condition for the intended behavior of the box-like structure N.
Eccentric head-on collisions are understood to be those collisions in which the longitudinal axis of the vehicle runs parallel to but spaced from the longitudinal axis of the structure. In an angular head-on collision, the longitudinal axis of the vehicle forms an angle with the longitudinal axis of the structure.
If the vehicle strikes the obstacle protector means eccentrically or at an angle, the nose apron A' is intended to be deformed in such a way that the vehicle is not thrown back. To this end the nose apron A is provided with straight thin plates U (FIGS. 1 and 8a). Relative to their points of fastening, the plates U are capable of absorbing tension but no pressure. As a result, the nose segment will be inclined to hold the vehicle. (see FIGS. 17a and 17b).
If, in an eccentric or angular collision, the displacement in longitudinal direction is so large that the support member G' leaves the foundation guide member H, the whole obstacle protector structure is to be regarded as a projecting girder with respect to the supporting foundation L (see FIG. 13). The box-like structure N can absorb this force couple.
Another type of collision is a lateral collision. These collisions concern impacts of collision upon the flank of the obstacle protector means. In such an event the whole obstacle protector means forms a beam having as points of support the ground rail H and the supporting foundation L. The upper and lower plates P 1 and P 2 of the box N act, in the tension zone, as tension absorbers. The ripple tubes B act, in the pressure zone, as pressure absorbers (see FIG. 14). The foregoing describes the obstacle protector means having a box-like structure. This box-like structure N is an essential element for increasing the stability of the structure. An alternative form of embodiment for obtaining the stability is attained by replacing the box-like structure N by two crossed tension rod members F. (see FIG. 5). This alternative embodiment essentially functions in a manner identical with that of the form of embodiment having the box-like structure N. This form of construction with tension rod members likewise can be realized in a V-form and a parallel form.
The construction of the segments of this alternative embodiment is as follows. Between the support members G there are provided individual tubes B, whereupon parallel adjustment is effected by means of the tension rod members F. In the event of a lateral collision the compressive forces are again absorbed by the tubes B. Tensile forces are absorbed by the tension rod members F and the flank members C. For this purpose the flank members C have been internally provided with members J to prevent shifting under tension during lateral collision (FIG. 15). The members J are secured to opposed ends to the spaced flank members C by welds W to resist movement of the flank members C in a tension direction T. For the purpose of increasing the stability the crossed tension rod members may be connected together in the center.
Although the present invention has been shown and described in connection with preferred embodiments thereof, it will be apparent to those skilled in the art that many variations and modifications may be made without departing from the invention in its broader aspects. It is therefore intended to have the appended claims cover all such variations and modifications as all are within the true spirit and scope of the invention. | An obstacle protection arrangement composed of a series of interconnected deformable segments, each comprising a U-shaped support member and a box structure containing crumpling tubes. Both sides of the arrangement are formed by overlapping flank members such that during a front collision there will be dissipation of energy by deformation of the segments, whereas during a side collision the arrangement behaves like a rigid girder. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application of the same title and inventorship, Ser. No. ______ filed Mar. 4, 2004 which is hereby incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] Diabetes is a major cause of morbidity and mortality in industrialized societies. It has been estimated that one of every seven health-care dollars goes to treating diabetes and its complications. Type 1 diabetes (also called insulin-dependent or juvenile diabetes, henceforth referred to in this document as “diabetes”) is due to the autoimmune destruction of the insulin-producing pancreatic beta cells. Type 1 diabetes is less common than type 2, accounting for only 10-20% of cases in Caucasians. However, because it is much more severe and starts much earlier in life, it accounts for a large proportion of diabetes-related morbidity and mortality.
[0003] Autoimmune destruction of the pancreatic islet beta cells is the major cause of type 1 diabetes mellitus. 1 This destruction is associated with cellular and humoral immune responses to several beta-cell autoantigens, both of which can precede clinical onset of disease. Indeed, the presence of antibodies against glutamic acid decarboxylase (GADA), insulinoma-associated antigen (IA-2A) or insulin (IAA) alone or in combination has been shown to predict type 1 diabetes. 2,3 Together with islet-cell antibodies (ICA), IA-2A and GADA are present at the time of diagnosis in 80-90% of patients with type 1 diabetes. 4 These autoantibodies, especially GADA, may also occur in up to 10% of adults initially classified as type 2 diabetes, a condition referred to as Latent Autoimmune Diabetes in Adults (“LADA”). 5 The disease process in LADA patients is in some ways similar to that in type 1 diabetes in that they share some HLA genetic susceptibility and some type 1 diabetes-associated autoantibodies. In type 1 diabetes compared to LADA, however, insulin secretion is lower and the rate of progression to insulin dependency is higher. 6,7
[0004] Preclinical studies in the spontaneously non-obese type 1 diabetic (NOD) mouse demonstrated that the destruction of pancreatic islet beta-cells was associated with T cells recognising GAD65. 8 It was also shown that small quantities of GAD65 effectively prevented autoimmune beta-cell destruction and reduced or delayed the development of spontaneous diabetes. 8-14
[0005] Given the irreversibility of the destruction of pancreatic beta cells, it is desireable to provide a treatment for autoimmune diabetes where it cannot be otherwise prevented. Although the specific causative autoantigen(s) in diabetes is/are not known, insulin, the main product of the beta cell appears to be an autoantigen of major importance. Accordingly, it is desrieable to have safe and efficacious medications and treatment and prevention methods and regimes for autoimmune diabetes, as well as treatments for all diabetes types.
[0006] Based on the pre-clinical data presented herein, controlled clinical studies were initiated to assess the potential of recombinant human GAD65 to halt beta-cell destruction and prevent or reduce insulin dependence. Following extensive pre-clinical safety evaluation and one clinical phase I trial with the bulk rhGAD65 without adjuvant, a phase II study with rhGAD65 formulated with alum (the medication in accordance with the present invention) was conducted in LADA-patients. The study objectives were to investigate the clinical safety of the subcutaneously administered medication of the present invention, and to assess its impact on the immune system and diabetic status, and to identify an immunmodulatory dose level.
SUMMARY OF THE INVENTION
[0007] The present invention relates to methods and formulations for preventing autoimmune diabetes and for treatment of human diabetes in general.
[0008] In general terms, the invention includes a method of treating diabetes in a human comprising administering to a the human an effective amount of a human recombinant GAD65 protein and at least one adjuvant for an effective time so as to stimulate the production of insulin in the human to a level above that existing prior to the administration.
[0009] The administration may be by any acceptable means, such as by subcutaneous injection or use of an implant.
[0010] The adjuvant may be any pharmaceutically acceptable adjuvant substance, such as aluminum hydroxide.
[0011] The human recombinant GAD65 protein is administered in a dosage such that the human recombinant GAD65 protein is at a level of at least 20 micrograms, preferably in the range of from about 20 micrograms to about 500 micrograms.
[0012] Following the first administration of the human recombinant GAD65 protein, additional booster dosages may be given over a treatment period (typically 4-24 weeks), preferably at a level of at least 20 micrograms and most preferably in the range of from about 20 micrograms to about 500 micrograms.
[0013] The invention also includes a method of suppressing or reducing the immune response of a human to glutamic acid decarboxylase comprising administering to the human an effective immunosuppressive dose of human recombinant GAD65 protein, so as to help prevent autoimmune diabetes.
[0014] The administration methods, adjuvants, dosage and booster levels and ranges may be as given above.
[0015] The level of beta cell function may be determined through measurement of CD4+ lymphocytes prior to the at least one booster dosage as described herein.
[0016] The invention also includes a pharmaceutical composition for suppressing or reducing the immune response of a human to glutamic acid decarboxylase comprising a dosage form whose components comprise an effective immunosuppressive dose of human recombinant GAD65 protein and a pharmaceutically acceptable adjuvant.
[0017] The method of the present invention thus also includes generally a method to increase insulin production in a diabetes patient with beta cell antibodies, the method comprising administering to a human an effective amount of beta cell antigens in a pharmaceutical carrier for an effective time so as to stimulate the production of insulin in the human to a level above that existing prior to the administration.
[0018] The beta cell antigens that may be used in the method of the present invention include at least one from the group: GAD65, GAD67, insulin, insulin-peptide, proinsulin, proinsulinpeptide, sulfatide, heat schock protein, S100 beta protein, IA-2, or any peptide, altered peptide ligand, chimeric molecule, or conjugated molecule or fragment of any of the above.
[0019] The aforementioned mehthods may be practiced by replacing at least one of the beta cell antigens with DNA or RNA nucleotides coding for at least one from the group: GAD65, GAD67, insulin, insulin-peptide, proinsulin, proinsulinpeptide, sulfatide, heat schock protein, S100 beta protein, IA-2, or any peptide, altered peptide ligand, or by anti-sense oligos to at least one of the nucleotide.
[0020] These methods may be carried out with at least one of the aforementioned components are produced recombinantly in a prokaryotic expression system capable of posttranslational palmitoylation. This may be done with any appropriate expression system, such as for instance baculovirus is grown in Spodotera frugiperda 9 (Sf9) cells.
[0021] The administration of the antigen may be by any effective and appropriate method, such as subcutaneous administration, intravenous administration and oral administration; or by gene therapy.
[0022] Although all effective amounts are included in the subject disclosure, it is typical, and preferred, that each of the adminsitered components are administered in a dosage such that at least one of the components is in the range of from about 5 micrograms to about 100 micrograms or, in other terms, in the range of from about 0.001 mgs/kg to about 0.1 mgs/kg.
[0023] The method of the present invention may also include the optional administering of at least one booster dosage of the components following the first administration, and wherein the booster is administered in a dosage such that at least one of the components is in the range of from about 5 micrograms to about 100 micrograms.
[0024] The at least one booster dosage of the components preferrably is administered in a dosage such that at least one of the components is in the range of from about 0.001 mgs/kg to about 0.1 mgs/kg.
[0025] The method of the present invention may also be described as a method to treat beta cell inflammation by means of in vivo activation of regulatory CD4+CD25+ T cell subsets. This may be done as a method to activate regulatory CD4+CD25+ T cells by means of administering an effective amount of at least one components described above.
[0026] The invention also includes a pharmaceutical composition for treatment of diabetes comprising of at least one of the aforedescribed components where at least one of the components is produced according to the methods of the present invention described herein.
[0027] The invention also features a pharmaceutical composition as descrtibed herein, preferrably wherein Zwittergent is included in a concentration relation to at least one of the components in a relative ratio of between about 1:1 to about 1:8. The preferred pharmaceutical composition includes a pharmaceutical carrier such as alum, preferrably species specific serum albumin, such as human serum albumin.
[0028] One of the findings are that an effective dosing regimen, such as a 20 microgram dose prime and boost regimen, improves beta cell function in most patients and that this can be verified by looking at an increase in a subset of CD4+ lymphocytes namely the CD4+CD25+ lymphocytes. The increase may be measured in absolute terms or CD4+CD25+ in relative terms such as the quotient CD4+CD25+/CD4+CD25.
[0029] If an increase of CD4+CD25+ cells is not seen a reboost may be given. If no increase another reboost. In fact to look for an increase in CD4+CD25+ cells is a way to look for efficacy of other treatments for other autoimmune diseases as well.
[0030] It has also been found that the medication of the present invention not only maintained the beta cells' capacity to produce insulin (measured as C-peptide) which was expected—but indeed, unexpectedly did the insulin production increase significantly (measured as c-peptide). This means that the present invention may have allowed new beta cells to regenerate and to produce more insulin. It may also mean that the present invention may have turned off the inflammation in the beta cells and thus cleared the milieu so that increased insulin production was allowed. So the present invention may now bee used as a treatment for type 1 and type 2 diabetes, not only a vaccine to avoid acquiring type 1 diabetes.
[0031] A study of the treatment in acorodnace with the present invention determined that alum-formulated human recombinant GAD65 given to patients with Latent Autoimmune Diabetes in Adults (LADA) is safe and does not compromise beta cell function, and was aimed at identifying an immunomodulatory dose for further clinical development.
[0032] This study was conducted as a randomised, double blind, placebo-controlled, dose-escalation clinical trial in a total of 47 LADA patients who received either placebo or 4, 20, 100 or 500 μg of the medication in accordance with one embodiment of the pre subcutaneously at weeks one and four. Safety evaluations including neurology, beta-cell function tests, diabetes status assessment, haematology, biochemistry and cellular and humoral immunological markers were repeatedly assessed over 24 weeks.
[0033] None of the patients had significant study-related adverse events. Fasting c-peptide at 24 weeks increased compared to placebo (p=0.0011) in the 20 μg but not in the other dose groups. In addition, both fasting (median 36%, p=0.008) and stimulated (median 19%, p=0.0156) c-peptide increased from baseline to 24 weeks in the 20 μg dose group alone. GADA levels clearly increased (p<0.001) in response to 500 μg of the medication of one embodiment of the present invention. An increase in CD4 + CD25 + /CD4 + CD25 − T cell ratio was positively correlated with a change in fasting (r=0.51; p<0.005) and stimulated (r=0.34; p<0.05) c-peptide levels over 24 weeks.
[0034] The positive findings of this study of clinical safety and efficacy supports further clinical development of the present medication compositions and treatments as a therapeutic to prevent autoimmune diabetes.
[0035] It is an object of the present invention to provide a method for treating autoimmune diabetes in man.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] FIGS. 1A-1E are graphs of the percentage change in log GAD antibody levels (U/ml) before and at 4, 8, and 24 weeks from prime dose of the medication of the present invention, wherein the individual patients in the (A) Placebo, (B) 4 μg, (C) 20 μg, (D) 100 μg dose and (E) 500 μg dose groups are shown, in accordance with one embodiment of the invention.
[0037] FIGS. 2A-2C are graphs of the median percentage change before and at 8, 12 and 24 weeks from prime dose shown for the placebo, 4 μg, 20 μg, 100 μg and 500 μg dose groups, respectively as follows: (A) Effects on HbA 1,c ; *p=0.013, (B) Effects on fasting c-peptide/glucose; *p=0.0078 and + p=0.0008, and (C) Effects on post-Sustacal® c-peptide/glucose. *p=0.0391 at 20 μg and p=0.0312 at 500 μg, in accordance with one embodiment of the invention.
[0038] FIGS. 3A and 3B are graphs of the mean change before and at 8 and 24 weeks from prime dose are shown for the placebo, 4 μg, 20 μg, 100 μg and 500 μg dose groups in respectively as follows: (A) CD4/CD8 ratio, and (B) CD4 + CD25 + /CD4 + CD25 − ratio, showing an increase in the ratio of CD4 + CD25 + /CD4 + CD25 − cells over time (*p=0.012) and relation to placebo ( + p=0.03), in accordance with one embodiment of the invention.
[0039] FIGS. 4A and 4B are graphs of results showing change in fasting C-peptide levels in individuals studied in accordinace with one embodiment of th method of the present invention.
[0040] FIGS. 5A-5Y are graphs of results from this a phase II cliical study in accordance with one embodiment of the present invention.
[0041] FIG. 6 is a graph describing induction of GAD65-specific regulatory T cells in NOD mice.
[0042] FIG. 7 is a chart describing the patient disposition in a Phase II trial conducted using a method in accordance with one embodiment of the present invention.
[0043] FIG. 8 is a graph describing C-peptide/glucose at 6 months, 12 months and 18 months in a Phase II trial conducted using a method in accordance with one embodiment of the present invention.
[0044] FIG. 9 is a graph describing the log of fasting C-peptide/fasting glucose at 6 months, 12 months and 18 months in a Phase II trial conducted using a method in accordance with one embodiment of the present invention.
[0045] FIG. 10 is a graph describing HbA 1c (%) at 6 months, 12 months and 18 months in a Phase II trial conducted using a method in accordance with one embodiment of the present invention.
[0046] FIG. 11 is a graph describing the log of GAD65Ab at 6 months, 12 months and 18 months in a Phase II trial conducted using a method in accordance with one embodiment of the present invention.
[0047] FIG. 12 is a graph describing the change in CD4 + CD25 + /CD4 + CD25 − T cell ratio in a Phase II trial conducted using a method in accordance with one embodiment of the present invention.
[0048] FIG. 13 is a graph describing the percent of treated and control LADA patients receiving insulin in 24 Months in a Phase II trial conducted using a method in accordance with one embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0049] In order to treat autoimmune diabetes, the following provides an example of one embodiment that demonstrates the safe efficacy of the present invention. This is considered to be the best mode of the invention.
[0000] Trial Design
[0050] The study design was a randomised, double blind, placebo-controlled, group comparison, dose-escalation study conducted in LADA patients at the Department of Endocrinology, University Hospital MAS, Malmö, and the Department of Medicine, St. Görans Hospital, Stockholm, Sweden. A total of 47 patients were allocated to either one of four groups receiving 4 (n=9), 20 (n=8), 100 (n=9), or 500 μg (n=8) of the medication of the present invention, or placebo (n=13). Sequential immunisation of each dosage group was conducted once the absence of safety issues were determined at lower doses. Interim safety evaluation to approve dose escalation was conducted by a separate committee 4 weeks after receipt of an injection of the medication of the present invention. In each group, nine patients were planned to receive the medication of thee present invention, and three to receive placebo. Patients treatment allocation was centrally organised by Chiltern International Ltd., Slough, Berkshire, UK.
[0051] Patients were eligible to enter the trial if they fulfilled the following entry criteria at Visit 1:1) male or female patients aged 30-70 years, 2) diagnosed with diabetes and classified with type 2 diabetes within the previous 5 years, 3) presence of GADA, 4) only requiring diabetes treatment with diet, oral hypoglycaemic agents, or both, 5) females of non child-bearing potential, 6) absence of associated serious diseases or conditions which in the opinion of the investigator would exclude the patient from the trial, and 7) patients who had given written informed consent at the screening visit.
[0052] After all patients in the 4 μg dosing group had completed visit 8 (week 8), and provided that there were no safety concerns, the next schedule of visits for the 20 μg dosing group was initiated. The same procedure was repeated for the 20, 100 and 500 μg groups. In addition, a maximum of two additional booster injections was allowed in the 500 μg dose group alone depending on the patients GADA response. The criterion for additional booster injections in the top dose group were a GADA titre that remained unchanged at week 8 (defined as less than a doubling of titre prior to receipt of the first dose) and the absence of safety concerns for that patient. A final booster injection (i.e. 4 th administration) was performed if there was still no change in GADA titre four weeks after the initial booster injection and if no safety concerns were apparent. All patients stayed at the hospital overnight for safety observation after each injection.
[0053] During the 24-week study period, each patient was followed at regular intervals as outpatients with a total of 10 study visits during which assessment of immunological markers, diabetic status, fasting lipids, haematological and biochemical parameters, as well as physical examinations, reporting of concomitant medication and adverse effects were performed. GADA and IA-2A were determined as previously described. 15 Our laboratory is number 156 in the Diabetes Antibody Standardisation Program (DASP) for GADA and IA-2A. 16 Diabetes status assessment included fasting glucose, fasting and 2-hr Sustacal® stimulated c-peptide, and long-term metabolic control assessed by HbA 1c . Blood samples for haematology were analysed for haemoglobin, red cell count (including MCV and MCHC), haematrocrit ratio (PCV), white cell count, differential white cell count and platelets, and biochemical parameters included analysis of plasma levels of glucose, c-peptide, HbA 1c , urea, creatinine, phosphorus, total bilirubin, alkaline phosphatase, alanine transferase, glutamyl transferase, lactic dehydrogenase, amylase, albumin, c-reactive protein, total protein and fasting lipid and lipoproteins. Clinical neurological assessment and EMG were performed at baseline and after 6 months to detect any adverse effects on the neuromuscular system. 17,18
[0000] Patients
[0054] Patient characteristics for patients receiving placebo and for the four dose groups at baseline are given in Table 1. All patients remained in the study for 24 weeks. One patient given placebo started insulin treatment at 12 weeks along with one patient in each of the 100 μg and 500 μg groups, who started insulin treatment after 12 but before 24 weeks. At week 24, only fasting c-peptide was available from these patients. For technical reasons, c-peptide were not available at week 24 from one patient in the placebo (fasting) and another in the 100 μg (stimulated) group, respectively. Three patients did not complete the study for personal reasons, one each in the 4, 20 and 100 μg groups.
[0000] Test Substances
[0055] Sterile, pre-filled vials of the medication of the present invention were provided by Diamyd Therapeutics AB, Stockholm, Sweden for clinical trial use. The unmodified recombinant form of human GAD65 (bulk rhGAD65) was formulated with aluminium hydroxide, such as that sold under the trademark Alhydrogel®. The bulk rhGAD65 was manufactured using baculovirus/insect cell expression of the cDNA for hGAD65. 19 Both manufacture of the bulk rhGAD65 and that of the medication of the present invention were performed under strict conditions of current Good Manufacturing Practice. Each vial contained a sterile formulation of either 4, 20, 100, or 500 μg of the medication of the present invention having a constant amount of Alhydrogel®. Coded vials containing an identical amount of Alhydrogel® alone were used as placebo.
[0000] Flow Cytometric Analysis
[0056] Flow cytometric analysis of lymphocyte subsets was conducted using standard techniques. Whole blood was stained at room temperature for 20-30 minutes with monoclonal antibodies against CD3, CD4, CD8, CD25, CD19, CD56 and CD16 (all from Becton Dickinson, California, USA). Erythrocytes were lysed using a FACS® tradeamrk lysis buffer containing paraformaldehyde (Becton Dickinson, CALIFORNIA, USA). Thereafter, cells were washed, resuspended in staining PBS buffer containing 0.5% bovine serum albumin and 2 mM EDTA (pH 7.4) and analysed within 24 hrs using a FACSCalibur® (Becton Dickinson, Franklin Lakes, N.J., USA) and CellQuest® software (Becton Dickinson). Between 10,000 and 50,000 events were acquired and the absolute number of each subset was calculated by multiplying the percentage of cells by the total lymphocyte count obtained at the hospital clinical laboratory for the same blood sample. Isotype-matched control antibodies (IgG2a FITC) were used to set the dot plot quadrant and calculate the percent of CD4 + CD25 + lymphocyte population.
[0000] Statistical Analysis
[0057] All graphs and analyses were performed using Splus6.1 (from Insightful Corp., Seattle, Wash.). Two-sample t-test was used for differences in means between variables normally or symmetrically distributed. When distributions were not symmetric, medians were used as a summary measure and the corresponding Wilcoxon two-sample test was used to evaluate statistical significances. Change in plasma glucose, c-peptide and HbA 1c for each subject was presented as percent change in level from baseline. Change in T cell counts was summarised as change in ratio totals. Multiple linear regression was used to test whether differences observed in the univariate analyses remained after adjusting for variables such as age, BMI and gender as well as GADA and IA-2A. C-peptide was log transformed to assure normality and constant variance assumption. The 4 μg dose group was considered as having no effect and was therefore combined with placebo as controls and compared to a treatment group. Spearman's correlation coefficient tested the association between change in c-peptide levels and change in CD25 + /CD25 − composition within CD4 + T cells. P-values less than 0.05 were considered significant.
[0000] Results
[0000] Study-Related Adverse Events
[0058] There were 32/47 patients (68%) with 51 adverse events (AE). The majority experienced influenza-like symptoms, with nasopharyngitis being the most common AE. Prior to study completion and unbinding three AEs were judged to be probably related to the trial treatment, i.e. vitiligo (later found to be in the placebo group), mild leukocytosis (100 μg dose group) and a mild inflammation at the injection site on the left arm (500 μg dose group). As a precautionary measure the patient with vitiligo was withdrawn from the trial two weeks after the first injection. However, leukocytosis and inflammation were completely resolved in the two other patients and no separate treatment was required. There were no severe AEs or deaths during the trial.
[0059] Injection site reactions were absent at the majority of visits. All reactions were mild and most, in particular tenderness, occurred primarily on the day of the first injection (day 1) and on the day of the second injection (week 4).
[0060] Mean haematology and biochemistry parameters were within normal limits in each treatment group at most visits. There were no significant changes from baseline (day 1) in any of the parameters except for two patients had abnormal clinically significant laboratory results; one patient (20 μg dose group) having raised liver enzymes and another (placebo dose group) having raised blood iron levels, later diagnosed with haemochromatosis.
[0061] There were no differences between treatment groups in blood pressure or pulse rate, no deterioration in neurological assessment, muscle tone and spasms, and no abnormal EMG assessments.
[0000] GAD65 Autoantibody (GADA) Levels
[0062] The percentage change in GADA levels from day 1 for all patients and all groups indicate no change after 1, 4 (when the boost injection was given), 8 and 24 weeks in the placebo ( FIG. 1A ) and 4 μg ( FIG. 1B ) groups. Levels in the 20 μg dose group did not change during the first 4 weeks; however, between 8 and 24 weeks ⅞ (88%) patients showed a decline ( FIG. 1C ). Similarly, in the 100 μg dose group there was a decline in 8/9 (89%) patients despite an increase in three patients between 4 and 24 weeks ( FIG. 1D ). In these two groups the number of patients with a decline ( 15/17) was different from the placebo group ( 6/13; p<0.05). All eight patients in the 500 μg group developed either an early increase before week 4 or a gradual increase after additional boost injections during the 24 weeks ( FIG. 1E ).
[0000] Blood Glucose and HbA 1c Levels
[0063] There were no changes in fasting blood glucose during the first 24 weeks. Within the placebo group, however, there was considerable variability in percentage change. An increase in HbA 1c levels (p=0.01) was found in the placebo but not in the other dose-groups ( FIG. 2A ).
[0000] Fasting and Sstimulated C-Peptide
[0064] The groups did not differ in fasting c-peptide levels at visit 2 (Table 1). However, the 20 μg dose group showed an increase in fasting c-peptide compared to placebo (p=0.0011) as well as an increase in both fasting (36%, p=0.008) and stimulated (19%, p=0.0156) c-peptide at 24 weeks. This effect was also evident when the data were calculated as a function of c-peptide/glucose ( FIGS. 2B and C) and compared to both baseline (47% increase, p=0.0078) and to placebo (p=0.0008) ( FIG. 2B ). An increase in levels compared to baseline within the 20 μg group was also recorded in stimulated c-peptide/glucose (24% increase, p=0.0391) ( FIG. 2C ). A decline in stimulated c-peptide/glucose levels was apparent in the 500 μg dose group (p=0.03). Patients given placebo or the 4 μg dose had almost identical changes in c-peptide/glucose ratio during the 24 weeks follow-up ( FIG. 2C ).
[0000] Blood Lymphocytes and T Cell Subsets
[0065] At day 1 and during the 24 weeks of observation no differences between the groups were observed in total CD3 + , CD4 + , or CD8 + T cells, B cells, NK cells or T cells with NK cell markers or in the CD4 + /CD8 + T cell ratio (data not shown). In contrast, we observed that the ratio of CD4 + CD25 + /CD4 + CD25 − T cells increased (p=0.012) over time in the 20 μg group, but not in the other groups ( FIG. 3 ). This change was also different from the placebo group (p=0.03, FIG. 3 ). There was a positive correlation in all medication-treated patients between change in CD4 + CD25 + /CD4 + CD25 − T cell ratio and change in fasting c-peptide (r=0.51; p<0.005) as well as in post-Sustacal® c-peptide (r=0.34; p<0.05), demonstrating that patients exhibiting an increase in c-peptide also had an increase in CD4 + CD25 + /CD4 + CD25 − T cell ratio.
[0000] Multiple Linear Regressions
[0066] Changes in HbA 1c , fasting glucose, fasting and stimulated log c-peptide in the control (n=21) were compared to the treatment (n=24) group. Unadjusted analyses confirmed the increase compared to controls in fasting log c-peptide (+0.208, p=0.025) and a decrease in HbA 1c (−0.603, p=0.024). The effect on fasting log c-peptide remained after adjusting separately for age, gender, BMI, HbA 1c at baseline as well as GADA and IA-2A.
[0000] Findings and Discussion
[0067] The results of the study support the clinical safety of subcutaneous administration of alum-formulated recombinant human GAD65 as well as its ability to increase c-peptide levels and affect the CD4 + CD25 + T cell subset in peripheral blood.
[0068] Cutaneous reactions to the treatment of the present invention were minor and of no clinical significance. These findings support the results of a phase I clinical study demonstrating that subcutaneous administration of rhGAD65 was well-tolerated. In the study of the present invention, inclusion of a patient group receiving a provisional no effect dose level (4 μg) was intended to provide clinical outcomes indistinguishable from placebo and from which dose escalation could be safely performed. The additional booster injections with 500 μg of the medication of the present invention were intended to maximise the likelihood of immunomodulation resulting therefrom (apparent as a doubling in GADA). Three patients in the 500 μg dose group received additional injections. Of these, two patients received one additional injection (a total of 3 injections) and one patient received two additional injections (a total of 4 injections). No study-related adverse events were observed in any of the patients in the 500 μg group despite a more than two-fold increase in GADA. The stimulatory effects of 20 μg of the medication of the present invention on both fasting and stimulated (post-Sustacal®) c-peptide was observed when the patients were either compared to their change from baseline or when compared to the placebo group. It is possible that the c-peptide response to the medication of the present invention is dependent on both the dose and the individual since some of the patients receiving 100 μg of the medication also showed an increase in fasting c-peptide levels. It is also noted that patients receiving 500 μg of the medication tended to show a decline in fasting c-peptide, indicating a possible dose dependent effect. The effects of 20 μg of the medication on both fasting and stimulated c-peptide were statistically significant whether or not these were calculated as c-peptide/glucose ratio or c-peptide levels alone. As the increase in c-peptide levels in the 20 μg medication dose group was not associated with a corresponding decrease in HbA 1c levels, the increase in c-peptide was probably not an effect of decreased glucose toxicity on the beta cell. However, the positive correlation of CD4 + CD25 + T cells to the increase in c-peptide in the 20 μg dose group suggests an immunomodulatory mechanism. Further evidence for immunomodulation is provided by the median decline in log GADA after 20 μg (−0.17 U/ml) and 100 μg (−0.33 U/ml) of the medication, indicating a possible suppressive effect on GADA production. This suppressive effect may be explained by an increase in CD4 + CD25 + T cells since the CD4 + /CD25 + /CD4 + CD25 − ratio among patients in either the 20 or 100 μg dose groups showing a decline in GADA correlated to an increase in fasting c-peptide (r 2 =0.83; p<0.005). These results also support the increase in c-peptide being related to a quantitative increase in CD4 + CD25 + T cells.
[0069] CD4 + CD25 + T cells are regarded as regulatory T cells 20,21 and in experimental animals their presence confer inhibition of autoimmunity. 22 Although not limited by the mechanism of the invention, several mechanisms may explain the positive effect on c-peptide levels in patients receiving 20 μg (and in some receiving 100 μg). First, 20 μg of the medication may induce specific T cells recognising immunodominant GAD65 epitopes. These GAD65-specific regulatory T cells would down-regulate existing GAD65 autoreactive T cells and thereby preserve c-peptide. As a second possibility, non-antigen specific CD4 + CD25 + T cells may be induced in numbers sufficient to allow their detection in peripheral blood. 23 As such, CD4 + CD25 + T cells were shown to be immuno-suppressive 24 their greater number could possibly down-regulate self-reactive T cells, thereby inhibiting T-cell-mediated beta cell killing. As no changes in other lymphocyte subsets were found, the present treatment could be considered immunologicaly safe with regard to its clinical impact on peripheral lymphocytes.
[0070] The effect of the medication of the present invention may be highly dose dependent, as is well-known in specific immunomodulation of certain allergies. In addition to T cell subset immunomodulation, administration of the medication may also impact on B cell activity, since GADA levels in the 20 μg and all but three patients in the 100 μg dose groups tended to decrease over time. Indeed, it cannot be excluded that therapeutic activity also extends to the 100 μg dose level, since some of these patients showed an increase in fasting c-peptide that was associated with an increase in CD4 + CD25 + ratio and a decrease in GADA. Although it is possible that the immune response to administration of low levels of the medication involves a shift towards less aggressive cytokines produced by certain T cell subsets, the effect of 20 μg dose does not suggest a shift from a Th1 to a Th2 response, as this would otherwise be indicated by an increase in GADA. 13 Rather, because of their reported regulatory activity 20,21 and their demonstrated decrease in conditions of autoimmunity, 22,23 the induction of CD4 + CD25 + T cells by low doses of the medication suggest a novel mechanism by which autoimmunity is down-regulated.
[0071] GAD65 immunomodulation in GAD65 autoantibody positive type 2 diabetes patients was studied to determine the immunomodulation of GAD-specific autoimmunity as a potential therapy of type 1 diabetes. A phase II clinical trial on 47 GAD65 autoantibody positive type 2 diabetes patients previously reported no severe adverse events after six months. The primary aim was to examine if the proposed invention was still clinically safe after 12 months. A secondary goal was to determine whether GAD65 administration prevents progression to insulin dependency after one year. Patients with LADA received placebo or 4, 20, 100 or 500 μg subcutaneously at weeks 1 and 4 in a randomised, double blind, group comparison dose-escalation study. Beta-cell function tests were performed at 2, 6, 9 and 12 months. The 4 μg was a non-effect dose group and therefore combined with placebo to form a control group. None of the patients showed significant study related adverse events and there was no sign of beta-cell collapse. While 4 of 47 received insulin before 6 months, 7 of 43 patients became insulin dependent between 6 and 12 months, and an additional 3 of 43 dropped out for unrelated reasons. Of these insulin-dependent patients 6 of 19 where controls, 1 of 8 was given 20 μg, 0 of 7 100 μg and 0 of 6 500 μg doses (p<0.05). Of the remaining 33 patients followed for the entire year, HbA1c level at the start of the study in treatment patients correlated with a decline over 12 months (n=20; r=0.84; p<0.0005), but no such association was seen in the control group (n=13; r=0.32; p=NS). Fasting and stimulated C-peptide levels, which increased in the 20 □g dose group after first 6 months, remained unchanged in the second 6 months. One year follow-up confirm that alum-formulated recombinant human GAD65 is safe. Patients receiving 20 μg show no evidence of further decline in beta-cell function between 6 and 12 months. FIGS. 5A-5Y are graphs of results from this a phase II cliical study in accordance with one embodiment of the present invention.
[0072] In conclusion, the main outcomes of this phase II clinical trial support the clinical safety of the treatment and prevention methods of the present invention, together with evidence for the therapeutic efficacy of a 20 μg dose as reflected by an increase in both fasting and stimulated c-peptide. Evidence for this effect being mediated by an increase in regulatory T cells was also obtained.
[0073] Additional data was also obtained from an 18 month and 24 month follow-up study as described below.
[0000] Therapeutic Rationale
[0074] The majority of patients with insulin dependent (Type 1) diabetes, and also a 10% subset of non-insulin dependent (Type 2) diabetes patients (i.e. those with antibodies to GAD65), are currently recognised as having an autoimmune form of diabetes.
[0075] Although the contribution by the different components of the immune system is different for different autoimmune diseases, it is generally understood that the destructive process in autoimmune diabetes is orchestrated and executed by T lymphocytes, not antibodies. While this destructive process is primarily contributed to by autoreactive cytotoxic T lymphocytes (i.e. displaying the CD8+ cell surface marker) their activity is controlled by another lymphocyte subclass, T “helper” cells (instead displaying the CD4+ marker). T helper cells are therefore providing important regulatory functions in the activity of cytotoxic lymphocytes, and their manipulation provides a potent target for therapeutics to treat or prevent autoimmune diseases.
[0076] Interest in GAD65 in Type 1 diabetes stems from observations in the 1980s of the frequent occurrence (˜90%) of antibodies to GAD65 in patients with insulin-dependent diabetes. Since then, the clinical presence of GAD65 antibodies has become increasingly accepted as both a diagnostic and prognostic marker for this disease. Most importantly pre-clinical and clinical studies have confirmed the GAD65 protein as the most important autoantigen in the prediction and prevention of autoimmune diabetes.
[0077] In animal models for different autoimmune diseases, the appropriate administration of the autoantigen itself has been found capable of precipitating, as well as preventing, the associated autoimmune disease. These findings therefore provide strong support for the involvement of specific antigens in the aetiology of autoimmune diseases and also, conversely, of the possibility for “antigen-specific tolerisation therapies” in their treatment and cure.
[0078] Briefly, tolerisation involves the appropriate presentation of the autoantigen itself back to the immune system to enable an immune “re-programming” process to occur. It seems that the appropriate dose regimen, i.e. the quantity, route, frequency, adjuvant etc required for each autoantigen/autoimmune disease, is critical in determining which of several tolerisation mechanisms are activated. If the appropriate immune mechanism is engaged, then tolerisation to that autoantigen will occur and autoimmunity will be extinguished.
[0079] By way of background, in November 1993, two independent research groups in the U.S. simultaneously reported (in the scientific journal “Nature”) that administration of microgram quantities of GAD65 could induce tolerance and prevent insulin requirement in the NOD mouse pre-clinical model. Since then, the capability of GAD65 as a toleragen to prevent autoimmune diabetes has been confirmed experimentally in several independent laboratories. These include research groups at UCLA (Tian et al), Stanford (Tisch et al), Hopital Necker (Pleau et al) and University of Calgary (Yoon et al).
[0080] The immune mechanisms involved in GAD65 tolerisation in NOD mice have since been intensely investigated. Several published reports now support this type of immunomodulatory mechanism being evoked early in GAD65 tolerisation, and the down-regulation in autoimmunity that this induces is sufficient to preserve beta cell function and prevent exogenous insulin requirement.
[0081] Particularly because of close similarities in the NOD mouse model to its clinical counterpart, these pre-clinical findings support the possibility of rhGAD65 administration providing a clinical therapeutic for the prevention and treatment of autoimmune diabetes. Accordingly, administration of microgram quantities of alum-formulated rhGAD65 (referred to as “Alhydrogel-Diamyd™”) via an immunomodulatory “prime-and-boost” dose regimen to patients with autoimmune diabetes is proposed for therapeutic evaluation. The intended preservation of beta cell function is proposed to be clinically manifested by an increase in levels of insulin (or its surrogate: C-peptide) and result in prevention or delay in time to insulin requirement in diabetes patients with GAD65 antibodies.
[0000] Target Product Profile
[0082] The target product profile is supported by experimental data, but remains to be confirmed through continued clinical trials.
Property Target Product Profile Indication Indicated for the treatment of Type 1 diabetes patients and Type 2 diabetes patients with GAD antibodies Contraindications None identified in clinical trials conducted to date Dosage 20 μg Dosage Regimen Initial prime followed by a boost after one month. Additional boost after six months if indicated by a decrease in or unchanged C-peptide levels Yearly boosts thereafter if indicated by a decrease in C-peptide levels compared to previous visit If decrease or unchanged C-peptide levels after three injections (one prime and two boosts) the treatment is terminated Efficacy >30% increase in C-peptide levels in fasting patients. Maintained or decreased existing insulin requirement (as a measure of beta cell function) Shelf Life 3 years
Clinical Development
[0083] Clinical trials have been conducted with the Diamyd™ product available at different stages in development. The first clinical study used “laboratory grade” Diamyd™ Bulk Drug in a skin “prick test” study in selected volunteers. This was followed by a Phase I clinical trial in volunteers using GLP-grade Diamyd™ Bulk Drug from the commercial manufacturing process. The Phase II clinical trial in LADA patients has recently been completed with the (GMP) Alhydrogel-Diamyd™ formulation.
Study Individuals Study Location & Study (& Study Study Type CRO dates Number) Endpoint(s) Outcome Skin Sweden 11 Feb Type 1 Delayed No DTH Prick-Test (Karolinska 1995 Diabetics Type Reactions to GAD Hospital) (7) Hyper- No AEs & Healthy sensitivity controls (DTH) (8) Phase I UK Jan-Dec Healthy Safety/ Safe (Pharmaco,-LSR) 1999 volunteers Tolerability Well-tolerated (24) Phase II Sweden May 2001-Apr 2003 LADA Safety/ No treatment (Chiltern Patients Efficacy related AEs International) (47) Efficacy in 20 μg dose group (C-peptide) Immuno- modulation demonstrated
Phase II
Study Design
[0084] A Phase II randomized, double blind, placebo controlled, group comparison dose escalation study was performed in a total of 47 patients. The study was designed to assess both safety and efficacy of treatment with Alhydrogel-formulated Bulk drug (Diamyd™).
[0085] Patient disposition is shown in FIG. 7 . There were 39 males (83.0%) and 8 female (17.0%) patients randomised in the trial. There was a similar number of female patients in the placebo, 4 μg , 20 μg, and 100 μg dose groups, however there were no female patients in the 500 μg dose group.
[0086] All study groups were comparable with regard to age, BMI, and basal levels of fasting glucose, fasting and meal-stimulated C-peptide, and HbA 1c as seen in Table 1 below.
Baseline Characteristics Group 1 Group 2 Group 3 Group 4 Placebo (4 μg) (20 μg) (100 μg) (500 μg) n 13 9 8 9 8 Age (years) 56 (37-66) 58 (39-69) 57 (48-67) 57 (30-69) 53 (39-62) Males (n) 12 7 6 6 8 Log GADA (U/ml) 4.6 (3.3-13.3) 5.0 (3.9-9.4) 4.1 (3.5-7.3) 3.8 (3.4-7.8) 4.7 (3.3-7.5) BMI (kg/m 2 ) 26 (23-32) 27 (20-35) 28 (23-33) 27 (20-39) 26 (21-33) HbA1c (%) 5.9 (4.7-7.4) 6.7 (5.5-10.9) 5.9 (5.1-9.9) 6.0 (4.6-7.1) 6.0 (5.4-8.1) P-glucose (mmol/L) Pre-Sustacal 7.8 (5.5-9.5) 9.6 (5.9-15.8) 9.1 (6.3-17.4) 7.7 (6.2-9.0) 9.1 (6.3-15.1) P c-peptide (nmol/L) Pre-Sustacal ® 0.67 (0.3-1.7) 0.6 (0.3-1.6) 0.7 (0.5-1.4) 0.7 (0.3-1.5) 0.6 (0.3-1.8) Post-Sustacal ® 1.6 (0.5-3.7) 1.3 (0.7-2.9) 1.5 (1.0-2.0) 2.0 (0.6-3.9) 1.3 (0.8-5.1) IA-2A positive (n) 1 0 2 1 1 Total T-cells (×/10 9 /L) 1.3 (0.7-2.0) 1.1 (0.8-1.6) 1.3 (0.8-2.0) 2.0 (0.9-2.4) 1.1 (0.6-2.0) CD4+/CD8+ ratio 1.7 (0.8-3.8) 1.6 (0.7-9.3) 1.2 (0.8-3.2) 1.8 (1.1-4.9) 1.9 (1.0-3.0) CD4+ CD25+/ 0.18 (0.05-0.27) 0.20 (0.17-0.32) 0.15 (0.08-0.27) 0.20 (0.07-0.28) 0.09 (0.03-0.35) CD4+ CD25− ratio Median values (range) are shown
Study Endpoints
[0087] Apart from routine safety variables such as Clinical Examination and Adverse Event reporting and assessment, special emphasis was put on evaluating the impact of treatment on the patients diabetic status.
[0088] Efficacy parameters included Blood Glucose, HbA 1c and C-peptide levels (both fasting and meal-induced). These were measured on day 1, and at 1, 2, 3 and 6 months after initial treatment. In addition, antibody and lymphocyte parameters were assessed to investigate the impact of treatment on the patients immune system. These included antibody assays for autoantigens recognised as being involved in the autoimmune diabetes (GAD65, insulin, IA-2, and ICA), and lymphocytes potentially involved in the autoimmune process. These assays included FACS on whole blood for lymphocyte subsets, ELISPOT analysis of frozen polymorphonuclear cells from blood, and ELISA for serum cytokines.
[0089] Immunoassays were performed on patient samples obtained from visits on day 1, and weeks 1, 4 (i.e. immediately pre-boost), 5 (i.e. 1 week post-boost), 8, and 24. These immunoassays will be performed at month 9 and 12 during the first 6 months of the 4.5 year study follow-up, and then for GAD Ab titre alone every 6 months for the remaining 4 years.
[0090] Standard Haematology and Biochemistry analyses were performed at screening, day 1, and weeks 1, 2, 4, 8, 12 and 24.
[0000] Clinical Safety
[0091] There were no SAEs or deaths during the trial. There were 32/47 patients (68%) with 51 AEs. The majority of patients in each treatment group had at least one AE, most of which were due to influenza-like symptoms, with nasopharyngitis as the most common AE.
[0000] Clinical Efficacy
[0000] C-peptide at 6 Months, 12 Months and 18 Months:
[0092] A 36% (p=0.008) increase in fasting and a 19% (p=0.0156) increase in meal-stimulated C-peptide levels at week 24 were seen in the 20 μg dose group. The increase in fasting C-peptide was significantly different compared to placebo (p=0.0011). The effect appeared to be maintained troughout the study period (18 months) No other statistically significant changes in C-peptide were seen in the other dose groups.
[0093] The increase in fasting plasma C-peptide seen in the 20 μg dose group was also evident when the data were normalised for glucose and compared to either baseline (47% increase, p=0.0078) or placebo (p=0.0008). An increase in meal-stimulated C-peptide/glucose (24% increase, p=0.0391) compared to baseline was also observed within the 20 μg group.
[0094] Patients given placebo or the 4 μg dose had almost identical plasma C-peptide/glucose ratio during the 24 weeks follow-up, inferring the absence of impact in the 4 μg dose group and supporting this as being defined a “no-effect” dose level. However, over the 18 months follow-up period a small gradual increase in the C-peptide/glucose ratio was seen. This was however not statistically significant. HbA 1c .
[0095] A steady gradual increase in HbA 1c levels (p=0.01) was found in the placebo but not in the other dose-groups, inferring a reduction in glycemic control as diabetes progressed in untreated patients through the 18 months study period. A greater trend towards elevated HbA 1c levels was indicated for the placebo, 4 μg dose group, than for the 100 μg dose group, suggesting, in contrast, an improvement in glycemic control in patients receiving the latter dose level. In the 20 μg dose group in particular a decrease in HbA 1c levels was seen throughout the 18 month follow-up period indicating an improvement in glycemic control.
[0096] The average rate of change in HbA 1c per month was statistically significant compared to placebo in the 20 μg dose group (P20 01 ) which was estimated by a linear mixed model assuming random intercepts and slopes.
Rate of change per month compared to placebo group 95% Cl Placebo group Mean Difference Reference p-value 4 μg dose group −0.05 (−0.12, 0.03) 0.20 20 μg dose group −0.09 (−0.17, −0.02) <0.01 100 μg dose group −0.07 (−0.14, 0.00) 0.06
Impact on Patient Immune System:
GAD65 Antibodies:
[0097] No significant change in GAD65Ab levels (expressed as U/ml) was found in the placebo or 4 μg group. Levels in the 20 μg dose group did not change during the first 4 weeks, however, between 8 and 24 weeks ⅞ (88%) patients showed a decline. Similarly, in the 100 μg dose group there was a decline in 8/9 (89%) patients despite an increase in three of these patients between 4 and 24 weeks. All eight patients in the 500 μg group developed either an early increase before week 4 or a gradual increase after additional boost injections during the 24 weeks, and showed between a 2.1-fold and 22.1-fold maximum increase in GAD65Ab levels.
[0098] Measurement of GAD65Ab is currently the most robust marker used to identify autoimmune diabetes and predict future insulin requirement in LADA. Their clear induction in the top dose group (p=0.001) support the impact of Diamyd™ treatment on the immune system. The decrease in GAD65Ab levels associated with efficacy at the 20 μg dose level may reflect a preservation of beta cells. This may be rationalized by reduced beta cell destruction lowering the amount of GAD65 released and presented to the immune system, resulting in reduced quantities of antibodies produced. A direct down-modulatory effect on B lymphocyte activity is also possible.
[0000] T Lymphocytes:
[0099] There were no differences between the groups in the majority of peripheral T lymphocyte subsets (CD3+, CD4+, CD8+, NK) analysed on day 1 and during the 24 weeks of observation. In contrast however, a statistically significant increase over time was found for the ratio of a particular T cell subset in patients receiving 20 μg Diamyd™ (p=0.012), and this increase was different from that in the placebo group (p=0.03). This T lymphocyte subset (with the surface markers CD4+ and CD25+) are currently implicated in regulating the activity of other T cells, and their involvement in inhibition of autoimmunity has also been demonstrated in animal models.
[0100] A positive correlation between the change in this CD4 + CD25 + /CD4 + CD25 − T cell ratio and change in fasting C-peptide (r=0.51; p<0.005) was found, supporting the increase in C-peptide being related to an increase in this T cell ratio. This correlation was also found for meal-stimulated C-peptide (r=0.34; p<0.05).
[0101] In view of the critical involvement of GAD65-specific T helper and cytotoxic T cells in the autoimmune destructive process leading to insulin dependence, positive evidence for the induction of a different T cell subset, capable of downregulating autoimmunity, is considered to be an important study finding.
CONCLUSIONS
[0102] The foregoing study supports the following conclusions:
[0103] Statistically significant increases in fasting and meal-stimulated C-peptide levels were apparent in the 20 μg dose, and these positive effects were confirmed when these data were normalised against fasting blood glucose. The positive effects was maintained throughout an 18 months follow up period.
[0104] Positive evidence for immunomodulation was provided by analysis of T cell subsets. This strongly indicates that two injections of Diamyd™ effectively increases C-peptide production as a result of specific down regulation of beta cell inflammation by activated regulatory T cells.
[0105] The Diamyd™ treatment raises no safety concerns. In particular, GAD65Ab levels, even after re-boosts at the top dose (4×500 μg), do not support the likelihood of Diamyd™ treatment causing neurological disease (e.g. Stiff Man).
[0106] At two years, 7/14 patients in a control group (a “no-effect” 4 μg dose group+placebo) versus ⅛ of patients receiving the effective 20 μg dose became insulin dependent.
[0107] Positive evidence for safety and efficacy together with the provision of insights into the mechanism of action of the treatment therefore strongly support the potential for Diamyd™ as a therapy for autoimmune diabetes.
[0108] All publications and patents mentioned herein are hereby incorporated by reference to the same extent as if each individual publication or patent was specifically and individually indicated to be incorporated by reference. Related Provisional Patent Application Ser. No. 60/478,392 and the corresponding U.S. patent application based thereupon is also hereby incorporated herein by reference. Many variations of the present invention within the scope of the appended claims will be apparent to those skilled in the art once the principles described herein are understood.
REFERENCES
[0000]
1. Gepts W. Pathologic anatomy of the pancreas in juvenile diabetes mellitus. Diabetes 1965; 14:619-633.
2. Leslie R D, Atkinson M A, Notkins A L. Autoantigens IA-2 and GAD in Type I (insulin-dependent) diabetes. Diabetologia 1999; 42:3-14.
3. Verge C F, Gianani R, Kawasaki E, et al. Number of autoantibodies (against insulin, GAD or ICA512/IA2) rather than particular autoantibody specificities determine risk of type I diabetes. J Autoimmun 1996; 9:379-383.
4. Graham J, Hagopian W A, Kockum I, et al. Genetic effects on age-dependent onset and islet cell autoantibody markers in type 1 diabetes. Diabetes 2002; 51:1346-1355.
5. Zimmet P Z, Tuomi T, Mackay IR, et al. Latent autoimmune diabetes mellitus in adults (LADA): The role of antibodies to glutamic acid decarboxylase in diagnosis and prediction of insulin dependency. Diabetic Med 1994; 11:299-303.
6. Turner R, Stratton I, Horton V, et al. UKPDS 25: autoantibodies to islet-cell cytoplasm and glutamic acid decarboxylase for prediction of insulin requirement in type 2 diabetes. UK Prospective Diabetes Study (UKPDS). Lancet 1997; 350:1288-1293.
7. Tuomi T, Carlsson, A Li H, et al. Clinical and genetic characteristics of type 2 diabetes with and without GAD antibodies. Diabetes 1999; 48:150-157.
8. Kaufman D L, Clare-Salzler M, Tian J, et al. Spontaneous loss of T-cell tolerance to glutamic acid decarboxylase in murine insulin-dependent diabetes. Nature 1993; 366:69-72.
9. Tisch R, Yang X D, Singer S M, Liblau R S, Fugger L, McDevitt H O. Immune response to glutamic acid decarboxylase correlates with insulitis in non-obese diabetic mice. Nature 1993; 366:72-75.
10. Pleau J M, Fernandez-Saravia F, Esling A, Homo-Delarche F, Dardenne M. Prevention of autoimmune diabetes in nonobese diabetic female mice by treatment with recombinant glutamic acid decarboxylase (GAD65). Clin Immunol Immunopathol. 1995; 76: 90-95.
[0119] 11. Petersen J S, Karisen A E, Markholst H, Worsaae A, Dyrberg T, Michelsen B. Neonatal tolerization with glutamic acid decarboxylase but not with bovine serum albumin delays the onset of diabetes in NOD mice. Diabetes 1994; 43:1478-1484.
12.Tian J Atkinson M A, Clare-Salzler M, Herschenfeld A, Forsthuber T, Lehmann P V, Kaufman D L. Nasal administration of glutamate decarboxylase (GAD65) peptides induces Th2 responses and prevents murine insulin-dependent diabetes. J Exp Med 1996a; 183:1-7. 13. Tian J, Clare-Salzler M, Herschenfeld A, et al. Modulating autoimmune responses to GAD inhibits disease progression and prolongs islet graft survival in diabetes-prone mice. Nat Med. 1996b; 2:1348-1353. 14.Tisch R, Liblau R S, Yang X D, Liblau P, McDevitt H O. Induction of GAD65-specific regulatory T-cells inhibits ongoing autoimmune diabetes in nonobese diabetic mice. Diabetes 1998; 47:894-899. 15. Lethagen ÅL, Ericsson U B, Hallengren B, Groop L, Tuomi T. Glutamic acid decarboxylase antibody positivity is associated with an impaired insulin response to glucose and arginine in nondiabetic patients with autoimmune thyroiditis. J Clin Endocrinol Metab 2002; 87:1177-1183. 16. Bingley P J, Bonifacio E, Mueller P W. Diabetes antibody standardization program: first assay proficiency evaluation. Diabetes 2003; 52:1128-1136. 17. Brown P, Rothwell J C, Marsden C D. The stiff leg syndrome. J Neurol Neurosurg Psychiatry. 1997; 62: 31-37. 18. Barker R A, Revesz T, Thom M, Marsden C D, Brown P. Review of 23 patients affected by the stiff man syndrome: clinical subdivision into stiff trunk (man) syndrome, stiff limb syndrome, and progressive encephalomyelitis with rigidity. J Neurol Neurosurg Psychiatry 1998; 65: 663-640. 19. Smith G E, Summers M D, Fraser M J. Production of human beta interferon in insect cells infected with baculovirus expression vector. Mol Cell Biol. 1983; 3:2156-2165. 20. Shevach E M. CD4+CD25+ suppressor T cells: more questions than answers. Nat Rev Immunol 2002; 2:389-400. 21. Sakaguchi S. Regulatory T cells: key controllers of immunologic self-tolerance. Cell 2000; 101:455-458. 22.Shevach E M, McHugh R S, Piccirillo CALIFORNIA, Thornton A M. Control of T-cell activation by CD4+CD25+ suppressor T cells. Immunol Rev 2001; 182:58-67. 23.Jonuleit H, Schmitt E, Stassen M, Tuettenberg A, Knop J, Enk A H. Identification and functional characterization of human CD4(+)Cd24(+) T cells with regulatory properties isolated from peripheral blood. J Exp Med 2001; 193:1285-1294. 24. Stephens L A, Mottet C, Mason D, Powrie F. Human CD4(+)CD25(+) thymocytes and peripheral T cells have immune suppressive activity in vitro. Eur J Immunol 2001; 31:1247-1254.
[0133] The preferred embodiment herein disclosed is not intended to be exhaustive or to unnecessarily limit the scope of the invention. The preferred embodiments were chosen and described in order to explain the principles of the present invention so that others skilled in the art may practice the invention. Having shown and described preferred embodiments of the present invention, those skilled in the art will realize that many variations and modifications may be made to affect the described invention. Many of those variations and modifications will provide the same result and fall within the spirit of the claimed invention. It is the intention, therefore, to limit the invention only as indicated by the scope of the claims. | The present invention regards methods and formulations for the treatment of diabetes and the prevention of autoimmune diabetes. The invention includes the administration of human recombinant GAD65 protein in a pharmaceutically acceptable adjuvant. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority from provisional application Ser. No. 60/068,463 filed Dec. 22, 1997 and entitled REMOVABLE DOCTOR BLADE HOLDER.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to doctors used, in papermaking machines, and is concerned in particular with the provision of a blade holder which is readily separable from the doctor back and removable from the papermaking machine for cleaning, inspection and repair.
2. Description of the Prior Art
The main components of a doctor system include the doctor blade, the blade holder, the doctor back and the loading mechanism. The doctor blade keeps the roll clean and/or sheds the sheet. It must be perfectly flat, straight and parallel, and its composition must be compatible with the roll to be doctored.
The blade holder exerts a uniform, designated load pressure on the blade. It holds the blade firmly against the roll, accommodates roll irregularities and, within limits, compensates for thermal expansion.
The doctor back is in essence the backbone of the doctor. It serves as the support structure for the blade holder. The loading mechanism pivots the doctor back to load the doctor blade against the roll.
Doctor blade holder designs used in recent years are more complex and have more components than the simpler blade holders used in the past. As a result, the more recent holder designs require more routine cleaning and maintenance. The doctor blade holders are normally mounted to the doctor back rigidly with a series of fasteners. Maintenance and cleaning of the blade holder can take place while the doctor remains in the machine but only in installations where the holder is accessible. However, in many cases, papermachine framework or other equipment prevents access to the blade holder while it is in the papermachine. In these cases, the complete doctor structure including the doctor back and attached holder must be removed from the papermachine to perform any cleaning or maintenance work. This task involves removing heavy equipment which requires extensive manpower and machine downtime. After making the necessary repairs, the entire doctor assembly must be re-installed in the papermachine, consuming more valuable manpower and time. In addition to the re-installation, the doctor must be re-aligned to the roll surface for optimum doctor performance.
SUMMARY OF THE INVENTION
The present invention avoids or at least significantly minimizes the above mentioned problems by providing a doctor blade holder which is readily separable from the supporting doctor back. Thus, while the doctor back remains undisturbed in the papermachine, operating personnel can remove the blade holder for cleaning and maintenance. Thereafter, the blade holder is returned to its operative position on the doctor back and locked in place. Certain embodiments of the invention further include the provision of a releasable clamping mechanism for clamping the blade holder in place on the doctor back during papermachine operation.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objectives, features and advantages of the present invention will be described in greater detail with reference to the accompanying drawings; wherein:
FIG. 1 is a side view of a doctor assembly in accordance with the present invention;
FIG. 2 is an enlarged view of the doctor blade holder shown in FIG. 1;
FIG. 3A is a sectional view taken along line 3 A— 3 A of FIG. 2 showing the blade holder in its operative position clamped to the doctor back;
FIG. 3B is a view similar to FIG. 3A showing the blade holder unclamped from the doctor back;
FIG. 3C is a horizontal sectional view taken along line 3 C— 3 C of FIG. 3A;
FIG. 4 is a view similar to FIG. 2 showing an alternative embodiment of a blade holder in accordance with the present invention;
FIG. 5 is a horizontal sectional view taken along line 5 — 5 of FIG. 4;
FIG. 6 illustrates another embodiment of a blade holder in accordance with the present invention;
FIG. 7 is a horizontal sectional view taken along line 7 — 7 of FIG. 6;
FIG. 8 illustrates another embodiment of a blade holder in accordance with the present invention;
FIG. 9 is a perspective view of one of the dovetail washers employed in the arrangement shown in FIG. 8;
FIG. 10 illustrates still another embodiment of a blade holder in accordance with the present invention;
FIG. 11 is a perspective view of one of the stepped washers used in the arrangement shown in FIG. 10;
FIG. 12 is a perspective view showing a further modification to blade holders embodying the concepts of the present invention; and
FIG. 13 is a partial plan view of the blade holder and doctor back at one side of the papermachine.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
With reference initially to FIG. 1, a doctor assembly in accordance with the present invention is generally depicted at 10 adjacent to a papermachine roll 12 . Roll 12 is driven by conventional means (not shown) for rotation about an axis A, extending in the cross-machine direction. The doctor assembly includes a doctor blade 14 , a blade holder 16 , a doctor back 18 , and a loading mechanism 20 . The doctor back is mounted on the papermachine frame for pivotal movement about an axis A 2 extending in the cross-machine direction parallel to the rotational axis A 1 , of roll 12 . The loading mechanism 20 includes a piston-cylinder unit 22 acting through lever arm 24 to pivot the doctor back 18 about its axis A 2 in order to load the doctor blade 14 against the surface of the roll 12 .
With reference additionally to FIGS. 2 and 3 A- 3 C, it will be seen that the blade holder 16 includes a tray 26 with upstanding brackets 28 located between an unloading tube 30 and a loading tube 32 . A top pressure plate 34 overlies the tubes 30 , 32 and has depending brackets 36 which are connected to the brackets 28 by a rod 38 for pivotal movement about a third axis A 3 parallel to axes A 1 , and A 2 .
Fingers 40 cooperate with the underside of the top pressure plate 34 to retain the doctor blade 14 in its forwardly extending position. The tubes 30 , 32 are fluid actuated, with tube 32 serving to coact with the force being applied by the loading mechanism 20 to apply the blade 14 to the surface of the roll 12 . Tube 30 serves to unload the blade from the roll surface, in addition to acting as a front seal.
A pair of L-shaped confronting mounting strips 42 a , 42 b are secured to the underside of the tray 26 . The mounting strips have horizontal ledges 44 a , 44 b spaced one from the other to define a continuous slot 46 communicating with an interior recess 47 .
A shelf 50 extends forwardly from and forms an integral part of the doctor back 18 . Shoulder screws 52 are threaded into the shelf 50 at spaced locations along the length of the slot 46 . A locking strip 54 in interposed between the ledges 44 a , 44 b and the heads of the shoulder screws 52 . The locking strip is slotted as at 56 to accommodate the shoulder screws, and the slots 56 are partially bordered by resilient tabs 58 which are bent upwardly out of the lane of the locking strip.
The locking strip 54 is slidable longitudinally with respect to the shelf 50 of the doctor back and the mounting strips 42 a , 42 b on the underside of the tray 26 . When in the locked position as shown in FIGS. 3A and 3C, the tabs 58 are deflected downwardly by the heads of the shoulder screws 52 into the plane of the strip 54 , thereby exerting a downward force which clamps the ledges 44 a , 44 b against the shelf 50 , thus fixing the doctor holder 16 in its operative position on the doctor back 18 . As can be best seen in FIG. 3A, a pin 60 or the like at one side of the papermachine is employed to releasably fix the locking strip 54 in its locked position.
When it becomes necessary to clean or maintain the blade holder, the pin 60 is removed and the locking strip 54 is shifted to its unlocked position as shown in FIG. 3 B. This relieves the clamping force exerted by the resilient tabs 58 , thus allowing the blade holder and doctor blade to be extracted longitudinally as a unit out of the papermachine. After cleaning and maintenance, the blade holder is longitudinally reinserted into the papermachine, and the clamping strip returned to its locked position.
An alternative embodiment of the invention is depicted in FIGS. 4 and 5, where a mounting strip 62 a is secured to the underside of the tray 26 . A second mounting strip 62 b is connected to strip 62 a by means of shoulder screws 64 extending through angled slots 66 . The strips 62 a , 62 b coact to define a dovetailed slot 68 for receiving a dovetail strip 70 secured to the doctor back shelf 50 by screws 72 . Longitudinal movement of the strip 62 b in direction A will urge it laterally against the dovetail strip 70 , thus clamping the blade holder in place.
Longitudinal movement of the strip 62 b in the opposite direction B will shift the strip 62 b laterally away from strip 70 , thus freeing the doctor holder for removal from the doctor back. If the strip 62 b is only shifted slightly laterally, the blade holder can be slid longitudinally into and out of its operative position, whereas a more pronounced lateral shifting of the strip will permit the blade holder to be lifted from and lowered onto the doctor back.
In the embodiment shown in FIGS. 6 and 7, a male dovetail strip 74 is secured to the underside of the tray 26 and a female dovetail strip 76 is secured to the doctor back shelf 50 . A set screw 78 at one side of the papermaking machine serves to fix male dovetail the strip 74 against sliding movement relative to the female dovetail strip 76 . When the screw 78 is backed off as shown in FIG. 7, the blade holder is free to slide longitudinally into and out of its operative position on the doctor back.
In the embodiment shown in FIGS. 8 and 9, a female dovetail strip 80 is secured to the underside of the tray 26 , and frustoconical dovetail washers 82 are secured to and spaced along the length of the doctor back shelf 50 .
In FIGS. 10 and 11, stepped washers 84 are secured at spaced locations along the underside of the tray 26 , and a mounting strip 86 is secured to the doctor back shelf 50 . The mounting strip 86 has an undercut channel 88 along which the stepped washers slide during longitudinal extraction and insertion of the blade holder.
FIG. 12 illustrates another embodiment where a mounting strip 90 with an undercut channel 92 is secured to the doctor back shelf 50 . The channel 92 is interrupted as at 94 at spaced locations along its length. This allows either the stepped washers 84 of FIGS. 11 or 12 stepped strip segments 96 which are secured to the underside of the blade holder tray 26 to slide along the channel 92 to positions at which they may exit via the interrupted sections 94 either laterally in direction A or vertically in direction B.
In the embodiments shown in FIGS. 8 to 12 , a locking means of some type is provided at one side of the machine to prevent removal of the blade holder from the doctor back during operation of the papermachine. As shown in FIG. 13, locking can be achieved by providing a bracket 98 on the tray 26 at one side of the papermachine which is detachably connected to the doctor back shelf 50 by a pin 100 or the like.
In light of the foregoing, it will now be appreciated by those skilled in the art that the present invention provides for ready separation of the doctor blade holder from the doctor back for removal from the papermachine. The embodiments illustrated in FIGS. 1-5 provide means for securely clamping the blade holder to the doctor back during operation of the papermachine. Other embodiments as illustrated in FIGS. 6-13 lock the blade holder in its operative position, but do not exert additional clamping forces. All arrangements are advantageous in that removability of the blade holder provides maintenance personnel with the opportunity to clean and perform maintenance outside of the papermachine, without disturbing the doctor back. | An apparatus for doctoring a roll in a paper machine, comprising a doctor blade and an integral blade holder including a support tray carrying fluid actuated tubes for applying the doctor blade to the roll. The blade holder is removably mounted on and releasably secured to the doctor back. | 3 |
RELATED APPLICATIONS
There are currently no co-pending applications.
FIELD OF THE INVENTION
The presently disclosed subject matter is directed to plumbing devices. More particularly, the present invention relates to sanitary plumbing vent line caps.
BACKGROUND OF THE INVENTION
Over the last one hundred twenty-five years (125 y.) or so plumbing has developed into a modern engineering marvel. American cities, suburbs and small towns have implemented a maze of plumbing pipes and pumps that both supply users with potable water from water sources and dispose of water borne waste into sewage systems.
The plumbing that removes water borne waste is commonly referred to as the drain-waste-vent (DWV) or sanitary piping system. The sanitary piping system removes sewage and greywater waste from a house or other building. Such waste is produced at toilets, sinks and showers. To prevent the unpleasant smell of sewer gas each sanitary piping fixture is supplied with a water trap, which is a section of pipe, usually containing a “U”-shaped trap filled with water. On one (1) side of the “U” shape traps are waste lines that run to the sewer system while on the other side is living or working spaces. Ideally the water in the “U” shape traps block sewer gas from seeping into the living spaces.
While sanitary piping systems work very well, they do have problems. Sewer gases can build up rather high pressures due to biodegrading sewer matter and other causes. Such pressure can cause sewer gases to escape back through the “U” shape traps. This is easily prevented by simply venting the sanitary piping system to atmospheric pressure using a vent line. A common sight on the roof of almost every home or building is the sanitary piping system vent line. Such vent lines release pressure build-up in the sanitary piping system which aids sewage transfer.
Properly maintained vent lines work very well. However, since the interior of the pipe is completely open to the environment, foreign objects or materials can easily enter. Items such as twigs, leaves, dirt, trash, and the like can fall or be blown inside, while birds, small animals, and insects can fly, crawl, or become trapped inside. Such materials can accumulate within the vent line, causing it to cease operating properly in that air does not freely enter and leave the vent line. This can result in piping backups and flooding. When such occurs the most realistic fix is to go to the roof and remove objects and blockages. A most unpleasant and dangerous task.
Accordingly, there exists a need for a means by which foreign material can be kept out of sanitary pipe vents in an effort to eliminate the problems as described above. Beneficially such a means would be easy to attach using common tools and fasteners and would allow air to readily enter the vent line. Even more beneficially that means would be easily removed to allow access to the vent line if required or if modifications are needed.
SUMMARY OF THE INVENTION
The principles of the present invention provide for vent line caps that keep foreign materials out of vent lines while still allowing air to readily enter and leave the line. Such vent caps are easily attacked using common tools and fasteners and are easily removed if access to the vent line is required or if modifications are needed.
A vent line cap that is in accord with the present invention includes a shroud assembly having an open-bottomed conical side and a generally circular top. The vent line cap further includes a substantially flat strap clamp and an inverted “U”-shaped support bracket having two (2) side legs, each with a bottom strap hook, and an upper horizontal leg that spans between the side legs. The top attaches to the upper horizontal leg while the bottom strap hooks attach to the strap clamp. Beneficially, each strap hook is a “U”-shaped appendage having a narrow vertical slot that is dimensioned to receive and close on the strap clamp as well as a fastener closing each strap hook around the strap clamp to form a rigid union.
The vent line cap preferably includes a strap clamp having an integral screw-type tensioner mechanism that interacts with a plurality of parallel apertures. Ideally the screw-type tensioner mechanism can be tightened or released using a common hand tool such as a screwdriver, a nut driver, a wrench, a crescent wrench, a lock wrench or pliers.
To properly mount the vent line cap on the top of a vent line, the two (2) side legs each include a horizontally protruding stop. In practice the shroud assembly is comprised of molded plastic or a corrosion resistant metal. A top fastener is used to connect the top to the upper horizontal leg. Because of mounting stress the top fastener should include a washer.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages and features of the present invention will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which:
FIG. 1 is an environmental view of a vent line cap 10 that is in accord with the preferred embodiment of the present invention;
FIG. 2 is a front perspective view of the vent line cap 10 shown in FIG. 1 ; and,
FIG. 3 is an upward-looking view of the vent line cap 10 shown in FIGS. 1 and 2 .
DESCRIPTIVE KEY
10 vent line cap
20 shroud assembly
22 side
24 top
50 strap clamp
52 tensioner mechanism
54 aperture
70 support bracket
72 strap hook
73 side leg
74 stop
75 upper horizontal leg
90 first fastener
92 second fastener
94 washer
100 building structure
105 vent line
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The best mode for carrying out the invention is presented in terms of its preferred embodiment, herein depicted within FIGS. 1 through 3 . However, the invention is not limited to the described embodiment and a person skilled in the art will appreciate that many other embodiments of the invention are possible without deviating from the basic concept of the invention, and that any such work around will also fall under scope of this invention. It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope.
The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items.
The principles of the invention provide for a preferred embodiment vent line cap 10 which protects existing sanitary plumbing vent lines from debris while allowing proper operation and easy installation and removal. FIG. 1 shows an environmental view of the vent line cap 10 . The vent line cap 10 is placed at the open end of an existing vent line 105 , which will usually be near where the vent line 105 exits the roof of a building 100 , such as a house, an apartment building, a commercial building, or most other buildings having plumbing. In practice, the vent line cap 10 will be made available in a variety of diameters to properly mate with the outer diameters of various standard vent lines 105 .
As shown in FIG. 1 the vent line cap 10 includes a molded shroud assembly 20 and a substantially flat strap clamp 50 that encircles the vent line 105 . The strap clamp 50 is used to attach the vent line cap 10 to the vent line 105 , beneficially using only common tools and such that the vent line cap 10 is rigidly fixed to the vent line 105 , but readily removed if desired. The shroud assembly 20 covers the vent line 105 opening, preventing foreign materials such as twigs, leaves, small animals, birds, or the like from gaining entrance to the vent line 105 and subjacent plumbing while still allowing air to freely enter or exit the vent line 105 .
FIG. 2 provides a front perspective view of the vent line cap 10 . The vent line cap 10 includes the shroud assembly 20 , the strap clamp 50 , and a support bracket 70 . The shroud assembly 20 has an open-bottomed, cone-segment-shaped cross-section that is formed by an outward flaring side 22 and a generally circular top 24 . The top 24 attaches to the top part of the support bracket 70 as described subsequently. Beneficially the shroud assembly 20 is comprised of a molded plastic such as polyvinyl chloride (PVC), fiberglass, a composite plastic, or alternately a metal such as painted, galvanized, or otherwise plated steel, stainless steel, or another corrosion resistant metal. Since the vent line cap 10 is envisioned as being available in a plurality of diameters to mate with different sized vent lines 105 , the shroud assembly 20 , strap clamp 50 , and support bracket 70 should be appropriately dimensioned.
Still referring to FIG. 2 the support bracket 70 is an inverted “U”-shaped unitary structure preferably made from formed, molded, or extruded flat stock material about one-half inch (½ in.) wide. This will provide the required structural strength to withstand high winds and other environmental stresses that the vent line cap 10 may experience. The support bracket 70 has two (2) integral strap hooks 72 that are located at the bottom ends of two (2) side legs 73 of the support bracket 70 . Each strap hook 72 is formed into a “U”-shaped appendage having a narrow vertical slot that is dimensioned to receive flat sections of the strap clamp 50 . When the strap clamp 50 is in the strap hooks 72 those hooks are closed around the strap clamp 50 using first fasteners 90 such as a rivet, screw, bolt, or the like so as to form a relatively rigid union.
The support bracket 70 further comprises two opposing integral stops 74 that protrude inward from intermediate positions of the two side legs 73 . The stops 74 are horizontal appendages approximately one inch (1 in.) in length configured to rest on the top of the vent line 105 so as to vertically position the vent line cap 10 on the vent line 105 .
The two (2) side legs 73 continue past the stops 74 to an upper horizontal leg 75 that connects to the two (2) side legs 73 , thus completing the inverted “U” shape of the support bracket 70 . The top 24 of the shroud assembly 20 is fastened at the center of the upper horizontal leg 75 using at least one (1) second fastener 92 having a washer 94 . The second fastener 92 is envisioned as being a rivet, screw, bolt, or the like, while the support bracket 70 is envisioned as being a rugged corrosion resistant material such as stainless steel, composite plastic, or an equivalent material capable of withstanding environmental stresses encountered on a building 100 roof.
FIG. 3 presents an upward-looking view of the vent line cap 10 . The strap clamp 50 is routed through the strap hooks 72 of the strap bracket 70 . This forms a guided circular clamp suitable for mating with the top of the vent line 105 . With the strap clamp 50 routed through the strap hooks 72 the strap clamp 50 can be tightened using a conventional integral screw-type tensioner mechanism 52 . The tensioner mechanism 52 engages and works in conjunction with a plurality of parallel vertical apertures 54 formed in the strap clamp 50 to enable tightening around the vent line 105 using a common screw or nut driver.
It is envisioned that many other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention. While only one particular configuration is shown and described it is for purposes of clarity and disclosure and not by way of limitation of scope.
The preferred embodiment of the present invention can be utilized by the common user in a simple and effortless manner with little or no training. After initial purchase or acquisition of the vent line cap 10 it would be installed as suggested in FIG. 1 . The method of installing and utilizing the vent line cap 10 may be achieved by performing the following steps: procuring a model of the vent line cap 10 having shroud assembly 20 , strap clamp 50 , and support bracket 70 which provide an inner diameter suitable for fitting over the outer diameter of an existing vent line 105 ; loosening the tensioner mechanism 52 using a common driver, if needed; inserting the strap clamp 50 over the end portion of the vent line 105 until the stops 74 of the support bracket 70 contact the top of the vent line 105 ; tightening the strap clamp 50 around the vent line 105 by rotating the tensioner mechanism 52 to obtain a tight fit with the vent line 105 ; and, benefiting from prevention of foreign material such as twigs or leaves, from entering the vent line 105 while using the vent line cap 10 .
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention and method of use to the precise forms disclosed. Obviously many modifications and variations are possible in light of the above teaching. The embodiment was chosen and described in order to best explain the principles of the invention and its practical application, and to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions or substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but is intended to cover the application or implementation without departing from the spirit or scope of the claims of the present invention. | A protective vent line cap for protecting sanitary plumbing vent lines is described. The vent line cap includes an open bottom conically flared shroud that attaches to the vent line using a mounting strap having an adjustable strap clamp fastener and a mounting bracket. The mounting bracket is fastened at its top to the shroud and at the bottom to the strap clamp. The vent line cap is designed to be easily installed and removed using common hand tools. The vent line cap prevents foreign material from entering the vent line and subjacent plumbing while still allowing air to flow from the vent line as well as preventing rain water from entering sewer system. | 4 |
CROSS-REFERENCE TO A RELATED APPLICATION
This application is a continuation-in-part of application Ser. No. 825,096 filed Jan. 31, 1986 (abandoned).
BACKGROUND OF THE INVENTION
The present invention relates to the generation of electric energy in general, and more particularly to a method of and a device for recovering heat energy of hot raw gas generated in a coal gasification arrangement of a combined gas turbine and steam turbine electric power generating plant.
There are already known various constructions of electric power generating plants of the above-mentioned type, in which the finely granular to pulverulent coal being used as a fuel is converted in the coal gasification arrangement at a pressure exceeding 1 bar and at a temperature in excess of 1000° C. to a partial oxidation gas having combustible components
consisting essentially of CO and H 2 and the thus obtained partial oxidation or raw gas is cooled in a waste-heat recovery boiler with simultaneous generation of steam, subsequently purified by removing particulate materials therefrom and by de-sulfurizing the same, and the thus purified gas is then combusted in a combustion chamber with attendant production of a hot combustion gas which is supplied to the gas turbine arrangement of the electric power generating plant, while the steam generated in the waste-heat recovery boiler is supplied, together with steam generated in a waste-heat recovery steam generator associated with the gas turbine arrangement, to the steam turbine arrangement.
Arrangements of the above type and methods performed thereby are already known in a number of different variations from a multitude of publications. These methods have recently gained an increased importance in view of the increasing concern for environmental protection and the discussions and legislative actions on this subject. In contradistinction to the currently predominating methods of generating electric energy by combusting fossil fuels, particularly coal, in accordance with which the fossil fuels which serve as energy sources are burned below steam-generating boilers and the steam generated in this manner is caused to expand in steam turbines for the purpose of generating electric current, the methods here under consideration are characterized by a considerably improved environmental impact. While the sulfur compounds contained in coal or other fossil fuels are converted during the burning of such fuels into sulfur dioxide which can be removed from the gaseous combustion products of conventional electric power generating plants only with a considerable effort and at a substantial cost, the sulfur compounds contained in the respective fuel are not converted into sulfur dioxide during the fuel gasification that is performed upstream of the power generating plant; rather, such compounds are at least predominantly converted into hydrogen sulfide. The latter can then be relatively easily removed from the produced raw gas by suitable physically or chemically acting means and scrubbing processes, so that the produced gas can be supplied to the electric power generating plant virtually free of sulfur and its compounds and an adverse environmental impact otherwise constituted by the discharged sulfur compounds is avoided.
During the performance of a method of the initially mentioned kind, the economy of the electric current generation depends very heavily on the utilization of the total available sensible heat energy, which must be as extensive as possible. In this connection, it is especially to be taken into consideration that, in accordance with the current state of the art, the steam turbine process has a lower efficiency than the gas turbine process. Therefore, it is important to assure that as great a proportion of the total available sensible heat energy be supplied to the gas turbine and, in this manner, the overall efficiency of the electric current generation process is improved.
In this connection, considerations on how to be able to transfer an as large as possible proportion of the sensible heat of the hot raw gas emerging from the coal gasification arrangement to the cold gas, which is supplied to the combustion chamber of the gas turbine and which has been previously purified by removal of particulate materials therefrom and by de-sulfurization, are constantly gaining in importance. Such a heat exchange process does not, in principle, create any problems as far as the purified gas is concerned, and various technical solutions have become known and have proven themselves in this context. In contradistinction thereto, however, the hot raw gas emerging from the coal gasification arrangement contains, in addition to fly ash or other entrained particles, other components which condense or precipitate from the raw gas under the given operating conditions, which results in the growth of deposits or encrustations and in other contamination or soiling of the surfaces of the heat exchanger which come into contact with the raw gas. The formation of such deposits can eventually result in a complete clogging of the raw-gas side of the heat exchanger and, of course, a correspondingly reduced effectiveness of the heat-exchange process is a direct result thereof. Experiments have shown that this problem cannot be satisfactorily solved in the long run even by the inclusion of particulate material removing arrangements upstream of the heat exchanger. Even the use of two separate heat exchangers, of which either one is in operation at a given time while the respectively other is being cleaned, does not present a practical solution to this problem, because of the high equipment and operation costs connected therewith. Finally, it is also not possible or not feasible to provide for the cleaning of the heat exchange surfaces during the continuous operation by the incorporation of cleaning apparatus in the known constructions of gas/gas heat exchangers, since no technically usable solution of this problem has been found so far, which solution would simultaneously provide for the cleaning of the heat exchange surfaces and the extraction of the precipitated contaminants during the continuous operation of the heat exchanger.
SUMMARY OF THE INVENTION
Accordingly, it is a general object of the present invention to avoid the disadvantages of the prior art.
More particularly, it is an object of the present invention to develop a method of generating electric energy in a combined gas and steam turbine electric power generating plant with a preceding coal gasification arrangement, which method does not possess the disadvantages of the known methods of this kind.
Still another object of the present invention is so to devise the method of the type here under consideration as to improve the overall efficiency of the power plant.
It is yet another object of the present invention so to perform the above method as to obtain an optimum utilization of the sensible heat of the hot raw gas generated in the coal gasification arrangement.
An additional object of the present invention is to achieve, by resorting to the method of the present invention, an optimum utilization of the sensible heat of the raw gas for the powering of the gas turbine arrangement even when the coal gasification arrangement is being operated only under partial load conditions.
A concomitant object of the present invention is to provide an electric power generating plant of the above type which is especially suited for the performance of the aforementioned method.
An additional object of the present invention is so to construct the power plant of the above type as to be relatively simple in construction, inexpensive to manufacture, easy to use, and reliable in operation nevertheless.
In pursuance of these objects and others which will become apparent hereafter, one feature of the present invention resides in a method of generating energy in a combined gas and steam turbine power plant which includes a gas turbine including a combustion chamber and a steam turbine with a steam generator, comprising the steps of providing a coal gasification arrangement with a heat recovery boiler having a housing and a row gas/purified gas heat exchanger incorporated in the housing of said boiler; partially oxidizing finely granular to pulverulent coal in said coal gasification arrangement at a pressure exceeding 1 bar and at a temperature in excess of 1000° C. to obtain hot raw gas containing combustible components essentially
consisting of CO and H 2 ; cooling the hot raw gas in the heat recovery boiler; purifying the raw gas by removing particulate contaminants therefrom and by desulfurizing the same in a desulfurization unit; conveying the purified gas from said desulfurization unit to said heat exchanger and pre-heating the purified gas in said raw gas/purified gas heat exchanger to a temperature in the range between 300° and 500° C.; conveying the preheated purified gas to said combustion chamber and combusting the pre-heated purified gas in the combustion chamber to produce hot combustion gas for driving the gas turbine of said power plant; and supplying the steam generated in the heat recovery boiler to the steam turbine for driving the same.
A particular advantage of the method as described so far is that the overal efficiency and economy of the electric power generating plant is significantly improved as compared to those of the known power generating plants, owing to the fact that the sensible heat of the hot raw gas generated in the coal gasification arrangement is being utilized to the largest extent possible in the gas turbine arrangement because of the indirect transfer of this heat to the purified gas.
Inasmuch as waste-heat recovery boilers, because of their structural features and well as in view of the configuration of the pressure jacket and also the configuration and arrangement of the heating surfaces or elements, are well suited for an economical installation of cleaning apparatus therein, it is possible in accordance with the method of the present invention, in contradistinction to the known constructions of gas/gas heat exchangers, to remove contaminant deposits from the heat-exchange surfaces of the heat exchanger which come in contact with the raw gas during continuous operation by installing cleaning apparatus at relevant portions of the waste-heat recovery boiler, so that long-term uninterrupted operation of the plant is made possible. Thus, according to another aspect of the present invention, the inventive method includes the step of cleaning those heat-exchange surfaces of the raw gas/purified gas heat exchanger incorporated in the waste-heat recovery boiler which come into contact with the raw gas.
For the performance of the method according to the present invention, it is further advantageous when a waste-heat recovery boiler construction is used in which the boiler heating surfaces or elements which are arranged upstream of the raw gas/purified gas heat exchanger are so constructed that they are selectively switchable into their economy and saturated steam operating states. Then, the method of the present invention further includes the step of switching the boiler heating surfaces between their economy and saturated steam operation states. As a result of this construction, the raw gas temperature at the input of the raw gas/purified gas heat exchanger which is integrated into the waste-heat recovery boiler can be varied for adjusting the desired purified gas temperature at the outlet of the heat exchanger.
For the further optimization of the heat transfer to the purified gas, a steam-heated auxiliary heat exchanger can be arranged downstream of the waste-heat recovery boiler, and the purified gas is then caused to flow through this auxiliary heat exchanger before reaching the combustion chamber of the gas turbine. Herein, this auxiliary heat exchanger is being heated by the steam derived from the preceding waste-heat recovery boiler. In this connection, steam is being preferably used which has a temperature of between 525° and 540° C. and a pressure of 140 to 160 bar. Owing to this particular construction, it is possible to utilize an increased proportion of the sensible heat of the raw gas in the gas turbine even in extreme conditions of partial load operation of the coal gasification arrangement, that is when the amount of the sensible heat made available by the raw gas in the waste-heat recovery boiler is considerably lower than it is under normal operating conditions. Thus, another facet of the method of the present invention includes the performance of the step of additionally pre-heating the purified gas in an auxiliary heat exchanger by indirect heat exchange with steam derived from the waste-heat recovery boiler.
The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a block diagram of the electric power generation plant according to the present invention; and
FIG. 2 is a schematic, sectional view of a part of a pressure vessel for receiving hot raw gas from a coal gasification arrangement and enclosing a heat exchanger of this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring firstly to FIG. 1, reference numerals 1 to 4 identify four different mutually interconnected plant units of the overall plant for the generation of electric energy from coal particles. The units 2 to 4 are illustrated only in block form since they are of known constructions. The plant unit 1 incorporates a coal gasification arrangement of a conventional construction connected with a waste-heat recovery boiler 19 which by itself is also of a conventional construction, and a raw gas/clean gas heat exchanger 10 which according to the invention is integrated into the waste-heat recovery boiler, 19. The plant unit 1 further includes a raw gas cleaning facility of a known construction. The plant unit 2 incorporates all arrangements which are necessary for the de-sulfurization of the raw gas. The plant unit 3 includes arrangements for performing air decomposition, while the plant unit 4 is the electric power generating unit which includes respective gas and steam turbine arrangements.
Finely granular to pulverulent coal which is being used in this instance is introduced through a coal supply line 17 into the coal gasification arrangement of the plant unit 1, where it is gasified by partial oxidation with oxygen at a pressure exceeding 1 bar and at a temperature in excess of 1000° C. The heat of reaction which becomes liberated during this partial oxidation process is being used or recovered in that the produced hot raw gas is conducted through the wasteheat recovery boiler 19 of the unit 1, to contact the raw gas/clean gas heat exchanger 10 incorporated in the boiler. Superheated steam having a pressure of up to 160 bar and a temperature of about 525° to 540° C. can be generated in the waste-heat recovery boiler, and this superheated steam is supplied through a steam pipeline 5 to the steam turbine arrangement of the electric power generating plant unit 4.
With reference to FIG. 2 which illustrates the plant unit 1 in greater detail, reference numeral 10 designates a raw gas/clean gas heat exchanger shown as a box in FIG. 1. Reference numeral 18 designates a pressure vessel in which a tubular pipe wall housing 19' of the heat recovery boiler 19 is placed. Raw gas under pressure generated in a non-illustrated coal gasification arrangement is supplied into the heat recovery boiler in the direction of arrow 17'. The pressure vessel 18 is formed so that a prevailing gasification pressure is maintained therein. The tubular pipe-wall housing 19' performs the heat recovery function of the boiler. Water is fed into the boiler housing 19' via conduit 8 as also shown in FIG. 1 while super heated steam leaves the boiler housing via line 5. The raw gas/clean gas heat exchanger 10 is inserted within the central part of the tubular boiler 19. The heat exchanger 10 is formed in the known fashion of two tubular coils. These tubular coils are loaded with purified gas which in the cold state enters the heat exchanger via line 6 and is discharged from heat exchanger 10 in the heated state via conduit or line 13. The external surfaces of the tubular coils of the heat exchanger 10 are rinsed with hot raw gas which flows downwardly so that a part of its sensible heat is transmitted to the clean gas. Heating elements 20 of an auxiliary waste-heat boiler are further positioned in the tubular body 19 below the heat exchanger 10. An additional part of sensible heat of the raw gas can be used due to the heating surfaces 20 for the generation of saturated steam. The required water supply into the heating elements 20 is conducted via conduit 21 while saturated steam is discharged therefrom via line or conduit 22. The cooled raw gas flows downwardly from the boiler and enters a dust separator or cyclone 23 from which raw gas freed from dust and cooled, is discharged into conduit 12 and fed to further gas processing in unit 2, as shown in the block diagram of FIG. 1. Dust separated from the raw gas flows into a dust collecting container 24 from which it is continually or discontinually removed.
In order to avoid deposits on the tubular housing 19 a soot blower is provided between the pressure container 18 and the tubular housing 19. Furthermore, mechanical cleaning or knocking devices 26 are provided in the upper portion of the boiler. These tapping devices 26 act on the tubular housing 19 and raw gas/clean gas heat exchanger 10 and serve to clean respective tubular surfaces by knocking off deposited contaminants into the stream of raw gas.
FIG. 2 illustrates only the lower and middle parts of the boiler the non-shown upper part of which in principle corresponds to the shown lower part. This means that the pressure container 18 is respectively rounded and merges into the connection for the raw gas feeding.
FIG. 2 shows a preferred embodiment of the boiler. Other constructions can be used within the limits of the present invention.
Referring back to FIG. 1, it will be seen that the raw gas which is correspondingly cooled in the waste-heat recovery boiler and in the raw gas/clean gas heat exchanger 10, after its partial purification which involves the removal of fly ash or dust and possible also other pollutants therefrom, is conducted through the partially purified gas line 12 into the plant unit 2 where de-sulfurization of this partially purified gas takes place. The cold purified gas which is obtained in this manner is conducted, through a purified gas line 6, back into the raw gas/clean gas heat exchanger 10 where it is heated by indirect heat exchange with the hot raw gas to a temperature in the range essentially between 300° and 500° C. Finally, the heated purified gas is conducted through the heated purified gas conduit 13 into a steam-heated auxiliary heat exchanger 11 which is preferably being used during a partial load operation of the coal gasification arrangement.
Steam originating in the waste-heat recovery boiler is used for the heating of the auxiliary heat exchanger 11, the steam used for this purpose being branched off from the steam pipeline 5 into an auxiliary steam pipeline 15 leading to the auxiliary heat exchanger 11. Herein, the purified gas is preheated in all to a temperature of about 500° C. and is then supplied through a pre-heated gas conduit 14 into the electric energy generating plant unit 4. Simultaneously, nitrogen from the air decomposition plant unit 3 is being supplied through a conduit 7 to the electric energy generating plant unit 4 and is mixed with the pre-heated purified gas upstream of or in the combustion chamber of the gas turbine arrangement of the plant unit 4 in such an amount that the combustion gas produced in the combustion chamber can be supplied to the gas turbine arrangement of the plant unit 4 at a temperature of between 1100° and 1500° C.
As mentioned above, the final temperature of the purified gas can be varied within the aforementioned temperature range in that economy heating surface in the waste-heat recovery boiler are switched to saturated steam heating surfaces. A conduit 8 for the boiler feed water and a conduit 9 for the steam condensate from the auxiliary heat exchanger 11 constitute partial branches of the heat-conducting connection between the plant units 1 and 4. The air needed for the air decomposition is supplied to the plant unit 3 through a conduit 16.
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of arrangements differing from the types described above.
While the invention has been illustrated and described as embodied in a coal gasification electric power generating plant, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention. | In an electric energy generating plant including a coal gasification arrangement and a combined gas turbine and steam combine, hot raw gas generated in the gasification arrangement is fed via a heat-exchanging and dust separating unit into a desulfurization unit from which cool purified gas is discharged. The heat exchanging unit includes a tubular pressure resistant housing serving as a feeding passage for the hot raw gas and enclosing a coaxial arrangement of a tubular pipe-wall housing of a waste-heat recovery boiler, and pipe spirals of a raw gas/purified gas heat exchanger. The waste-heat recovery boiler delivers superheated steam to the steam turbine and the raw gas/purified gas heat exchanger delivers heated purified gas to the gas turbine. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates to the field of dentistry. More specifically, the present invention relates to a method and apparatus for assessing the periodontal health of an individual using ultra-sound imaging.
BACKGROUND
[0002] Periodontal disease (PD), which affects more than 60 million people, is the second most prevalent disease in the United States, yet less than one-fifth of Americans with periodontal disease receive treatment. Periodontal services require 150 million hours and $7 billion dollars annually. PD affects 80% of all adults and 90% of those between the ages of 55 and 64. It is estimated that 70 million adults suffer from some form of PD. Periodontal infections are now linked to cardiovascular disease, stroke, and diabetes making PD a serious health threat.
[0003] PD begins with a build up of plaque (which has bacteria in it) on a tooth. The bacteria in plaque attack the bone around the tooth, as well as the fibers (the periodontal ligament) that connect the tooth to the bone. As the fibers and bone are destroyed, a gingival pocket or space forms between the gum and the tooth—an ideal site for more plaque to build up. Left untreated, PD results in the destruction and recession of the periodontal ligament, which attaches the root of the tooth to the bone surface that makes up the interior of the tooth socket. The tooth attachments are destroyed in unpredictable site-specific pattern. Because public awareness of the disease is low and the early stages are painless, people generally don't floss that much, and as a result the disease progresses.
[0004] Unfortunately, because of the low awareness of the disease, it is generally not recognized until it has progressed to a significant degree. The treatment at this point, although effective, is uncomfortable, expensive, and often uncovered by insurance.
[0005] The accepted standard for measuring the progression of PD is to probe the gingival pocket to measure its depth and thereby measure the degree of recession of the periodontal ligament. The current gold standard for this measurement is a small ruler called a periodontal probe that is “poked” into the gum line to find and measure periodontal pockets and gum line detachments. The process is slow and painful, taking 10-15 minutes for some 180 measurements. Further, unless an automated recording system is used, the process requires the participation of two persons, one to take the measurements and a second to record the measurements. Recording of measurements is necessary to compare readings from one date to another to see if a pocket is breaking down. Because this is a tedious and painful process that is seldom done accurately or to completion, it is difficult to accurately identify and track the progress of the disease. The result is that the disease progresses insidiously and continually.
[0006] In addition to manual probing, another approach is disclosed in U.S. Pat. Ser. No. 5,755,571 to Companion. The probe disclosed in this patent uses intra-sulcular ultra-sound waves projected along the surface of the tooth for determining periodontal pocket depth. This method is less invasive with the mechanism, but injects a stream of water into the pocket to act as a transmission medium for ultra-sound waves. In addition to being a generally messy process, the injection of water into the root area of a tooth infected with PD can be the source of additional irritation of the area and discomfort to the patient. In addition, the water stream theoretically could mobilize the bacterium and cause cross contamination of sites. Further, the probe disclosed in Companion requires a fixed reference point, and uses the cemento-enamel junction (CEJ) as that reference point. The CEJ is the junction point between the enamel crown of a tooth and the cementum that makes up the root of the tooth. Establishing this reference point requires the use of an invasive probe that is incorporated with the ultra-sonic probe. Further, as disclosed in Companion, the CEJ is often difficult to locate or not present at all due to human variation and/or destruction of the CEJ.
[0007] A device known as the Florida probe uses a spring-loaded mechanism to detect the CEJ. Manual probing and the Florida probe are similar in that they invade the pocket to the base and make measurements from contact with the tissue at the bottom of the pocket. While considered to be superior to standard manual probing techniques, the Florida probe suffers from the same drawback as standard probing in that it is extremely invasive. In fact, the spring loaded mechanism of the Florida probe results in greater pressure being applied, and hence greater irritation to the gingival pocket. Further, the Florida probe suffers the same limitation as manual probing in that the presence of tartar in the pocket area may result in the determination of a false bottom for the pocket.
[0008] All of these methods approach the measurement of gingival pocket depth by varying levels of invasive measurement and are therefore likely to be uncomfortable for the patient and could prove cause for cross contamination.
[0009] U.S. Pat. Ser. No. 6,413,220 to Rose discloses a method and apparatus for using ultra-sonic waves for measuring the depth of a detachment between a tooth and its supporting tissue. Like the probe disclosed in Companion, the apparatus disclosed by Rose projects an intra-sulcular ultra-sound wave along the surface of a tooth (surface acoustic wave pulse) to determine pocket depth. The method and apparatus of Rose depend on achieving a particular critical angle of incidence between the tooth surface and the ultra-sonic probe. Therefore, repeatability of this method is highly dependent upon the skill of the operator.
[0010] Therefore, a need exists for a non-invasive method and apparatus for the identification and tracking of periodontal disease. Such a method would measure periodontal pocket depth non-invasively, and thereby enhance patient comfort. Therefore the method would reduce patient fears regarding examination of the gums and thereby make the public more likely to seek out the appropriate care and obtain early diagnosis and treatment. Such a method would further be easy to use, equivalent in complexity and time of use to current manual probes. Such a method would thereby offer repeatability, and the ability to track patient gum health, and given the new evidence of the relation of PD to systemic disease, make a serious improvement to public health.
SUMMARY OF THE INVENTION
[0011] The current invention uses a precise ultra-sonic probe to painlessly, non-invasively, and accurately measure the periodontal pockets. Many pockets can be done at once and automatically recorded to allow comparative analyses of data thereby detecting periodontal disease (PD) much earlier. The current invention thereby revolutionizes PD treatment by telling the dentist, doctor, and patient when and where to treat PD very early and very accurately. Further, because of public familiarity with other uses of ultra-sound, the current invention may lead to increased demand for services and thereby lead to a better understanding of PD on the part of the public.
[0012] The current invention achieves this by providing a method for determining the depth of a gingival pocket. The method comprises transmitting a transgingival ultra-sonic signal through the gum of an individual at the location of a gingival pocket and receiving at least one reflected ultra-sonic signal in a raw waveform. The raw waveform is processed into a processed waveform. The time of flight between transmission of the ultra-sonic signal and reception of the at least one reflected ultra-sonic signal is measured, wherein the depth of a gingival pocket is determined by the time elapsed between the transmission of the ultra-sonic signal and the reception of the at least one reflected ultra-sonic signal. The amplitude of the at least one reflected ultra-sonic signal is measured, wherein the density of a material from which a reflected ultra-sonic signal is received is determined by the amplitude of the reflected signal.
[0013] In another embodiment, the current invention provides an apparatus for measuring the depth of a gingival pocket. The apparatus comprises a probe comprising at least one transducer having a pulsed transmitter for transmitting an ultra-sonic signal. The at least one transducer is mounted in the tip of a control arm. The apparatus further comprises at least one gated or un-gated receiver for receiving at least one reflected ultra-sonic signal. The apparatus also has a data processing unit for converting the at least one reflected ultra-sonic signal from a raw waveform to a processed waveform. According to a preferred embodiment, a registration guide sized and configured to fit over the gums of an individual is provided. The registration guide has a plurality of channels therein, the channels being spaced apart to correspond to the locations of gingival pockets in the gums of an individual. Each of the channels is sized and configured to receive the tip of the control arm.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 Illustrates a registration guide according to the invention for the upper gums of an individual.
[0015] FIG. 2 Illustrates a registration guide according to the current invention installed over the upper gums of an individual
[0016] FIG. 3 Illustrates an ultra-sonic probe according to the current invention being used in conjunction with a registration guide in the method according to the current invention.
[0017] FIG. 4 Illustrates an alternate view of an ultra-sonic probe according to the current invention being used in conjunction with a registration guide in the method according to the current invention
DETAILED DESCRIPTION OF THE INVENTION
[0018] In its broadest sense the current method comprises transmitting an ultra-sonic signal through the gum tissue of an individual (transgingivally), as opposed to intra-sulcularly, using an ultra-sonic probe and receiving signals reflected from the gum tissue and underlying structures, wherein the time of flight of the reflected signals and their relative amplitude can be used to determine the topography of the underlying dental structures.
[0019] According to another embodiment of the invention an apparatus for executing the method is provided. In its broadest sense the apparatus comprises an ultra-sonic probe comprising a transducer for emitting an ultra-sonic signal and acquiring a reflected signal. The apparatus further comprises a pulsed transmitter for generating ultra-sonic signals, at least one gated or un-gated receiver for receiving reflected signals in raw waveform, and a processor for processing the raw waveform to a processed waveform which can be used to determine the topography of the underlying dental structures.
[0020] In general, the use of ultra-sound signals to elucidate the internal structures of human and other live subjects takes advantage of the fact that the degree to which a sound wave is absorbed, propagated or reflected by any structure is a function of the density of that structure. For instance, the soft tissue of a human or other live subject has a greater tendency to absorb, rather than propagate or reflect a sound wave, as opposed to a hard bony or tooth structure. Similarly, on the same scale, soft tissue will provide at least some degree of propagation or reflectance, whereas an empty space, such as a gingival pocket will provide a negligible or no reflected or propagated wave. Reflected waves can also be generated by a transition in the density of a structure, such as the boundary between soft gum tissue and hard tooth or bone. Also important to the use of ultra-sonic signals is the fact that as a signal encounters either soft or hard tissue, it is attenuated by absorption of some of the energy of the signal.
[0021] The application of such ultra-sound techniques to the determination of dental structures has been disclosed by previous authors. For example, U.S. Pat. Ser. No. 5,755,571 to Companion discloses a probe, which uses ultra-sound waves projected into the crevice between the tooth and gum tissue (the sulcus) along the surface of the tooth for determining periodontal pocket depth. The method of Companion injects a stream of water into the pocket to act as a transmission medium for ultra-sound waves. In Companion, an ultra-sonic wave projected along the surface of a tooth is reflected by the hard structure of the joining of the gum to the tooth. A draw back of this method is that a reference point needs to be established where the pocket depth is measured to gauge the change in depth of the pocket at a location over time.
[0022] The advantage of the current invention over previously disclosed methods is that it is a transgingival technique, which transmits energy across the gum tissue rather than behind it. This approach is virtually non-invasive to the patient and can be much more comfortable and less likely to transfer the bacteria of the pocket. The inventor has discovered that the topography of dental structures can be efficiently determined by projecting an ultra-sonic wave through the gum tissue of an individual rather than along the surface of the tooth. The current method eliminates the need to inject water into the gingival pocket to act as a transmission medium. Further, the method according to the current invention eliminates the need to establish a reference point for measurement by manual probing as the reference point is part of the transgingival signal. For example, the cemento-enamel junction can be detected based on the variation in the reflected ultra-sonic signal that occurs at the transition from the enamel of the tooth crown to the cementum of the tooth root. The current method still allows data to be compared to data of known periodontal pathological situations thereby learning more about the condition of the pocket.
[0023] The invention will now be described more fully with reference to exemplary drawings. According to the method of the current invention, an ultra-sonic signal is transmitted transgingivally. The ultra-sonic signal is transmitted using an ultra-sonic probe having a transducer which can function to acquire reflected ultra-sonic waves, as well as emit the transmitted signals. In a preferred embodiment the probe has two transducers; one to emit an ultra-sonic signal and the other to acquire reflected signals. Once transmitted from the probe, the ultra-sonic signal will be reflected and further propagated to varying degrees. A portion of the signal will be reflected from the gum surface and be acquired by the probe as a reflected ultra-sonic signal. Another portion of the signal will be further propagated through the gum tissue. In the case that a void, comprising the gingival pocket is located adjacent to the opposite side of the gum tissue into which the ultra-sonic signal is transmitted, no further reflected signal will be acquired past the boundary as the void space will not further propagate the ultra-sonic signal. However, in the event that the ultra-sonic signal propagated through the gum tissue encounters a transition to a structure of a greater density, a further reflected signal will be generated and therefore acquired by the probe. The intensity of the reflected signal acquired from the internal gum boundary will depend on whether the boundary layer is with the empty space of the gingival pocket or with the connection point of the gum to the tooth. According to the preferred embodiment of the current invention, the portion of the ultra-sonic signal propagated through the gum tissue encounters the attachment point of the root of a tooth to the soft tissue of the gum, which represents the bottom of a gingival pocket, and thereby generates a reflected signal. In terms of the visualization of the data acquired according to the method, the areas comprising the gingival pocket will appear as “dark” whereas the location of the tooth attachment, and hence the bottom of the pocket, will appear as relative “bright” spots.
[0024] According to the current invention, by probing the gum surface at varying depths from the gingival margin, the attachment point of a given tooth, and therefore the depth of the gingival pocket at that tooth, can be determined. Further, it is possible to determine further dimensions and topography of the pocket, for example whether the pocket is narrow or broad, or the degree to which the increased depth of a pocket has spread around the circumference of a tooth.
[0025] According to a preferred embodiment of the method, a registration guide is used to aid in precisely locating the areas to be probed. Referring to FIGS. 1 and 2 , a registration guide 102 is shown, which is sized and configured to fit over the gums of an individual 100 . The exterior surface of the registration guide, which comprises the areas in front of, as well as in back of the teeth. The front of the registration guide has a plurality of guide channels 104 A therein, and the back has a second plurality of guide channels 104 B. Individual registration guides can be prepared to fit the upper and lower arch of an individual, and can also be sized to small, medium or large individuals. In a preferred embodiment of the current invention, the registration guide is a disposable one-use component.
[0026] Referring to FIG. 3 , a registration guide 302 is shown inserted over the gums of the upper jaw 300 of an individual. The guide channels 304 are sized and configured to receive the tip 306 of the ultra-sonic probe 308 . The guide channels 304 ensure that the proper angle of incidence of the ultra-sonic signals is achieved, as well as ensuring precise and repeatable measurement of each gingival pocket. In a preferred embodiment, the ultra-sonic probe 306 has a guide arm 310 , which further helps to ensure that the proper angle of incidence of the ultra-sonic signals is achieved, as well as ensuring precise and repeatable measurement of each gingival pocket.
[0027] Referring to FIG. 4 , an alternate view of a registration guide 400 being used in conjunction with an ultra-sonic probe 402 according to the current invention is shown. The tip 404 of the ultra-sonic probe and the guide arm 406 fit into the guide channel 410 to ensure the proper location and orientation of the transducer. The probe tip 404 can be moved within the guide channel 410 as illustrated in FIG. 4 to permit probing at various depths along the gum line, thereby visualizing the underlying dental structures at various depths and identifying the CEJ reference point, which can be placed in a look-up file. If the CEJ has been obliterated by a restoration, that material will have a look-up reference as well. Still referring to FIG. 4 , the space between the inner surface of the registration guide and the gums and teeth is filled with a soft media 408 that will conform to the shape of the gums and teeth, and be a good transmission medium for ultra-sonic signals. The media is preferably a gel or colloidal material.
[0028] The ultra-sonic probe itself comprises a transducer mounted in the tip of a control arm for ease of handling. Preferably, the control arm is flexible to permit easy adjustment of the angle of incidence of the ultra-sonic signal. A pulsed transmitter in electrical connection to the transducer generates an electrical signal, which is converted to an ultra-sonic signal by the transducer. Preferably, the probe operates in the range of 10 to 25 MHz. The transducer also acquires ultra-sonic signals that are reflected by underlying dental structures. One or more receivers, also in electrical connection with the transducer receive the reflected signals acquired by the transducer in raw waveform. The one or more receivers may be gated or un-gated. Preferably, the receivers are gated, which permits the scanning of discrete time intervals, which are established based on the expected time of flight of a signal between when it is generated and a reflected signal is received. For example, based on the estimated thickness of the gum tissue of an individual, which is relatively uniform throughout the population, an estimated time of flight for an ultra-sonic signal reflected from an underlying dental structure can be estimated. Using this estimated time of flight, a gated receiver can be programmed to receive data at only fixed intervals corresponding to the estimated time of flight. In this way a substantial amount of noise can be eliminated when scanning dental structures.
[0029] In a preferred embodiment, the probe has at least two transducers located in the tip of the control arm. A first transducer is in electrical connection to a pulsed transmitter for emitting an ultra-sonic signal. A second transducer is in electrical connection to a gated or ungated receiver for receiving a reflected ultra-sonic signal in raw waveform.
[0030] A processor then processes the raw waveform to produce a processed waveform that can be used to visualize underlying dental structures as well as evidence of pathology such as bleeding, inflammation, or exudate. The processor can be any computer processor capable of performing data transformation. Those skilled in the art will be familiar with methods for transforming raw ultra-sonic signals to a processed waveform. The particular transform method used is not critical to the invention, and therefore all methods are considered within the scope of the invention. The transformed data is then stored in a database for comparison to other measurements taken over time.
[0031] Preferably the ultra-sound technique used by the probe is A-Scan ultra-sound, which is a simple 1-axis technique. Other ultra-sound techniques, such as B-Scan and A/B-Scan are also considered within the scope of the invention.
[0032] It is contemplated that the method and apparatus of the current invention will have multiple applications in the area of dentistry beyond the determination of the depth of a gingival pocket. For example, it is contemplated that the method and apparatus of the current invention could be used to map the dental structures of an individual, such as the location of teeth, restorations, and other landmarks. The initial mapping could then be used as an impression on an ongoing basis to determine the progression of cracks, fractures, cavities and other conditions of both hard and soft tissue, and relate to the articulation of the upper and lower dental arches. This mapping could assist in fabrication of dental restorations. It is also contemplated that the signal data can be used for comparisons to know pathological pocket conditions such as inflammation or infection, thereby portraying not only the depth of the pocket, but the physiologic condition of the pocket as well. Thus, the invention in not limited to the specific embodiments presented here.
[0033] The invention has thus been described in detail with reference to exemplary drawings. Those skilled in the art will recognize that the invention is not limited to those examples provided herein. The full scope of the invention will be clear from the claims appended hereto. | A method and apparatus are provided for determining the depth of a gingival pocket using ultra-sound signals transmitted transgingivally. Transgingival (through the gum) transmission of the ultra-sonic signal permits a completely non-invasion determination of the dental health of an individual. In addition to determining the depth of a gingival pocket the health or disease of the pocket could be determined. The current invention allows for mapping of the underlying dental features of an individual for later comparison to future ultra-sound scans and to assist in fabrication of dental restorations. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of co-pending U.S. Provisional Patent Application Ser. No. 61/534,486, entitled “Method and Apparatus for Treating Pests,” filed Sep. 14, 2011, the technical disclosure of which is hereby incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The present invention relates to a method and apparatus for controlling water pests.
[0004] 2. Description of Related Art
[0005] Mussels and other such water pests infest waterways and clog intake pipes. One such example is the Zebra mussel, Dreissena polymorpha . These mussels attach and cluster atop virtually any solid surface. This is problematic when the surface is a water intake pipe as the mussels restrict flow through the pipe. Further mussels undesirably attach to ships' ballasts. Finally, these and other pests often carry dangerous and undesirable diseases, including water borne diseases, which are harmful to humans or other wildlife. Consequently, there is a need to be able to kill or remove the mussels and other such pests.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will be best understood by reference to the following detailed description of illustrative embodiments when read in conjunction with the accompanying drawings, wherein:
[0007] FIG. 1 is a perspective view of one embodiment of an endod device in a disk shape.
[0008] FIG. 2 is a perspective view of an endod device in one embodiment.
[0009] FIG. 3 is a perspective view of an endod tablet in one embodiment.
DETAILED DESCRIPTION
[0010] Several embodiments of Applicants' invention will now be described with reference to the drawings. Unless otherwise noted, like elements will be identified by identical numbers throughout all figures. The invention illustratively disclosed herein suitably may be practiced in the absence of any element which is not specifically disclosed herein.
[0011] It has been discovered that Phytolacca dodecandra , generally known as Endod or African Soapberry, is useful in the killing of mussels and other such water pests. One example of such pests is the Zebra mussel. Pests include mussels, snails, mollusks, and other such life forms which are to be controlled. These pests often carry many diseases which can be spread to humans and domesticated animals. For example schistosomiasis is spread via snails. This is very common in rice paddies throughout Asia. Consequently, by controlling snails, for example, the spread of schistosomiasis can be decreased.
[0012] Endod is degradable which makes it suitable for use in waterways. It is believed that the effective ingredient in endod is saponin. Endod has been found safe for humans and domesticated animals. Thus, endod can be applied in common waterways with minimal, if any, unintended environmental impact.
[0013] Successful application of endod results in either killing the pest or rendering them incapable of latching onto surfaces. An application of endod which results in either the killing of pests, or rendering them incapable of latching onto surfaces is referred to as an effective application. The concentration of endod as well as the length of application can be adjusted during the application to reach an effective application. It can be appreciated that in some embodiments an effective application can comprise a lower concentration (ppm) along with a longer application (hours).
[0014] Endod can be applied in a variety of different ways. In one embodiment the endod berries are ground to form a powder. The powder can then be suspended in a liquid medium, such as water. The amount of endod in the solution can be adjusted, but it has been found that an effective concentration of between 5 ppm and about 20 ppm has been sufficient to either kill pests or render them incapable of latching onto surfaces.
[0015] FIG. 1 is a perspective view of one embodiment of an endod device in a disk shape. FIG. 1 shows a pipe 100 . The pipe 100 can be an intake pipe, an outlet pipe, virtually any pipe through which water flows. As illustrated the pipe 100 has an outer diameter 101 , and an inner diameter 102 .
[0016] FIG. 1 also shows an endod device 103 . An endod device 103 is a device which comprises endod. The endod can be contained within the device 103 or the endod can be applied to the surface of the endod device 103 . In one embodiment, the endod is applied to the device 103 via a binder. A binder is any substance which holds endod within and/or onto the device 103 . The endod can be dissolved in the binder, or the endod can be applied to the surface of the binder. As will be described below, in one embodiment the binder is water soluble.
[0017] As depicted the endod device 103 comprises a disk, although the device 103 can comprise a variety of shapes. In one embodiment the device 103 has an outer diameter which is slightly less than the inner diameter 102 of the pipe 100 . Slightly less refers to a first value which is between about 80% and about 100% of a second value. In one embodiment the device 103 has an outer diameter which is between about 90% and about 100% of the inner diameter 102 of the pipe 100 .
[0018] As depicted the device 103 is a disk which has a central opening. In other embodiments the disk comprises two or more openings. In still other embodiments the device 103 does not comprise a central opening but instead is water permeable. In such an embodiment water flows through the device 103 . In one embodiment the shape of the device 103 is substantially similar to the cross-section of the pipe 100 . In other embodiments the device 103 comprises the shape of a cube, ball, or other solid surface. The device 103 can comprise virtually any shape.
[0019] As noted, in one embodiment the device 103 comprises endod. In one embodiment the endod device 103 comprises a slow release endod device. As used herein, a slow release endod device is a device which is still releasing endod after 2 hours. In one embodiment the slow release endod is still releasing endod after 8 hours. The time release properties of the endod on the device 103 can be adjusted for a variety of factors including the size of the pipe, the flow rate through the pipe, the length of the pipe, etc. It can be appreciated that if all of the endod was simply released at a single point, the endod would disperse through and with the flowing fluid. As such, the residence time of the endod within the pipe and around the pests would be minimal. However, a slow release allows some endod to be released over time which increases the time in which the pests are exposed to endod, referred to herein as the exposure time.
[0020] It has been discovered that some mussels and other such pests can sense chlorine and other chemicals in the water. When this happens, the pests do not circulate or otherwise take-in air and/or water for a period of between 1 and 8 hours. Accordingly, in one embodiment the duration of the application of the endod is greater than 8 hours. This ensures the exposure time will be greater than the time that the pests do not circulate air/water. Consequently, the pest will be exposed to endod. As such, in one embodiment the slow release properties of the disk allow the endod to be released for a period greater than 8 hours.
[0021] The time release properties of the endod and the device 103 can be achieved in a variety of ways. In one embodiment the endod is encapsulated in the device 103 via a binder. As noted, in one embodiment the binder comprises a water soluble substance. Thus, as the water soluble substance dissolves over time, the endod which was encapsulated or otherwise sealed by the water soluble substance is released. The water soluble substance can comprise any substance which slowly dissolves in water and which is non-reactive to the endod. Examples of such a water soluble substance includes but is not limited to some salts and sugars.
[0022] In one embodiment the device 103 is a permanent feature secured temporarily to a location upstream of the pests which are to be removed. For example, the device 103 can be located near the intake of the pipe 100 . FIG. 2 illustrates a perspective view of an endod device in one embodiment. The device 103 can be secured via any device known in the art including welding, screwing, bolting, etc. Thus, water flows around and/or through the device 103 and distributes the endod to the pests 104 .
[0023] Referring back to FIG. 1 it can be seen that the device 103 comprises a disk shape. As noted, in one embodiment the outer diameter of the device 103 is slightly less than the inner diameter of the pipe 100 . In one embodiment the device 103 operates as previously described by releasing endod over time. Thus, the pests 104 of this embodiment are removed via a chemical means. However, in one embodiment the device 103 further provides a mechanical force to remove the pests. As seen in FIG. 1 , water applies a force against the device 103 in an attempt to push the device 103 downstream. As the device 103 is forced downstream it slowly releases endod. Simultaneously, while advancing downstream the device 103 brushes against the inner diameter 102 of the pipe 100 . While advancing downstream, however, the device 103 is stopped by the presence of mussels 104 which have yet to release. Put differently, the device 103 cannot advance downstream because pests 104 block the device's 103 further movement. As such, the force of the water pressed against the downstream end of the device 103 which applies a force against the pests 104 . The obstructing pests 104 become weak due in part to the presence of the endod as well as the pressure of the device 103 . Thus, the obstructing pests 104 eventually lose their grip and fall. The device 103 is then advanced further downstream where it may or may not abut against additional obstructing pests 104 .
[0024] As noted, in one embodiment the endod device 103 maintains its shape as it advances through the pipe 100 . As such, in one embodiment the endod device 103 comprises sufficient rigidity to retain its shape. In such embodiments, this rigidity prevents the endod device 103 from contorting. Accordingly, the endod device 103 maintains its shape and thus advances along the inside diameter of the pipe 100 . Without sufficient rigidity, the endod device 103 could bend and flow through the pipe 100 without encountering any obstructing pests 104 .
[0025] As described there are several methods of treating pests utilizing an endod device. In one embodiment an endod device is first obtained. Thereafter, the endod device is placed in a pipe. In one embodiment the device is secured within the pipe. In other embodiments the endod device is advanced downstream through the pipe.
[0026] This method offers several unexpected benefits. First, this method allows the combination of mechanical and chemical means to remove the pests. Further, in one embodiment because the released endod is in close proximity with the obstructing mussel, the obstructing mussel receives a high concentration blast of endod. This is because the endod has not yet had an opportunity to diffuse within the flowing water. Thus, the obstructing pests receive a concentrated blast of endod as well as an applied force of the device 103 . The combined forces ensure the pests release their grip.
[0027] Another benefit is that, in some embodiments, when the device 103 reaches any downstream location, the operator is ensured that the pipe surfaces upstream of the device 103 have been successfully cleaned. As an example, in FIG. 1 the pipe comprises a removable filter 105 . A filter prevents larger items from passing downstream of the filter. For example, if FIG. 1 shows the intake to a pump it may be desirable to minimize the passage of any large items to the pump. A removable filter 105 helps trap items of a specified size from flowing downstream of the filter. Any filter 105 known in the art can be used. As noted above, if the device 103 is stopped at the filter 105 , then the operator knows that the pipe 100 upstream of the filter 105 has been successfully cleaned. The filter 105 can also act to capture released pests. It should be noted that in some embodiments the entire endod device 103 is water soluble.
[0028] FIG. 3 is a perspective of an endod tablet in one embodiment. In this embodiment the tablet 308 comprises endod 306 as well as a water soluble binder 307 . In operation the tablet 308 is dropped into a body of water comprising pests. In one embodiment the tablet 308 is a time release tablet which releases endod over time. In one embodiment the tablet 308 is still releasing endod after 8 hours. The water soluble substance 307 can comprise any water soluble substance previously described. The amount of endod 306 per tablet can be adjusted for a variety of factors.
[0029] In operation at least one tablet 308 is inserted within a body of water comprising pests. The tablet 308 releases the endod 306 which subsequently kills the pests or renders them incapable of latching onto solid surfaces. In one embodiment the first step is determining the amount of endod required for an effective application. In one embodiment the first step comprises determining the approximate volume of water to be treated. Thereafter, the proper amount of tablets 308 is inserted into the water.
[0030] As noted, there are several unexpected results. First, removing undesirable pests from solid surfaces resulted in increased flow though pipes, better functioning ballasts, and cleaner solid surfaces. Additionally, killing disease carrying pests prevents the spreading of many diseases. Finally, because endod is safe for the environment and humans, any unintended environmental concerns are minimized.
[0031] In still another embodiment pipes and other items, such as a ship's ballast, are pre-treated with endod. For example, a pipe can be coated with a slow release coating which comprises endod. In one embodiment the slow release coating slowly releases endod for a period of many months. In such embodiments the pre-coated pipes would prevent the accumulation of pests. This method can be supplemented with the other methods and devices discussed herein.
[0032] While the invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.
ADDITIONAL DESCRIPTION
[0033] The following clauses are offered as further description of the disclosed invention.
[0000] 1. A method of treating pests, said method comprising the steps of:
[0034] a. obtaining an endod device, wherein said endod device comprises endod;
[0035] b. placing said endod device in a pipe.
[0000] 2. The method according to any preceding clause wherein said endod device further comprises a binder.
3. The method according to clause 2 wherein said binder is water soluble.
4. The method according to any preceding clause wherein said endod device comprises a disk.
5. The method according to clause 4 wherein said disk comprises an outer diameter, and wherein said water pipe comprises an inner diameter, wherein said outer diameter of said disk is slightly less than the inner diameter of said pipe.
6. The method according to any preceding clause wherein said pipe comprises a population of pests.
7. The method according to any preceding clause further comprising:
[0036] c. advancing said endod device downstream through said water pipe.
[0000] 8. The method according to any preceding clause wherein said placing of step b) comprises securing said endod device within said pipe.
9. The method according to any preceding clause wherein said endod device is a slow release endod device.
10. The method according to any preceding clause wherein said placing comprises placing an effective application of endod.
11. A method of treating pests in a body of water, said method comprising the steps of:
[0037] a. obtaining an endod tablet, wherein said tablet comprises endod and a binder;
[0038] b. placing said endod tablet into said body of water.
[0000] 12. The method according to clause 11 further comprising the step of calculating an effective amount of endod, wherein said calculating step occurs prior to said placing of step b).
13. A device for treating pests, said device comprising:
[0039] endod; and
[0040] a binder.
[0000] 14. The device according to clause 13 wherein said device is a tablet.
15. The device according to clauses 13-14 wherein said device is a disk.
16. The device according to clauses 13-15 wherein said binder is water soluble.
17. The device according to clauses 13-16 wherein said device is a slow release endod device. | A device for treating pests and method for using the same. The device comprises an effective amount of endod. The device can be placed in a body of water wherein the endod treats the pests. Additionally the device can be placed in a pipe whereby a combination of the endod and the mechanical force of the water removes the pests in the pipe. | 1 |
TECHNICAL FIELD
[0001] The present invention relates to laundry detergent compositions containing a combination of anionic and specified nonionic surfactants giving improved oily soil detergency, especially under hard water conditions.
BACKGROUND
[0002] Heavy duty laundry detergent compositions have for many years contained anionic sulphonate or sulphate surfactant, for example, linear alkylbenzene sulphonate (LAS), together with ethoxylated nonionic surfactants. Examples abound in the published literature.
[0003] The preferred ethoxylated alcohol nonionic surfactants giving an optimum balance of properties have generally been those having an alkyl chain length of C 12 -C 15 and an average degree of ethoxylation of 1 to 10, preferably 3 to 7, more preferably about 5.
[0004] Longer-chain alcohols having a higher degree of ethoxylation, for example, tallow alcohol (C 18 ) 11EO, have also been used.
[0005] These relatively hydrophobic materials of low HLB value are generally liquids at ambient temperature and exhibit excellent oily soil removal.
[0006] Longer-chain alcohols having higher degrees of ethoxylation, for example, tallow (C 18 ) alcohol 25EO and 50EO, are solids at ambient temperature and are used as slowly dissolving coating materials, for example, for enzyme or antifoam granules.
[0007] It has now surprisingly been found that ethoxylated alcohols combining a shorter alkyl chain length and a higher degree of ethoxylation, when used in minor amounts together with an anionic sulphonate or sulphate surfactant, can give enhanced oily soil removal. The benefit is especially great under hard water conditions.
PRIOR ART
[0008] WO 94 16052A (Unilever) discloses high bulk density laundry powders based on LAS and conventional nonionic surfactants, and containing small amounts of very highly ethoxylated alcohols, eg tallow alcohol 80EO, as a dissolution aid.
[0009] EP 293 139A (Procter & Gamble) discloses twin-compartment sachets containing detergent powders. Some powders contain very small amounts of tallow alcohol 25EO.
[0010] WO 93 02176A (Henkel) discloses the use of highly ethoxylated aliphatic alcohols as “structure breakers” in high bulk density powders containing conventional nonionic surfactants.
[0011] U.S. Pat. No. 4,294,711 (Procter & Gamble) discloses a textile softening heavy duty detergent composition containing 1 wt % of tallow alcohol 80EO.
[0012] WO 92 18594A (Procter & Gamble) discloses builder granules of layered silicate coated with tallow alcohol 50EO.
[0013] EP 142 910A and EP 495 345A (Procter & Gamble) disclose antifoam granules containing highly ethoxylated alcohols.
[0014] WO 93 19148A (Procter & Gamble) discloses liquid hard surface cleaning compositions containing highly ethoxylated nonionic surfactants optionally plus anionic surfactant.
[0015] GB 2 279 660A (Procter & Gamble) discloses a liquid laundry detergent composition containing a solid water-insoluble organic peroxyacid bleach and a C 8 -C 20 2-2EO ethoxylated alcohol nonionic surfactant, but only lower ethoxylates (9EO and below) are specifically disclosed.
[0016] WO 98 18892A (Du Pont) discloses a carpet cleaning formulation containing a C 10 -C 16 ethoxylated alcohol of HLB value 10.5-15.
DEFINITION OF THE INVENTION
[0017] The present invention provides a built laundry detergent composition comprising
[0018] (i) from 5 to 40 wt %, preferably from 7 to 30 wt %, of surfactant consisting essentially of:
[0019] (i)(a) from 60 to 99 wt %, preferably from 80 to 95 wt %, based on the surfactant (i), of anionic sulphonate or sulphate surfactant,
[0020] (i)(b) from 1 to 40 wt %, preferably from 5 to 20 wt %, based on the surfactant (i), of an ethoxylated alcohol nonionic surfactant of the formula
R—(—O—CH 2 —CH 2 ) n —OH
[0021] wherein R is a hydrocarbyl chain having from 8 to 16 carbon atoms, and the average degree of ethoxylation n is from 20 to 50,
[0022] (ii) from 10 to 80 wt % of detergency builder,
[0023] (iii) optionally other detergent ingredients to 100 wt %.
[0024] The invention also provides a process for laundering textile fabrics by machine or hand, which includes the step of immersing the fabrics in a wash liquor comprising water in which a laundry detergent composition as defined in the previous paragraph is dissolved or dispersed, wherein the water has a hardness of at least 20 degrees (French).
[0025] The invention further provides the use of a surfactant (i) consisting essentially of
[0026] (i)(a) from 60 to 99 wt %, preferably from 80 to 95 wt %, based on the surfactant (i), of anionic sulphonate or sulphate surfactant,
[0027] (i)(b) from 1 to 40 wt %, preferably from 5 to 20 wt %, based on the surfactant (i), of an ethoxylated alcohol nonionic surfactant of the formula
R—(—O—CH 2 —CH 2 ) n —OH
[0028] wherein R is a hydrocarbyl chain having from 8 to 16 carbon atoms, and the average degree of ethoxylation n is from 20 to 50,
[0029] in a laundry detergent composition in an amount of from 5 to 40 wt %, to improve the oily soil detergency of the composition especially in water having a hardness of at least 20 degrees (French).
DETAILED DESCRIPTION OF THE INVENTION
[0030] Detergent compositions of the invention provide increased detergency on oily soils, especially under hard water conditions, for example, using water of a hardness of at least 20 degrees (French). The benefit is especially apparent at very high water hardnesses, for example, more than 30 degrees (French).
[0031] The Surfactant Combination (i)
[0032] The detergent compositions of the invention contain a combination of an anionic sulphonate or sulphate surfactant, and a defined nonionic surfactant. The total amount of the two surfactants is from 5 to 40 wt %, preferably from 7 to 30 wt %.
[0033] The surfactant combination consists essentially of from 60 to 99 wt %, preferably from 80 to 95 wt % and more preferably from 85 to 95 wt %, of anionic sulphonate or sulphate detergent, and from 1 to 40 wt %, preferably from 5 to 20 wt % and more preferably from 5 to 15 wt %, of the defined nonionic surfactant.
[0034] In the compositions of the invention, the weight ratio of anionic surfactant (i)(a) to nonionic surfactant (i)(b) is from 2:1 to 25:1, preferably from 3:1 to 20:1. Especially good results are obtained when the ratio is from 5:1 to 10:1.
[0035] The whole product (composition) preferably contains:
[0036] (i)(a) from 3 to 30 wt %, preferably from 5 to 25 wt %, of the anionic sulphonate or sulphate surfactant, and
[0037] (i)(b) from 0.5 to 10 wt %, preferably from 1 to 5 wt %, of the nonionic surfactant (i)(b).
[0038] Optionally minor, non-interfering amounts of other surfactants may also be present. Preferably, however, the composition is free from nonionic surfactants other than the defined nonionic surfactant (i)(b).
[0039] More preferably the composition is substantially free of other non-soap surfactants.
[0040] Optionally soap may also be present, for example, in an amount of from 1 to 5 wt %.
[0041] The Anionic Surfactant (i)(a)
[0042] The anionic surfactant is a sulphonate or sulphate anionic surfactant.
[0043] Anionic surfactants are well-known to those skilled in the art. Many suitable detergent-active compounds are available and are fully described in the literature, for example, in “Surface-Active Agents and Detergents”, Volumes I and II, by Schwartz, Perry and Berch.
[0044] Examples include alkylbenzene sulphonates, primary and secondary alkylsulphates, particularly C 8 -C 15 primary alkyl sulphates; alkyl ether sulphates; olefin sulphonates; alkyl xylene sulphonates; dialkyl sulphosuccinates; and fatty acid ester sulphonates. Sodium salts are generally preferred.
[0045] Preferably the anionic surfactant is linear alkylbenzene sulphonate or primary alcohol sulphate. More preferably the anionic surfactant is linear alkylbenzene sulphonate.
[0046] The Ethoxylated Nonionic Surfactant (i)(b)
[0047] The nonionic surfactant is an ethoxylated aliphatic alcohol of the formula
R—(—O—CH 2 —CH 2 ) n —OH
[0048] wherein R is a hydrocarbyl chain having from 8 to 16 carbon atoms, and the average degree of ethoxylation n is from 20 to 50.
[0049] The hydrocarbyl chain, which is preferably saturated, preferably contains from 10 to 16 carbon atoms, more preferably from 12 to 15 carbon atoms. In commercial materials containing a spread of chain lengths, these figures represent an average.
[0050] The alcohol may be derived from natural or synthetic feedstock. Preferred alcohol feedstocks are coconut, predominantly C 12 -C 14 , and oxo C 12 -C 15 alcohols. Longer chain materials such as tallow or hardened tallow (C 18 ) are not preferred.
[0051] The average degree of ethoxylation ranges from 20 to 50, preferably from 25 to 40.
[0052] Preferred materials have an average alkyl chain length of C 12 -C 16 and an average degree of ethoxylation of 25 to 40.
[0053] An example of a suitable commercially available material is Lutensol (Trade Mark) A030, ex BASF, which is a C 13 -C 15 alcohol having an average degree of ethoxylation of 30.
[0054] Detergency Builder (ii)
[0055] The compositions may suitably contain from 10 to 80%, preferably from 15 to 70% by weight, of detergency builder. Preferably, the quantity of builder is in the range of from 15 to 50% by weight.
[0056] Preferably the builder is selected from sodium tripolyphosphate, zeolite, sodium carbonate, sodium citrate, layered silicate, and combinations of these.
[0057] The zeolite used as a builder may be the commercially available zeolite A (zeolite 4A) now widely used in laundry detergent powders. Alternatively, the zeolite may be maximum aluminium zeolite P (zeolite MAP) as described and claimed in EP 384 070B (Unilever), and commercially available as Doucil (Trade Mark) A24 from Ineos Silicas Ltd, UK. Zeolite MAP is defined as an alkali metal aluminosilicate of zeolite P type having a silicon to aluminium ratio not exceeding 1.33, preferably within the range of from 0.90 to 1.33, preferably within the range of from 0.90 to 1.20. Especially preferred is zeolite MAP having a silicon to aluminium ratio not exceeding 1.07, more preferably about 1.00. The particle size of the zeolite is not critical. Zeolite A or zeolite MAP of any suitable particle size may be used.
[0058] Also preferred according to the present invention are phosphate builders, especially sodium tripolyphosphate. This may be used in combination with sodium orthophosphate, and/or sodium pyrophosphate.
[0059] Other inorganic builders that may be present additionally or alternatively include sodium carbonate, layered silicate, amorphous aluminosilicates.
[0060] Organic builders that may be present include polycarboxylate polymers such as polyacrylates and acrylic/maleic copolymers; polyaspartates; monomeric polycarboxylates such as citrates, gluconates, oxydisuccinates, glycerol mono-di- and trisuccinates, carboxymethyloxysuccinates, carboxy-methyloxymalonates, dipicolinates, hydroxyethyliminodiacetates, alkyl- and alkenylmalonates and succinates; and sulphonated fatty acid salts.
[0061] Organic builders may be used in minor amounts as supplements to inorganic builders such as phosphates and zeolites. Especially preferred supplementary organic builders are citrates, suitably used in amounts of from 5 to 30 wt %, preferably from 10 to 25 wt %; and acrylic polymers, more especially acrylic/maleic copolymers, suitably used in amounts of from 0.5 to 15 wt %, preferably from 1 to 10 wt %.
[0062] Builders, both inorganic and organic, are preferably present in alkali metal salt, especially sodium salt, form.
[0063] Other Detergent Ingredients
[0064] As well as the surfactants and builders discussed above, the compositions may optionally contain bleaching components and other active ingredients to enhance performance and properties.
[0065] These optional ingredients may include, but are not limited to, any one or more of the following: soap, peroxyacid and persalt bleaches, bleach activators, sequestrants, cellulose ethers and esters, other antiredeposition agents, sodium sulphate, sodium silicate, sodium chloride, calcium chloride, sodium bicarbonate, other inorganic salts, fluorescers, photobleaches, polyvinyl pyrrolidone, other dye transfer inhibiting polymers, foam controllers, foam boosters, acrylic and acrylic/maleic polymers, proteases, lipases, cellulases, amylases, other detergent enzymes, citric acid, soil release polymers, fabric conditioning compounds, coloured speckles, and perfume.
[0066] Detergent compositions according to the invention may suitably contain a bleach system. The bleach system is preferably based on peroxy bleach compounds, for example, inorganic persalts or organic peroxyacids, capable of yielding hydrogen peroxide in aqueous solution. Suitable peroxy bleach compounds include organic peroxides such as urea peroxide, and inorganic persalts such as the alkali metal perborates, percarbonates, perphosphates, persilicates and persulphates. Preferred inorganic persalts are sodium perborate monohydrate and tetrahydrate, and sodium percarbonate. Especially preferred is sodium percarbonate having a protective coating against destabilisation by moisture. Sodium percarbonate having a protective coating comprising sodium metaborate and sodium silicate is disclosed in GB 2 123 044B (Kao).
[0067] The peroxy bleach compound is suitably present in an amount of from 5 to 35 wt %, preferably from 10 to 25 wt %.
[0068] The peroxy bleach compound may be used in conjunction with a bleach activator (bleach precursor) to improve bleaching action at low wash temperatures. The bleach precursor is suitably present in an amount of from 1 to 8 wt %, preferably from 2 to 5 wt %.
[0069] Preferred bleach precursors are peroxycarboxylic acid precursors, more especially peracetic acid precursors and peroxybenzoic acid precursors; and peroxycarbonic acid precursors. An especially preferred bleach precursor suitable for use in the present invention is N,N,N′,N′-tetracetyl ethylenediamine (TAED). Also of interest are peroxybenzoic acid precursors, in particular, N,N,N-trimethylammonium toluoyloxy benzene sulphonate.
[0070] A bleach stabiliser (heavy metal sequestrant) may also be present. Suitable bleach stabilisers include ethylenediamine tetraacetate (EDTA) and the polyphosphonates such as Dequest (Trade Mark), EDTMP.
[0071] The detergent compositions may also contain one or more enzymes. Suitable enzymes include the proteases, amylases, cellulases, oxidases, peroxidases and lipases usable for incorporation in detergent compositions.
[0072] In particulate detergent compositions, detergency enzymes are commonly employed in granular form in amounts of from about 0.1 to about 3.0 wt %. However, any suitable physical form cf enzyme may be used in any effective amount.
[0073] Antiredeposition agents, for example cellulose esters and ethers, for example sodium carboxymethyl cellulose, may also be present.
[0074] The compositions may also contain soil release polymers, for example sulphonated and unsulphonated PET/POET polymers, both end-capped and non-end-capped, and polyethylene glycol/polyvinyl alcohol graft copolymers such as Sokolan (Trade Mark) HP22. Especially preferred soil release polymers are the sulphonated non-end-capped polyesters described and claimed in WO 95 32997A (Rhodia Chimie).
[0075] Product Form and Preparation
[0076] The compositions of the invention may be of any suitable physical form, for example, particulates (powders, granules, tablets), liquids, pastes, gels or bars.
[0077] According to one especially preferred embodiment of the invention, the detergent composition is in particulate form.
[0078] Powders of low to moderate bulk density may be prepared by spray-drying a slurry, and optionally postdosing (dry-mixing) further ingredients. “Concentrated” or “compact” powders may be prepared by mixing and granulating processes, for example, using a high-speed mixer/granulator, or other non-tower processes.
[0079] Tablets may be prepared by compacting powders, especially “concentrated” powders.
[0080] Also preferred are liquid detergent compositions, which may be prepared by admixing the essential and optional ingredients in any desired order to provide compositions containing the ingredients in the the requisite concentrations.
EXAMPLES
[0081] The invention is illustrated in further detail by the following non-limiting Examples, in which parts and percentages are by weight unless otherwise stated.
Examples 1 to 4, Comparative Example A
Performance Appraisal of Anionic/nonionic Surfactant Mixtures on Kitchen Grease Soil in Hard Water
[0082] Surfactant mixtures were prepared by mixing sodium linear alkylbenzene sulphonate (LAS) and the ethoxylated nonionic surfactant Lutensol AO30 (R=C 12 -C 15 alkyl, n has an average value of 30), in various proportions ranging from 95:5 (19:1) to 80:20 (4:1).
[0083] Medium suds detergent compositions suitable for the machine wash were prepared to the following general formulation:
Total surfactant (LAS plus nonionic) 16.00 Sodium tripolyphosphate 34.00 Sodium carboxymethyl cellulose 0.50 Sodium silicate 7.00 Sodium hydroxide 0.45 Sodium chloride 2.00 Fluorescers 0.15 Silicone fluid antifoam 0.05 Acrylic polymer 1.00 Sodium aluminosilicate 0.50 Sodium carbonate 3.58 Sodium perborate tetrahydrate 7.67 Tetracetyl ethylenediamine 2.21 Enzyme granules 1.64 Soil release polymer 0.35 Citric acid 1.00 Antifoam granules 3.00 Coloured speckles (sodium tripolyphosphate) 1.80 Perfume 0.33 Miscellaneous salts, water etc to 100
[0084] Soil removal performance on knitted polyviscose fabrics was measured in a tergotometer test. The soil used was soya bean oil (chosen as a typical greasy kitchen soil), coloured with a violet dye (0.08 wt %) to act as a visual indicator.
[0085] Test cloths (10 cm×10 cm), each soiled with 0.5 ml of violet-dyed soya bean oil, were washed in tergotometers using the detergent compositions above under the following conditions:
Temperature 25° C. Liquor to cloth ratio 30:1 Product dosage 2.0 g/l Water hardness (° French) 40 Soak time 10 min Wash time (agitation) 15 min
[0086] These conditions corresponded to a pK Ca 2+ of 4.0.
[0087] The reflectance ΔE, indicative of total colour change (of the violet dye) across the whole visible spectrum, of each test cloth was measured before and after the wash. The results expressed as the difference ΔΔE between reflectance values ΔE before and after the wash are shown in the following table. These results are averaged over 2 replicates.
wt % of total surfactant Ratio ΔΔE Nonionic LAS: Mean Example LAS AO30 nonionic Exp 1 Exp 2 ΔΔΔE A 100 0 — 14.9 13.4 — 1 95 5 19:1 17.2 15.7 +2.3 2 90 10 9:1 18.3 17.6 +3.8 3 85 15 5.67:1 19.0 18.1 +4.4 4 80 20 4:1 15.7 16.8 +4.2
Examples 5 and 6: Particulate Detergent Compositions
[0088] Example 5 is a low suds formulation suitable for use in a closed drum washing machine. Example 6 is a high suds formulation suitable for use in a top-loading washing machine or for washing by hand.
5 6 LAS 7.80 20.40 Nonionic (Lutensol AO30) 2.00 3.60 Total surfactant (LAS plus nonionic) 9.80 24.00 Ratio LAS:nonionic (:1) 3.90 5.67 Soap 4.00 — Sodium tripolyphosphate 25.00 14.50 Sodium carboxymethyl cellulose 0.50 0.33 Sodium neutral silicate 8.96 6.98 Sodium sulphate 22.84 17.75 Fluorescers 0.13 0.19 Acrylic/maleic copolymer — 1.50 Sodium carbonate 5.31 15.00 Sodium perborate monohydrate 5.84 8.00 Tetracetyl ethylenediamine 2.10 2.40 Phosphonate sequestrant 0.50 0.40 Enzyme granules 0.97 0.91 Antifoam granules 2.00 — Soil release polymer 0.50 0.80 Perfume 0.36 0.30 Miscellaneous salts, water etc to to 100 100 | A built laundry detergent composition contains anionic surfactant in combination with a minor amount of a highly ethoxylated nonionic surfactant which is a C 8 -C 16 alcohol ethoxylated with an average of from 20 to 50 ethylene oxide groups. The composition exhibits improved oily soil detergency especially under hard water conditions. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a reproducing method and a reproducing apparatus for an optical recording medium having a recording layer of a photochromic material etc. which reacts in a photon mode.
2. Description of the Background Art
In recent years, deep study is made on application of a photochromic material to a reloadable optical recording medium. When such a photochromic material is irradiated with light of a prescribed wavelength, its molecular structure is changed by photochemical reaction. Further, optical characteristics such as absorbance and a refractive index are additionally changed with respect to light of a constant wavelength, while the changed molecular structure can return to the original state when the photochromic material is irradiated with light of another wavelength or heated. Due to such properties, the photochromic material can be applied to an optical recording medium. In such an optical recording medium, it is possible to record information by irradiating the medium with light of a specific wavelength thereby changing its molecular structure, while the recorded information can be reproduced by detecting resulting changes of its optical characteristics, particularly absorbance. In relation to such an optical recording medium of a photon mode, it is well known that its reproducing power is disadvantageously reduced when the recorded information is repeatedly reproduced. Since photochromic molecules react in a photon mode, such reaction of the molecules slightly progresses even if the information is reproduced at a relatively low power level, to reduce the reproducing power following repetitive reproduction. As to a possible solution for such a problem, two methods are now under study.
The first method is adapted to reproduce information by detecting changes of optical characteristics other than absorbance, i.e., optical rotatory power, refractive index, birefringence etc., following photochromic reaction, with light of a wavelength allowing no absorption by the photochromic material. The second method is directed to development of the so-called gate type photochromic material which reacts only when a magnetic field, an electric field, heat or the like is applied thereto in addition to light.
However, it is difficult to apply the first method to multiplex recording which is prevailing means for high densification, for example. As to the second method, on the other hand, no success has yet been attained in synthesis of a gate type photochromic material which is responsive to a magnetic or electric field. Further, a heat gate type photochromic material loses high resolution, which characterizes the photon mode, by thermal diffusion.
SUMMARY OF THE INVENTION
An object of the present invention is to provide absolutely novel reproducing method and apparatus for an optical recording medium, not belonging to the aforementioned two conventional methods, which can remarkably improve the number of reproducible times even if information is reproduced with light in a wavelength band allowing absorption by a photochromic material.
A reproducing method according to a first aspect of the present invention, which is adapted to reproduce information from an optical recording medium provided with a recording layer reacting in a photon mode, comprises a step of irradiating the recording layer with a reproducing beam, and a step of detecting the reproducing beam passing through the recording layer for reproducing recorded and unrecorded states. The feature of this method resides in that the recording layer is irradiated with a reproducing beam whose power is set in proximity to P rep (W) in the following expression: ##EQU3## where SNR represents an S-N power ratio (PP/rms) required for the system, e represents an elementary electric charge of 1.6×10 -19 (C), B represents a bandwidth (Hz) of the system, η represents sensitivity (A/W) of a photodetector to a gain 1, γ represents pickup efficiency, R ave represents an average reflectance of the optical recording medium, and ΔR represents a difference in reflectance between recorded and unrecorded portions of the optical recording medium.
The term "proximity" indicates a one-digit range of 0.5 to 5 times, since the reproducing power level is related to a logarithmic change in the present invention.
A reproducing method according to a second aspect of the present invention, which is adapted to reproduce information from an optical recording medium provided with a recording layer reacting in a photon mode, comprises a step of irradiating the recording layer with a reproducing beam, and a step of detecting the reproducing beam passing through the recording layer for reproducing recorded and unrecorded states. The feature of this method resides in that power of the reproducing beam is set within a range of P rep (W) in the following expression (II): ##EQU4## where SNR represents an S-N power ratio (PP/rms) required for the system, e represents an elementary electric charge of 1.6×10 -19 (C), B represents a bandwidth (Hz) of the system, η represents sensitivity (A/W) of a photodetector to a gain 1, γ represents pickup efficiency (efficiency of reflected light from the medium for reaching the photodetector), R ave represents an average reflectance of the optical recording medium, ΔR represents a difference in reflectance between recorded and unrecorded portions of the optical recording medium, k represents the Boltzman constant of 1.38×10 -23 (J·K -1 ), T represents an absolute temperature (K), I amp represents an average noise current (A) of a reproducing preamplifier, and Z represents impedance (Ω) of the reproducing preamplifier.
In each of the reproducing methods according to the first and second aspects of the present invention, it is possible to detect the reproducing beam passing through the recording layer by a detector having a self amplifying function for a photocurrent.
A reproducing apparatus according to a third aspect of the present invention, which is adapted to reproduce information from an optical recording medium provided with a recording layer reacting in a photon mode, comprises a light source for emitting a reproducing beam with constant power, power control means for damping the reproducing beam from the light source to a power level of P rep appearing in the above expression (I) or (II) for irradiating the recording layer with the reproducing beam, a lens system for converging the reproducing beam on the recording layer, and a detector for detecting the reproducing beam passing through the recording layer and being reflected by the optical recording medium.
In the apparatus according to the third aspect of the present invention, the detector is preferably formed by a detector having a self amplifying function for a photocurrent.
A reproducing method according to a fourth aspect of the present invention, which is adapted to reproduce information from an optical recording medium provided with a recording layer reacting in a photon mode, comprises a step of irradiating the recording layer with a reproducing beam at a power level being set within the range of P rep appearing in the above expression (II), a step of detecting the reproducing beam passing through the recording layer for reproducing recorded and unrecorded states, and a step of irradiating the recording layer with light of a wavelength band allowing substantially no absorption by a photon mode material contained in the recording layer as a servo beam thereby carrying out at least either focus servo control or tracking servo control.
A reproducing apparatus according to a fifth aspect of the present invention, which is adapted to form an optical recording medium provided with a recording layer reacting in a photon mode, comprises a first light source for emitting a reproducing beam with constant power, power control means for damping the reproducing beam from the first light source to a power level within the range of P rep appearing in the above expression (II) and irradiating the recording layer with the reproducing beam, a second light source for emitting light of a wavelength band allowing substantially no absorption by a photon mode material contained in the recording layer as a servo beam, beam synthetic means for synthesizing the reproducing beam and the servo beam and guiding the synthesized beam to the same optical path, a lens system for converging the synthesized beam on the recording layer, a photodetector having a self amplifying function for a photocurrent for detecting a component of the reproducing beam contained in the synthesized beam passing through the recording layer and being reflected from the optical recording medium, and a servo optical system and a servo circuit system for detecting a component of the servo beam contained in the synthesized beam passing through the recording layer and being reflected from the optical recording medium for carrying out at least either focus servo control or tracking servo control.
In the apparatus according to the fifth aspect of the present invention, wavelength selection means which substantially transmits the reproducing beam and does not substantially transmit the servo beam can be provided in an optical path of the reproducing beam component, contained in the synthesized beam reflected from the optical recording medium, for entering the photodetector.
The beam synthetic means in the apparatus according to the fifth aspect of the present invention can be formed by a dichroic mirror, for example. When the beam synthetic means is thus formed by a dichroic mirror, it is possible to form the overall apparatus so that this dichroic mirror reflects the servo beam contained in the synthesized beam which is reflected from the optical recording medium.
In the apparatus according to the fifth aspect of the present invention, further, another wavelength selection means which substantially transmits the servo beam and does not substantially transmit the other beam emitted from the second light source can be provided between the second light source and the beam synthetic means.
A reproducing method according to a sixth aspect of the present invention is adapted to optically record information in an optical recording medium whose recording layer has a reflectance of not more than 0.4 for a reproducing beam in an unrecorded state, and to reproduce the same. According to this method, a recorded portion of the recording layer preferably has a reflectance of not more than 0.7 for the reproducing beam. When the recording layer has a reflectance of not more than 0.2 for the reproducing beam in an unrecorded state, further, the recorded portion preferably has a reflectance of at least 0.4 for the reproducing beam.
A reproducing method according to a seventh aspect of the present invention is characterized in that a reproducing beam is prepared from squeezed light which has suppressed photon number fluctuation.
A reproducing method according to an eighth aspect of the present invention is characterized in that a reproducing beam is prepared from squeezed light which has suppressed photon number fluctuation, and applied to an optical recording medium at a power level which is set within a range of P rep (W) in the following expression (III) for reproducing information: ##EQU5## where SNR represents an S-N power ratio (PP/rms) required for the system, e represents an elementary electric charge of 1.6×10 -19 (C), B represents a bandwidth (Hz) of the system, η represents sensitivity (A/W) of a photodetector to a gain 1, γ represents pickup efficiency, R ave represents an average reflectance of the optical recording medium, and ΔR represents a difference in reflectance between recorded and unrecorded portions of the optical recording medium.
A light source for emitting the squeezed light which has suppressed photon number fluctuation can be formed by a semiconductor laser which is suppressed in spontaneous emission by a fine resonator structure and receives injection of an excitation current through a resistance of at least twice a differential resistance value.
According to the first aspect of the present invention, the power level of the reproducing beam is extremely reduced to increase the number of reproducing times. In general, such power reduction of the reproducing beam leads to an inferior S-N ratio. According to the present invention, the power of the reproducing beam is reduced to the minimum degree capable of ensuring a required S-N ratio in principle. Description is now made on this.
Noises appearing in an optical disk system include a disk noise which is caused by surface roughness of the disk, a laser noise which is caused by fluctuation of a laser beam, a thermal noise which is caused in a resistance part of a preamplifier system, and a shot noise which is caused by quantum-theoretical fluctuation of photons in the laser beam. The problems of the disk noise and the laser noise have already been technically solved and these noises have been suppressed to sufficiently low levels. On the other hand, the thermal noise and the shot noise, which are theoretical noises, cause problems in reduction of the power of the reproducing beam.
FIG. 1 shows relations between these noises and a signal level. Referring to FIG. 1, the axis of abscissas shows power of a reproducing beam, and the axis of ordinates shows outputs in units of dB. When the power of the reproducing beam is 1 mW, a signal is outputted at a reference level of 0 dB.
As clearly understood from FIG. 1, disk and laser noises are higher than heat and shot noises at a reproducing power level (up to 1 mW) employed for an ordinary optical disk, and a sufficient S-N ratio can be obtained since the signal level is sufficiently higher. When the reproducing power is reduced, the signal level and the disk and laser noises are lowered at 20 dB/dec., i.e., reduced by 20 dB when the reproducing power is 1/10. However, the thermal noise remains constant with no dependence on the reproducing power, as clearly understood from FIG. 1. On the other hand, the shot noise is reduced at 10 dB/dec. Consequently, factors for restricting the noises change targets from the disk and laser noises to the thermal noise and the shot noise in the vicinity of a point where the reproducing power is 10 -5 to 10 -6 . In particular, the thermal noise is so constant that the S-N ratio is remarkably reduced by the thermal noise at a reproducing power level of the order of several μW. However, this reduction is caused since a thermal noise current generated in a preamplifier resistance part reaches an unignorable level as compared with a photocurrent. It is possible to increase the photocurrent to prevent reduction of the S-N ratio caused by the thermal noise, by employing a photodetector having a self amplifying function.
Even if the thermal noise can be thus suppressed, the shot noise serves as a factor for restricting the S-N ratio at a very low power level of the order of several 10 nW. This shot noise is substantially caused by quantum-theoretical fluctuation, as hereinabove described. According to the present invention, the power of the reproducing beam is so set that the ratio of the signal level to the level of the shot noise is identical to an S-N ratio which is required for the system.
Assuming that P rep represents reproducing power (W), η represents photodetector sensitivity (A/W) corresponding to a gain 1, γ represents pickup efficiency, R ave represents an average reflectance of the optical recording medium, ΔR represents a difference in reflectance between recorded and unrecorded portions of the optical recording medium, B represents a bandwidth (Hz) of the system and e represents an elementary electric charge of 1.6×10 -19 (C), a shot noise average current I NS (A) is expressed as follows: ##EQU6##
Further, a peak signal output current I S (A) is expressed as I S =ηγP rep ΔR.
Hence, an S-N power ratio (PP/rms) is expressed as follows: ##EQU7##
Setting S/N appearing in the above expression as an S-N ratio which is required for the system, i.e., SNR, a solution as to P rep is expressed as follows: ##EQU8##
This value P rep represents the minimum possible power of the reproducing beam which can obtain the S-N ratio required for the system.
According to the first aspect of the present invention, therefore, it is possible to remarkably improve the number of reproducible times of the optical recording medium in a photon mode by reducing the power of the reproducing beam to a level in proximity to a prescribed value.
While the method according to the first aspect of the present invention is adapted to remarkably improve the number of reproducible times by reducing the reproducing power, the S-N ratio is lowered by a thermal noise. Such reduction of the S-N ratio can be prevented by employing a photodetector having a self amplifying function, such as an avalanche photodiode or a detector of a coherent photodetection system known as a homodyne/heterodyne system, for example, as hereinabove described.
In the method according to the second aspect of the present invention, such a photodetector having a Self amplifying function is adapted to reduce the power of the reproducing beam within a range capable of preventing reduction of the S-N ratio. Description is now made on this.
Assuming that an amplifier noise average current level of a preamplifier part is expressed as I amp =i amp ·B, where i amp represents noise density and B represents a bandwidth, a region where I S ≦I amp is set with respect to a shot noise current I S =(2eBI a ) 1/2 as follows: ##EQU9## where I a represents an average photocurrent of the photodetector with respect to a gain 1, which is expressed as I a =P rep ·R ave γη. Particularly when the amplifier noise level is governed by a thermal noise, thermal noise power N T =kTB is employed in place of I amp , to set the range as follows: ##EQU10## where P rep represents the reproducing power (W), e represents an elementary electric charge of 1.6×10 -19 (C), γ represents pickup efficiency, η represents photodetector sensitivity (A/W) with respect to a gain 1, k represents the Boltzman constant of 1.38×10 -23 J·K -1 , T represents an absolute temperature (K), and Z represents preamplifier impedance (Ω).
In combination with the above expression (I), therefore, it is understood that the power of the reproducing beam may be set at a level of P rep appearing in the following expression in the reproducing method employing the photodetector having a self amplifying function: ##EQU11##
When the power of the reproducing beam is set within the above range, it is possible to easily obtain a necessary S-N ratio, although the number of reproducible times is rather reduced as compared with the method according to the first aspect of the present invention.
FIG. 1 shows changes of the reproduced signal output and various noise outputs with respect to the power of the reproducing beam. Referring to FIG. 1, A denotes the lower limit P rep (min) of the power of the reproducing beam, which is expressed as follows: ##EQU12##
Similarly, B denotes the upper limit P rep (max) of the power of the reproducing beam, which is expressed as follows: ##EQU13##
Generally required is SNR of about 400 (electric power ratio PP/rms=26 dB), and the bandwidth is 1 to 20 MHz. Further, typical values are R ave =0.75, ΔR≈0.5, η≈0.4 (A/W), and γ=0.9. Hence, R rep (min) is about 0.5 to 10 nW, and P rep (max) is about several μW in consideration of employment at ordinary temperatures (up to 300K). According to the second aspect of the present invention, therefore, the range of P rep is about 0.5 nW to several μW.
The reproducing apparatus according to the third aspect of the present invention is an apparatus which can carry out the reproducing methods according to the first and second aspects of the present invention. In this reproducing apparatus, the power of the reproducing beam emitted from the light source is damped to the power level appearing in the above expression (I) or (II) with the power control means.
In such reduction of the power of the reproducing beam through the reproducing method according to the first or second aspect of the present invention, pickup efficiency is reduced when a part of the reflected reproducing beam entering the detector is separated and employed in an optical system for focus servo or tracking servo control. In this case, the S-N ratio is reduced or the optical power itself is reduced to instabilize the servo control since the reproducing beam having extremely low power is employed as a servo beam.
The reproducing method according to the fourth aspect of the present invention is adapted to solve such a problem. According to this method, a servo beam is prepared independently of the reproducing beam from light of a wavelength band allowing substantially no absorption by a photon mode material contained in the recording layer. Since the servo beam is thus prepared from the light of a wavelength band allowing substantially no absorption by the photon mode material, it is possible to arbitrarily set the power with no reaction of the photon mode material contained in the recording layer, for stabilizing the servo control. Further, reduction of the S-N ratio can be prevented since it is possible to prevent reduction of pickup efficiency with respect to the reproducing beam.
The reproducing apparatus according to the fifth aspect of the present invention is an apparatus which can carry out the reproducing method according to the fourth aspect. When the apparatus according to the fifth aspect of the present invention is employed, it is possible to remarkably improve the number of reproducible times of the optical recording medium without deteriorating stability of focus servo and/or tracking servo control as well as to obtain a reproduced output in an excellent S-N ratio.
The inventors have made deep study on optical density, changes of reflectances following photochromic reaction and the number of reproducible times, to find that the number of reproducible times can be further remarkably improved by optically recording information in an optical recording medium having a reflectance of not more than 0.4 for a reproducing beam in an unrecorded state of its recording layer and reproducing the same along the reproducing method according to the first or second aspect of the present invention.
The relation between the optical density and the reflectance is explained as follows. In the following description, all values described with no units are in MKSA unit systems.
The optical density, also called absorbance (Abs), is expressed as follows:
Abs≡εLC
where C respesents molar concentration (mol/l) of a photochromic material, L represents the thickness (cm) of a sample, and ε represents a molecular absorption coefficient (l/mol.cm) of the photochromic material.
In this case, absorptivity (Apt) of the sample is expressed as follows: ##EQU14##
A number dn of photons which are absorbed in a time dt when this sample is irradiated with light is expressed as follows: ##EQU15## where P represents irradiation power (W) of the light, υ represents c (light velocity)/λ (wavelength (mm) of the light), and h represents the Planck's constant.
In the number of photons absorbed by photochromic molecules, the number of reacting molecules is expressed as follows with a quantum yield k:
dN=-kdn
Considering the quantity of photochromic molecules contained in a unit volume and molar concentration, the following differential equation is obtained: ##EQU16## where S represents an area (cm 2 ) irradiated with the light, and Na represents the Avogadro number.
A change of variables C to T with T=exp{-2.3εLc} results in the following equation: ##EQU17##
While the above is a differential equation expressing the relation between an irradiation time t and transmissivity T, a similar change is attained when the irradiation power is increased in place of the irradiation time, for example. Therefore, this equation can be easily generalized to the following differential equation related to a parameter βP which is in proportion to an irradiation quantity (=P×t): ##EQU18##
While this equation is related to transmissivity, a similar equation can be guided also with respect to a reflectance R of an optical recording medium having a reflective layer, as follows: ##EQU19##
The factor 2 on the right side is caused by reciprocation of the light through the recording layer. It is assumed here that the reflectance of the reflective layer is substantially perfect (up to 100%).
This differential equation is applicable to recording and reproduction. In reproduction, P is replaced by a product n·P rep of the reproducing power P rep and the number n of reproducing times and reflectances R L and R H of unrecorded and recorded portions are supplied as initial conditions, so that a change of a difference ΔR=R H -R L between the reflectances upon repeated reproduction can be obtained by numerical calculation.
FIG. 14 illustrates a relation between the parameter βP and the reflectance R with extremely high optical concentration of an initial condition R 0 =0.01. While the parameter βP shown on the axis of abscissas is in proportion to an irradiation quantity (P·t)×material sensitivity (ε·k), this parameter can be regarded as indicating recording power in recording and the number of reproducing times in reproduction, ignoring concrete numerals.
FIGS. 15A to 17C illustrate relations between reflectance differences ΔR and parameters βP under various initial conditions of R H and R L . FIG. 15A shows a change of the reflectance difference in relation to a reflectance R L of 0.7 in an unrecorded state and a reflectance R H of 0.9 in a recorded portion. FIG. 15B shows a change of the reflectance difference in relation to a reflectance R L of 0.5 in an unrecorded state and a reflectance R H of 0.9 in a recorded portion. It is clearly understood from FIGS. 15A and 15B that the differences ΔR are monotonously and abruptly reduced as the parameters βP are increased, i.e., as information is repeatedly reproduced. When information recorded in such an optical recording medium is reproduced by the reproducing method according to the first or second aspect of the present invention, the optical recording medium has tens of thousands to hundreds of thousands of reproducible times up to reduction of the output by 3 dB.
FIGS. 16A and 16B show changes of reflectance differences in relation to a case of R L =0.35 and R H =0.6 and a case of R L =0.3 and R H =0.5. Dissimilarly to FIGS. 15A and 15B, the differences ΔR are not abruptly reduced with increase of the parameters βP, but initial inclinations are loose or substantially horizontal. This indicates that the numbers of reproducible times are improved several times as compared with those shown in FIGS. 15A and 15B.
FIGS. 17A to 17C show changes of reflectance differences in relation to higher optical concentration values with R L =0.1. Referring to FIG. 17A, the reflectance R H in the recorded portion is 0.3, i.e., less than 0.4. In this case, the reflectance is reduced after the same is temporarily remarkably increased by repetition of reproduction. Considering that the reproduced output is preferably as stable as possible, such increase in change of the reflectance is unpreferable. When the reflectance R H is set at 0.6 or 0.8 so that the recorded portion has a reflectance of at least 40%, it is possible to suppress such increase of the reflectance, as shown in FIG. 17B or 17C. Under the conditions shown in FIGS. 17A to 17C, information can conceivably be reproduced about millions of times, i.e., about twice or three times as compared with FIGS. 16A and 16B and about ten times as compared with FIGS. 15A and 15B.
According to the seventh aspect of the present invention, the reproducing beam is prepared from squeezed light having suppressed photon number fluctuation. Description is now made on the reason why noises are reduced through such light.
As hereinabove described, a shot noise is caused by quantum-theoretical fluctuation based on the uncertainty principle. A laser beam is quantum-mechanically explained in a quantum state called a "coherent state", with a photon number which is along Poisson distribution and fluctuation which is in proportion to the square root of the total photon number. Thus, the shot noise has been regarded as impossible to reduce since the same is based on quantum-mechanical fluctuation. However, the "squeezed state" has been recently discovered as a new quantum state of light. According to the uncertainty principle, the product ΔA×ΔB of fluctuation ΔA of a certain physical value A and fluctuation ΔB of another physical value B which is conjugated therewith cannot be smaller than the Planck's constant h. In other words, it is possible to reduce the fluctuation ΔA, if the fluctuation ΔB may be large. Assuming that the physical value A represents a photon number in light, the conjugate physical value B represents the phase of light waves. Therefore, the "coherent state" indicates a quantum state having photon number fluctuation which is equal to phase fluctuation, and the "squeezed state" indicates a quantum state having reduced photon number fluctuation and increased phase fluctuation. When light of a squeezed state having reduced photon number fluctuation and increased phase fluctuation is employed as a reproducing beam, therefore, it is possible to reduce noises below the shot noise level.
The light of a squeezed state having suppressed photon number fluctuation can be obtained by a semiconductor laser into which an excitation current is injected through a resistance of at least twice its differential resistance value, for example. Further, such light of a squeezed state can be generated by a method utilizing parametric oscillation with a nonlinear optical material, for example.
According to the eighth aspect of the present invention, light of a squeezed state having suppressed photon number fluctuation is employed as a reproducing beam at a power level within the range of P rep (W) appearing in the above expression (III). Therefore, it is possible to improve the number of reproducible times, while it is also possible to ensure a required S-N ratio even if the number of reproducible times is improved. Thus, such a reproducing method is useful when the number of reproducible times is to be preferentially improved as compared with the S-N ratio.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates relations between power of a reproducing beam and a signal output level and various noise levels;
FIG. 2 illustrates a molecular structure of a photochromic material employed in Example of the present invention and spectral reflectances of an optical recording medium formed by the photochromic material;
FIG. 3 is a sectional view showing the structure of the optical recording medium employed in Example;
FIG. 4 is a block diagram showing an embodiment of a reproducing apparatus according to the third aspect of the present invention;
FIG. 5 is a block diagram showing another embodiment of the reproducing apparatus according to the third aspect of the present invention;
FIG. 6 is a block diagram showing a first embodiment of a reproducing apparatus according to the fourth and fifth aspects of the present invention;
FIG. 7 illustrates a molecular structure of a photochromic material employed in Example and its absorption spectra;
FIG. 8 is a block diagram showing a second embodiment of the reproducing apparatus according to the fifth aspect of the present invention;
FIG. 9 is a spectral diagram showing transmissivity of a dichroic mirror employed in Example;
FIG. 10 illustrates a reproduction C-N ratio in Example employing no filter;
FIG. 11 illustrates a reproduction C-N ratio in Example employing a filter;
FIG. 12 is a model diagram showing a third embodiment of the reproducing apparatus according to the fifth aspect of the present invention;
FIG. 13 is a model diagram showing a fourth embodiment of the reproducing apparatus according to the fifth aspect of the present invention;
FIG. 14 illustrates a relation of an irradiation quantity and a reflectance level to a photon mode medium;
FIGS. 15A and 15B illustrate relations between reflectances R L and R H in unrecorded states and recorded portions of recording layers with respect to reproducing beams and parameters βP serving as measures of numbers of repeated reproducing times;
FIGS. 16A and 16B illustrate relations between reflectances R L and R H unrecorded states and recorded portions of recording layers with respect to reproducing beams and parameters βP serving as measures of numbers of repeated reproducing times;
FIGS. 17A to 17C illustrate relations between reflectances R L and R H in unrecorded states and recorded portions of recording layers with respect to reproducing beams and parameters βP serving as measures of numbers of repeated reproducing times;
FIG. 18 illustrates spectral reflectances of an optical recording medium having a reflectance R L of 0.5;
FIG. 19 illustrates spectral reflectances of an optical recording medium having a reflectance R L of 0.13;
FIG. 20 illustrates a relation between a number of reproducing times and an amount of signal level reduction in comparative example 1-1;
FIG. 21 illustrates a relation between a number of reproducing times and an amount of signal level reduction in Example 1-1;
FIG. 22 illustrates a relation between a number of reproducing times and an amount of signal level reduction in comparative example 2-1;
FIG. 23 illustrates a relation between a number of reproducing times and an amount of signal level reduction in Example 2-1;
FIG. 24 illustrates a relation between a number of reproducing times and an amount of signal level reduction in Example 2-2;
FIG. 25 illustrates a relation between a number of reproducing times and an amount of signal level reduction in Example 3-1;
FIG. 26 illustrates a relation between a number of reproducing times and an amount of signal level reduction in Example 3-2;
FIG. 27 illustrates a relation between a number of reproducing times and an amount of signal level reduction in comparative example 3-1;
FIG. 28 illustrates a relation between a number of reproducing times and an amount of signal level reduction in Example 4-1;
FIG. 29 illustrates a relation between a number of reproducing times and an amount of signal level reduction in Example 5-1;
FIG. 30 illustrates a relation between a number of reproducing times and an amount of signal level reduction in Example 5-2;
FIG. 31 illustrates a relation between a number of reproducing times and an amount of signal level reduction in Example 6-1; and
FIG. 32 is a block diagram showing an embodiment of a reproducing apparatus for carrying out a reproducing method according to the seventh aspect of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 2 illustrates the molecular structure of a diarylethene photochromic material employed in Example of the present invention, and reflectances of recorded and unrecorded portions of the photochromic material. When the photochromic material is irradiated with light in the vicinity of 460 nm in wavelength in a state A having an absorption maximum in the vicinity of the wavelength of 460 nm, this photochromic material is converted to a state B having a new absorption maximum in the vicinity of a wavelength of 600 nm. When irradiated with light of about 550 to 700 nm in wavelength in the state B, on the other hand, the photochromic material returns to the original state A. Therefore, it is possible to record information by previously bringing this photochromic material into the state B and irradiating the same with a laser beam of about 600 nm in wavelength with strong power. Further, it is possible to reproduce the information by irradiating the photochromic material with a reproducing beam of very low power and detecting a change in reflectance in the same wavelength band.
25 percent by weight of this photochromic material was mixed into polyvinyl butyral resin. This mixture was dissolved in a mixed solution of anone and benzene, spin-coated on a glass disk substrate and dried, to form a recording layer of about 1 μm in thickness. Then, an Ag film was formed thereon by vacuum deposition, to define a reflective film. FIG. 3 is a sectional view showing the obtained optical recording medium. A recording layer 801 is formed on a glass disk substrate 800, and an Ag reflective film 802 is formed thereon. This optical recording medium exhibited a reflectance of R ave ≈0.75 at λ=630 nm with ΔR≈0.5, as shown in FIG. 2.
A recording method according to the first aspect of the present invention and a corresponding recording apparatus according to the third aspect of the present invention are now described.
FIG. 4 is a model diagram showing an embodiment of the reproducing apparatus according to the third aspect of the present invention. Referring to FIG. 4, a reproducing beam which is emitted from a semiconductor laser 1 passes through a collimator lens 5, a power control element 6, a polarized beam splitter 2, a quarter-wave plate 3 and an objective lens 4, to be applied to an optical recording medium 8. The reproducing beam passing through a recording layer and being reflected by a reflective film passes again through the objective lens 4 and the quarter-wave plate 3, to be reflected by the polarized beam splitter 2 and detected by a photodetector 7 through a lens. According to this embodiment, the semiconductor laser 1 is prepared from that emitting a laser beam of 630 nm in wavelength. On the other hand, the photodetector 7 is prepared from an avalanche photodiode having a self amplifying function for a photocurrent. While the reproducing beam is set at an extremely low power level of not more than 1 μW according to the present invention, it is difficult to stably drive light which is emitted from a semiconductor laser with such very low power. According to this embodiment, therefore, the semiconductor laser 1 is set to emit power of about 1 mW at a constant level, so that the power of the reproducing beam is damped to a level of several 10 nW, i.e., not more than 1 μW, by the power control element 6 such as an ND filter.
In order to record information in an optical recording medium with the apparatus shown in FIG. 4, the power of the semiconductor laser 1 may be increased to a high level of about 10 mW, for example, to modulate the intensity in response to a recording signal, or the power control element 6 may be removed from the optical path in recording.
Further, the power control element 6 may be prepared from a liquid crystal modulator etc. which can change transmissivity in response to an external recording/reproducing mode switching signal.
FIG. 5 shows an apparatus which is provided with such a power control element 6. In such an apparatus, the quantity of light reaching an avalanche photodiode (APD) is increased in a recording mode. In order to prevent an overcurrent from flowing, therefore, it is preferable to provide a setting circuit for reducing a reverse bias voltage which is applied to the APD and lowering its gain in a recording mode. Referring to FIG. 5, such a circuit is provided as an APD reverse bias setting part. Each of the apparatuses shown in FIGS. 4 and 5 was employed for reproducing information. Under conditions of pickup efficiency γ of 0.6, sensitivity η of the APD of 0.4 (A/W) with respect to a gain 1, a system bandwidth of 10 MHz and a required S-N ratio of 26 dB, the reproducing beam has power of 16 nW from the above expression (I). The reproducing beam was set at such a very low power level through the power control element 6, to reproduce information. Consequently, an excellent S-N ratio was obtained with an APD gain of 100 times, and the information was reproduced 150,000 times when a signal output was reduced by 3 dB.
For the purpose of comparison, information was reproduced with a reproducing beam at a power level of 1 mW. In this case, the information was reproduced only 10 times when the reproduced output was reduced by 3 dB.
It is clearly understood from the above that the number of reproducible times can be improved at least 10,000 times by employing the reproducing method according to the first aspect of the present invention.
Although the photodetector having a self amplifying function is prepared from an APD in each of the aforementioned embodiments, the present invention is not restricted to this but a photodetector of a coherent optical detection system can also be employed.
A reproducing method according to the second aspect of the present invention and a corresponding reproducing apparatus according to the third aspect are now described.
The reproducing apparatus shown in FIG. 4 was employed with pickup efficiency γ of 0.9.
A reproduced signal was evaluated as follows: The system bandwidth was set at 10 MHz, and a signal of 1 MHz was recorded and reproduced to measure a C-N ratio at RBW=30 kHz. This C-N ratio was converted to an S-N ratio along S-N ratio=C-N ratio×(30 kHz/10 MHz). As to a photodetector for such reproduction, a generally employed Si-PIN.PD and an avalanche photodiode (Si-APD) were employed and compared with each other. Numbers of reproducible times were compared through points where reproduced outputs were reduced by 3 dB.
When the signal was reproduced with reproducing power of 10 nW, the apparatus exhibited an extremely inferior S-N ratio of 4 dB through the photodetector of PIN. PD. When the photodetector was replaced by the APD, on the other hand, the S-N ratio was improved to 27 dB. At this time, it was possible to reproduce the signal 500,000 times.
Then, the signal was reproduced with reproducing power of 800 nW, whereby the apparatus exhibited a relatively excellent S-N ratio of 21 dB through PIN. PD. When the photodetector was replaced by the APD, the S-N ratio was further improved to 28 dB. At this time, it was possible to reproduce the signal about 10,000 times.
When the signal was reproduced with reproducing power of 5 μW, the apparatus exhibited the same S-N ratio of 27 dB through both of the PIN. PD and the APD, substantially with no effect of improvement in S-N ratio through employment of the APD. At this time, it was possible to reproduce the signal about 2,000 times.
When the signal was reproduced with reproducing power of 0.1 mW, further, the S-N ratio remained at 27 dB through both of the PIN. PD and the APD. However, the number of reproducible times was reduced to about 50.
As clearly understood from the above results, a photodetector having a self amplifying function such as an APD attains an effect of improvement in S-N ratio when the reproducing power is not more than several μW. In consideration of improvement in number of reproducible times, the reproducing power is preferably closer to the lower limit P rep (min) than the upper limit P rep (max).
A reproducing method according to the fourth aspect of the present invention and a reproducing apparatus according to the fifth aspect of the present invention are now described.
FIG. 6 is a model diagram showing a first embodiment of the reproducing apparatus according to the fifth aspect of the present invention. In the reproducing apparatus shown in FIG. 6, a reproducing optical system A is so combined with a servo optical system B that a reproducing beam from the former is synthesized with a servo beam from the latter by a dichroic mirror 9, which is a beam synthesis means, and the synthesized beam is converged on a optical recording medium 8 by an objective lens 4.
FIG. 7 illustrates absorbance levels of a 2-(1,2-dimethyl-3-indolyl)-3-(2,3,5-trimethyl-3-thienyl) maleic anhydride, which is employed as a photochromic material in the optical recording medium 8, at respective wavelengths. These spectra are in correspondence to FIG. 2, which shows reflectances of the same compound. As clearly understood from FIG. 7, this photochromic material has a relatively large absorption change in the vicinity of a wavelength of 630 nm. Thus, a reproducing light source 1 can be prepared from a visible light emitting semiconductor laser which can emit a laser beam of about 630 nm in wavelength.
Referring again to FIG. 6, light emitted from the light source 1 is shaped by a collimator lens 5, and converted to a reproducing beam of very low power by a power control element 6. The power control element 6 can be formed by an ND filter, for example. The power of the reproducing beam emitted from the light source 1, which is of the order of several mW, is extremely damped by such an ND filter which is 1/1,000,000 to 1/1000 in transmissivity. The reproducing beam whose power is damped by the power control element 6 passes through a polarized beam splitter 2 and a quarter-wave plate 3 and is reflected by the dichroic mirror 9, to be converged on the optical recording medium 8 through the objective lens 4.
The reproducing beam passing through a recording layer and is reflected by a reflective film backwardly travels along the same optical path, and is reflected by the polarized beam splitter 2, to be photoelectrically converted and detected by a photodetector 7. This photodetector 7 is formed by an avalanche photodiode having a self-amplifying function for a photocurrent, as described above.
On the other hand, a servo light source 10 is formed by a near infrared semiconductor laser of 780 nm in wavelength, which is in a wavelength band allowing no absorption by the photochromic material. The light source 10 emits a beam with power of about 1 mW, in order to stabilize servo control. This beam is shaped by a collimator lens 11, passes through a polarized beam splitter 12 and a quarter-wave plate 13, and is transmitted through the dichroic mirror 9 to be converged on the optical recording medium 8 through the objective lens 4. The servo beam which is reflected in the optical recording medium 8 backwardly travels along the same optical path and is reflected by the polarized beam splitter 12, to be converted to a focus error signal or a tracking error signal by a focus/tracking error detection optical system. This focus/tracking error detection optical system can be prepared from a well-known system. A focus servo/tracking servo control circuit drives the objective lens 4 on the basis of the error signal, to carry out focus servo or tracking servo control.
FIG. 8 is a model diagram showing a second embodiment of the reproducing apparatus according to the fifth aspect of the present invention. This embodiment is different from that shown in FIG. 6 in a point that a filter 14 is provided between a polarized beam splitter 2 and a photodetector 7 in a reproducing optical system A. In other structure, this embodiment is identical to that shown in FIG. 6, and hence corresponding parts are denoted by the same reference numerals to omit redundant description. The filter 14 is adapted to eliminate light in a wavelength band of a servo beam, to transmit only light in a wavelength band of a reproducing beam. The reason why such a filter is provided is now described.
When a reproducing beam of the nW order is employed, the quantity of light which is reflected from an optical recording medium 8 to reach the photodetector 7 is also of the nW order. On the other hand, a semiconductor laser 10, which serves as a servo light source, has intensity of the order of 1 mW, and intensity of the servo beam which is reflected by the optical recording medium 8 to enter the dichroic mirror 9 is also of the order of about 1 mW. The dichroic mirror 9 has a property of reflecting light of the wavelength (λ=630) of the reproducing beam while transmitting light of the wavelength (λ=780 nm) of the servo beam. However, while its transmissivity for the light of λ=630 nm in wavelength is substantially 0% as shown in FIG. 9, it is difficult to transmit the light of λ=780 nm in wavelength by 100%, and about several % of this light is reflected to enter the reproducing optical system A. If the apparatus shown in FIG. 8 is provided with no filter 14, a servo beam having intensity of about several 10 μW inevitably enters the photodetector 7 due to the reflectance of several % of the dichroic mirror 9. This forms light of 10,000 times the reproducing beam in intensity, leading to not only increase of a dc component in a reproduced output current but remarkable influence of noises caused by the servo beam.
In order to solve this problem, the filter 14, such as an interference filter which transmits the reproducing beam with extremely low transmissivity for the servo beam, may be provided in any portion between the dichroic mirror 9 and the photodetector 7. According to this embodiment, therefore, the filter 14 is provided between the polarized beam splitter 2 and the photodetector 7.
FIG. 10 illustrates a reproduction C-N ratio of an apparatus provided with no filter, with a reproducing beam of 10 nW in power and a servo beam of 10 mW in power. As shown in FIG. 10, the apparatus provided with no filter exhibits an extremely inferior C-N ratio of 10 dB.
On the other hand, FIG. 11 shows a reproduction C-N ratio of an apparatus provided with a filter. As shown in FIG. 11, this apparatus exhibits an excellent C-N ratio of about 40 dB.
FIG. 12 is a model diagram showing a third embodiment of the reproducing apparatus according to the fifth aspect of the present invention. This embodiment shows an optical system which solves the aforementioned problem by changing a dichroic mirror 9 in design. Since the dichroic mirror 9 can be designed substantially at 100% with respect to reflection as hereinabove described, a servo beam is reflected by the dichroic mirror 9 to be converged on an optical recording medium in an optical system according to this embodiment. Due to such a structure, it is possible to extremely reduce an amount of the servo beam entering a reproduction optical system. Further, it is possible to reduce the cost since no filter is required. However, the S-N ratio is slightly reduced due to loss of a reproducing beam caused in the dichroic mirror 9.
FIG. 13 is a model diagram showing a fourth embodiment of the reproducing apparatus according to the fifth aspect of the present invention. This embodiment is different from that shown in FIG. 6 in a point that a filter 15 is provided between a collimator lens 11 and a polarized beam splitter 12 in a servo optical system B. This filter 15 is adapted to eliminate light emitted from a semiconductor laser light source 10, which is at a wavelength other than that of a servo beam. This filter 15 is provided for the following reason:
The light emitted from the semiconductor laser light source 10 includes a laser beam generated by laser oscillation at a near infrared wavelength and a non-laser light component generated by spontaneous emission, which is lower in intensity than the laser. In general, a non-laser light component has a wavelength of a visible region, which is shorter than that of a laser light component. Even servo control is carried out through a laser beam of a wavelength band allowing no absorption by the photochromic material, therefore, photochromic molecules may cause reaction to damage recorded information due to the non-laser light component generated by spontaneous emission. In order to solve this problem, the filter 15 is provided in this embodiment to transmit only the laser light component and eliminate the non-laser light component in the light emitted from the light source 10.
While each of the embodiments shown in FIGS. 8 and 13 employs a filter as wavelength selection means, such a filter may be replaced by an element such as a polarized beam splitter or a quarter-wave plate which is coated with a dielectric multilayer film and provided with a function similar to that of the filter.
Description is now made on Experimental Example of optical recording media having values R L shown in FIG. 3, which were prepared from the diarylethene photochromic material shown in FIG. 7 with reflective layers of Ag and recording layers containing polystyrene to be subjected to measurement of numbers of reproducible times.
The overall surface of each optical recording medium was previously sufficiently irradiated with blue light and brought into the state shown by the solid line in FIG. 7. Then the optical recording medium was irradiated with an HeNe laser beam of 633 nm in wavelength, the intensity of which was modulated with relatively strong power, for optically recording information. Thereafter the medium was dc-irradiated with light of the same wavelength with very low reproducing power, for detecting a change of the reflectance level and reproducing the information.
FIG. 18 illustrates spectral reflectances of the optical recording medium of R L =0.5 having relatively low optical concentration, and FIG. 19 illustrates those of an optical recording medium of R L =0.13 having relatively high optical concentration.
Photoelectric conversion was performed through an avalanche photodiode having a self amplifying function for a photocurrent, to carry out current-to-voltage conversion of an amplified photocurrent with a high band/low bias current operational amplifier.
In an optical system employed for such measurement, the avalanche photodiode had sensitivity of η=0.4 (A/W) with respect to a gain 1, and pickup efficiency, indicating a rate of reflected light from the medium coupling with the photodiode, was set as γ=0.8.
A linear velocity of a disk was set at 5 m/sec. in all measurement. Assuming that the minimum recorded portion is about 1.2 μm in length with a reproducing laser spot diameter of about 1.2 μm, the system has a bandwidth W corresponding to about 2.1 MHz. While the length of the minimum recorded portion may be smaller than the above value, the bandwidth may be derived from the length of the recorded portion in this case.
Assuming that a required S-N ratio is 26 dB, a required C-N ratio measured with RBW of 30 kHz, resulting from S-N ratio=C-N ratio×(30 kHz/w), is as follows:
C-N ratio=26 dB+18 dB=44 dB
The C-N ratio was measured with respect to a recorded signal of 1 MHz.
Description is now made on Experimental Examples of optical recording media having various optical concentration levels to be subjected to measurement of numbers of reproducible times.
<EXAMPLE 1 >
Information was optically recorded in an optical recording medium having an initial reflectance R L of 0.79 at γ=633 nm, with recording power of 10 mW. At this time, a recorded portion exhibited a reflectance R H of about 1, with a reflectance change ΔR of 0.21 and an average reflectance R ave of 0.90.
Comparative Example 1-1
The information was reproduced at P rep =0.5 mW, which is a lower limit of reproducing power of about 1/5 to 1/20 of recording power generally employed in a heat mode optical recording medium etc. The resultant initial C-N ratio was 49 dB. FIG. 20 shows C level reduction in repetition. As clearly understood from FIG. 20, it was possible to reproduce the information only three times.
EXAMPLE 1-1
The information was reproduced with reproducing power P rep =18 nW, which was within the range according to the first aspect of the present invention. The resultant initial C-N ratio was 48 dB. FIG. 21 shows C level reduction in repeated reproduction. As clearly understood from FIG. 21, it was possible to reproduce the information about 50,000 times.
<Example 2>
An optical recording medium having an initial reflectance R L of 0.5 at λ=633 nm, to record information with recording power of 10 mW. This optical recording medium was similar to that shown in FIG. 18. A recorded portion exhibited a reflectance R H f 0.98, with a reflectance change ΔR=0.48 and an average reflectance R ave of 0.74.
Comparative Example 2-1
The information was reproduced with reproducing power P rep of 0.5 mW, to result in an initial C-N ratio of 49 dB. FIG. 22 shows C level reduction in repeated reproduction. As clearly understood from FIG. 22, it was possible to reproduce the information only four times.
EXAMPLE 2-1
The information was reproduced with reproducing power P rep of 2.6 nW, which was within the range according to the first aspect of the present invention. The resultant initial C-N ratio was 44 dB. This C-N ratio satisfied the aforementioned value of the required C-N ratio. FIG. 23 shows C level reduction in repetition. As clearly understood from FIG. 23, it was possible to reproduce the information 480,000 times.
EXAMPLE 2-2
The information was reproduced with reproducing power P rep of 20 nW, which was within the range according to the second aspect of the present invention. The resultant initial C-N ratio was 49 dB. FIG. 24 shows C level reduction in repeated reproduction. As clearly understood from FIG. 24, it was possible to reproduce the information 70,000 times.
Comparative Example 2-2
The information was reproduced with reproducing power P rep of 1.3 nW, which was lower than the ranges according to the first and second aspects of the present invention. The resultant initial C-N ratio was 40 dB. This value did not satisfy the value of the aforementioned required C-N ratio.
Experimental Examples according to the sixth aspect of the present invention are now described.
<EXAMPLE 3>
Information was recorded in an optical recording medium having an initial reflectance R L of 0.25 at λ=633 nm, with recording power of 5 mW. At this time, a recorded portion exhibited a reflectance R H of 0.78, with a reflectance change ΔR of 0.51 and an average reflectance R ave of 0.51.
EXAMPLE 3-1
The information was reproduced with reproducing power P rep of 1.6 nW, which was within the range according to the first aspect of the present invention. The resultant initial C-N ratio was 44 dB. FIG. 25 shows C level reduction in repeated reproduction. As clearly understood from FIG. 25, it was possible to reproduce the information 2,000,000 times. This number of reproducible times was greater than those in Examples 1-1, 2-1 and 2-2.
EXAMPLE 3-2
The information was reproduced with reproducing power P rep of 12 nW, which was within the range according to the second aspect of the present invention. The resultant initial C-N ratio was 47 dB. FIG. 26 shows C level reduction in repeated reproduction. As clearly understood from FIG. 26, it was possible to reproduce the information 250,000 times.
Comparative Example 3-1
The information was reproduced with reproducing power of 0.25 mW, which was 1/20 of the recording power. The resultant initial C-N ratio was 49 dB. However, it was possible to reproduce the information only 13 times, as shown in FIG. 27.
<EXAMPLE 4>
Information was optically recorded in the optical recording medium, employed in Example 3, having an initial reflectance R L of 0.25 at λ=633 nm, with recording power of 3 mW. At this time, a recorded portion exhibited a reflectance R H of 0.57, with a reflectance change ΔR of 0.32 and an average reflectance R ave of 0.41.
EXAMPLE 4-1
The information was reproduced with reproducing power P rep of 3.4 nW, which was within the range according to the first aspect of the present invention. The resultant initial C-N ratio was 44 dB. FIG. 28 shows C level reduction in repetition. It was possible to reproduce the information 1,300,000 times. While this number of reproducible times was slightly reduced as compared with 2,000,000 times in Example 3-1, a reproducing photodetector may have a small bias voltage in this case since the reproducing power was increased by at least twice and the structure of the detection circuit system can be further simplified since an amplifier system may have a small gain.
<EXAMPLE 5>
Information was optically recorded in an optical recording medium having an initial reflectance R L of 0.13 at λ=633 nm with recording power of 4 mW. At this time, a recorded portion exhibited a reflectance R H of 0.47, with a reflectance change ΔR of 0.34 and an average reflectance R ave of 0.30.
EXAMPLE 5-1
The information was reproduced with reproducing power P rep of 2.1 nW, which was within the range according to the first aspect of the present invention. The resultant initial C-N ratio was 44 dB. FIG. 29 shows C level reduction in repeated reproduction. As clearly understood from FIG. 29, the signal level was slightly improved by about 2 dB and then reduced along repetition of reproduction, and it was possible to reproduce the information 3,000,000 times.
EXAMPLE 5-2
The information was reproduced with reproducing power P rep of 15 nW, which was within the range according to the second aspect of the present invention. The resultant initial C-N ratio was 48 dB. FIG. 30 shows C level reduction in repeated reproduction. As clearly understood from FIG. 30, the signal level was temporarily improved by about 2 dB and thereafter reduced along repetition of reproduction. It was possible to reproduce the information 400,000 times.
<EXAMPLE 6>
Information was optically recorded in the optical recording medium employed in Example 5, with recording power changed from 4 mW to 2 mW. At this time, a recorded portion exhibited a reflectance R H of 0.18, with a reflectance change ΔR of 0.06 and an average reflectance R ave of 0.16.
EXAMPLE 6-1
The information was reproduced with reproducing power P rep of 37 nW, which was within the range according to the first aspect of the present invention. The resultant initial C-N ratio was 44 dB. FIG. 31 shows C level reduction in repeated reproduction. As shown in FIG. 31, it was possible to reproduce the information 230,000 times, while the signal level was remarkably improved by 5.5 dB and thereafter reduced with repetition of reproduction. In consideration of the fact that the reproduced signal level is preferably as stable as possible, Examples 5-1 and 5-2 are more preferable.
In addition to the aforementioned Examples, recording power was experimentally controlled for changing the reflectance R H of the recorded portion to various levels, to find that such remarkable increase of the C level is not caused when R H is at least 0.4. It was further proved that such remarkable increase of the C level is recognized in an optical recording medium having an initial reflectance R L of less than 0.2.
When information is reproduced from an optical recording medium having an initial reflectance R L exceeding 0.4 with very low power according to the first or second aspect of the present invention, the information can be reproduced at the order of 100,000 times, as hereinabove described. When information is reproduced from an optical recording medium having an initial reflectance R L of not more than 0.4 with very low power according to the first or second aspect of the present invention, on the other hand, it is possible to reproduce the information at the order of 1,000,000 times.
Particularly when information is recorded in an optical recording medium having a reflectance R L of not more than 0.4 with recording power being so controlled that a recorded portion has a reflectance R H of not more than 0.7, it is possible to reduce burdens on a reproducing photodetector, an amplifier circuit and the like.
As to an optical recording medium having a reflectance R L of not more than 0.2, it is possible to suppress remarkable increase of a signal level following reproduction thereby obtaining a stable signal level by recording information with conditions being so set that a recorded portion has a reflectance R H of at least 0.4.
While the reflective layer of the optical recording medium is prepared from Ag having a high reflectance in each of the aforementioned embodiments, the present invention is also applicable to a reflective layer of aluminum or chromium, which has a reflectance of not more than 1. When the reflective layer has a reflectance of not more than 1, a reflectance R of the optical recording medium with respect to absorbance Abs of a recording layer and a reflectance R 0 of the reflective layer can be expressed as follows:
R=e.sup.-2.3×Abs R.sub.0 e.sup.-2.3×Abs
where the absorbance Abs is indicated as a value with respect to single passage of light through the recording layer.
When the reflective layer has a reflectance R 0 of not more than 1, the present invention can be applied along the aforementioned expression.
When the reflectance R 0 of the reflective layer is regarded as 1, the reflectance R is expressed as follows:
R=e.sup.-2×2.3×Abs
Description is now made on an embodiment employing squeezed light having suppressed photon number fluctuation as a reproducing beam according to the seventh aspect of the present invention.
FIG. 32 is a block diagram showing a reproducing apparatus for carrying out the reproducing method according to the seventh aspect of the present invention. Referring to FIG. 32, numeral 31 denotes a semiconductor laser and numeral 32 denotes a resistance, while numeral 33 denotes a driving power source. The resistance 32 is set to have a value of at least twice the differential resistance value of the semiconductor laser 31, so that an excitation current is injected into the semiconductor laser 31. Due to such setting, a reproducing beam emitted from the semiconductor laser 31 enters a squeezed state having suppressed photon number fluctuation.
According to this embodiment, further, spontaneous emission of the semiconductor laser 31 is suppressed by a fine resonator structure.
The technical content of such a semiconductor laser having a fine resonator structure is disclosed in the 38th Joint Lecture Meeting (Spring 1991), the Japan Society of Applied Physics, 30P-F-7 to 9, the 39th Joint Lecture Meeting (Spring 1992), the Japan Society of Applied Physics, 29P-C-14, the 53rd Scientific Lecture Meeting (Autumn 1992), the Japan Society of Applied Physics, 16a-V-3, "Fine Resonator Laser: Status Quo and Prospect" by Hiroyuki Yokoyama, Applied Physics, Vol. 61, No. 9 (1992), pp. 890 to 901, and the like. In particular, the fine resonator structure is characterized in that laser oscillation can be set at a very low threshold value.
An ordinary semiconductor laser has an oscillation threshold value of about several 10 mA, and hence it is impossible to stably control its laser beam by an injection current with very low power of the order of not more than several μW. In a semiconductor laser whose spontaneous emission is suppressed by the fine resonator structure, on the other hand, it is possible to stably control laser power below the μW order with an injection current of the μA order by controlling a reflectance R on an end surface of the resonator.
Referring to FIG. 32, a reproducing beam which is emitted from the semiconductor laser 31 serving as a light source is shaped by a collimator lens 25 and passes through a polarized beam splitter 24 and a quarter-wave plate 23, to be converged on a photon mode medium 21, such as a photochromic medium, by an objective lens 22. The reflected beam is intensity-modulated in response to recorded information, and again passes through the objective lens 22, the quarter-wave plate 23 and the polarized beam splitter 24, to enter a photodetector 27 through a lens 26. While such a photodetector is generally prepared from a PIN photodiode, this photodetector 27 is preferably prepared from that having a self amplifying function for a photocurrent since a reproduction S-N ratio is reduced by a thermal noise in a PIN photodiode when very low reproducing power is employed as in the present invention. According to the present invention, the photodiode 27 is prepared from an avalanche photodiode, to which a high reverse bias current (several 10 to 100 V) 28 is applied. The detected photocurrent is converted to a voltage by a current-to-voltage converting part which is formed by a combination of a differential amplifier 29 and a resistance 30, to provide a reproduced output.
In order to prevent breakage of the squeezed state caused by optical loss, loss of the optical system is preferably reduced to the minimum while quantum efficiency in photoelectric conversion of the photodetector 27 is preferably increased to the maximum. Further, the optical recording medium 21 preferably has a high average reflectance. In order to reduce the loss of the optical system, further, the respective optical elements are preferably provided with nonreflective coatings.
Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims. | A technique for improving a number of reproducible times in reproduction of information from an optical recording medium having a recording layer which reacts in a photon mode. The power of a reproducing beam is set in proximity to P rep (W) appearing in the following expression (I) or within a range of P rep (W) appearing in the following expression (II): ##EQU1## In order to improve an S-N ratio, squeezed light having suppressed photon number fluctuation is employed as a reproducing beam at need. If improvement of the number of reproducible times is in preference to improvement of the S-N ratio, such squeezed light having suppressed photon number fluctuation is employed as a reproducing beam with power which is set within a range of P rep (W) appearing in the following expression (III): ##EQU2## | 6 |
BACKGROUND OF THE INVENTION
This invention relates to compounds having a physiological cooling effect on the skin and on the mucous membranes of the body, particularly those of the mouth, nose and throat.
Menthol exists abundantly in nature and has been known for a long time as a physiological cooling compound. It is well established that the “cooling” effect of menthol is a physiological effect due to the direct action of menthol on the nerve ends of the human body responsible for the detection of hot or cold and is not due to latent heat of evaporation or dissolution. Menthol has been used widely in cigarettes, cosmetics, toothpastes, chewing gum, sweets, and medicines. Disadvantages of menthol include its strong “stinging” smell, bitter taste, burning sensation in high concentration and high volatility. These undesirable properties limit applications of menthol to some extent.
Since 1960's, researchers have been working on discovering synthetic substitutes of menthol, which possess low volatility and have almost no odor or taste.
The easiest and most straightforward direct modification of l-menthol is to make menthyl esters, such as, menthyl acetate, menthyl lactate (German Patent 2,608,226), saccharide ester of menthol (Swiss Patent 484,032), menthyl 2-hydroxybutyrate (French Patent 2,577,922), menthyl monomenthyl succinate (U.S. Pat. No. 3,111,127), monomenthyl glutarate (U.S. Pat. No. 6,365,215), menthyl hydroxyethyl carbonate (U.S. Pat. No. 3,419,543), etc. Another way to take advantage of hydroxyl group in menthol is to incorporate it to an ether linkage, e.g., menthyl glyceryl ether (U.S. Pat. No. 4,459,425). Ketals of menthone, such as, menthone glycerin ketal can be made readily and it is proven to be a coolant (German Patent 4,266,043 and U.S. Pat. No. 5,266,592) because of the paramenthane moiety in the structure. Menthol analogs are equally attractive, such as, isopulegol (U.S. Pat. No. 5,773,410) and paramenthane-3,8-diol (U.S. Pat. No. 5,959,161). Both compounds are obtained by cyclization of citronellal.
A large variety of compounds without paramenthane structure have also been found to possess cooling property, for instance, cyclohexanol derivatives (German Patent 2,317,000), cyclic secondary and tertiary alcohols (GB Patent 1,404,596), alkylmethanols (German Patent 2,439,770), trialkylphospine oxides (German Patent 2,345,156), cyclic and acyclic sulfoxides and sulfones (German Patent 2,334,985 and German Patent 2,336,495) all show cooling effect, but the strength of the cooling effect varies.
Amides, as cooling agents, might be the most important group of compounds. N,N-dimethyl 2-ethylbutanamide and 2,2-deimethylpropanamide (French Patent 1,572,332) were found to possess physiological cooling effect decades ago. Later on, a large number of cyclic amides with 5- to 11-membered rings (GB Patent 1,489,359, GB Patent 1,489,359, German Patent 2,624,504 and U.S. Pat. No. 4,296,093) were identified as cooling agents. Later, menthol derived amides (U.S. Pat. No. 4,150,052) were discovered as coolants by Wilkinson Sword company. Among these amides, N-ethyl menthane-carboxamide (WS-3) was successfully commercialized.
In 1972 Wilkinson Sword also discovered another attractive series of acyclic amides (2,3-dimethyl-2-isopropylbutyramides, GB 1,421,744), which interestingly do not show much similarity in structure to menthol or menthol derivatives. Of all these amides of highly branched, tertiary acyclic carboxylic acids, N,2,3-trimethyl-2-isopropylbutyramide (WS-23) has been successfully commercialized. WS-23 possesses a strong cooling effect and a good taste quality.
A new current trend is searching for convenient liquid sellable forms of cooling agents with little or no solvent. To find eutectic mixtures of existing cooling agents requires cooling compounds with low melting points and even liquid cooling compounds with comparable cooling effect. Primary amides, e.g. WS-23, with high enough molecular weight are normally highly crystalline due to the intermolecular hydrogen bonding in the structure. Introducing functional groups with oxygen atom in either ether linkage or terminal hydroxyls will promote intramolecular hydrogen bonding, thus lowering intermolecular hydrogen bonding and also affecting packing of those molecules. Therefore it lowers the crystallinity of the compounds, resulting in lower melting points.
It is an object of the present invention to provide new compounds with pronounced physiological cooling effect without the disadvantage of strong odors and bitter taste.
It is also a further object of this invention to provide compounds with pronounced physiological cooling effect and relatively low melting points to provide the possibility of liquid coolants or coolant mixtures.
BRIEF DESCRIPTION OF THE INVENTION
We claim here that a series of compounds with the following structure having strong cooling effect, low melting point but no odor or taste.
The present invention provides a novel series of derivatives of 2,3-dimethyl-2-isopropylbutyric acid, with pronounced physiological cooling effect but no odor or taste. These compounds also possess relatively low melting points. These compounds are of the formula:
When n equals to 2, R is H or an aliphatic group attached to the oxygen atom; when n equals to 3, R is H or an aliphatic group.
The aliphatic group is intended to include any straight chain or branched alkyl group containing up to 6 carbon atoms. Typical such groups are methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, etc.
The incorporation of the oxygen atom into the chain of the amine “softens” the molecules, resulting in significantly lower melting points without affecting the taste quality of these compounds.
DETAILED DESCRIPTION OF THE INVENTION
Amides with this formula can be easily prepared by amidation reaction between alkoxyalkylamine (or hydroxyalkylamine) and 2,3-dimethyl-2-isopropylbutyryl chloride in the presence of a hydrogen chloride acceptor as shown in the following scheme. The hydrogen chloride acceptor can be a base, such as, sodium hydroxide, potassium hydroxide, etc, or a tertiary amine, such as, triethylamine, pyridine, etc. Such reactions are entirely conventional and can be understood by persons skilled in the art.
Preparations:
EXAMPLE 1 Preparation of N-(2-hydroxyethyl)-2,3-dimethyl-2-isopropylbutyramide (1)
A mixture of 19.5 g 2-aminoethanol and 50 mL anhydrous hexanes was cooled to 0° C. Under mechanical stirring 20 g freshly distilled 2,3-dimethyl-2-isopropylbutyryl chloride was added dropwise over a period of one hour while maintaining the reaction temperature below 5° C. The reaction mixture was then stirred for one more hour at this temperature followed by one hour at room temperature.
50 mL water was added and the top organic layer was separated and washed with water till is neutral. The solvent was evaporated and 21.5 g crude product (99+% GC purity) was obtained. The product was recrystallized from acetone/water.
EXAMPLE 2 Preparation of N-(3-hydroxypropyl)-2,3-dimethyl-2-isopropylbutyramide (4)
The procedure of Example 1 was repeated using 3-aminopropyl in place of 2-aminoethanol. N-(3-hydroxypropyl)-2,3-diemthyl-2-isopropylbutyramide (4, 99+% GC purity) was obtained as very viscous oil.
EXAMPLE 3 Preparation of N-(2-methoxyethyl)-2,3-dimethyl-2-isopropylbutyramide (2)
A mixture of 7.74 g 2-methoxyethylamine, 10.95 g triethylamine and 50 mL anhydrous hexanes was cooled to below 5° C. and under mechanical agitation 20 g freshly distilled 2,3-dimethyl-2-isopropylbutyryl chloride was added dropwise over a period of 30 minutes while maintaining the reaction temperature below 25 ° C. After addition the reaction mixture was stirred for 30 minutes at this temperature followed by one hour at room temperature.
50 mL water was added, the top organic layer was separated and washed with 20 mL 5% NaOH solution followed by water till it was neutral. The solvent was evaporated and 24.2 g crude product (2. 98.5+% GC purity) was obtained as viscous oil.
EXAMPLE 4 Preparation of N-(2-ethoxyethyl)-2,3-dimethyl-2-isopropylbutyramide (3)
The procedure of Example 3 was repeated using 2-ethoxyethylamine, in place of 2-methoxyethylamine. N-(2-ethoxyethyl)-2,3-dimethyl-2-isopropylbutyramide (3, 99+% GC purity) was obtained as viscous oil in quantitative yield.
EXAMPLE 5 Preparation of N-(3-methoxypropyl)-2,3-dimethyl-2-isopropylbutyramide (5)
The procedure of Example 3 was repeated using 3-methoxypropylamine in place of 2-methoxyethylamine. N-(3-methoxypropyl)-2,3-dimethyl-2-isopropylbutyramide (5, 99+% GC purity) was obtained in quantitative yield. The crude product was recrystallized with hexanes. m.p. 10° C.
EXAMPLE 6 Preparation of N-(3-ethoxypropyl)-2,3-dimethyl-2-isopropylbutyramide (6)
The procedure of Example 3 was repeated using 3-ethoxypropylamine in place of 2-methoxyethylamine. N-(3-ethoxypropyl)-2,3-dimethyl-2-isopropylbutyramide (6, 99+% GC purity) was obtained in almost quantitative yield. The crude product was recrystallized from acetone/water mixture. m.p. 30° C.
EXAMPLE 7 Preparation of N-(3-isopropoxypropyl)-2,3-dimethyl-2-isopropylbutyramide (7)
The procedure of Example 3 was repeated using 3-isopropoxypropylamine in place of 2-methoxyethylamine. N-(3-isopropoxypropyl)-2,3-dimethyl-2-isopropylbutyramide (7, 99+% GC purity) was obtained in almost quantitative yield. The product was further recrysallized from acetone/water mixture. m.p. 32° C.
EXAMPLE 6 Preparation of N-(3-butoxypropyl)-2,3-dimethyl-2-isopropylbutyramide (8)
The procedure of Example 3 was repeated using 3-butoxypropylamine in place of 2-methoxyethylamine. N-(3-butoxypropyl)-2,3-dimethyl-2-isopropylbutyramide (8, 99+% GC purity) was obtained in almost quantitative yield. The product was further purified by recrystallization from acetone/water mixture. m.p. 40° C.
Evaluation procedure:
The following testing procedure is aimed at determining physiological cooling ability of testing compounds with regard to WS-23 (N,2,3-Dimethyl-2-isopropylbutyramide). The tests are carried out on a selected panel of 5 people. The present test procedure is done on a statistical basis because sensitivity to cooling compounds will vary not only from compound to compound and from one part of the body to another, but from one individual to another as well. Tests of this nature are commonly used on the testing and quality control of the organoleptic properties, e.g. taste, smell of organic and inorganic food products.
1 g of each testing compound is dissolved in 99 g denatured ethanol to form 1% solution. 2 g such solution is then diluted with 8 g deionized water to form 2000 ppm solution. The solutions are then applied orally to determine the cooling effect.
To test the cooling activity of the compounds in this invention, the compounds prepared in this invention are tested repeatedly by the 5 selected panelists and the results are compared with WS-23.
These compounds all have a pronounced physiological cooling ability, and 1 mL 2000 ppm solution provides cooling sensation that lasts for 30 minutes. Several compounds exhibit equal or stronger cooling ability than WS-23.
The results are summarized in the table below.
Cooling
ability
compared
Entry
Compounds
m.p.
to WS-23
1
28° C.
−
2
−
3
+
4
−
5
10° C.
+
6
30° C.
+
7
32° C.
+
8
40° C.
+
+ means the compound has equal or stronger cooling effect than WS-23.
APPLICATIONS
The compounds in this invention give a physiological cooling effect on cold receptors of the skin and mucous membranes of the human body, especially those in the mouth, nose and throat. They can find a wide variety of applications in consumer products for consumption by or application to the human body. They can be added in candies and drinks to give cooling feeling. They can be incorporated toothpaste and other oral hygiene products to provide the long-lasting cooling, refreshing sensation. They can also be applied in medicines, such as in ointment and cough drops to provide soothing effect to relieve the burning on the skin and irritations to the throat.
Following are some examples utilizing compounds in this invention as physiological cooling agents. The applications of these compounds will not be limited to these examples.
Toothpicks:
Toothpick tips were soaked in 5% solution of Compound 3 in this invention in denatured ethanol for long enough to have enough deposition of the compound. The picks were then dried. When put on tongue, only pronounced cooling sensation exhibited with no detectable taste.
Mint candies:
Icing sugar was mixed with small amount of water at 50° C. to form a paste. 0.02% Compound 5 in this invention was added and stirred. Cooled to room temperature, the mixture hardened and was broken into smaller pieces. The candies had a marked cooling effect in the mouth.
Toothpaste:
Compound 6 in this invention
0.2%
Saccharine
0.2%
Flavor
0.8%
Potassium hydrophosphate (buffer)
40%
Carboxymethyl cellulose
1.0%
Synthetic sodium lauryl sulfate
2.0%
Gel
25.0%
Deionized water
to 100%
Toothpaste prepared this way gives refreshing sensation.
Mouthwash:
Menthol
1.0%
Compound 7 in this invention
0.5%
Sodium saccharine
0.3%
Denatured ethanol
40.0%
PEG hydrogenated castor oil
0.5%
Deionized water
to 100%
Using the mouthwash prepared according to this recipe gives clean, crispy breath without giving the bitter taste. | Novel compounds of 2,3-dimethyl-2-isopropylbutyric acid were claimed in this patent to possess pronounced cooling effect on the skin and on the mucous membranes of the body. These compounds also possess good taste quality and low melting points with no malodor. The preparations and some illustrative application of these compounds are also disclosed. | 2 |
BACKGROUND OF THE INVENTION
[0001] The invention relates to ventilation system for synchronous electrical machines, such as generators and motors. In particular, the invention relates to a stator mounted cooling fan for a forced gas stator ventilation system for generators having superconducting rotors.
[0002] In the process of producing electricity, power generators create heat that must be dissipated from the generator. Heat occurs in generators due primarily to windage and friction, electric current flow, and time-varying magnetic fields in magnetic structures. Frictional heating occurs as the rotor spins at high speed in the generator. Heating also occurs as current flows through the rotor and stator coils, as they rotate relative to one another in the magnetic fields of the generator. Losses in the magnetic circuit occur as the magnetic fields change with time in permeable materials, such as for example in the stator core and the rotor poles of a synchronous generator.
[0003] Generators are conventionally equipped with cooling systems, such as a gas ventilation system, to transfer heat from the stator and rotor away from the generator. Gas ventilation cooling systems have been used in conventional generators and motors that do not employ superconducting coils. These generators and motors have stators and rotors that require cooling. The conventional gas ventilation systems tightly couple the cooling of stator and rotor by providing cooling gas to both. The ventilation system cools the rotor and stator by forcing cooling gas through gas passages in the rotor and stator. Conventional ventilation systems have employed forward flow and reverse flows of cooling gases through the stator and rotor.
[0004] In a forward flow ventilation scheme the cooling gas flows through the rotor and stator. The rotor expels cooling gas into the air gap, where the expelled rotor flow mixes with “fresh” gas. The “fresh” gas flows from the fan and moves axially through the air gap along the length of the machine. The combination of the “fresh” gas and expelled rotor flow, flow into the stator cooling passages and serve to cool the stator. In a reverse flow ventilation scheme the rotor expels cooling gas into the air gap, where the expelled rotor flow mixes with gas which is expelled from the stator cooling passages. The combined flow then moves axially along the length of the machine and exits through the fan. Both forward flow and reverse flow ventilation schemes tend to couple the cooling of rotor and stator.
[0005] Because of the coupling of the cooling gas flows through the rotor and stator, conventional forward and reverse flow ventilation systems are configured to provide adequate cooling for both the stator and rotor. To cool the rotor, some compromises may have to be made in a conventional ventilation system with respect to cooling the stator in order to accommodate cooling needs of the rotor, and vice versa. It may be difficult to optimize the cooling of the stator or rotor with a ventilation system that must provide cooling for both the rotor and stator. Nevertheless, ventilation systems have conventionally provided cooling for both the stator and rotor in large industrial and utility power generators.
[0006] The cryogenic cooling system for a superconducting rotor does not cool the stator. The stator of such a superconducting synchronous machine requires a separate stator cooling system. Contrary to conventional machines where stator and rotor cooling systems are coupled in a single ventilation system, the cooling system of the cryogenic rotor and the gas-cooled stator may be separate and independent.
BRIEF SUMMARY OF THE INVENTION
[0007] A stator ventilation system has been developed for a superconducting synchronous machine. The stator of a superconducting synchronous machine is cooled by a forced ventilation system in which a cooling gas, such as air or hydrogen, is forced from or into stator cooling passages by a stator mounted fan. The stator mounted fan can be controlled to cool the stator to a uniform temperature over a range of ambient temperatures, machine loads and other operating conditions. In addition, a conventional synchronous machine and ventilation system may be retrofit with a stator mounted fan to enhance the cooling of the stator, even where the ventilation system cools both the stator and rotor.
[0008] In a first embodiment, the invention is a synchronous machine comprising: a rotor coupled to a rotor cooling system; a stator around the rotor and separated from the rotor by an annular gap between the rotor and an inner surface of the stator, wherein the stator includes stator cooling passages; a stator ventilation system in fluid communication with the stator cooling passages, wherein the ventilation system includes a cooling fluid driving device arranged adjacent an outer periphery of the stator.
[0009] In another embodiment the invention is a superconducting electromagnetic machine comprising: a rotor having a cryogenically cooled superconducting rotor coil winding; a stator coaxial with the rotor and having stator coils magnetically coupled with the superconducting rotor coil winding, and the stator having cooling passages extending from an outer periphery of the stator to an inner periphery of the stator, the rotor having cooling passages for a cryogenic cooling fluid; a stator ventilation system providing cooling gas to the outer periphery of the stator and passages of the stator, and the stator ventilation system further comprises at least one fan mounted around an outer periphery of the stator.
[0010] In a further embodiment the invention is a method for cooling an electromagnetic machine having a rotor including a rotor coil winding and a stator and a stator ventilation system, the method comprising: cooling the rotor coil winding; cooling the stator with a cooling gas flowing through the stator included in the stator ventilation system, and drawing the cooling gas through the stator by at least one fan included in the stator ventilation system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] [0011]FIG. 1 is a schematic cross-sectional diagram of a quarter-section of a generator showing a forced air, forward flow stator cooling system with stator mounted fans;
[0012] [0012]FIG. 2 is a graph showing generator output power verses ambient temperature for both a conventional turbine generator and a generator with stator mounted fans;
[0013] [0013]FIG. 3 is a graph of cooling gas flow through a generator verses ambient temperature for both a conventional generator and a generator with stator mounted fans;
[0014] [0014]FIG. 4 is a graph of generator cooling gas flow verses generator load for both a conventional generator and a generator with stator mounted fans;
[0015] [0015]FIG. 5 is a graph of generator efficiency verses generator load for a conventional generator and a generator with stator mounted fans;
[0016] [0016]FIG. 6 is a schematic cross-sectional diagram of a quarter-section of a generator showing a second embodiment of a forced air, forward flow cooling system with stator mounted fans;
[0017] [0017]FIG. 7 is a schematic cross-sectional diagram of a quarter section of a generator showing a third embodiment of a forced air, forward flow cooling system with stator mounted fans.
[0018] [0018]FIG. 8 is a schematic cross-sectional diagram of quarter section of a superconducting generator having an embodiment of a forced air, reverse flow cooling system.
[0019] [0019]FIG. 9 is a schematic cross-sectional diagram of a quarter section of a superconducting generator having a second embodiment of a forced air, reverse flow cooling system.
DETAILED DESCRIPTION OF THE INVENTION
[0020] In conventional generators with rotor mounted fans the cooling gas flow through the rotor is a function of speed. If such a generator that is rated at 60 Hz grid frequency (operation with a rotor speed of 3600 rpm for a 2-pole generator or 1800 rpm for a 4-pole generator) is operated at 50 Hz the rotor speed is reduced to 3000 rpm (2-pole) or 1500 rpm (4-pole) and the cooling gas flow is reduced roughly by the ratio 50/60. This reduces the heat removal capability of the generator, and hence the rating of the generator. It becomes difficult to accomplish identical generator output levels at both 50 and 60 Hz applications with a common generator design with conventional rotor mounted fans.
[0021] On the other hand, with stator mounted fans the coolant flow rate through the stator core, and hence the heat removal capability of the generator, is independent from the mechanical rotor speed. This allows to customize a generator design to 50 or 60 Hz operation through modifications to the external fan control module rather than changes in the electromagnetic design of the generator.
[0022] Since the air density is a function of elevation, the heat removal capability of air-cooled generators and hence the rating of air-cooled generators with rotor mounted fans is a function of elevation as well. As a result generators have to be de-rated if they are installed at higher elevation than they are designed for or rated at. A rough approximation is that the generator rating has to be reduced by up to 5% if the generator is operated at 1000 meter elevation compared to sea level. With a ventilation configuration of stator mounted fans the air flow through the generator can be increased to compensate for reduced air density and reduced heat removal capability as the elevation increases. This allows to maintain the generator rating independently of the elevation level of the generator installation.
[0023] [0023]FIG. 1 shows an exemplary synchronous electrical machine 10 having a stator 12 and a forward flow ventilation system 28 , in which cooling gas (arrows 30 ) flows from the rotor air gap 20 , and through the stator. The cooling gas flows through the radial gas passages 32 in the stator 12 . The cooling gas removes heat from the stator. Stator mounted fans 38 control the cooling gas flow rate and thereby regulate the stator temperature.
[0024] The machine 10 has a stator 12 and a rotor 14 . The machine 10 is shown as a generator, but it may also be an electric motor or other synchronous electrical machine. In a generator, the rotor includes field winding coil 16 that fits inside the cylindrical rotor cavity 18 of the stator. An annular machine air gap 20 is formed between the outside periphery of the rotor and the cylindrical surface of the stator that defines the cylindrical rotor cavity 18 which receives the rotor. As the rotor 14 turns within the stator, a magnetic field generated by the rotor and rotor coils rotates through the stator and creates an electrical current in the windings of the stator coils. This current is output by the generator as electrical power.
[0025] The rotor 14 has a generally longitudinally-extending axis 22 and a generally solid rotor core 24 . The solid rotor core has high magnetic permeability, and is usually made of a ferromagnetic material, such as iron. In a low power density superconducting machine, the iron core of the rotor is used to reduce the magnetomotive force (MMF), and, thus, minimize the amount of superconducting (SC) coil wire needed for the coil winding 16 .
[0026] The rotor 14 supports at least one longitudinally-extending, racetrack-shaped, high-temperature superconducting (HTS) coil winding 16 . The HTS coil winding may be alternatively a saddle-shape or have some other shape that is suitable for a particular HTS rotor design. The HTS coil winding 16 is cooled by cryogenic fluid or gas supplied to the rotor by an outside source 26 of cooling fluid. The cooling of the rotor and its HTS coils is independent of and isolated from cooling systems for other components of the generator 10 , such as the stator 12 .
[0027] In a superconducting synchronous machine, the rotor field winding is cooled to cryogenic temperatures by a cryorefrigeration system that includes its own self-contained rotor cooling circuit. A cold, cryogenic coolant is supplied to the rotor through a transfer coupling. The coolant flows through a cooling circuit in the rotor where it extracts heat from a superconducting rotor coil, and then returns to a stationary cooling system through the transfer coupling. The cryogenic cooling system provides effective cooling of the rotor in a superconducting machine. The cryogenic cooling system does not cool the stator.
[0028] From the outer periphery 34 of the stator core, the heated cooling gases 30 pass through annular ducts 36 that surround the stator core, and direct the hot gases to the stator mounted fans 38 . The fans 38 force cooling gas from the ducts 36 and draw the gas from the stator 12 . The stator mounted fans 38 control the flow of cooling gas through the stator and control stator cooling. The stator mounted fans have the capacity to draw a greater volume of cooling gas through the stator than was conventionally achieved with rotor mounted fans that forced air into or out of the stator-rotor gap 20 . The stator mounted fans are controlled by a fan controller 39 , such as by adjusting the fan speed to provide a desired cooling gas flow through the stator. The hot gases exhaust from the fans 38 into a plenum chamber 40 , and flow into a heat exchanger 42 . Gas flows through the fan into the annular plenum 40 , through the heat exchangers 42 , and into the return duct 44 at the front end of the generator.
[0029] The rate of cooling air or hydrogen flow through the stator passages is controlled by the stator fans, which are controlled by the fan controller. Fan controllers may be used for all embodiments of the ventilation systems disclosed herein. For example, the fan controllers may adjust the fan speed and hence cooling gas flow so as to maintain a uniform temperature of the stator windings. Temperature sensors 41 located at one or several locations in the stator core, the stator slots or the stator winding itself may provide a temperature feed back signal of the stator temperature to the fan controller which in turn adjusts the fan speed so as to increase or decrease the cooling gas flow through the stator depending on whether the stator temperature is above or below the desired stator temperature, respectively. For this purpose, different types of temperature sensors may be applied including sensors that measure temperatures at individual locations (point measurements) or sensors that provide information on the temperature distribution along a prescribed geometric path (distributed thermal sensors).
[0030] The stator mounted fans 38 may include two annular fan assemblies mounted around the stator to draw hot cooling gas from the annular ducts 36 surrounding the stator. These stator mounted fans may be controlled by the fan controller 39 to adjust the fan speed to provide the optimal cooling flow needed to maintain the stator at a desired relatively uniform operating temperature. In addition, another annular stator mounted fan 37 , may be positioned adjacent the stator end turns 48 so as to draw cooling gas 46 over the end turns. The stator mounted fans for the different sections of the stator may be controlled by a single fan controller, or may be individually controlled to provide various cooling flows through the different sections of the stator.
[0031] The size, design, and control of each stator fan may be optimized such that the fan is matched to the cooling flow resistance through the portion of the stator passages aligned with that fan. Similarly, the number and position of the fans on the stator frame may be selected to provide for substantially uniform temperature of the armature winding in the stator and the stator core along the axial length of the machine.
[0032] The control of the fans may be adjusted to achieve various benefits. For example, reducing the fan speed also reduces the audible windage noise from the machine. The fan speed can be reduced, for example, when the machine is operating at part load and less heat is being generated in the armature and stator core. Further, if number and size of the stator mounted fans is selected to exceed the stator cooling capacity of the machine at its rated load, then there will be additional stator cooling capacity available if the machine is operated beyond its rated load or the ambient temperature becomes excessive. Another potential benefit of the stator mounted fans is that they may be operated before the machine starts or after the machine stops so as to provide stator cooling even while the machine is at a standstill.
[0033] A rotor mounted fan 62 may or may not be used with a stator mounted fan to increase the gas flow through the air gap 20 between the rotor and stator. The speed of the rotor mounted fan is a function of rotor speed and, thus, increases the flow of cooling gas through the stator as the rotor speed increases. As most industrial gas turbines operate at a relatively steady rotor speed, the rotor fan provides a uniform force to the cooling gas flow through the ventilation system. The ventilation scheme may also be implemented without the rotor mounted fan 26 in which case all of the cooling gas is routed through the stator core without any rotor mounted fans, representing a major change in the state of the art of ventilation configurations of large utility type turbine generators.
[0034] The hot gases from the stator and fans are cooled in heat exchanger 42 , flow through recirculation ducts 44 and back into the machine air gap 20 . The cooling gases are driven into the gap 20 by centrifugal forces in the rotor, a rotor mounted fan 62 and by the gas flow through the stator drawn by the fans 33 . In addition, some of the cooling gases 46 are directed from the ventilation return passage 44 to cool the end turns 48 of the stator coil windings. Cooling gas not flowing past the end turns, flows into the machine air gap 20 and then enters the stator passages 32 at the stator inner periphery of the rotor cavity 18 .
[0035] [0035]FIG. 2 is a graph 50 showing the influence that ambient temperature (degrees Celcius) surrounding a power plant can have on the power output (megawatts—MW) of the equipment in the power plant. Turbine generators can be driven by two types of prime movers: steam turbines or combustion turbines such as gas turbines. The power output of a steam turbine does not vary with ambient temperature conditions whereas the output of the gas turbine is reduced as ambient temperature increase. The steam turbine characteristic is fairly flat, much like line 52 in FIG. 50. On the other hand, the output of a gas turbine is a strong function of ambient temperature, and generally has a characteristic with a negative slope, similar to the line 54 shown in FIG. 50. Since the mechanical power provided by the prime mover has to be converted by the generator to electric power, the output characteristic of the generator has to be coordinated with the turbine characteristic so that the output power of the power train is not limited by the generator capability. Since the two different types of prime movers have two different output characteristics (lines 52 vs 54 ) it becomes difficult to design one generator that can cost-effectively match both different turbine characteristics. This difficulty invariably leads to generators that are overdesigned over most parts of the ambient temperature range in order to meet the turbine output in the entire temperature range.
[0036] The power output of a generator with conventional ventilation configurations has a tendency to be reduced for higher ambient temperatures and follows a general trend line similar to line 54 . The negative slope is more pronounced in open ventilated air-cooled machines than in TEWAC designs where the generator heat is rejected through heat exchangers whose inlet cooling temperature is less of a function of ambient temperature.
[0037] In a ventilation configuration with stator mounted fans the cooling gas flow through the stator core can be controlled so that the generator output characteristic follows a desired curve. This allows to obtain a generator output characteristic that is decoupled from ambient temperatures. In particular, a constant output characteristic of line 52 , as well as a sloped characteristic of line 54 , can be accomplished, or any characteristic in between. With such a ventilation configuration it is substantially easier to coordinate the output characteristic of the generator with the two different prime movers of steam and gas turbines of same nominal ratings but different ambient following characteristics. FIG. 3 is a graph 56 showing that a stator mounted fan can increase the cooling gas flow (cubic feet per minute—cfm) through the stator as the ambient temperature increases. Increasing the cooling gas flow through the stator ventilation system as the ambient temperature increases cools the generator to reduce the effect that the ambient temperature has on generator power output, as shown by line 54 in FIG. 2. As shown by the positively sloped line 58 , the flow of cooling gas through the stator ventilation system can be controlled as a function of ambient temperature by controlling the stator mounted fans. A fan controller 39 (see FIG. 1) may be used to adjust the stator fan 38 speed(s) to achieve cooling gas flow shown by line 58 in FIG. 3. A conventional ventilation system, without a stator mounted fan or a fan controller, has a relatively constant flow of cooling gas through the stator a function of ambient temperature, as shown by line 60 .
[0038] [0038]FIG. 4 shows that a stator mounted fan can be used to increase the cooling gas flow through the stator ventilation system as the load on the generator increases, as is evident from sloped line 64 . A rotor mounted fan has a relatively constant speed when the generator is at normal operating speed, and thus the cooling as flow rate through the stator is constant, see line 66 , even while the load on the generator increases. A load increase generally increases the operating temperatures in the generator and such temperature changes can affect the power output and efficiency of the generator. See, e.g., FIG. 2. The speed of a stator mounted fan can be adjusted by the fan controller 39 to increase the cooling gas as the load on the generator increases and thereby improve the cooling of the stator by the ventilation system. The flow through the stator can also be adjusted to the generator load by switching selected fans on as load increases or off as load is reduced
[0039] [0039]FIG. 5 is a graph that shows a generator efficiency improvement due to a stator mounted fan. The stator mounted fan can compensate, at least in part, for changes in generator heat rejection due to changes in generator load and ambient temperature. The ventilation cooling system can more efficiently cool the stator, such as for example by maintaining the stator and generator at a more constant temperature. The ventilation system of a conventional turbine generator, line 68 , may be optimized for high load conditions. The cooling is less than optimal during low load conditions, e.g., below fifty percent (0.5) load capacity, because the stator is excessively cooled and operates at a lower than optimal temperature. Because of sub-optimal cooling, the efficiency of the generator may be unfavorably reduced at low loads due to the ventilation of the generator. A stator mounted fan, see line 70 , improves the efficiency of the generator by allowing the flow of cooling gas to be optimal over a wide-range of generator loads and ambient temperatures.
[0040] [0040]FIG. 6 shows a cross-section of one-quarter of a generator 10 (see rotor axial center-line 82 and longitudinal center-line 84 ) having a forward flow, ventilated stator cooling system 86 . The cooling system provides cooling gas 88 , e.g., ambient air or hydrogen, to the stator 12 and the cooling gas passages 32 in the stator. The stator cooling system 86 is independent of and isolated from the cryogenic cooling system that provides cryogen cooling fluid to the rotor.
[0041] Heat is extracted from the stator coils as the cooling gas passes through the stator cooling passages 32 . The passages may be arranged in the stator to optimize the cooling of the stator coils. For example, the frequency of cooling passages along the stator axis and/or the cross-sectional area of the passages may be selected to evenly distribute cooling in the stator or to otherwise optimize stator cooling.
[0042] The annular duct 36 may have an outer cylindrical wall 92 that circumferentially surrounds the stator and has openings and mounts for the stator mounted fans 38 . The duct 36 may also include annular baffle walls 94 extending from the stator to the cylindrical wall 92 to direct air from the stator passages 32 to the fans 38 . The baffle walls have apertures to allow cooling gas to flow to the stator fans, and are arranged to promote the relatively uniform flow of gas through all of the stator passages.
[0043] The annular plenum chamber duct 40 directs the hot high pressure or high velocity gas from fans 38 and directs the gas 88 to one or more heat exchangers 42 . The heat exchangers 42 extract heat from the gas so that it may be recirculated to cool the stator. In this embodiment, the cooled gas from the heat exchanger(s) flows directly across the end-turns 48 of the stator, in contrast to the ventilation system shown in FIG. 1. The cooling gas 90 flows from the end-turns and into the machine air gap 20 between the rotor and stator. As the gas flows through the air gap, it is distributed along the length of the rotor and enters the cooling passages 32 of the stator. The cooling gas may enter at just one end or at both ends of the rotor 82 . In this embodiment of the stator ventilation system 86 , the cooling gas is recirculated through the stator and a heat exchanger 42 removes heat from the cooling gas before it is recirculated through the stator.
[0044] [0044]FIG. 7 is a schematic cross-sectional diagram of a quarter section of a generator showing a third embodiment of a forced air, forward flow cooling system 96 with stator mounted fans. Whereas the second ventilation system embodiment 86 is a closed loop system in which cooling gas is recirculated (as shown in FIG. 6), the third embodiment 96 is an open looped system in which cooling gas flows through the stator 12 in a single pass and is then exhausted to ambient air. One of the benefits of an open loop cooling system is that a return duct (see 40 and 44 in FIG. 1) is not needed and thus the overall size of the machine may be reduced.
[0045] In the third embodiment 96 , cooling gas enters an inlet plenum 98 at one or both ends of the generator 80 . The cooling gas may be ambient air. Air flows from the inlet plenum over the end turns 48 of the stator windings, into the air gap 20 and stator passages 32 , through the stator fans 38 , and out through outlet plenums 100 . Heat exchangers are unnecessary because the heated cooling gas is exhausted to the atmosphere, and replaced by ambient air drawn in through the inlet plenum 98 . The fans may also be external to the stator frame and within the duct.
[0046] [0046]FIG. 8 is a schematic cross-sectional diagram of quarter section of a superconducting generator having an embodiment of a forced air, reverse flow cooling system 102 . In a reversed flow ventilation system cooling gas flows 104 into the stator passages at the outer periphery 34 of the stator, through the stator passages 32 and out into the air gap 20 between the rotor 14 and stator 12 . In a reverse flow ventilation system 102 , the flow through the stator passages 32 is opposite to the cooling gas flow in a forward flow ventilation system.
[0047] Heated cooling air flows from the air gap 20 and across the end-turns 48 of the stator winding. Stator mounted fans 106 draw the cooling gas across the end-turns, out of the air gap and from the stator passages. The stator mounted fans 106 control the flow through the stator passages and hence control the cooling of the stator. The stator mounted fans may be positioned around the end-turns 48 at the end(s) of the generator. Cooling gas flows from the stator mounted fans, into a plenum chamber 40 around the stator and through heat exchangers 108 and into ducts 36 before re-entering the stator passages. The heat exchangers remove heat from the cooling gas so that the gas may be recirculated through the stator passages.
[0048] [0048]FIG. 9 is a schematic cross-sectional diagram of quarter section of a superconducting generator having a second embodiment of a forced air or hydrogen, reverse flow cooling system 110 . In the second embodiment, cooling air 104 passes once through the ventilation system and is not recirculated. Air enters inlet plenums 112 arranged around the stator and flows into annular ducts 40 enclosing the stator. The air flows through stator passages 32 , the air gap 20 , and out of the air gap at the end(s) of the rotor. The heated cooling gas flows across the end-turns 48 of the stator winding so as to cool the end turns. The hot cooling gas is drawn from the stator, air gap and stator coil end turns by stator mounted fans 104 . The speed of the fans controls the rate of flow of the cooling gas and hence the cooling of the stator. Hot cooling gas from the stator fans exhaust through outlet plenums 114 mounted at the end(s) of the generator.
[0049] The stator cooling systems disclosed herein are also applicable for synchronous machines where a conventional rotor is replaced with a superconducting rotor. In such a case, the forward flow ventilation system of the original machine may be converted to a reverse flow system. A generator built with stator mounted fans can be uprated in the future by increasing either the number or the rating of stator mounted fans to increase the cooling gas flow through the stator core.
[0050] The stator ventilation systems with stator mounted fans presented here cover configurations where the stator winding is directly cooled. Direct stator cooling can be accomplished using hollow conductors in the armature winding in predominantly axial direction.
[0051] While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. | A synchronous electromagnetic machine is disclosed having: a rotor coupled to a rotor cooling system; a stator around the rotor and separated from the rotor by an annular gap between the rotor and an inner surface of the stator, wherein the stator includes stator cooling passages; a stator ventilation system in fluid communication with the stator cooling passages, and the ventilation system including a cooling fluid driving device such as a stator mounted fan. | 8 |
BACKGROUND OF THE INVENTION
Field of the Invention
The invention concerns a method for operating a computer tomography (also called computed tomography) system that includes an x-ray detector with a detector surface and with a detector middle, and a corresponding computer tomography system.
Description of the Prior Art
In some computer tomography systems, the x-ray detector is positioned in what is known as an asymmetrical partial fan arrangement relative to the x-ray source, as a result of which the center beam of the x-ray fan (which x-ray fan expands conically, emanating from the x-ray source) does not strike the middle of the x-ray detector, but rather strikes offset from the detector middle.
Computer tomography systems with an asymmetrical x-ray detector are also used, for example, as a type known as a T-detector in which detector elements are aligned along a line direction and are also aligned along a channel direction orthogonal to the line direction, wherein the number of detector elements that are aligned in the channel direction decreases as of a defined distance from the detector middle in the line direction.
In both types of computer tomography systems, the available value range for the pitch factor (which indicates the ratio of patient table feed to beam collimation in a type of scan known as a spiral scan, and whose value determines the image quality of the image data that can be generated and the beam exposure of the patient or subject to be examined) is disadvantageously limited.
SUMMARY OF THE INVENTION
On object of the invention is to provide an improved method to operate a computer tomography system, as well as an improved computer tomography system.
The method serves for operating a computer tomography system that includes an x-ray detector with a detector surface and with a detector middle, wherein sensor pixels for detection of x-ray radiation are arranged with non-uniform distribution over the detector surface. In at least one operating mode, either a pitch factor is selected and a value range for the extent of a reconstruction field for the image data preparation is determined depending on the distribution of the sensor pixels over the detector surface and depending on the selected pitch factor, or a value for the extent of the reconstruction field is selected and a value range for the pitch factor is determined depending on the distribution of the sensor pixels over the detector surface and depending on the selected value for the extent of the reconstruction field.
A significant advantage of this method is that, in many usage scenarios for the computer tomography system, a more advantageous and larger value range for the pitch factor can be and is provided to the operator for selection, and the corresponding value range is then adapted to the geometric design of the x-ray detector.
The pitch factor that describes the ratio of table feed of a patient bearing table of the computer tomography system to beam collimation affects the duration of an examination of a patient or of a subject, and affects the beam exposure of the patient or of the subject and the image quality of the image data that can be generated by the computer tomography system. As a result, different aspects are always to be considered in the selection of an advantageous pitch factor for every examination, and accordingly multiple values are to be provided to an operator for selection. An optimally advantageous and optimally large value range is accordingly advantageous. The upper limit of the value range is thereby of particular interest since the duration of an examination typically decreases with increasing value (thus for example given constant slice thickness). An optimally short examination duration is not only advantageous from an economic viewpoint, but also represents an increase in comfort for potential patients. Many patients perceive a corresponding examination by a computer tomography system to be uncomfortable, such that an optimally short examination duration is also desirable from the viewpoint of the patient.
In the following description, a sectional area that intersects the x-ray cone that emanates from the x-ray source of the computer tomography system at the level of the x-ray detector is designated as a detector surface. This sectional area can be covered with the sensor pixels for the sensory detection of the x-ray radiation emanating from the x-ray source. This detector surface is normally limited by the construction design of the computer tomography system. For example, given a computer tomography system with what is known as a gantry, the x-ray source and the x-ray detector are arranged opposing one another on the inner shell surface of a basic hollow cylinder shape, such that as a result the detector surface is also provided by a partial cylindrical shell surface. Its extent in the circumferential direction is limited by the aperture angle of the x-ray cone, and its extent in the middle longitudinal direction of the basic hollow cylinder shape is limited by the extent of the basic hollow cylinder shape (insofar as the x-ray detector projects beyond said basic hollow cylinder shape), by the extent of the x-ray detector or of a mount in this direction and the aperture angle of the x-ray cone.
The detector middle is furthermore to be understood as the position on the x-ray detector at which the middle beam of the beam cone that emanates from the x-ray source strikes at least in an initial bearing. An adjustment capability of the x-ray source and/or of the x-ray detector from an initial alignment is provided in operation, as a result of which a change of the alignment of the x-ray cone relative to the x-ray detector takes place. In this case, the detector middle is also to be understood as a fixed position on the surface of the x-ray detector.
From the extent of the reconstruction field, it is established how the sensors generated by means of the sensor pixels (according to a principle that is known per se) are prepared, and what extent the region of an examined patient or subject has that can ultimately be depicted graphically (thus in slice presentations) with the use of the acquired image data. For example, the extent of the reconstruction field thus determines whether slice presentations of the patient that reproduce the entire width of the patient are available after a spiral scan of the patient, or whether only slice presentations of a kidney of the patient are available.
The detector surface advantageously has a central region with a higher sensor pixel density, positioned around the detector middle, and a border region with a lower sensor pixel density that follows the central region. For example, this is also the case for x-ray detectors of the aforementioned type, such that the method is suitable for a very large range of application scenarios and is also applied in these cases.
In a preferred embodiment of the inventive method, a measurement field at the x-ray detector is associated with the reconstruction field such that the extent of the reconstruction field determines the extent of the measurement field, and wherein an (in particular uniform) base value range with a maximum value for the pitch factor is provided for all values of the extent of the measurement field that are smaller than or equal to the value of the extent of the central region. The measurement field corresponds to a projection of a region in an examination subject which should ultimately be graphically depicted onto the surface of the x-ray detector. The sensor signals of those sensor pixels that lie within the measurement field are then used in order to generate the image data for the graphical depiction. If—as is preferred—a higher sensor pixel density is now present in the central region, and if the extent of the measurement field is smaller than or equal to the extent of the central region, a particularly large value range for the pitch factor (for example of 0.4 to 1.5) is thus provided from which an operator can select.
Furthermore, it is advantageous for the upper limit of the value range for the pitch factor based on the maximum value to be smaller for values of the extent of the measurement field that are greater than the value of the extent of the central region. For the upper limit of the value range, a minimum value (of 0.75, for example) is preferably provided that is established as of a defined extent of the measurement field. The decreasing upper limit for the value range is then the fault of the lower sensor pixel density in the border region, and is specially adapted to this. Instead of thus simply providing a fixed value range with the minimum value as an upper limit, which upper limit is then valid independent of the size of the measurement value is provided accordingly, according to the method proposed here the value range is adapted to the extent of the measurement field so that a more advantageous and larger value range is used depending on the application case.
The adaptation or selection of a matching and advantageous value range for the pitch factor is hereby preferably performed by the operator within the scope of an examination planning in advance of every examination of a patient or subject, wherein at least two branches of a decision tree are provided to the operator as guidelines for selection via a control panel.
In one branch, via the control panel a value range for the pitch factor is provided to the operator, from which value range the operator selects a value via corresponding input. Depending on the selected value, an automatically adapted value range for the extent of the reconstruction field is then provided to the operator, from which the operator then in turn selects a value. The two decision layers do not necessarily need to follow one immediately after the other; additional decision layers in which additional values for additional parameters can be chosen can be present between them. The selection of the values for the additional parameters can then likewise affect the automatic specification of a value range for the extent of the reconstruction field.
In another branch, in contrast to this a value range for the extent of the reconstruction field is initially provided to the operator via the control panel, and after selection of a value from this value range by the operator a value range for the pitch factor is then determined automatically and provided to the operator, at least as a suggestion. In this case as well, additional decision layers can also be provided between these two decision layers, which additional decision layers can likewise affect the automatically provided or at least proposed value range for the pitch factor. The value ranges for the pitch factor and the extent of the reconstruction field are thus linked with one another, and via the two branches it is established which value range is adapted to which selection. A value range is preferably provided such that an operator can merely select values from this value range and make adjustments accordingly within the scope of the examination planning.
Alternatively, only one value range can be proposed and displayed to the operator, without limiting the selection of the actual adjustable values. Given a selection of a value outside of the automatically provided or proposed value range, at least one warning signal is then output (for example as an optical warning signal) via the control panel so that the operator can subsequently restart or correct the examination planning.
However, a method variant is preferable in which the selection of values for the operator is limited, and wherein an automatic adaptation (and in particular a reduction) of the value for the extent of the reconstruction field is conducted upon, for example, a selection by the operator of a value outside of the automatically proposed or provided value range for the pitch factor.
To increase the operating comfort, furthermore an operating mode for the computer tomography system is provided in which—based on a patient diameter that is determined by means of a topogram—a value for the extent of the reconstruction field and, adapted to this, a value range for the pitch factor are provided automatically via the control panel. If a whole-body scan or at least a scan over the entire width of a patient is thus provided, in this case a suitable value for the extent of the reconstruction field is determined automatically in which the image data of a topogram (thus an overview image scan) are evaluated fully automatically.
The above object also is achieved by a computer tomography system in accordance with the invention.
The computer tomography system according to the invention has a control panel and a control unit that is configured to execute the aforementioned method. The computer tomography system preferably has a T-detector with T-shaped sensor pixel distribution. This means that the sensor pixels cover a T-shaped area as viewed in the direction of the middle beam of the x-ray cone. For example, scintillators with downstream photodiodes, or what are known as direct transducers, for example, serve as sensor pixels. The individual sensor pixels are then typically combined into detector units, and multiple detector units form what are known as detector modules.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a computer tomography system with an x-ray detector.
FIG. 2 is a side view of the components of the computer tomography system of FIG. 1 .
FIG. 3 shows the x-ray detector of the computer tomography system in FIG. 1 in a plan view.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The exemplary embodiment described in the following and shown in FIG. 1 shows a computer tomography system 2 , an x-ray source 4 , an x-ray detector 6 , a patient support table (not shown in detail) and a control panel 8 with a control unit 10 integrated therein. The computer tomography system 2 serves for examination of patients or examination subjects 12 , wherein slice presentations of the examination subject 12 are generated according to a known manner by means of a spiral scan, for example.
With the x-ray source 4 , x-ray radiation is generated and emitted in the direction of the x-ray detector 6 , wherein an x-ray cone 14 (as indicated in FIG. 2 ) thereby forms, emanating from the x-ray source 4 . Corresponding to a simple geometric consideration, with the x-ray cone 14 a middle beam 16 is provided via which a detector middle 18 is established on the surface of the x-ray detector 6 .
The x-ray detector 6 has a base unit 20 into which the detector units 22 can be inserted. Via the constructive design of the base unit 20 that can be populated with detector units 22 , in the exemplary embodiment a detector surface 24 is established that is shaped in the manner of a partial cylindrical shell surface of a straight circular cylinder.
As shown in FIG. 3 , the detector surface 24 is not completely populated with detector units 22 , but rather a portion of the detector surface 24 is left open (unpopulated with detector units) at the edges so that—given a viewing direction in the middle beam direction 26 —the detector units 22 cover a T-shaped area. This design is sometimes also referred to as a T-detector. The x-ray detector 6 is thus completely populated in a line direction 28 , while the population in a channel direction 30 is incomplete in the line direction 28 as of a certain distance from the detector middle 18 . Due to this population, a central region 32 on the x-ray detector 6 is established in which a complete population is provided, as well as a border region 34 following this in the channel direction 30 and in the direction opposite this.
The detector units 22 are similar and are composed of sensor pixels, wherein scintillator crystals with downstream photodiodes and a corresponding readout matrix, or direct transducers, are used as sensor pixels, for example.
If the examination subject 12 should now be examined with a spiral scan, via the control panel 8 an operator starts an examination planning within the framework of which parameter adjustment for the computer tomography system 2 is selected by the operator via the control panel 8 , and the actual examination is subsequently started. The examination planning is designed in the manner of a decision tree, wherein the selection of a value for a parameter by the operator in many cases alters the selection of values for other parameters, for example in that the value range from which the operator can select is automatically reduced.
According to the inventive method, the two value ranges, respectively for the pitch factor and the extent of the reconstruction field R R are linked with one another in this way. The pitch factor—which describes the ratio of table feed of the patient bearing table to beam collimation—can typically also be indicated by the ratio of table feed per rotation of the x-ray detector 6 to the slice thickness of the slice presentations that are to be generated. Since the slice thickness can in most application cases be freely selected only within very narrow limits, ultimately a suitable selection of a value for the table feed often takes place given the selection of a suitable value for the pitch factor.
The extent of the reconstruction field R R describes the extent of the region of the patient or examination subject 12 that is depicted in the slice presentations generated by the spiral scan. Accordingly, the sensor signals of those sensor pixels that are situated within a measurement field on the surface of the x-ray detector 6 (which measurement field is imaged by projection of the region of the patient or of the examination subject 12 that is to be shown onto the surface of the x-ray detector 6 ) are of relevance to the preparation of the sensor signals of the sensor pixels to generate the slice presentations. This is shown in FIG. 2 . For the selection of adjustable values for the parameters that is offered to the operator within the scope of the examination planning, it is thereby significant whether and to what degree the extent of the measurement field R M is greater than the extent of the central region R ZB . It is assumed that the patient or the examination subject 12 is (as is typical) positioned centrally in the x-ray cone 14 for an examination, and thus is aligned with the middle beam 16 .
In many cases, the extent of the reconstruction field R R , and thus the extent of the measurement field R M that is dependent on this, are predetermined. For example, this is the case if the complete ribcage of a patient should be scanned. In this case, a topogram of the patient is then preferably acquired in advance of the examination planning for the actual examination, and a value for the extent of the measurement field R M (and thus also a value for the extent of the reconstruction field R R ) is determined by an evaluation unit on the basis of the image data of the topogram, which value for the extent of the measurement field R M is then automatically provided as a preset for the examination planning. If the operator then keeps this preselected value for the subsequent actual examination, as provided the generated slice presentations then image the entire rib cage of the patient. Moreover, the selection of values for the adjustment of the pitch factor is adapted to the preset value for the extent of the reconstruction field R R .
Insofar as the extent of the measurement field R M (which is dependent on the extent of the reconstruction field R RR [sic]) is smaller than the extent of the central region R ZB , a base value range of 0.4 to 1.5 for the pitch factor is provided to the operator. If the extent of the measurement field R M is greater than the extent of the central region R ZB , the value range for the pitch factor from which the operator can select is reduced with increasing extent of the measurement field R M such that the upper limit of the value range is increasingly reduced. As of a defined extent of the measurement field R M , however, the value range for the pitch factor remains constant, and the upper limit for the pitch factor lies at 0.75 for all extents of the measurement field R M that are greater than that defined value.
In contrast to this, in some cases a defined value or value range for the pitch factor is provided for a pending examination so that, within the scope of the examination planning, the operator initially adjusts a value for the pitch factor via the control panel 8 . In this case, an adaptation of the value range for the extent of the reconstruction field R R then takes place automatically, from which value range the operator can select and make adjustments for the subsequent examination.
Although modifications and changes may be suggested by those skilled in the art, it is the intention of the inventors to embody within the patent warranted heron all changes and modifications as reasonably and properly come within the scope of their contribution to the art. | In a computer tomography system having an x-ray detector with a detector surface at which sensor pixels, for detection of x-ray radiation, are distributed non-uniformly, and a method for operating such a system, either a pitch factor is selected, and a value range for an extent of a reconstruction field for image data is determined dependent on the distribution of the sensor pixels and dependent on the selected pitch factor, or a value for the extent of the reconstruction field is selected, and a value range for the pitch factor is determined dependent on the distribution of the sensor pixels and dependent on the selected value for the extent of the reconstruction field. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. provisional application Ser. No. 61/152,653, which was filed on Feb. 13, 2009. The entire contents of U.S. provisional application Ser. No. 61/152,653 are incorporated herein in their entirety.
TECHNICAL FIELD OF THE INVENTION
The present invention relates to processes for the preparation of compounds useful as inhibitors of p38 kinase. The processes of the present invention are amenable for large scale preparation and produce stable phenyl-6-(1-(phenyl)ureido)nicotinamides in high purity and yields.
BACKGROUND OF THE INVENTION
Protein kinases are involved in various cellular responses to extracellular signals. Recently, a family of mitogen-activated protein kinases (MAPK) has been discovered. Members of this family are Ser/Thr kinases that activate their substrates by phosphorylation [B. Stein et al., Ann. Rep. Med. Chem., 31, pp. 289-98 (1996)]. MAPKs are themselves activated by a variety of signals including growth factors, cytokines, UV radiation, and stress-inducing agents.
One particularly interesting MAPK is p38. p38, also known as cytokine suppressive anti-inflammatory drug binding protein (CSBP) and RK, was isolated from murine pre-B cells that were transfected with the lipopolysaccharide (LPS) receptor, CD14, and induced with LPS. p38 has since been isolated and sequenced, as has the cDNA encoding it in humans and mice. Activation of p38 has been observed in cells stimulated by stress, such as treatment of lipopolysaccharides (LPS), UV, anisomycin, or osmotic shock, and by cytokines, such as IL-1 and TNF.
Inhibition of p38 kinase leads to a blockade on the production of both IL-1 beta and TNF alpha. IL-1 and TNF stimulate the production of other proinflammatory cytokines such as IL-6 and IL-8 and have been implicated in acute and chronic inflammatory diseases and in post-menopausal osteoporosis [R. B. Kimble et al., Endocrinol., 136, pp. 3054-61 (1995)].
Based upon this finding, it is believed that p38, along with other MAPKs, have a role in mediating cellular response to inflammatory stimuli, such as leukocyte accumulation, macrophage/monocyte activation, tissue resorption, fever, acute phase responses and neutrophilia. In addition, MAPKs, such as p38, have been implicated in cancer, thrombin-induced platelet aggregation, immunodeficiency disorders, autoimmune disease, cell death, allergies, asthma, osteoporosis and neurodegenerative diseases. Inhibitors of p38 have also been implicated in the area of pain management through inhibition of prostaglandin endoperoxide synthase-2 induction. Other disease associated with IL-1, IL-6, IL-8 or TNF over-production are set forth in WO 96/21654.
2-(2,4-difluorophenyl)-6-(1-(2,6 difluorophenyl)ureido)nicotinamide (Compound I) having the structure depicted below, has demonstrated efficacy for the treatment of a variety of diseases, including acute and chronic inflammatory diseases. Compound I is described in WO 2004/72038, published on Aug. 26, 2004.
SUMMARY OF THE INVENTION
As described herein, the present invention provides processes for preparing p38 kinase inhibitors useful in the treatment of a number of diseases, including acute and chronic inflammatory diseases. Such compounds include 2-(2,4-difluorophenyl)-6-(1-(2,6 difluorophenyl)ureido)nicotinamide (Formula I) having the structure depicted below.
The processes of this invention have the advantage of allowing preparation of stable compounds of Formula 1 in high yield and purity, wherein R 1 , R 2 , R 3 , R 4 and R 5 are defined below. The present invention has the additional advantage of facile reaction conditions that are readily scaled up for large scale preparation. Additionally, the processes provides a more rapid production of the desired products relative to prior routes by reducing reaction times needed to complete individual transformations, and by eliminating the need for additional purification steps.
DETAILED DESCRIPTION OF THE INVENTION
Detailed Description of the Embodiments
In one aspect, this invention related to a process for preparing a compound of the Formula 4
comprising coupling a compound of Formula 2
with a compound of Formula 3
in the presence of a polar aprotic solvent.
Each R 1 , R 2 , R 4 and R 5 is independently selected from hydrogen, aliphatic, optionally substituted aryl, nitro, CN, OR′, CO 2 R′, CO 2 N(R′) 2 , NR′CO 2 R′, NR′C(O)NR′ 2 , OC(O)NR′ 2 , F, Cl, Br, I, OTs, OMs, OSO 2 R′, OC(O)R′. Each R′ is independently selected from hydrogen, C 1-6 aliphatic, or a 5-6 membered carbocyclic or heterocyclic ring system optionally substituted with 1 to 3 substituents independently selected from halo, C 1-6 alkoxy, cyano, nitro, amino, hydroxy, and C 1-6 aliphatic. Each R 3 is selected from hydrogen, C 1-6 aliphatic and aryl optionally substituted with C 1-6 aliphatic, aryl, nitro, CN, CO 2 R′, CO 2 N(R′) 2 , OR′, NCO 2 R′, NR′C(O)N(R′) 2 , or OC(O)N(R′) 2 . Each X is independently a leaving group. Each Z is independently selected from C 1-6 aliphatic, benzyl, Fmoc, or —SO 2 R′.
In one embodiment of this aspect, the solvent is dimethyl sulfoxide (DMSO), N-Methylpyrrolidone (NMP), CH 3 CN or dimethylformamide (DMF).
In another embodiment, the solvent is DMSO.
In one embodiment of this aspect, the coupling of a compound of Formula 2 with a compound of Formula 3 is performed in the presence of a base.
In one embodiment of this aspect, the base is a metal carbonate or a metal phosphate.
In certain embodiments, the base is a metal carbonate, such as cesium carbonate or potassium carbonate.
In some specific embodiments, the base is cesium carbonate.
In other embodiments, the base is a metal phosphate, such as potassium phosphate.
In one embodiment of this aspect, the coupling of a compound of Formula 2 with a compound of Formula 3 is performed at a temperature range of about 55-75° C. In other embodiments of this aspect, the coupling of a compound of Formula 2 with a compound of Formula 3 is performed at a temperature range of about 50-65° C. In still further embodiments of this aspect, the coupling of a compound of Formula 2 with a compound of Formula 3 is performed at a temperature range of about 55-60° C.
In another aspect, this invention provides a process for preparing a compound of the Formula 5
comprising performing a hydrolysis on a compound of Formula 4
using a protic acid, wherein
R 1 , R 2 , R 4 , R 5 , R′, R 3 and Z are defined above.
In one embodiment of this aspect, the hydrolysis of a compound of Formula 4 is performed in the presence of a solvent.
In one embodiment of this aspect, the solvent is water.
In one embodiment of this aspect, the protic acid is sulfuric acid, HCl or H 3 PO 4 .
In certain embodiments, the protic acid is sulfuric acid.
In one embodiment of this aspect, the final concentration of sulfuric acid is about 7M.
In one embodiment of this aspect, the hydrolysis of a compound of Formula 4 is performed at a temperature range of about 60-105° C.
In certain embodiments, the hydrolysis of a compound of Formula 4 is performed at a temperature range of about 95-105° C.
In specific aspects, the hydrolysis of a compound of Formula 4 is performed at a temperature of about 100° C.
In one embodiment of this aspect, the hydrolysis of a compound of Formula 4 is performed using a one-pot reaction.
In another aspect, this invention provides a process for preparing a compound of the Formula 5
comprising performing a hydrolysis on a compound of Formula 2
to provide a compound of Formula 12
and
coupling a compound of Formula 12 with a compound of Formula 11
wherein
R 1 , R 2 , R 4 , R 5 , R′, R 3 and X are defined above.
In some embodiments of this aspect, the coupling is performed in the presence of a solvent.
In some further embodiments, the solvent can be selected from MTBE, THF, DMSO, MeTHF, Toluene, pyridine, DMF, dichloromethane, diethyl ether and ethyl acetate.
In some embodiments of this aspect, the coupling is performed in the presence of a base.
In other embodiments the base used in the coupling step can be selected from LiHMDS, NaHMDS, KHMDS, KOtBu, and nBuLi.
In some embodiments the base used in the coupling step is KHMDS.
In some embodiments the coupling reaction is performed at a temperature in the range of about −20° C. and 25° C. (for example, −20° C. to −10° C., −10° C. to −8° C., −10° C. to 0° C. or 0° C. to 25° C.).
In another aspect, this invention provides a process for preparing a compound of Formula 1
comprising performing an amidation and a urea formation on a compound of Formula 5
by treating a compound of Formula 5 with:
i) a urea forming reagent; ii) an amidation reagent; and iii) anhydrous ammonia,
wherein
each R 1 , R 2 , R 4 and R 5 is independently selected from hydrogen, aliphatic, optionally substituted aryl, nitro, CN, OR′, CO 2 R′, CO 2 N(R′) 2 , NR′CO 2 R′, NR′C(O)NR′ 2 , OC(O)NR′ 2 , F, Cl, Br, I, OTs, OMs, OSO 2 R′, OC(O)R′; and
each R′ is independently selected from hydrogen, C 1-6 aliphatic, or a 5-6 membered carbocyclic or heterocyclic ring system optionally substituted with 1 to 3 substituents independently selected from halo, C 1-6 alkoxy, cyano, nitro, amino, hydroxy, and C 1-6 aliphatic.
In one embodiment of this aspect, the amidation reagent is phosgene, triphosgene or diphosgene.
In one embodiment of this aspect, the urea formation reagent is phosgene, triphosgene or diphosgene.
In one embodiment of this aspect, the amidation reagent and urea formation reagent are added at the same time.
In one embodiment of this aspect, the amidation reagent and urea formation reagent are the same.
In one embodiment of this aspect, the amidation and urea formation performed on a compound of Formula 5 are performed in the presence of a base.
In one embodiment of this aspect, the base is diisopropylethylamine, Huenigs base, or triethylamine.
In certain embodiments, the base is diisopropylethylamine.
In one embodiment of this aspect, the amidation and urea formation performed on a compound of Formula 5 are performed in the presence of a solvent.
In one embodiment of this aspect, the solvent is THF, MeTHF, or toluene.
In certain embodiments, the solvent is THF.
In one embodiment of this aspect, the compound of Formula 5 is treated with anhydrous ammonia after treatment with the amidation/urea formation reagent.
In one embodiment of this aspect, anhydrous ammonia is added to the product obtained after treatment of a compound of Formula 5 with the amidation/urea formation reagent, without isolation of said product.
In one embodiment of this aspect, the process further comprises isolating solid material after treating the solution with anhydrous ammonia, and washing the solid material with water followed by an acid wash to provide a compound of Formula 1.
In certain embodiments, the acid wash comprises a 1N H 2 SO 4 wash of the solid material.
In another aspect, this invention provides a process of providing a stable solid form of a compound of Formula 1, comprising slurrying a solid form of a compound of Formula 1
wherein
each R 1 , R 2 , R 4 and R 5 is independently selected from hydrogen, aliphatic, optionally substituted aryl, nitro, CN, OR′, CO 2 R′, CO 2 N(R′) 2 , NR′CO 2 R′, NR′C(O)NR′ 2 , OC(O)NR′ 2 , F, Cl, Br, I, OTs, OMs, OSO 2 R′, OC(O)R′; and each R′ is independently selected from hydrogen, C 1-6 aliphatic, or a 5-6 membered carbocyclic or heterocyclic ring system optionally substituted with 1 to 3 substituents independently selected from halo, C 1-6 alkoxy, cyano, nitro, amino, hydroxy, and C 1-6 aliphatic.
In one embodiment of this aspect, the compound of Formula 1 is stirred in a homogeneous or non-homogeneous solvent system.
In one embodiment of this aspect, the solvent system comprises methanol and water.
In one embodiment of this aspect, the methanol:water ratio in the solvent system is about 1:3.
In one embodiment of this aspect, the methanol:water ratio in the solvent system is about 1:1.
In one embodiment of this aspect, the compound is stirred for at least about 20 hours (e.g. about 24 hours).
In one embodiment of this aspect, the compound is stirred in a solvent system with a methanol:water ratio of about 1:3 for at least about 20 hours (e.g. about 24 hours), and then stirred in a solvent system with a methanol:water ratio of about 1:1 for at least about 20 hours (e.g. about 24 hours).
In one embodiment of this invention, each R 1 , R 2 , R 4 and R 5 is independently selected from hydrogen, F, Cl, Br, I, OTs or OMs.
In a further embodiment, each R 1 , R 2 , R 4 and R 5 is independently selected from hydrogen or F.
In one embodiment of this invention, each R 3 is independently selected from hydrogen or C 1-6 aliphatic.
In a further embodiment, each R 3 is independently selected from hydrogen or ethyl.
In one embodiment of this invention, each Z is independently C 1-6 aliphatic.
In a further embodiment, each Z is independently tert-butyl.
In another aspect, this invention provides a process for preparing Compound 10
comprising coupling Compound 11
with Compound 6
by dissolving Compounds 11 and 6 in Methyl tert-butylether (MTBE), treating the mixture with a base and stirring the mixture at a temperature of about −8° C. to −10° C. to obtain Compound 9
treating Compound 9 with triphosgene and diisopropylethylamine in the presence of tetrahydrofuran; stirring the solution until the reaction is complete; and treating the solution with anhydrous ammonia.
In one embodiment of this aspect, the base is LiHMDS, NaHMDS, KHMDS, KOtBu, or nBuLi.
In a further embodiment, the base is KHMDS.
In a further embodiment, the reaction temperature is between about −20° C. and 25° C. (for example, −20° C. to −10° C., −10° C. to −8° C., −10° C. to 0° C. or 0° C. to 25° C.).
In one embodiment of this aspect, the process further comprises isolating solid material after treating the solution with anhydrous ammonia, and washing the solid material with water followed by an acid wash to provide Compound 10.
In certain embodiments, the acid wash comprises a 1N H 2 SO 4 wash of the solid material.
In another embodiment, the reaction temperature is about 55° C. In a further aspect, this invention provides a process for preparing a compound of Formula 5
comprising performing a hydrolysis on a compound of Formula 7
using a protic acid, wherein
R 1 , R 2 , R 4 , R 5 , R′ and R 3 are defined above.
In one embodiment of this aspect, the hydrolysis of Compound 11 is performed in the presence of a solvent.
In one embodiment of this aspect, the solvent is water.
In one embodiment of this aspect, the protic acid is sulfuric acid.
In one embodiment of this aspect, the final concentration of sulfuric acid is about 7M.
In another aspect, this invention provides a process for preparing Compound 10
comprising coupling Compound 5
with Compound 7
by dissolving Compounds 5 and 7 in dimethyl sulfoxide, treating the mixture with cesium carbonate and stirring the mixture at a temperature of about 50-65° C. (e.g. 55-60° C.) to obtain Compound 8
treating Compound 8 with an aqueous solution of about 7M sulfuric acid and stirring the mixture at a temperature of about 95-105° C. (e.g. 100° C.) to obtain Compound 9
treating Compound 9 with triphosgene and diisopropylethylamine in the presence of tetrahydrofuran; stirring the solution until the reaction is complete; and treating the solution with anhydrous ammonia.
In one embodiment of this aspect, the process further comprises isolating solid material after treating the solution with anhydrous ammonia, and washing the solid material with water followed by an acid wash to provide Compound 10.
In certain embodiments, the acid wash comprises a 1N H 2 SO 4 wash of the solid material.
In some further embodiments, the process comprises stirring Compound 10 in solvent system comprising methanol and water, wherein the methanol:water ratio is about 1:3 for at least about 20 hours (e.g. about 24 hours); adding methanol to the mixture to change the solvent ratio to about 1:1 methanol:water; and continuing stirring for at least about 20 hours (e.g. about 24 hours).
In one aspect, this invention includes a Compound produced by the process of any of the above embodiments.
In one aspect, this invention provides a pharmaceutical composition produced by the process of any of the above embodiments.
DEFINITIONS AND GENERAL TERMINOLOGY
For purposes of this invention, the chemical elements are identified in accordance with the Periodic Table of the Elements, CAS version, Handbook of Chemistry and Physics, 75 th Ed. Additionally, general principles of organic chemistry are described in “Organic Chemistry”, Thomas Sorrell, University Science Books, Sausalito: 1999, and “March's Advanced Organic Chemistry”, 5 th Ed., Ed.: Smith, M. B. and March, J., John Wiley & Sons, New York: 2001, the entire contents of which are hereby incorporated by reference.
As described herein, Compounds of the invention may optionally be substituted with one or more substituents, such as are illustrated generally above, or as exemplified by particular classes, subclasses, and species of the invention. It will be appreciated that the phrase “optionally substituted” is used interchangeably with the phrase “substituted or unsubstituted.” In general, the term “substituted”, whether preceded by the term “optionally” or not, refers to the replacement of hydrogen radicals in a given structure with the radical of a specified substituent. Unless otherwise indicated, an optionally substituted group may have a substituent at each substitutable position of the group, and when more than one position in any given structure may be substituted with more than one substituent selected from a specified group, the substituent may be either the same or different at every position. Combinations of substituents envisioned by this invention are preferably those that result in the formation of stable or chemically feasible compounds. The term “stable”, as used herein, refers to compounds that are not substantially altered when subjected to conditions to allow for their production, detection, and preferably their recovery, purification, and use for one or more of the purposes disclosed herein. In some embodiments, a stable compound or chemically feasible compound is one that is not substantially altered when kept at a temperature of 40° C. or less, in the absence of moisture or other chemically reactive conditions, for at least a week.
The term “aliphatic” or “aliphatic group”, as used herein, means a straight-chain (i.e., unbranched) or branched, substituted or unsubstituted hydrocarbon chain that is completely saturated or that contains one or more units of unsaturation, or a monocyclic hydrocarbon or bicyclic hydrocarbon that is completely saturated or that contains one or more units of unsaturation, but which is not aromatic (also referred to herein as “carbocycle,” “cycloaliphatic” or “cycloalkyl”), that has a single point of attachment to the rest of the molecule. Unless otherwise specified, aliphatic groups contain 1-20 aliphatic carbon atoms. In some embodiments, aliphatic groups contain 1-10 aliphatic carbon atoms. In other embodiments, aliphatic groups contain 1-8 aliphatic carbon atoms. In still other embodiments, aliphatic groups contain 1-6 aliphatic carbon atoms, and in yet other embodiments aliphatic groups contain 1-4 aliphatic carbon atoms. In some embodiments, “cycloaliphatic” (or “carbocycle” or “cycloalkyl”) refers to a monocyclic C 3 -C 8 hydrocarbon or bicyclic or tricyclic C 8 -C 14 hydrocarbon that is completely saturated or that contains one or more units of unsaturation, but which is not aromatic, that has a single point of attachment to the rest of the molecule wherein any individual ring in said bicyclic ring system has 3-7 members. Suitable aliphatic groups include, but are not limited to, linear or branched, substituted or unsubstituted alkyl, alkenyl, alkynyl groups and hybrids thereof such as (cycloalkyl)alkyl, (cycloalkenyl)alkyl or (cycloalkyl)alkenyl. Suitable cycloaliphatic groups include cycloalkyl, bicyclic cycloalkyl (e.g., decalin), bridged bicycloalkyl such as norbornyl or [2.2.2]bicyclo-octyl, or bridged tricyclic such as adamantyl.
The term “heteroaliphatic”, as used herein, means aliphatic groups wherein one or two carbon atoms are independently replaced by one or more of oxygen, sulfur, nitrogen, phosphorus, or silicon. Heteroaliphatic groups may be substituted or unsubstituted, branched or unbranched, cyclic or acyclic, and include “heterocycle”, “heterocyclyl”, “heterocycloaliphatic”, or “heterocyclic” groups.
The term “heterocycle”, “heterocyclyl”, “heterocycloaliphatic”, or “heterocyclic” as used herein means non-aromatic, monocyclic, bicyclic, or tricyclic ring systems in which one or more ring members is an independently selected heteroatom. In some embodiments, the “heterocycle”, “heterocyclyl”, “heterocycloaliphatic”, or “heterocyclic” group has three to fourteen ring members in which one or more ring members is a heteroatom independently selected from oxygen, sulfur, nitrogen, or phosphorus, and each ring in the system contains 3 to 7 ring members.
The term “heteroatom” means one or more of oxygen, sulfur, nitrogen, phosphorus, or silicon (including, any oxidized form of nitrogen, sulfur, phosphorus, or silicon; the quaternized form of any basic nitrogen or; a substitutable nitrogen of a heterocyclic ring, for example N (as in 3,4-dihydro-2H-pyrrolyl), NH (as in pyrrolidinyl) or NR + (as in N-substituted pyrrolidinyl)).
The term “unsaturated”, as used herein, means that a moiety has one or more units of unsaturation.
The term “alkoxy”, or “thioalkyl”, as used herein, refers to an alkyl group, as previously defined, attached to the principal carbon chain through an oxygen (“alkoxy”) or sulfur (“thioalkyl”) atom.
The terms “haloaliphatic” and “haloalkoxy” means aliphatic or alkoxy, as the case may be, substituted with one or more halo atoms. The term “halogen” or “halo” means F, Cl, Br, or I. Examples of haloaliphatic include —CHF 2 , —CH 2 F, —CF 3 , —CF 2 —, or perhaloalkyl, such as, —CF 2 CF 3 .
The term “aryl” used alone or as part of a larger moiety as in “aralkyl”, “aralkoxy”, or “aryloxyalkyl”, refers to monocyclic, bicyclic, and tricyclic ring systems having a total of five to fourteen ring members, wherein at least one ring in the system is aromatic and wherein each ring in the system contains 3 to 7 ring members. The term “aryl” may be used interchangeably with the term “aryl ring”. The term “aryl” also refers to heteroaryl ring systems as defined herein below.
The term “heteroaryl”, used alone or as part of a larger moiety as in “heteroaralkyl” or “heteroarylalkoxy”, refers to monocyclic, bicyclic, and tricyclic ring systems having a total of five to fourteen ring members, wherein at least one ring in the system is aromatic, at least one ring in the system contains one or more heteroatoms, and wherein each ring in the system contains 3 to 7 ring members. The term “heteroaryl” may be used interchangeably with the term “heteroaryl ring” or the term “heteroaromatic”.
An aryl (including aralkyl, aralkoxy, aryloxyalkyl and the like) or heteroaryl (including heteroaralkyl and heteroarylalkoxy and the like) group may contain one or more substituents. Suitable substituents on the unsaturated carbon atom of an aryl or heteroaryl group are selected from halo; —R o ; —OR o ; —SR o ; 1,2-methylene-dioxy; 1,2-ethylenedioxy; phenyl (Ph) optionally substituted with R o ; —O(Ph) optionally substituted with R o ; —(CH 2 ) 1-2 (Ph), optionally substituted with R o ; —CH═CH(Ph), optionally substituted with R o ; —NO 2 ; —CN; —N(R o ) 2 ; —NR o C(O)R o ; —NR o C(O)N(R o ) 2 ; —NR o CO 2 R o ; —NR o NR o C(O)R o ; —NR o NR o C(O)N(R o ) 2 ; —NR o NR o CO 2 R o ; —C(O)C(O)R o ; —C(O)CH 2 C(O)R o ; —CO 2 R o ; —C(O)R o ; —C(O)N(R o ) 2 ; —OC(O)N(R o ) 2 ; —S(O) 2 R o ; —SO 2 N(R o ) 2 ; —S(O)R o ; —NR o SO 2 N(R o ) 2 ; —NR o SO 2 R o ; —C(═S)N(R o ) 2 ; —C(═NH)—N(R o ) 2 ; or —(CH 2 ) 0-2 NHC(O)R o wherein each independent occurrence of R o is selected from hydrogen, optionally substituted C 1-6 aliphatic, an unsubstituted 5-6 membered heteroaryl or heterocyclic ring, phenyl, —O(Ph), or —CH 2 (Ph), or, notwithstanding the definition above, two independent occurrences of R o , on the same substituent or different substituents, taken together with the atom(s) to which each R o group is bound, form a 3-8-membered cycloalkyl, heterocyclyl, aryl, or heteroaryl ring having 0-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur. Optional substituents on the aliphatic group of R o are selected from NH 2 , NH(C 1-4 aliphatic), N(C 1-4 aliphatic) 2 , halo, C 1-4 aliphatic, OH, O(C 1-4 aliphatic), NO 2 , CN, CO 2 H, CO 2 (C 1-4 aliphatic), O(haloC 1-4 aliphatic), or haloC 1-4 aliphatic, wherein each of the foregoing C 1-4 aliphatic groups of R o is unsubstituted.
An aliphatic or heteroaliphatic group, or a non-aromatic heterocyclic ring may contain one or more substituents. Suitable substituents on the saturated carbon of an aliphatic or heteroaliphatic group, or of a non-aromatic heterocyclic ring are selected from those listed above for the unsaturated carbon of an aryl or heteroaryl group and additionally include the following: ═O, ═S, ═NNHR*, ═NN(R*) 2 , ═NNHC(O)R*, ═NNHCO 2 (alkyl), ═NNHSO 2 (alkyl), or ═NR*, where each R* is independently selected from hydrogen or an optionally substituted C 1-6 aliphatic. Optional substituents on the aliphatic group of R* are selected from NH 2 , NH(C 1-4 aliphatic), N(C 1-4 aliphatic) 2 , halo, C 1-4 aliphatic, OH, O(C 1-4 aliphatic), NO 2 , CN, CO 2 H, CO 2 (C 1-4 aliphatic), O(halo C 1-4 aliphatic), or halo(C 1-4 aliphatic), wherein each of the foregoing C 1-4 aliphatic groups of R* is unsubstituted.
Optional substituents on the nitrogen of a non-aromatic heterocyclic ring are selected from —R + , —N(R + ) 2 , —C(O)R + , —CO 2 R + , —C(O)C(O)R + , —C(O)CH 2 C(O)R + , —SO 2 R + , —SO 2 N(R + ) 2 , —C(═S)N(R + ) 2 , —C(═NH)—N(R + ) 2 , or —NR + SO 2 R + ; wherein R + is hydrogen, an optionally substituted C 1-6 aliphatic, optionally substituted phenyl, optionally substituted —O(Ph), optionally substituted —CH 2 (Ph), optionally substituted —(CH 2 ) 1-2 (Ph); optionally substituted —CH═CH(Ph); or an unsubstituted 5-6 membered heteroaryl or heterocyclic ring having one to four heteroatoms independently selected from oxygen, nitrogen, or sulfur, or, notwithstanding the definition above, two independent occurrences of R + , on the same substituent or different substituents, taken together with the atom(s) to which each R + group is bound, form a 3-8-membered cycloalkyl, heterocyclyl, aryl, or heteroaryl ring having 0-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur. Optional substituents on the aliphatic group or the phenyl ring of R + are selected from NH 2 , NH(C 1-4 aliphatic), N(C 1-4 aliphatic) 2 , halo, C 1-4 aliphatic, OH, O(C 1-4 aliphatic), NO 2 , CN, CO 2 H, CO 2 (C 1-4 aliphatic), O(halo C 1-4 aliphatic), or halo(C 1-4 aliphatic), wherein each of the foregoing C 1-4 aliphatic groups of R + is unsubstituted.
The term “alkylidene chain” refers to a straight or branched carbon chain that may be fully saturated or have one or more units of unsaturation and has two points of attachment to the rest of the molecule. The term “spirocycloalkylidene” refers to a carbocyclic ring that may be fully saturated or have one or more units of unsaturation and has two points of attachment from the same ring carbon atom to the rest of the molecule.
The term “stable,” as used herein, refers to compounds that are not substantially altered when subjected to conditions to allow for their production, detection, and preferably their recovery, purification, and use for one or more of the purposes disclosed herein, such as administration to a mammal by methods known in the art. In some embodiments, a stable compound or chemically feasible compound is one that is not substantially altered when kept at a temperature of 40° C. or less, in the absence of moisture or other chemically reactive conditions, for at least a week.
The term “leaving group,” as used herein, has the definition described by “March's Advanced Organic Chemistry”, 5 th Ed., Ed.: Smith, M. B. and March, J., John Wiley & Sons, New York: 2001.
The term “amidation,” as used herein, is defined as a process of producing an amide moiety. An example of a process of this type is, without limitation, the coupling of ammonia or an amine functionality with a compound bearing a carbonyl which itself bears a leaving group. A pictorial representation of a non-limiting, general example of the process of amidation, wherein X is a leaving group and R o is defined as above, is:
The term “urea” as used herein, is defined as any compound which contains in its structure a carbonyl bearing two amine functionalities. A pictorial representation of a non-limiting, general example of a urea, wherein R o is defined as above, is:
The term “urea forming reagent,” as used herein, is defined as a carbonyl containing compound, wherein a carbonyl moiety bears two leaving groups, and can take part in the process of urea formation as defined below.
The term “urea formation,” as used herein, is defined as a process of producing a urea moiety. An example of a process of this type is, without limitation, the coupling of ammonia or an amine functionality with a urea forming reagent. A pictorial representation of a non-limiting, general example of the process of urea formation, wherein X 1 and X 2 are leaving groups and R o is defined as above, is:
The term “one-pot reaction,” as used herein, is defined as a process, wherein two or more distinct chemical transformations of a substrate occur upon the stepwise or simultaneous addition of one or more chemical reagents, without separation or purification of intermediate compounds.
The term “slurry,” as used herein, is defined as a mixture comprising a solid and a liquid, wherein the solid is, at most, partially soluble in the liquid. The term “slurrying” or “slurried,” as used herein (example, “the solid product was slurried for 24 hours”), is defined as the act of creating a slurry, and stirring said slurry for a length of time.
The term “protecting group,” as used herein, represents those groups intended to protect a functional group, such as, for example, an alcohol, amine, carboxyl, carbonyl, etc., against undesirable reactions during synthetic procedures. Commonly used protecting groups are disclosed in Greene and Wuts, Protective Groups in Organic Synthesis, 3 rd Edition (John Wiley & Sons, New York, 1999), which is incorporated herein by reference. Examples of nitrogen protecting groups include acyl, aroyl, or carbamyl groups such as formyl, acetyl, propionyl, pivaloyl, t-butylacetyl, 2-chloroacetyl, 2-bromoacetyl, trifluoroacetyl, trichloroacetyl, phthalyl, o-nitrophenoxyacetyl, α-chlorobutyryl, benzoyl, 4-chlorobenzoyl, 4-bromobenzoyl, 4-nitrobenzoyl and chiral auxiliaries such as protected or unprotected D, L or D, L-amino acids such as alanine, leucine, phenylalanine and the like; sulfonyl groups such as benzenesulfonyl, p-toluenesulfonyl and the like; carbamate groups such as benzyloxycarbonyl, p-chlorobenzyloxycarbonyl, p-methoxybenzyloxycarbonyl, p-nitrobenzyloxycarbonyl, 2-nitrobenzyloxycarbonyl, p-bromobenzyloxycarbonyl, 3,4-dimethoxybenzyloxycarbonyl, 3,5-dimethoxybenzyloxycarbonyl, 2,4-dimethoxybenzyloxycarbonyl, 4-methoxybenzyloxycarbonyl, 2-nitro-4,5-dimethoxybenzyloxycarbonyl, 3,4,5-trimethoxybenzyloxycarbonyl, 1-(p-biphenyl)-1)-1-methylethoxycarbonyl, α,α-dimethyl-3,5-dimethoxybenzyloxycarbonyl, benzhydryloxycarbonyl, t-butyloxycarbonyl, diisopropylmethoxycarbonyl, isopropyloxycarbonyl, ethoxycarbonyl, methoxycarbonyl, allyloxycarbonyl, 2,2,2,-trichloroethoxycarbonyl, phenoxycarbonyl, 4-nitrophenoxy carbonyl, fluorenyl-9-methoxycarbonyl, cyclopentyloxycarbonyl, adamantyloxycarbonyl, cyclohexyloxycarbonyl, phenylthiocarbonyl and the like, arylalkyl groups such as benzyl, triphenylmethyl, benzyloxymethyl and the like and silyl groups such as trimethylsilyl and the like. Preferred N-protecting groups are tert-butyloxycarbonyl (Boc).
Examples of useful protecting groups for acids are substituted alkyl esters such as 9-fluorenylmethyl, methoxymethyl, methylthiomethyl, tetrahydropyranyl, tetrahydrofuranyl, methoxyethoxymethyl, 2-(trimethylsilyl)ethoxymethyl, benzyloxymethyl, pivaloyloxymethyl, phenylacetoxymethyl, triisopropropylsysilylmethyl, cyanomethyl, acetol, phenacyl, substituted phenacyl esters, 2,2,2-trichloroethyl, 2-haloethyl, ω-chloroalkyl, 2-(trimethylsilyl)ethyl, 2-methylthioethyl, t-butyl, 3-methyl-3-pentyl, dicyclopropylmethyl, cyclopentyl, cyclohexyl, allyl, methallyl, cynnamyl, phenyl, silyl esters, benzyl and substituted benzyl esters, 2,6-dialkylphenyl esters such as pentafluorophenyl, 2,6-dialkylpyhenyl. Preferred protecting groups for acids are methyl or ethyl esters.
Methods of adding (a process generally referred to as “protection”) and removing (process generally referred to as “deprotection”) such amine and acid protecting groups are well-known in the art and available, for example in P. J. Kocienski, Protecting Groups, Thieme, 1994, which is hereby incorporated by reference in its entirety and in Greene and Wuts, Protective Groups in Organic Synthesis, 3 rd Edition (John Wiley & Sons, New York, 1999).
Unless otherwise stated, structures depicted herein are also meant to include all isomeric (e.g., enantiomeric, diastereomeric, and geometric (or conformational)) forms of the structure; for example, the R and S configurations for each asymmetric center, (Z) and (E) double bond isomers, and (Z) and (E) conformational isomers. Therefore, single stereochemical isomers as well as enantiomeric, diastereomeric, and geometric (or conformational) mixtures of the present compounds are within the scope of the invention. Unless otherwise stated, all tautomeric forms of the compounds of the invention are within the scope of the invention. Additionally, unless otherwise stated, structures depicted herein are also meant to include compounds that differ only in the presence of one or more isotopically enriched atoms. For example, compounds having the present structures except for the replacement of hydrogen by deuterium or tritium, or the replacement of a carbon by a 13 C- or 14 C-enriched carbon are within the scope of this invention. Such compounds are useful, for example, as analytical tools, probes in biological assays, or p. 38 inhibitors with improved therapeutic profile.
Processes and Intermediates
As used herein, abbreviations, symbols and conventions are consistent with those used in the contemporary scientific literature. See, e.g., Janet S. Dodd, ed., The ACS Style Guide: A Manual for Authors and Editors, 2nd Ed., Washington, D.C.: American Chemical Society, 1997, herein incorporated in its entirety by reference.
Compounds of Formula 1 can be synthesized according to Scheme 1.
Compounds of Formula 8 can be prepared by coupling a compound of Formula 6, wherein X is a leaving group, with a boronic acid compound of Formula 7 in a suitable organic solvent (e.g. EtOH), in the presence of a suitable transition metal catalyst (e.g. Palladium tetrakis(triphenylphosphine)), in the presence of a suitable base (e.g. an alkali metal base such as Na 2 CO 3 ) at temperatures between 70° C. and 90° C. Compounds of Formula 6 and 7 can be purchased commercially or synthesized using methods known to those skilled in the art.
An N-oxide compound of Formula 9 can be prepared from a compound of Formula 8 by oxidation with a suitable oxidizing agent (e.g. mCPBA) in a suitable solvent (e.g. CH 2 Cl 2 ) at a suitable temperature (e.g. 20-40° C.).
A compound of Formula 2 can be synthesized by treatment of a compound of Formula 9 with a suitable agent such as a chlorinating agent (e.g. POCl 3 ), in a suitable solvent (e.g. 1,2-dichloroethane).
Compounds of Formula 4 can be synthesized by coupling a compound of Formula 2 with a compound of Formula 3 in the presence of a suitable alkali metal salt (e.g. cesium carbonate) and a suitable polar organic solvent (e.g. DMSO). Subsequently, the reaction mixture is treated with a suitable diluted aqueous acid (e.g. 1N HCl) and the product recrystallized from a suitable polar solvent (e.g. EtOH). Alternatively, compounds of Formula 4 can be prepared by coupling a compound of Formula 2 with a compound of Formula 3 in the presence of a transition metal catalyst (e.g. Pd(OAc) 2 ) as generally described in PCT application WO 2004/072038 and U.S. Pat. No. 7,115,746, the disclosures of which are hereby incorporated herein by reference in their entirety. Phenyl carbamates of Formula 4 can be purchased commercially or synthesized from the corresponding anilines using methods known to those skilled in the art.
Compounds of Formula 5 can be prepared from compounds of Formula 4 using a one-pot procedure wherein a compound of Formula 4 is treated with an acid in such a way to promote hydrolysis of the carbamate and ester functionalities. Alternatively, a compound of Formula 5 can be prepared from a compound of Formula 4 by first hydrolyzing the carbamate group followed by the hydrolysis of the ester to the corresponding carboxylic acid.
Compounds of Formula 1 can be prepared from compounds of Formula 5 by reacting a compound of Formula 5 with triphosgene or suitable equivalent reagent, followed by treatment with anhydrous ammonia.
Compounds of Formula 1 can also be recrystallized to a more stable form by treating a compound of Formula 1 with a mixture of water and a polar protic organic solvent.
EXAMPLES
The following preparative examples are set forth in order that this invention be more fully understood. These examples are for the purpose of illustration only and are not to be construed as limiting the scope of the invention in any way.
Example 1
Preparation of ethyl 6-chloro-2-(2,4-difluorophenyl)nicotinate (5)
Preparation of ethyl 2-(2,4-difluorophenyl)nicotinate (3)
To a nitrogen purged 3.0 L, 4-necked flask, fitted with an overhead stirrer, thermocouple, heating mantle, nitrogen outlet and reflux condenser, was charged Pd(Ph 3 ) 4 (5.0 g, 4.33 mmoles, 0.005 eq), sodium carbonate (92.6 g, 874 mmoles, 1.3 eq), ethyl 2-chloronicotinate, 1 (126.0 g, 678 moles, 1.0 eq), 2,4-difluorophenylboronic acid, 2 (125 g, 791 mmoles, 1.2 eq), followed by 0.5 L of toluene and 125 mL denatured EtOH. The reaction was heated to 82° C. with vigorous stirring under N 2 overnight (completeness of reaction determined by HPLC and TLC). The reaction was cooled to room temperature, the mixture filtered through a small pad of Celite® and the solvents removed under vacuum at 55° C. The residue was dissolved in EtOAc, washed, dried (MgSO 4 ), filtered through Celite® again, and concentrated. The product was obtained as a yellow solid.
Preparation of 2-(2,4-difluorophenyl)-3-(ethoxycarbonyl)pyridine 1-oxide (4)
To a nitrogen purged, 12 L, 5-necked flask, fitted with an overhead stirrer, a thermocouple and a condenser, was charged ethyl 2-(2,4-difluorophenyl)nicotinate, 3 (144 g, 548 mmoles, 1.0 eq), and 4 L of CH 2 Cl 2 . With stirring, mCPBA was added over 5 minutes, and the temperature was gradually increased from 22 to 38° C. in 45 minutes (completeness of reaction determined by HPLC). The reaction was cooled to room temperature and the contents slowly poured into 3 L of water. Na 2 SO 3 was added slowly (exotherm from 20 to 33° C.) until the peroxide test (starch/I 2 paper) indicated no peroxides remained in the mixture. The aqueous layer was separated and the organic layer was washed with saturated NaHCO 3 (˜3 L). The organic layer was dried with MgSO 4 , filtered, and concentrated to a brown thick oil. The oil was then treated with MTBE (2 L) and stirred to give a white precipitate, which was collected by filtration, washed with MTBE and dried under vacuum to give the title Compound 4.
Preparation of ethyl 6-chloro-2-(2,4-difluorophenyl)nicotinate (5)
To a nitrogen purged 500 mL, 3-necked flask, fitted with a reflux condenser, heating mantle and a thermocouple was charged 2-(2,4-difluorophenyl)-3-(ethoxycarbonyl)pyridine 1-oxide, 4 (21 g, 75 mmoles, 1.0 eq), followed by 150 mL dichloroethane. Phosphorous oxychloride (75 mL) was added in one aliquate with stirring, causing an immediate rise in temperature from 21 to 23° C. followed by gradual warming. The solution was heated under nitrogen to 70-75° C. (completeness of reaction determined by HPLC). The reaction was then cooled to room temperature and concentrated under vacuum to remove most of the POCl 3 . The remainder was quenched by slowly pouring onto 450 g of ice. The mixture (after the ice melted) was then extracted into methylene chloride (2×200 mL). The combined organics were dried (MgSO 4 ), filtered through silica, eluted with methylene chloride, and concentrated to give the title Compound, 5, as an orange solid. 1 H NMR (500.0 MHz, CDCl 3 ) d 8.15 (d, J=8.2 Hz, 1H), 7.54 (td, J=8.5, 5.0 Hz, 1H), 7.34 (d, J=8.2 Hz, 1H), 6.96-6.92 (m, 1H), 6.79-6.74 (m, 1H), 4.16 (q, J=7.2 Hz, 2H), 1.10 (t, J=7.1 Hz, H) ppm.
Example 2
Preparation of tert-butyl 2,6-difluorophenylcarbamate (7)
2,6-Difluoroaniline, 6 (4.5 mL, 42 mmol, 1.0 equiv.), and Boc anhydride (11.1 g, 51 mmol, 1.2 equiv.) were mixed in THF and to this mixture was added 1M sodium hexamethyldisilazide (100 mL, 100 mmol, 2.3 equiv.) at room temperature (completeness of reaction determined by HPLC). 50 mL brine was then added, and the solution was concentrated and extracted with EtOAc (2×100 mL). The combined organics were washed with brine (1×50 mL), followed by citric acid (2×10%). The resulting solution was then dried over MgSO 4 , filtered and concentrated to give the title Compound, 7, as an orange solid which was used directly in the next step without additional purification. 1 H NMR (500.0 MHz, CDCl 3 ) 7.18-7.13 (m, 1H), 6.96-6.91 (m, 2H), 6.06 (s, 1H) and 1.52 (s, 9H) ppm
Example 3
Preparation of ethyl 6-(tert-butoxycarbonyl(2,6-difluorophenyl)amino)-2-(2,4-difluorophenyl)nicotinate (8)
A mixture of Compound 5 (100.82 g, 0.33 mol, 1.0 equiv.), Compound 7 (101.05 g, 0.44 mol, 1.30 eq), and cesium carbonate (177.12 g, 0.54 mol, 1.60 eq) was suspended in DMSO (250 mL, 2.5 volumes) and stirred vigorously at 55-60° C. for 48 hours (completeness of reaction determined by HPLC). The mixture was cooled to 20-30° C. and the base was quenched by careful and slow addition of a 1 N HCl (aq) solution (540 mL, 1.60 eq), keeping the internal temperature of the reaction mixture below 30° C. Upon cooling, a precipitate formed and was filtered and washed with water (2×250 mL, 2×2.5 volumes). The precipitate was then suspended in absolute ethanol (1000 mL, 10 volumes) and heated to reflux. The reflux was maintained for 30-60 minutes, and water (200 mL, 2 volumes) was added to the mixture. The resulting mixture was then heated again to reflux, and reflux was maintained for 30 minutes, at which point the suspension was cooled to 10° C. The resulting solids were then filtered and washed with water (2×250 mL, 2×2.5 volumes), followed by absolute ethanol (250 mL, 2.5 volumes), and then transferred to a vacuum oven and dried at 50-60° C. The title Compound, 8, was obtained as a white crystalline solid. ( 1 H NMR, 500 MHz; CDCl 3 ) δ 8.28 (d, 1H), 8.12 (d, 1H), 7.19 (q, 1H), 6.96 (t, 2H), 6.81 (t, 1H), 6.74 (t, 1H), 4.25 (q, 2H), 1.50 (s, 9H), 1.20 (t, 3H).
Example 4
Preparation of 2-(2,4-difluorophenyl)-6-(2,6-difluorophenylamino)nicotinic acid (9)
To Compound 8 (100 g, 0.204 mol, 1.00 eq) was added a 7M sulfuric acid solution prepared by the slow addition of concentrated sulfuric acid (285 mL, 2.85 vol, 5.24 mol) to distilled water (465 mL, 4.65 vol) while keeping the temperature below 50° C. The mixture was heated at 100±5° C. until the reaction was complete. The mixture was then cooled to 30±5° C. and additional water (750 mL, 7.5 vol) was added. Isopropyl acetate (2 L, 20 vol) was then added and the mixture was stirred for 15 minutes. Stirring was stopped and the phases were allowed to separate. The aqueous phase was separated and water (7.5 vol) was charged to the organic phase. The mixture was stirred for 15 minutes, polish filtered, then the aqueous phase was drained. The total volume of the organic layer was reduced to 4 vol by vacuum distillation at 45±5° C. The resulting slurry was cooled to −10° C. for 12 hours and filtered. The filter and cake was washed with cold isopropyl acetate (3 vol) and the solids were dried under vacuum at 50±5° C. to give the title Compound, 9, as a white solid. ( 1 H NMR, 500 MHz; DMSO-d 6 ) δ 12.50 (s, 1H), 9.25 (s, 1H), 8.07 (d, 1H), 7.39 (q, 1H), 7.29 (m, 1H), 7.18 (m, 3H), 7.09 (m, 1H), 6.25 (m, 1H).
Example 5
Preparation of 2-(2,4-difluorophenyl)-6-(1-(2,6-difluorophenyl)ureido)nicotinamide (10)
Triphosgene (38.87 g, 0.1276 mol, 0.9 eq) and Compound 9 (51.14 g, 0.1412 mo, 1 eq.) were charged to a reactor. Anhydrous THF (486 mL, 9.5 vol) was then added and the clear solution was cooled to −30±5° C. Diisopropylethylamine (73.79 mL, 0.424 mol, 3.0 eq) in THF (103 mL, 2.5 vol) was charged to the reactor keeping the temperature below −20° C. After addition, the reaction mixture was warmed to 20±3° C. The mixture was stirred for 2 hours and was then filtered through Celite®, and the cake was rinsed with THF (767 mL, 15 vol). The filtrate was cooled to −30° C. and anhydrous NH 3 (3 equiv.) added. The resulting white slurry was purged with N 2 and warmed up to 20±3° C. for 1 hour. The reaction mixture was then cooled to 0±5° C. for 30 minutes. The mixture was again filtered and the reactor was rinsed with THF (255 mL, 5 vol). The cake was rinsed with H 2 O (255 mL, 5.0 vol) followed by 1N H 2 SO 4 (10 vol). The solid was then transferred to a vacuum oven and dried at 35±3° C. to give the title Compound, 10, as a white solid. ( 1 H NMR, 500 MHz; DMSO-d 6 ) δ 7.97 (d, 1H), 7.85 (s, 1H), 7.56 (quin, 1H), 7.45 (q, 1H), 7.40 (s, 2H), 7.28 (t, 3H), 7.15 (td, 1H), 7.06 (d, 1H).
Example 6
Preparation of a solid form of 2-(2,4-difluorophenyl)-6-(1-(2,6-difluorophenyl)ureido)nicotinamide (10)
A slurry of Compound 10 (407.74 mL, 1.01 mol, 1.00 eq) in methanol (6.52 L, 16.0 vol) was heated to 60° C. until a solution was obtained. The reactor contents were then cooled to 48° C., held at this temperature until crystallization set in, stirred for 30 minutes and then cooled to 0° C. The slurry was filtered off, the reactor and filter cake were rinsed with methanol (816 mL, 2 vol) previously cooled to 0-5° C. The filter cake was dried under vacuum for 30 minutes. The solid was then returned to the reactor and stirred with a 1:3 methanol:water mixture (4.1 L, 10 vol) at 22° C. for 24 hours. Methanol (2.05 L, 5 vol) was added to the reactor, resulting in a 1:1 methanol:water mixture. This solution was then stirred for an additional 24 hours, after which the mixture was filtered, and the cake was rinsed with water (818 L, 2 vol). The solids were transferred to a vacuum oven and dried at 38° C. to give Compound 10 as a white solid.
Example 7
Alternative Route to 2-(2,4-difluorophenyl-1)-6-(2,6-difluorophenylamino)nicotinic acid (9)
Step A: Saponification:
A 250 mL round bottom flask was charged with Compound 5 and THF at room temperature. A 1M LiOH solution was then added to flask. The resulting mixture was heated to approximately 40° C. for about 3 hours and then cooled down room temperature and stirred for about 2 days. The reaction can be monitored by HPLC. After stirring, the mixture was transferred to a separatory funnel, 100 mL DCM was added, and the mixture was washed with 100 mL water. The organic layer was separated and aqueous phase was neutralized with 110 mL aqueous 1N HCl and extracted with DCM (3×100 mL). The organic layers were combined and concentrated to provide Compound 11 as a white solid. H NMR (500.0 MHz, DMSO) 13.5 (bs, OH) d 8.31 (d, J=8.3 Hz, H), 7.70 (d, J=8.2 Hz, H), 7.62 (dd, J=8.6, 15.2 Hz, H), 7.35-7.31 (m, H), 7.21 (td, J=8.5, 3.6 Hz, H), 3.33 (s, H), 2.51 (d, J=1.7 Hz, H) ppm.
Step B: Coupling
A 100 mL round bottom flask was charged with Compound 20 (1.0015 g, 3.714 mmol) in MBTE (10 mL) followed by the addition of Compound 6 (600 μL, 5.572 mmol). The resulting mixture was cooled to an internal temperature of −8° C. to −10° C. with an ice/acetone bath followed by the dropwise addition (over 1 hour) of a 1 M solution of potassium bis(trimethylsilyl)amide (9.3 mL, 9.300 mmol) while maintaining the mixture temperature at less than about −5° C. After the addition of the base, the reaction mixture was quenched with 20 mL 1 M HCl at room temperature. The mixture was washed with 20 mL water and 50 mL ethyl acetate. The aqueous phase was washed at least once more with ethyl acetate. The organic layer was concentrated followed by the addition of DCM (25 mL). The resulting solids were suspended, filtered, and washed with 50 mL DCM. Analysis of the solids confirmed the presence of Compound 9.
In other embodiments the base used in the coupling step can also be selected from LiHMDS (55° C.), NaHMDS (55° C.), KOtBu, and nBuLi.
Example 8
Alternative Route to 2-(2,4-difluorophenyl)-6-(1-(2,6-difluorophenyl)ureido)nicotinamide (10)
In some embodiments, Compound 10 can be produced by stepwise formation of amide Compound 12 using CDI, THF, NH 4 OH or toluene/Methylchloroformate/NEt 3 /NH 4 OH. Compound 10 can be subsequently formed by treating Compound 15 with chlorosulfonylisocyanate in a solvent such as CH 3 CN, DMSO, MeTHF, THF, DMF, or DMSO.
Other Embodiments
All publications and patents referred to in this disclosure are incorporated herein by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Should the meaning of the terms in any of the patents or publications incorporated by reference conflict with the meaning of the terms used in this disclosure, the meaning of the terms in this disclosure are intended to be controlling. Furthermore, the foregoing discussion discloses and describes merely exemplary embodiments of the present invention. One skilled in the art will readily recognize from such discussion and from the accompanying drawings and claims, that various changes, modifications and variations can be made therein without departing from the spirit and scope of the invention as defined in the following claims. | The present invention relates to processes for the preparation of compounds useful as inhibitors of p38 kinase. The processes of the present invention are amenable for large scale preparation and produce stable phenyl-6-(1-(phenyl)ureido)nicotinamides in high purity and yields. | 2 |
FIELD OF THE INVENTION
The present invention relates to methods and molecules for treating asthma. The present invention provides short nucleotide sequences and vectors comprising these sequences that can inhibit AMCase (acidic mammalian chitinase) expression in mammalian.
BACKGROUND OF THE INVENTION
Asthma has become a serious public health issue worldwide, and its prevalence has doubled in numerous industrialized countries (Beasley et al., J Allergy Clin Immunol 2000; 105, S466-472). Chronic airway inflammation characterized by pathological immune response is considered the hallmark of asthma. The key features of asthma include the production of allergen-specific IgE, resulting in immediate-type hypersensitivity reactions followed by the development of late phase responses such as eosinophil recruitment, mucus production, and airway hyperresponsiveness (AHR). In addition, eosinophilic inflammation driven by Th2-cytokines (including IL-4, IL-5 and IL-13) is deemed to play a crucial role in the pathogenesis of asthma (Renauld et al., J Clin Pathol 2001; 481:54, 577-589; Hoshino et al., Int Immunol 2004; 16, 1497-1505). Particularly, several studies have highlighted the crucial contribution of IL-13 in promoting the development of asthmatic features.
Acidic mammalian chitinase (AMCase), the prototypic chitinase, has been found to be induced during Th2-mediated inflammation through an IL-13-dependent mechanism (Kawada et al., Keio J Med 2007; 56, 21-27). It is a 50-kDa protein, containing a 39-kDa N-terminal catalytic domain that hydrolyzed chitin, a hinge region, and a C-terminal chitin-binding domain. AMCase is highly expressed in the lungs of asthmatic patients, as well as in mice models of asthma (Ramanathan et al., Am J Rhinol 2006; 20:479, 330-335). In fact, the hyper-expression of AMCase has also been found in the other airway tissues including the alveolar macrophages and lung epithelial cells in OVA-stimulated mice (Zhu et al., Science 2004; 304, 1678-1682). Inhibition of AMCase activity with specific antibodies appeared to be able to reduce the inflammatory response in BALF and lung tissues. However, neutralization of AMCase activity does not directly affect the expression of IL-4 and IL-13 (Zhu et al., Science 2004; 304, 1678-1682). It was found that AMCase could modulate the expression of several proinflammatory chemokines-including macrophage inflammatory protein (MIP)-1β, macrophage chemoattractant protein (MCP)-1 and eotaxin that play a crucial role in Th2-mediated airway inflammation (Mori, et al. Int Arch Allergy Immunol 2006; 140 Suppl 1, 55-58).
RNA interference (Fire, et al. Nature 1998; 391, 806-811) has become a powerful tool in downregulation of gene expression in mammalian cells and animal models (Cullen, et al. Gene Ther 2004; 13, 503-508). Recent studies have shown that short interfering (21-25 bp) RNA molecules (siRNA—small interfering RNA), but not long dsRNA (greater than 30 bp), are key elements of RNAi and appear to inhibit gene expression. Short hairpin RNA (shRNA) has been shown to be efficiently processed into siRNA inside the cells. In the last few years, some methods for expressing siRNAs in cells have been developed based on transcription of short hairpin RNAs (shRNAs) by RNA polymerase III promoter (Sui et al., Proc Natl Acad Sci USA 2002; 99, 5515-5520), such as U6 and H1. Delivery of siRNA into mammalian cells has been achieved via liposome, polymer and viral vectors. (Moore et al., J Gene Med 2005; 7, 918-925; Urban-Klein et al., Gene Ther 2005; 12, 461-466; Xu et al., Mol Ther 2005; 11, 523-530; Li et al., Cell Cycle; 5, 2103-2109; Aigner et al., Curr Opin Mol Ther 2007; 9, 345-352). Viral vectors appear to have the highest delivery efficiency. A serious problem with viral vectors is their immunogenity. In this regard, repeated applications may result in the production of neutralizing antibodies by the host. To overcome this issue, the use of adeno-associated virus (AAV), which promotes longterm transgene expression, has been proposed. AAV vector offers a compromise between an adequate level of transduction and an acceptable safety profile (Leung et al., J Gene Med 2007; 9, 10-21). Hence, several reports have successfully used AAV-mediated shRNA therapeutic system in controlling viral infections (Ge et al., Proc Natl Acad Sci USA 2004; 101, 8676-8681) and genetic disorders Rodriguez-Lebron et al., Mol Ther 2005; 12, 618-633). In the present study, we demonstrated that specific suppression of elevated AMCase results in a reduced eosinophilic and Th2-mediated airway inflammation in a mouse model of asthma. We also investigated whether the inhibition of AMCase may be associated with a reduced expression of IL-13, eotaxin, and other proinflammatory molecules.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 . Inhibitory effects of pCI-shRNA and rAAV-mediated shRNA on AMCase expression. (a). Representative Western blot of an AMCase-overexpres sing stable cell line treated by pCI-shRNA 1336 for 48 hours. (b). AMCase expression of the same cell line following infection with rAAV vector expressing shRNA1336, and harvested on days 0, 2, 4, 6, and 8. Western blots using anti-AMCase and anti-actin antibodies are shown.
FIG. 2 . AMCase expression quantified via (a) real-time PCR and (b) Western blot in normal saline controls (n=5) and OVA-sensitized mice (n=9). Cytology samples from lung tissues, BALF, and the peritoneal cavity were harvested. For panel (a), mRNA levels of AMCase expression detected by real-time RT-PCR were normalized to actin and compared with normal controls. For panel (b), AMCase protein levels were analyzed by Western blot (*p<0.05, nonparametric Mann-Whitney test).
FIG. 3 . Airway hyperrsponsiveness inhibited in rAAV-shRNA-treated mice. Panel (a), schematic protocol for rAAV treatment flowchart. Mice were sensitized and treated as described in the Methods. Panel (b), Airway hyperrsponsiveness was measured by whole body plethysmography. Data were expressed as Penh values. Normal saline controls (normal, n=4), sensitized mice (n=10), OVA sensitized mice receiving rAAV-GFP (n=4) and rAAV-shRNA1336 (n=7) (*p<0.05, nonparametric Mann-Whitney test). IH: inhalation; IP: intraperitoneal; IT: intratracheal.
FIG. 4 . Suppression of AMCase in lung tissues and BALF cells of rAAV-shRNA-treated mice. Panel (a), real-time PCR was performed to quantify AMCase mRNA in lung tissues and BALF cells. Data were normalized to actin and compared with normal controls. Panel (b), expression of AMCase in the lung as detected by IHC. Panel (c), AMCase activity in BALF cells measured by fluorogenic chitin substrate. Normal (normal, n=7), sensitized (n=7), rAAV-GFP (n=8) and rAAV-shRNA1336 (n=10) were investigated (*p<0.05, nonparametric Mann-Whitney test).
FIG. 5 . Reduction of immunopathological responses in rAAV-shRNA-treated mice. Panel (a), serum levels of OVA-specific IgE were measured by ELISA. Panel (b), the number of eosinophils within BALF was calculated by microscopy at 400× magnification. Panel (c) H&E histopathology of the lung analyzed by microscopy at 100× and 400× magnifications. Normal (n=7), sensitized (n=7), rAAV-GFP (n=10) and rAAV-sh1336 (n=11) were investigated (*p<0.05, nonparametric Mann-Whitney test).
FIG. 6 . Expression of cytokines and chemokines in rAAV-shRNA-treated mice. Panels (a) and (b) show levels of IL-13 and eotaxin measured by ELISA in BALF samples. Panel (c), RNA samples from lung tissues were analyzed for cytokine and chemokine gene expression by means of RT-PCR. Normal (n=3-7), sensitized (n=5-7), rAAV-GFP (n=6-10) and rAAV-sh1336 (n=6-11) were investigated (*p<0.05, nonparametric Mann-Whitney test).
SUMMARY OF THE INVENTION
The invention includes the small interfering RNA polynucleotide that could treat asthma and the vectors comprising them, which also include the method of administrating the vector to a subject.
An isolated small interfering RNA (siRNA) polynucleotide, comprising at least one polynucleotide that is selected from the group consisting of (i) a polynucleotide having the nucleotide sequence set forth in SEQ ID NO: 1 or (ii) a polynucleotide having the nucleotide sequence set forth in SEQ ID NO: 2 or (iii) a polynucleotide having the nucleotide sequence set forth in SEQ ID NO: 3.
A composition comprising: an siRNA or a small hairpin RNA or short hairpin RNA (shRNA) targeted to a target transcript, or a nucleic acid that comprises a template for transcription of one or more RNA molecules that hybridize or self-hybridize to form an siRNA or shRNA targeted to a target transcript, wherein the target transcript encodes a protein named acidic mammalian chitinase (AMCase) involved in airway hyper responsiveness and inflammation in mammalian.
A method for treating asthma of a subject, comprising steps of: administrating the subject with a therapeutically composition which is a pharmaceutical acceptable carrier of aforementioned; and the way to administrate the subject with the therapeutically composition is through inhalation.
DETAILED DESCRIPTION OF THE INVENTION
The potential therapeutic applications of RNAi technology to down regulate gene expression have been widely evaluated. Unfortunately, only a few reports have focused on RNAi-based treatment for asthma (Lee et al., Mol Ther 2008; 16, 60-444 65; Lively et al., J Allergy Clin Immunol 2008; 121, 88-94.), an emergent worldwide health issue (Beasley et al., J Allergy Clin Immunol 2000; 105, S466-472). In the present study, we have shown that AMCase expression can be effectively down regulated by means of rAAV-mediated shRNA. Reduction of AMCase expression resulted in an improvement of the asthmatic inflammatory response in OVA-sensitized asthmatic mice. Altogether, these findings suggest the potential usefulness of RNA interference targeting AMCase as a novel therapeutic strategy in asthma. This possibility is in keeping with previous findings showing that AMCase may play a key role in IL-13-mediated responses occurring in asthma. (Zhu et al., Science 2004; 304, 1678-1682).
Cytokines are known to play an important role in asthma, including pulmonary eosinophilia, serum IgE elevation, and excessive mucus production (Wills-Karp and Karp, N Engl J Med 2004; 351, 1455-1457). In this study we have shown that rAAV-shRNA-treated mice showed a significantly reduced IL-13 expression in their BALF (bronchoalveolar lavage fluid). This reduction was directly correlated to AMCase inhibition in BALF cells. In contrast, only a minor effect on IL-4 and IL-5 expression was seen in lung tissues. Notably, rAAV-shRNA suppressed the induction of AMCase expression by IL-13 in mouse lung epithelial cells. In this regard, Zhu et al. have previously shown a significant hyper-expression of AMCase in IL-13 transgenic mice (Zhu et al., Science 2004; 304, 1678-1682). On the other hand, IL-13-null mice failed to express AMCase following an allergen challenge (Zhu et al., Science 2004; 304, 1678-1682). These findings highlight the inter-independence between IL-13 and AMCase in the pathogenesis of asthmatic inflammation. It has been also previously suggested that AMCase could regulate the expression of several chemokines (eotaxin, MCP-1 and MIP-1β) in asthma. (Zhu et al., Science 2004; 304, 1678-1682) Eotaxin is a chemo attractant for eosinophils in the lung following an allergen challenge (Conroy and Williams, Respir Res 2001; 2, 150-156; Zimmermann et al., J Allergy Clin Immunol 2003; 111, 227-242), but the exact relationship between AMCase expression and eotaxin remains unclear. MCP-1 and MIP-1β are thought to play a role in the airway inflammation. Accordingly, several reports have shown elevated levels of MCP-1 and MIP-1β in asthmatic subjects. (Zhu et al., Science 2004; 304, 1678-1682). In the present invention, inhibition of AMCase in OVA asthmatic mice led to a reduction in eotaxin expression in their BALF. This result is keeping with the low number of eosinophils detected in BALF. Moreover, expression of eotaxin, MCP-1 and MIP-1β was also remarkably reduced after treatment with AAV-shRNA.
To overcome poor siRNA transfection rates in vivo, we used the AAV vector as a delivery tool for shRNA in keeping with similar studies on bronchial diseases (Zavorotinskaya et al., Mol Ther 2003; 7, 155-162; Flotte, Curr Gene Ther 2005; 5, 361-366; Leung et al., J Gene Med 2007; 9, 10-21). Murphy and coworkers have previously compared the efficacy of a single intramuscular injection versus intratracheal administration of a rAAV vector carrying the IL-4 receptor antagonist in OVA-sensitized mice. The authors showed that intratracheal administration resulted in significant local effects in the airways, with no systemic or local adverse effects (Zavorotinskaya et al., Mol Ther 2003; 7, 155-162). Accordingly, the AAV vector achieved a better transfection rate not only in vivo, but also in vitro. In the present study, a liposome-based transfection with pCI-shRNA resulted in an AMCase inhibition of approximately 85%, whereas suppression rate of almost 100% was achieved by rAAV-shRNA. These data clearly indicate that rAAV may be regarded as an optimal transfection vector.
Example 1
Reduction of AMCase Expression Levels by Hairpin-Type siRNA
The example expresses the effect of reducing AMCase expression levels by hairpin-type siRNA and rAAV mediated shRNA1336. The siRNA nucleotide sequences specific for AMCase were selected from three candidates.
Three sequences specifically targeting murine AMCase were designed as siRNA185 (SEQ ID NO: 1), siRNA897 (SEQ ID NO:2) and siRNA1336 (SEQ ID NO:3), shRNA molecules with the same sequences as siRNA, but containing an 8 random nucleotides (CAAGCTTC) loop structure and a 3′ TTTT terminator nucleotides overhanging at 3′-end were inserted into a pCI-neo plasmid vector with a mU6 promoter.
These three hairpin-type siRNA expression vector containing the mouse U6 promoter were constructed (pCI-shRNA185, pCI-shRNA897 and pCI-shRNA1336). Their ability to suppress AMCase expression was tested in stable cell lines overexpressing AMCase.
The AMCase overexpressing cell line was set up by the following steps: RNA was extracted from mouse lung tissues using the TriZol reagent (Invitrogen) and reversely transcribed (RT) with a two-step RT-polymerase chain reaction (PCR) kit (Invitrogen). The full length AMCase sequence was amplified with the following primers: forward 5′-ATC AGAATTCTAT GGC CAA GCT ACT TCTC-3′ (SEQ ID NO: 4), and reverse 5′-TTT CTG CGG CCGCAT GGC ATT AGG TTC ATG GC-3′ (SEQ ID NO:5). The AMCase overexpressing cell line was established by transfection to 3T3 cells of a pTriEx-neo vector containing the AMCase sequence. A dilution series under G418 selection pressure was applied.
The three shRNA constructs were packed by Lipofetamine 2000 and send to AMCase overexpressing cells. All three constructs were able to reduce AMCase expression at different extents. Specifically, AMCase expression was reduced by 85% with shRNA1336, by 50% with shRNA185 and by 20% with shRNA 897 ( FIG. 1 a ).
Example 2
Reduction of AMCase Expression Levels by rAAV Mediated shRNA1336
Secondly, AAV vectors encoding GFP and shRNA1336, rAAV-GFP, and rAAV-shRNA1336 were cloned and tested for their inhibitory effects on AMCase expression.
The shRNA1336 was subcloned into an adeno-associated virus vector pAAV2-IRES-GFP. Virus production was performed with the AAV2 helper system (Stratagene). Briefly, plasmid DNA (rAAV-shRNA1336-IRES-GFP plasmid plus the pRC vector encoding Rep and Cap proteins and the pHelper vector encoding adenovirus gene products) was used to transfect 293T cells at an 80% confluence stage. Cell lysates were collected 48 hours post-transfection and purified by CsCI density gradient centrifugation. Titers of rAAV-shRNA1336-IRES-GFP were determined using RT-PCR analysis by calculating the viral genome copy number. Expression of GFP and actin were analyzed by real-time PCR using a Light-Cycler PCR system (Roche). Actin 300 was used as a housekeeping gene, and its' forward primer: 5′-GAAACTACATTCAATTCCATC-3′ (SEQ ID NO: 6); reverse primer: 5′-CTAGAAGCACTTGCGGTGCAC-3′ (SEQ ID NO: 7).
The reaction parameters for actin 300 and GFP amplification (forward primer: 5′-ATGGTGAGCAAGCAGATCCTG-3′(SEQ ID NO:8); reverse primer: 5′-GGTGCGCTCGTACACGAAGCC-3′ (SEQ ID NO:9)) were as follows: initial denaturation at 95° C. for 10 min, followed by 35 cycles at 95° C. for 10 s, 50° C. for 10 s, and 72° C. for 10 s.
Infection with rAAV-shRNA1336 significantly suppressed AMCase expression in the stable cell line between days 2 and 8 ( FIG. 1 b ). Altogether, these findings indicate that rAAV-shRNA1336 showed the better long-term effect on the reduction of AMCase expression.
Example 3
Develop an OVA (Ovalbumin) Sensitized Mice
Pathogen-free wild type female BALB/C mice from the National Laboratory Animal Centre (Taipei, Taiwan, ROC) were used in this study. Mice were 6-8 weeks old at the beginning of the experiment. Animals were maintained and handled according to the guidelines of Animal Care Committee of Chang Gung University and the NIH Guidelines for the Care and Use of Laboratory Animals. Mice were injected intraperitoneally with either chicken OVA (20 μg) complexed with alum or normal saline alone. The procedure was repeated 3 days thereafter. Thirteen days after the first immunization, animals were re-injected intraperitoneally with chicken OVA. Moreover, mice received by inhalation either an aerosol of OVA (2%, w/v) in normal saline or normal saline solution alone. Mice were thereafter challenged with OVA for four times on days 16, 20, 23, and 27. On day 25, 1.0×10 11 genome copies of rAAV-shRNA1336-IRES-GFP, rAAV-IRES-GFP or normal saline solution were administered intratracheally. Mice were sacrificed on day 28.
On day 28, 24 hr after the last challenge, the mice airway responsiveness was measured by whole body plethysmography (Buxco, Troy, N.Y.) (Lee et al., Mol Ther 2008; 16, 60-65). Briefly, mice were aerosolized normal saline or methacholine in increasing concentrations (0, 6.25, 12.5, 25, 50 mg/ml) for 3 minutes. Recordings were taken and averaged for 3 minutes after each nebulization. Airway reactivity was expressed as the mean Penh.
Example 4
Determination of OVA-Specific IgE in Mice Serum
Serum levels of OVA-specific IgE were measured by enzyme-linked immunosorbent assay (ELISA). Briefly, 96-well plates (Maxisorb, Nunc) were coated with OVA (10 Zg/ml) and blocked. After addition of serum samples at proper dilutions, biotin-conjugated rat-anti-mouse IgE was added to individual wells. The reaction was developed with Streptavidin-HRP. Substrate solution was then added to each well and the plates were incubated for 30 min at room temperature in a dark room. After addition of a stop solution, the absorbance was read with an ELISA plate reader at 450 nm. IgE concentrations were determined using a commercial mouse IgE standard (BD Pharmingen).
Example 5
Levels of AMCase in BALF and Lungs of Ova-Sensitized Asthmatic Mice
To investigate whether elevated levels of AMCase expression are specifically located in the airway tissues of OVA-sensitized mice, the lung tissues, BALF, and peritoneal cells were harvested on day 28, 24 hours from the last OVA-challenge. Notably, a 17-fold and 37-fold increase in AMCase mRNA level was found in the lung tissues and BALF of OVA-sensitized mice, respectively. In contrast, no difference was found in peritoneal cells as compared with control experiments with normal saline ( FIG. 2 a ). Similar findings were obtained when AMCase protein levels were measured.
FIG. 2 b shows significantly higher levels of AMCase only in lung tissue and BALF cells from OVA-sensitized mice. In peritoneal cells, such an increase was not found both at the mRNA and protein level. Thus, hyper expression of AMCase was limited to airway tissues of mice with allergic asthma.
Example 6
Reduction of AHR (Airway Hyper Responsiveness) and AMCase Expression in the Airways of OVA-Sensitized Mice Following rAAV-shRNA1336 Administration
Since hyperexpression of AMCase was limited to airway tissues of mice with allergic asthma, we investigated whether rAAV-shRNA may prevent AMCase hyperexpression and allergic reactions. FIG. 3 a depicted a schematic representation of the rAAV treatment protocols. After three days from intratracheal administration of 1011 rAAV encoding LacZ or GFP (rAAV-LacZ, rAAV-GFP), rAAV infection was evident in mice lung tissues and BALF cells. Mice were sacrificed for analysis on day 3 following rAAV infections. FIG. 3 b showed that methacholine induced the significant increase of AHR in OVA-sensitized mice without further treatment or with rAAV-GFP. After the mice treating with rAAV-shRNA1336, their Penh values in responding to the induction of methacholine were dropped, similar to the ones of normal mice. FIG. 4 a showed that AMCase expression was reduced by 2-fold in lungs and by 3-fold in BALF cells of mice treated with rAAV-shRNA1336 compared with mice receiving rAAV-GFP; however, both groups of OVA-sensitized mice showed relative higher levels of AMCase compared to normal saline experiments. AMCase protein levels or activity in lungs and BALF cells were also investigated by means of IHC or enzymatic assays using commercially fluorescence systems. FIG. 4 b showed that AMCase was mainly expressed in the airway epithelial cells of OVA-sensitized animals receiving rAAV-GFP, while lower levels of AMCase expression were seen in rAAV-shRNA1336-treated animals. It is thus posited that a significant reduction in AMCase expression occurs following rAAV-shRNA infection. As it can be seen in FIG. 4 c , AMCase activity was found to be inhibited in BALF cells of mice treated with rAAV-shRNA1336.
Example 7
rAAV-shRNA1336 Reduced Immunopathological Reactions in OVA Asthmatic Mice
Treatment with rAAV-shRNA1336 resulted in a significant reduction in immunopathological allergic responses among OVA-sensitized mice. Firstly, OVA specific IgE serum level appeared to be significantly lower in asthmatic mice treated with rAAV-shRNA compared to animals treated with rAAV-GFP ( FIG. 5 a ). Secondly, infection with rAAV-shRNA reduced eosinophil infiltration in BALF ( FIG. 5 b ) as well as infiltration of inflammatory cells in the lung tissues of asthmatic mice ( FIG. 5 c ). IL-13 was a cytokine whose expression has been associated with AMCase expression and eotaxin, an eosinophil specific chemo-attractant. Levels of IL-13 and eotaxin were measured in BALF cells using commercially available ELISA kits. As shown in FIGS. 6 a and 6 b , concentrations of IL-13 and eotaxin concentrations were lower in mice treated with normal saline only. In contrast, OVA-sensitized mice treated by rAAV-GFP had higher levels of IL-13 and eotaxin compared with OVA-sensitized mice receiving rAAV-shRNA. Altogether, these findings suggest that rAAV-shRNA can reduce levels of IL-13 and eotaxin. Other Th2-associated cytokines (IL-4 and IL-5) were also measured and inflammatory chemokines (MCP-1 and MIP-1β) in lung cells of mice receiving different rAAV treatments. RNA samples from lung tissues of mice receiving normal saline were used as negative controls. The main findings are depicted in FIG. 6 c . Treatment with rAAV-shRNA resulted in a reduced expression of all cytokine and chemokine genes in the lung, although IL-4 and IL-13 inhibition was not as prominent as that observed with chemokines (eotaxin, MCP-1 and MIP-1β). A relatively reduced expression of IL-5 in the lung was also found. | The invention provides small interfering RNA (siRNA) and their carriers that could treat asthma in mammalian through inhibiting acidic mammalian chitinase (AMCase) gene expression. The invention further provides a composition comprising siRNA of the present invention and a carrier. The invention also provides a method for treating asthma of a subject. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation-In-Part claiming priority benefit from U.S. patent application Ser. No. 11/282,046 which was filed on Nov. 16, 2005.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention relates, in general, to the field of motion tracking, and in particular to head tracking in a magnetic resonance imaging application. In particular the invention teaches an apparatus and method to track the movement of a target in three-dimensional space during medical imaging scanning using optical technology. The invention further comprises an apparatus and method to use the head tracking data to control the magnetic field gradients and/or radio frequency fields of the magnetic resonance imaging instrument thereby maintaining active image registration during the scans.
BACKGROUND OF THE INVENTION
[0003] Computerized tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET), coupled with developments in computer-based image processing and modeling capabilities have led to significant improvements in the ability to visualize anatomical structures in human patients. This information has become invaluable in the diagnosis, treatment, and tracking of patients. The technology has been recently been expanded to be used in conjunction with real-time interventional procedures.
[0004] MRI is the method of creating images (referred to as MR images) of the internal organs in living organisms. The primary purpose is demonstrating pathological or other physiological alterations of living tissues. MRI has also found many niche applications outside of the medical and biological fields such as rock permeability to hydrocarbons and certain non-destructive testing methods such as produce and timber quality characterization. Superb image contrast for soft tissues and millimeter scale spatial resolution has established MRI as a core imaging technology in most medical centers. MRI is unique among imaging modalities in that any one of a multitude of tissue properties can be extracted and highlighted.
[0005] The MRI process requires a highly accurate and stable target which to image. This is a consequence of the process by which medical MRI functions. Medical MRI most frequently relies on the relaxation properties of excited hydrogen nuclei in water. When the object to be imaged is placed in a powerful, uniform magnetic field, the spins of the atomic nuclei with non-zero spin numbers within the tissue all align in one of two opposite directions: parallel to the magnetic field or antiparallel.
[0006] The difference in the number of parallel and antiparallel nuclei is only about one in a million. However, due to the vast quantity of nuclei in a small volume, the nuclei sum to produce a detectable change in field strength. The magnetic dipole moment of the nuclei then moves in a gyrating fashion around the axial field. While the proportion is nearly equal, slightly more nuclei are oriented at the low energy angle. The frequency with which the dipole moments process is called the Larmor frequency. The tissue is then briefly exposed to pulses of electromagnetic energy (RF pulse) in a plane perpendicular to the magnetic field, causing some of the magnetically aligned hydrogen nuclei to assume a temporary non-aligned high-energy state.
[0007] In order to selectively image the different voxels (3-D pixels) of the material in question, three orthogonal magnetic gradients are applied. The first is the slice selection, which is applied during the RF pulse. Next comes the phase encoding gradient, and finally the frequency encoding gradient, during which the tissue is imaged. Most of the time, the three gradients are applied in the X, Y, and Z directions of the machine. As a consequence of this methodology, any small shift in the position of the patient with respect to these fixed gradient axes will alter the orientations and positions of the selected slices.
[0008] In order to create an MR image, spatial information must be recorded along with the received tissue relaxation information. For this reason, magnetic fields with an intensity gradient are applied in addition to the strong alignment field to allow encoding of the position of the nuclei. A field with the gradient increasing in each of the three dimensional planes is applied in sequence. This information is then subsequently subjected to a Fourier transformation by a computer that transforms the data into the desired image and yields detailed anatomical information results.
[0009] With conventional anatomic MR imaging, the presence of moving biological tissue is problematic. The tissue produces image artifacts, degrades the quality of the images, and complicates the interpretation of MR images. The typical appearance of such image artifacts takes the form of “blurring,” or a characteristic “motion ghost” in the phase encoding direction associated with incorrectly encoding the spatial frequencies of a moving object that is assumed to be static.
[0010] The typical medical resolution is about 1 mm, while research models can exceed 0.1 mm. Through the process of MRI, anatomy can be defined in great detail, and several other biophysical and metabolic properties of tissue, including blood flow, blood volume, elasticity, oxygenation, permeability, molecular self-diffusion, anisotropy, and water exchange through cell membranes, can also be represented. Conventional anatomical MR imaging uses this spin-echo, gradient-echo, and inversion recovery sequencing. There are other methods of MR that are currently being used, including magnetic resonance spectroscopy (MRS), apparent diffusion coefficient (ADC) mapping, diffusion-weighted imaging (DWI) and its derivatives of diffusion tensor imaging and tractography, perfusion imaging, permeability imaging, MR angiography (MRA), and functional MRI (fMRI). As the techniques of MR become more precise, there is corresponding need for increased accuracy and the tracking of the patient during the MR procedure. See E. Fukushima and S. B. W. Roeder, Experimental Pulse NMR Addison-Wesley, Reading, M A 1981; T. C. Farrar, An Introduction To Pulse NMR Spectroscopy Farragut Press, Chicago, 1987; R. C. Jennison, Fourier Transforms and Convolutions Pergamon Press, NY 1961; E. O. Brigham, The Fast Fourier Transform Prentice-Hall, Englewood Cliffs, NJ 1974; and A. Carrington A. D. McLachlan, Introduction To Magnetic Resonance Chapman and Hall, London 1967 which are each hereby incorporated by reference.
[0011] Functional MRI (fMRI) measures signal changes in the brain that are due to changing neural activity. This scan is completed at a low resolution but at a very rapid rate (typically once every 1-3 seconds). Increases in neural activity cause changes in the MR signal via a mechanism called the BOLD (blood oxygen level-dependent) effect. Increased neural activity causes a corresponding increased demand for oxygen, which is responded to by the vascular system, which increases the amount of oxygenated relative to deoxygenated hemoglobin. Because deoxygenated hemoglobin attenuates the MR signal, the vascular response leads to a signal increase that is related to the neural activity. The use of MRI to measure physiologic and metabolic properties of tissue non-invasively requires dynamic imaging to obtain time-series data.
[0012] One example of the use of fMRI is to measure brain activity. This use relies on a well-established neurovascular coupling phenomenon that results in transient increases in blood flow, oxygenation, and volume in the vicinity of neurons that are functionally activated above their baseline level. Signal changes due to the blood oxygenation-level-dependent (BOLD) effect are intrinsically weak (only several percent signal change from baseline at 4.0 T or less). In addition, as BOLD imaging is typically coupled with a repetitive behavioral task (e.g., passive sensory, cognitive, or sensorimotor task) to localize BOLD signals in the vicinity of neurons of interest, there is significant potential for fMRI to be confounded by the presence of small head motions. Specifically, such motion can introduce a signal intensity fluctuation in time due to intra-voxel movement of an interface between two different tissues with different MR signal intensities, or an interface between tissue and air. Random head motion decreases the statistical power with which brain activity can be inferred, whereas task-correlated motion cannot be easily separated from the fMRI signal due to neuronal activity, resulting in spurious and inaccurate images of brain activation. In addition, head motion can cause mis-registration between neuroanatomical MR and fMR images that are acquired in the same examination session. This latter point is important because the neuroanatomical MRI data serve as an underlay for fMRI color maps, and mis-registration results in mis-location of brain activity. An analogous problem exists for aligning anatomical and functional MR images performed on different days.
[0013] Lack of motion in current MRI examinations anatomic motion is not merely preferred, but is instead absolutely essential. Most aspects of human motor system performance require the patient to execute a movement as part of the behavioral task that is imaged to visualize brain activity. Movements can be very simple (e.g., self-paced finger tapping) or more complex (e.g., visually-guided reaching). Such examinations require both that the desired movement is performed in a well-controlled or well-quantified fashion, and also that the movement does not induce task-correlated head motion that confounds the ability to observe brain activity using fMRI. Perhaps the most complicated scenario involves combining use of virtual reality (VR) technology with fMRI, to determine brain activity associated with VR tasks for assessment and rehabilitation of impaired brain function. Such applications are important from the standpoint of “ecological validity” as they provide the opportunity to visualize brain activity associated with tasks that generalize well to everyday behavior in the real 3D-world. For example, position tracking would be required to provide realistic visual representation of a virtual hand operated by a data glove in a virtual environment.
[0014] The problem of motion tracking within an fMRI environment has been well documented in published medical literature describing various aspects of motion detection and quantitation. See Seto et al., NeuroImage 2001, 14:284-297; Hajnal et al., Magn Res Med 1994, 31: 283-291; Friston et al., Magn Res Med 1996, 35:346-355; Bullmore et al., Human Brain Mapping 1999, 7: 38-48; Bandettini et al., Magn Res Med 1993, 30:161-173; Cox. Comp Med Res 1996, 29:162-173; Cox et al., Magn Res Med 1999, 42:1014-1018; Grootoonk et al., NeuroImage 2000, 11:49-57; Freire et al., IEEE Trans Med Im 2002, 21(5):470-484; Babak et al., Magn Res Im 2001, 19:959-963; Voklye et al. 1999, Magn Res Med 41:964-972, which are each incorporated by reference.
[0015] As the clinical applications of MRI expand, there is a concurrent requirement for improved technology to visualize and determine the position and orientation of moving objects in the imaging field. Improvements in position tracking technology are required to advance the resolution and quality of the MRI, including the ability to image the anatomy of a patent, the imaging of tissue functions, the use of MRI data for other imaging modalities, and interventional applications.
[0016] For anatomical and functional MRI applications, as well as interventional MRI, there is the additional need to register data from other imaging modalities to provide comprehensive and complementary anatomical and functional information about the tissue of interest. The registration is performed either to enable different images to be overlaid, or to ensure that images acquired in different spatial formats (e.g., MRI, conventional x-ray imaging, ultrasonic imaging) can be used to visualize anatomy or pathology in precisely the same spatial location. While some algorithms exist for performing such registrations, computational cost would be significantly reduced by developing technology that enables data from multiple different imaging modalities to be inherently registered by measuring the patient's orientation in each image with respect to a common coordinate system.
[0017] By detecting, tracking, and correcting for changes in movement, data acquisition can be synchronized to a specific target. As a consequence, MR data acquisition is gated to a specific position of the target, and by implication, to a specific position of a specific target region.
[0018] U.S. Pat. No. 6,067,465 to Foo, et al. discloses a method for detecting and tracking the position of a reference structure in the body using a linear phase shift to minimize motion artifacts in magnetic resonance imaging. In one application, the system and method are used to determine the relative position of the diaphragm in the body in order to synchronize data acquisition to the same relative position with respect to the abdominal and thoracic organs to minimize respiratory motion artifacts. The time domain linear phase shift of the reference structure data is used to determine its spatial positional displacement as a function of the respiratory cycle. The signal from a two-dimensional rectangular or cylindrical column is first Fourier-transformed to the image domain, apodized or bandwidth-limited, converted to real, positive values by taking the magnitude of the profile, and then transformed back to the image domain. The relative displacement of a target edge in the image domain is determined from an auto-correlation of the resulting time domain information.
[0019] There is often a need in neuroimaging to look for changes in brain images over long periods of time, such as the waxing and waning of MS lesions, progressive atrophy in a patient with Alzheimer's disease, or the growth or remission of a brain tumor. In these cases, the ability to determine the position of anatomy as a function of time is extremely important to detect and quantify subtle changes. High-spatial resolution is a basic requirement of 3D brain imaging data for patients with neurological disease, and motion artifacts a consequence of movement during scanning pose a significant problem. If a patient does not stay completely still during MR neuroimaging the quality of the MR scan will be compromised.
[0020] Many of the advantages of MRI that make it a powerful clinical imaging tool are also valuable during interventional procedures. The lack of ionizing radiation and the oblique and multi-planar imaging capabilities are particularly useful during invasive procedures. The absence of beam-hardening artifacts from bone allows complex approaches to anatomic regions that may be difficult or impossible with other imaging techniques such as conventional CT. Perhaps the greatest advantage of MRI is the superior soft-tissue signal contrast available, which allows early and sensitive detection of tissue changes during interventional procedures.
[0021] MR is used for procedures such as “interventional radiology”, where images produced by an MRI scanner guide surgeons in a minimally invasive procedure. However, the non-magnetic environment required by the scanner, and the strong magnetic radiofrequency and quasi-static fields generated by the scanner hardware require the use of specialized instruments. Exemplary of such endoscopic treatment devices are devices for endoscopic surgery, such as for laser surgery disclosed in U.S. Pat. No. 5,496,305 to Kittrell et al, and biopsy devices and drug delivery systems, such as disclosed in U.S. Pat. No. 4,900,303 and U.S. Pat. No. 4,578,061 to Lemelson.
[0022] Prior art attempts at tracking motion using cross-correlation and other simple distance measurement techniques have not been highly effective where signal intensities vary either within images, between images, or both. U.S. Pat. No. 6,292,683 to Gupta et al. discloses a method and apparatus to track motion of anatomy or medical instruments between MR images. The invention includes acquiring a time series of MR images of a region of interest, where the region of interest contains the anatomy or structure that is prone to movement, and the MR images contain signal intensity variations. The invention includes identifying a local reference region in the region of interest of a reference image and acquired from the time series. The local reference region of the reference image is compared to that of the other MR images and a translational displacement is determined between the local reference region of the reference image and of another MR image. The translational displacement has signal intensity invariance and can accurately track anatomy motion or the movement of a medical instrument during an invasive procedure. The translational displacement can be used to align the images for automatic registration, such as in myocardial perfusion imaging, MRA, fMRI, or in any other procedure in which motion tracking is advantageous. One of the problems with this invention, is that the application and implementation of this methodology has proven difficult.
[0023] Two implementations of this correction scheme have been disclosed. The first is where a correlation coefficient is calculated and used to determine the translational displacement, and one in which the images are converted to a binary image by thresholding (using signal intensity thresholds) and after computation of a filtered cross-correlation, a signal peak is located and plotted as the translational displacement. Examples of techniques using this approach are shown in U.S. Pat. No. 5,947,900 (Derbyshire) and U.S. Pat. No. 6,559,641 (Thesen)
[0024] U.S. Pat. No. 6,516,213 to Nevo discloses a method and apparatus to determine the location and orientation of an object, while the body is being scanned by magnetic resonance imaging (MRI). Nevo estimates the location and orientation of various devices (e.g., catheters, surgery instruments, biopsy needles) by measuring voltages induced by time-variable magnetic fields in a set of miniature coils, said time-variable magnetic fields being generated by the gradient coils of an MRI scanner during its normal imaging operation. However, unlike the present invention, the system disclosed by Nevo is not capable of position tracking when imaging gradients are inactive, nor is it capable of measurements outside the sensitive volume of the imaging gradients.
[0025] A subset of all of the above correction schemes is currently conventionally employed in fMRI. As in anatomical MRI, these schemes remain an incomplete solution to the problem and the search for improved motion suppression continues. Typically, fast imaging is employed to “freeze” motion within the fMRI acquisition time frame, in combination with use of head restraints to limit motion. It is still possible to achieve poor activation image quality if patients exhibit task-correlated motion on the order of 1 millimeter. This problem is particularly manifest in specific patient populations (e.g. dementia, immediate post-acute phase of stroke). Furthermore, image-based coregistration algorithms suffer from methodological limitations. Consequently, the resulting co-registered images still can suffer from residual motion contamination that impairs the ability to interpret brain activity.
[0026] Another method of tracking the position of a patient in an MRI is disclosed in US Application 2005/0054910, published Mar. 10, 2005. In this approach, a reference tool is fixed to a stationary target as close as possible to the centre of the sensitive measuring volume of an MRI-compatible camera system. There are several drawbacks of this approach, including the requirement of a second “tracking” component that must be calibrated with a dummy object, the position ambiguity due to the configuration of this approach, and the inherent limitation of the resolution provided by this approach.
[0027] U.S. Pat. No. 6,879,160 to Jakab describes a system for combining electromagnetic position and orientation tracking with magnetic resonance scanner imaging. Jakab discloses a system where the location of a magnetic field sensor relative to a reference coordinate system of the magnetic resonance scanner is determined by a tracking device using a line segment model of a magnetic field source and the signal from a magnetic field sensor. However, resolutions provided by the Jakab invention are not as precise as is possible.
[0028] There is consequently a need for improved patient movement tracking techniques in medical imaging. There is a need for improved patient movement tracking that can function in adverse environments including high strength magnetic and/or radio frequency fields without the tracking mechanism exerting it's own RF pulse or magnetic field. There is a need for improved patient movement tracking techniques that can be performed in real time. In particular, but without limitation, there is a need for real time tracking of a patient's head position in a high field strength fMRI without disrupting the scanning by the fMRI.
SUMMARY OF THE INVENTION
[0029] The present invention includes improvements to the field of tracking patient movement in an MRI application. An apparatus and method are taught to track the movement of a patient's head during medical imaging scanning using optical technology. Feedback control of the gradient and/or radiofrequency magnetic fields can provide real time correction of imaging data.
[0030] The following terms should be given the following meanings:
[0031] “Cross-correlation”—Cross-correlation is meant to include the process used to calculate the geometric translation differences between two separate and independent images. This process also compares two sequences of images on element-by-element bases and can provide the point of peak of most similarity.
[0032] “Structured light”—Structured light is meant to include patterns of light that are suitable for cross-correlation. Generally speaking this may include a bundle of light rays that may be patterned or structured in order to enhance the performance of an optical measurement. Typically, the encoding of structured light is predetermined, so that the record of optical data can be optimally processed for spatial measurements. Examples of structured light may include, but are not limited to, amplitude encoding, phase encoding, or a chromatic (or color) encoding.
[0033] “Phase correlation”—Phase correlation is meant to include the method of taking the Fourier Transform of two or more images and correlating the relative phases to find rotation or scale between them.
[0034] “Laser”—The term laser includes illumination sources of sufficient intensity to drive detector optics to get a result. The illumination sources can include broadband sources such as incandescent lamps and flashbulbs. Narrowband sources are also included such as gas discharge lasers or solid-state compound ataxia lasers. Illumination sources can also include LEDs and/or arrays of LEDs. Illumination sources can further include sources of selected wavelength ranges or groups of ranges.
[0035] One embodiment of the instant invention is a system that is taught used in conjunction within an MRI machine that uses a predetermined pattern placed or projected onto a patient's head to track movement of a patient during an MRI scan. Optical systems incorporating structured light and a processor record the position and movement of the pattern and are able to perform mathematical analysis of the pattern to determine the positional shift of the patient. Weighted averages, Fourier transforms, Hadamard matrices and cross-correlation of data related to X-Y translation, rotation and scaling of the image of the pattern are used to analyze movement of the patient's head. Feedback related to the movement is provided to the MRI machine that allows for adjustments in focusing coils for real time tracking of the patient's movements during the MRI procedure. As a result, the MRI procedure becomes more accurate as it is adjusted for the patient's movements.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] For a more complete understanding of the features and advantages of the present invention, reference is now made to the detailed description of the invention along with the accompanying figures in which corresponding numerals in the different figures refer to corresponding parts and in which:
[0037] FIG. 1 is example of pseudo Matlab code that can be used in the weighted average approach of comparing two images.
[0038] FIG. 2 is example of pseudo Matlab code that can be used in the cross correlation of two images.
[0039] FIG. 3 is illustration of the conversion between different coordinate systems.
[0040] FIG. 4 is example of pseudo Matlab code that can be used in the Fourier-Mellin approach of comparing two images.
[0041] FIG. 5 is a schematic illustration of a head tracking apparatus comprising a light source, structured light generated between the light source and the conveying light path, an object to be imaged, and a detector array.
[0042] FIG. 6 is a schematic illustration of a head tracking apparatus comprising a light source, structured light generated in the conveying light path, an object to be imaged, and a detector array.
[0043] FIG. 7 is a schematic illustration of a head tracking apparatus comprising a light source, structured light that is generated between the conveying light path and the object to be tracked, the object to be imaged, and a detector array.
[0044] FIG. 8 is a schematic illustration of a head tracking apparatus comprising a light source, a structured light generator at the object to be imaged, the object to be imaged, and a detector array.
[0045] FIG. 9 is a block diagram of a head tracking apparatus used to provide active feedback to the measurement fields of the MRI.
[0046] FIG. 10 is a flow chart illustrating a method of head tracking.
[0047] FIG. 11 is an illustration of one predetermined target that can be used to with structured light.
[0048] FIG. 12 is an illustration of a predetermined target being placed onto a patient's forehead.
[0049] FIG. 13 is an illustration of a predetermined target being projected onto a patient's forehead.
[0050] FIG. 14 is a flow chart illustrating a method of providing active feedback to the measurement fields of the MRI based on head tracking data.
[0051] FIG. 15 is a flow chart illustrating a translation detection algorithm.
[0052] FIG. 16 is a flow chart illustrating a calibration algorithm.
[0053] FIG. 17 is a flow chart illustrating one preferred embodiment of image correlation.
[0054] FIG. 18 is an illustration of a target comprised of three patterns made up of different dyes irradiated by sources of different frequencies.
DETAILED DESCRIPTION OF THE INVENTION
[0055] While the making and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts which can be embodied in a wide variety of specific contexts. The specific embodiments described herein are merely illustrative of specific ways to make and use the invention and do not delimit the scope of the invention.
[0056] In one embodiment of the instant invention is a system that is used in conjunction within an MRI machine that uses a predetermined pattern placed or projected onto a patient's head to track movement of a patient during an MRI scan. Optical systems record the position and movement of the pattern and are able to perform mathematical analysis of the pattern to determine the positional shift of the patient.
[0057] In this preferred embodiment, light is projected onto a target that reflects some of the light into an optical receiver. One of the innovations of the present inventions is the use of structured light. Structured light consists of an orderly pattern of rays of light that is suitable for cross-correlation. Examples of methods to create structured light include, but are not limited to, using of a laser to create a speckle pattern, a spatial filter using a projector to convey the structured light pattern (an example would be with use of a patterned slide), and using a light source directed towards an area with a known pattern. Other examples are an array of light emitters either positioned as a projector towards the target or as a light emitting tag placed on the target. Another example is a spatial light modulator used in the path of projected light such as a liquid crystal display or a MEMS device. Chemically patterned light emitting tags can also be used. Examples of these devices are a light emitting tag containing patterns created by phosphorescent paint, inks or dyes. Other examples include various fluorophores used in inks or dyes such as pthalacyamine and napthacyanine. In embodiments where inks and dyes are used with frequency shifting capabilities such as up converters and down converters, illuminating light should match the frequencies at which the tag produces light in detectable levels.
[0058] Since motion detection was implemented using a cross-correlation algorithm, any form of similarity within the structured light would adversely influence the robustness of the algorithm. Therefore, any regularity or order in the pattern would produce multiple peaks in the cross-correlation thus making it difficult to decide upon the highest one. This embodiment avoids the problem of similarity within the projected light source by the use of an optimized pattern of structured light.
[0059] Many algorithms and methods of signal processing can be employed by the present invention in order to determine and track movement of the structured light received either from the target or from the structured light generator. The preferred embodiment uses weighted averages, cross-correlation, Fourier-Mellin, phase correlation and image maximization to determine movement. Of course, other signal processing methods known in the art will suffice. A weighted average is one method used to calculate X and Y translational motions. The method treats every black pixel as a one and every light pixel as a zero. A pixel is considered black if its RGB value exceeds a certain preset value. In addition, a pixel is considered white if its RGB value is lower than a certain preset value. The algorithm calculates the center of the image's imaginary weight in much the same way as a center of mass would be calculated. The algorithm calculates the weighted average of the columns and rows. When the pattern translates in two-dimensional space, the weighted average stays at the same place within the pattern. This allows for the determination of the amount of translation that has occurred between the two images. One example of an implementation of this weighted average approach in a software application such as Matlab is given in FIG. 1 .
[0060] Standard cross-correlation is another method that can be used to calculate the X and Y translation differences of the images. Cross-correlation compares two sequences of images of a single target on an element-by-element basis and is able to provide the point or peak of “most similarity”. By calculating the coordinates of this peak, it is possible to find the translation between the two images. Cross-correlation of two images can be imagined as sliding one three dimensional image over another until a perfect fit it found. The cross-correlation of two complex functions f(t) and g(t) of a real variable t, denoted fHg is defined by the following equation where * denotes convolution and ƒ is the complex conjugate of f(t):
[0000] ƒ* g ≡ ƒ (− t )* g ( t ),
[0061] One example of an implementation of this cross-correlation approach in a software application such as Matlab is given in FIG. 2 .
[0062] In another embodiment, the cross-correlation of rotation is found by using a Fourier-Mellin algorithm. Fourier-Mellin method transforms Cartesian coordinates to polar coordinates and correlates the Fourier Transform of the two images to find the angle of rotation. One illustration of the difference in the coordinate systems is given by FIG. 3 . The traditional definition of the Fourier-Mellin transform is:
[0000]
f
(
t
)
=
1
2
π
i
∫
c
-
i
∞
c
+
i
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F
(
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)
e
st
s
,
t
>
0
,
[0063] The Fourier-Mellin transform is invariable in translation, rotation, and scale. The Fourier-Mellin method consists of four steps. First, the FFT (Fast Fourier Transform) of an image is taken. A FFT is a discrete Fourier transform algorithm which reduces the number of computations needed for N points from (N2) to (2*N*(lg N)), where lg is the base-2 logarithm. If the function to be transformed is not harmonically related to the sampling frequency, the response of an FFT looks like a sinc function (although the integrated power is still correct). Aliasing (leakage) can be reduced by apodization using a tapering function. However, aliasing reduction is at the expense of broadening the spectral response.
[0064] The second step of the Fourier-Mellin transform is involves the step of taking the Cartesian coordinates and converting them to Log-Polar coordinates. This allows for a correlation between translation in the Fourier-Mellin domain and rotation in Cartesian domain.
[0065] Third, the Mellin Transform is taken. The Mellin transform is an integral transform that and is generally regarded as the multiplicative version of the two-sided Laplace transform. The general equation for a Mellin transform on an equation f(t) is:
[0000]
{
Mf
}
(
s
)
=
ϕ
(
s
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=
∫
0
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x
s
f
(
x
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x
x
.
[0066] Finally, the data from the output is analyzed to determine the point of most similarity and adjustments for movement may be made. One example of an implementation of this Fourier-Mellin approach in a software application such as Matlab is given in FIG. 4 .
[0067] Another signal processing method used is Phase Correlation. Phase Correlation consists of taking the Fourier Transform of the two images and correlating the relative phases to find rotation or scale. Phase correlation is another technique that utilizes a Fast Fourier Transform or FFT.
[0068] By taking the two dimensional FFT of an image, phase information can be visualized. One equation used to acquire the FFT of an image is:
[0000]
f
j
=
∑
k
=
0
n
-
1
-
2
π
j
·
(
k
/
n
)
x
k
[0069] In two dimensions, the x k can be viewed as an n 1 ×n 2 matrix. The algorithm corresponds to first performing the FFT of all the rows and then of all the columns (or vice versa).
[0070] In the phase correlation technique, it is possible to compare the phases of the two images to detect the difference between the two images. By determining the point where the phases are at the maximum congruency, it is possible to determine the angle of rotation between two images. By analysis of the transform, the phase information that is contained in an image is acquired. The change in the phase information holds the key to determining the rotation angle of the image. The peak in the middle of the graph corresponds to the point of most congruency of the phases of the two images, and gives the change in angle that the image has undergone. The phase correlation algorithm was utilized using the following steps. First, the discrete FFT of two images is calculated. Second, the conjugate of the second image is taken. Third, the Fourier transforms are multiplied together element-wise. Fourth, the product of this multiplication is normalized element-wise. Fifth, the normalized cross power spectrum inverse transform is performed. Sixth, the peak of the inverse transform is taken. This step may include using sub-pixel methods to determine where a peak is found.
[0071] In one preferred embodiment, the results from the structured light were optimized by maximizing the percentage of the image taken up by structured light without the structured light exceeding the boundaries of the target image. This preferred upper boundary (i.e. the structured light staying within the target image) is a result of the reliance by the cross-correlation algorithms on a pixel-by-pixel comparison of two images. Since the algorithm compares structured light, it is desirable to achieve the best ratio of pixels per structured light element. If the structured light takes up 100% of the image, no change can be perceived between the structured light and the surrounding environment. If the size of the structured light is too big (90%), different translational and rotational motions might take some of the structured light out of the field of view of the camera thus contributing to loss of information contained in the structured light. On the other hand, if the structured light constitutes too little (1%) of the overall image, cross-correlation and Fourier-Mellin algorithms will not be robust enough to perform precise calculations.
[0072] In FIG. 5 , one preferred embodiment is shown. Light is generated with coherent laser 520 . The light passes through structured light generator 530 that is located between light source 520 and conveying light path 540 . Structured light generator 530 could be implemented as, but not limited to, a speckle pattern, a spatial filter, a slide, an array of light emitters, or a spatial light modulator based, for example, on a liquid crystal or a MEMS device. The structured light travels through conveying path 540 to object to be imaged 550 . Conveying path 540 could be an image preserving optical fiber, free space, or any medium which does not disrupt the transmission of the structured light. The structured light appears on object to be imaged 550 . Next the structured light is reflected onto return light path 560 which could be an image preserving optical fiber, free space, or any medium which does not disrupt the transmission of the structured light. If return light path 560 is free space, image optics have to be correctly determined using lenses, mirrors or other optical train as would be well known in the art. The light arrives at analyzer 570 , which could be a filter or polarizer before entering detector array 580 . In this embodiment, detector array 580 is implemented as a CCD camera. One exemplary part that could be used is a Digital Rebel XT made by Canon. The structured light pattern is used to detect the movement of object 550 .
[0073] FIG. 6 shows another preferred embodiment. Light is generated with coherent laser 620 . It enters conveying light path 640 . Conveying light path 640 could be a multimode fiber or any medium that does not disrupt the transmission of the structured light. Inside conveying light path 640 , a structured light pattern is generated, for example a speckle pattern. The structured light appears on object to be imaged 650 . Next the structured light goes into return light path 660 , which could be an image preserving fiber, example-coherent bundle, free space, or through any medium which does not disrupt the transmission of the structured light. If return light path 660 is free space, image optics have to be correctly determined using lenses, mirrors or other optical train as would be well known in the art. The structured light enters detector array 670 which, in this embodiment, is implemented as a CCD camera. The structured light pattern is used to detect the movement of the object 650 .
[0074] In FIG. 7 , another preferred embodiment is shown. Light is generated with coherent laser 720 . The light travels on conveying path 740 to structured light generator 730 that is located between conveying light path 740 and object to be imaged 750 . Conveying light path 740 could be an optical fiber, free space, or any medium that does not disrupt the transmission of the structured light. Structured light generator 730 could be implemented as, but not limited to, a speckle pattern, a spatial filter, a slide, an array of light emitters, or a spatial light modulator based, for example, on a liquid crystal or a MEMS device. The structured light appears on object to be imaged 750 . Next the structured light goes into return light path 760 which could be an image preserving fiber, example-coherent bundle, free space, or any medium that does not disrupt the transmission of the structured light. If return light path 760 is free space, image optics have to be correctly determined using lenses, mirrors or other optical train as would be well known in the art. The light arrives at analyzer 770 , which could be a filter or polarizer before entering detector array 780 . Detector array 780 is implemented in this embodiment as a CCD camera. The structured light pattern is used to detect the movement of object 750 .
[0075] In FIG. 8 , another preferred embodiment is shown. Light is generated with coherent laser 820 . The light travels on conveying path 840 to structured light generator 850 that is located on the object. Structured light generator 850 is a reflective material that produces structured light; an example would be a tag with a high-resolution matrix on it, or a hologram. The structured light appears on object to be imaged 860 . Next the structured light goes into return light path 870 . If return light path 870 is free space, image optics have to be correctly determined using lenses, mirrors or other optical train as would be well known in the art. The light arrives at analyzer 880 , which could be a filter or polarizer before entering detector array 890 . The filter can be responsible for selectively allowing a specified frequency of light to reach the detector. In this embodiment, detector array 890 is implemented as a CCD camera. The structured light pattern is used to detect the movement of object 860 .
[0076] In yet another preferred embodiment, structured light generator 850 is a physical target with the ability to independently produce a structured light pattern. In this embodiment, a matrix of high intensity LED devices is arranged in the pattern to transmit a structured light beam to a receiver.
[0077] In another embodiment, structured light generator 850 is a tag which has impressed on it a laser luminophore such as a polycyclic chemical compound that is usually characterized as fluorescent. Fluorophores are also suitable. Suitable laser luminophores are available as laser pumped dyes sold for example by Lambda Physik Goettingen, Germany. Typical laser luminophores display fluorescence in the range of 300 to 2500 nm and have a peak width of about 200 nm. Suitable dyes are applied to a reflective tag in a pattern which produces structured light when illuminated with radiation and wavelengths which produced fluorescence. Light sources such as laser light sources emitting in the 200 to 600 nm range are suitable. The most preferred sources include XeCl-excimer lasers (309 nm), nitrogen lasers (337 nm) and Nd:YAG (335 nm). Other preferred light sources LEDs which generally emit light in a wavelength range of about 400 to 600 nm. Chemical compounds useful as fluorophores in this embodiment include polycyclic hydrocarbons including catacondensed and pericondensed aromatics, heterocyclic hydrocarbons, including condensed and substituted indoles, oxazoles, oxadiazoles and furnin compounds and xanthono and xanthonone derivatives including condensed systems, acids and salts. Representative laser luminophores which are useful in this embodiment include p-quatraphenyl, perchlorate benzoic acid, monohydrochloride. Of course, other laser luminophores and fluorophores will also suffice. Representative laser luminophores which are useful in this embodiment include p-quatraphenyl, perchlorate benzoic acid, monohydrochloride. Of course, other laser luminophores will also suffice.
[0078] In yet another embodiment, visible dyes and invisible dyes such as laser luminophores or flurophores are used on a tag in different or similar patterns. Illuminating radiation of different frequencies can then be used to produce reflectances in structured light of different frequencies so that changes in motion of the structured light generator can be detected in two frequencies at the same time. The redundancies are available allow more accurate determination of movement of the structured light generator.
[0079] In FIG. 18 , another preferred embodiment is shown. Structured light generator 1850 in this embodiment is a physical tag having three different patterns impressed on it with dyes including a visible dye, a laser luminophore dye, and a flurophore. Each of the patterns is different. Light is generated corresponding to the first dye by light source 1805 . Reflected light from light source 1805 impinges on structured light generator 1850 and is reflected toward filter 1810 and receiver 1815 . Filter 1810 is designed to tune the light received from structured light generator 1850 to a frequency receptive to the laser luminophore dye. Light source 1820 produces light at a certain different frequency which impinges on structured light generator 1850 and is reflected toward filter 1825 and receiver 1830 . Filter 1825 is designed to tune the light from light source 1820 to the frequency of the flurophore included in structured light generator 1850 .
[0080] Light source 1830 generates light at a third frequency which impinges on structured light generator 1850 and is reflected at a certain visible frequency toward filter 1835 and receiver 1840 . Filter 1835 is designed to tune the reflected light from tag 1850 to a visible frequency. Each of the receivers is capable of registering the pattern produced by a specific dye on structured light generator 1850 .
[0081] In a block diagram of head tracking apparatus 910 providing active real time feedback to the measurement fields of MRI instrument 980 is shown. Light is generated with head tracking apparatus 910 . The structured light travels on conveying path 920 to object 930 under analysis. Next the structured light goes into return light path 940 which could be an image preserving fiber, example-coherent bundle, or free space. The structured light is registered at head tracking apparatus 910 and sent to interface 960 between MRI instrument 980 and the head tracking apparatus via information-carrying channel 950 . Interface 960 can be implemented as a computer. Interface 960 calculates the change in position of object 930 under analysis and sends the information to MRI instrument 980 via information carrying channel 970 . MRI instrument 980 adjusts the fields according to the new position information. This is accomplished in real time between successive scans of the MRI instrument.
[0082] In FIG. 10 , a flow chart illustrating the method of head tracking is shown. In the first phase structured light is generated 1010 . In the second phase, structured light is used to measure position 1020 of the object. In the third phase, the object moves and the received structured light 1030 pattern changes. In the fourth phase, the change in the received structured light pattern is calculated 1040 .
[0083] The object for the structured light to be focused on may be created in a number of ways depending on the embodiment chosen. One preferred embodiment is the use of a random monochromatic pattern that is used as a target. FIG. 11 is an example of one target that may be used to optimize the results from structured light. FIG. 12 is an illustration of the technique of placing this type of target pattern or tag onto a patient's forehead. FIG. 13 is an illustration of the technique of projecting this type of pattern onto a patient's forehead. One an exemplary part that can be used for projection is an EP 751 DLP made by Optima.
[0084] In FIG. 14 , a flow chart illustrating the method of providing active feedback to the measurement fields of the MRI based on the head tracking data is shown. In the first phase structured light is generated 1410 . In the second phase, structured light is used to measure position 1420 of the object. In the third phase, the object moves and the received structured light 1430 pattern changes. In the fourth phase, the change in the received structured light pattern is calculated 1440 . In the fifth phase, the calculated change in the position of the object is sent to MRI instrument interface 1450 . In the sixth phase, interface 1450 communicates with the MRI instrument to adjust the fields of the MRI to improve scan 1460 . This is accomplished in real time between successive scans of the MRI instrument.
[0085] FIG. 15 is a flow chart illustrating one implementation of the Translation Detection Algorithm. Structured light is projected on target 1505 . A first image is recorded (image N) 1510 . Another image is then recorded (image N+1) 1515 . Host computer cross-correlates images (images N and N+1) 1520 . The host computer finds the peak of cross-correlation that corresponds to the point of ‘most similarity’ 1525 . The host computer infers transformation data from the location of the cross-correlation peak and sends results to the MRI 1530 . The next image is recorded (image N+2) 1535 . Host computer cross-correlates images N+2 and N+1 1540 . Find the peak of cross-correlation that corresponds to the point of ‘most similarity’ 1545 . Infer transformation data from the location of the cross-correlation peak and send results to MRI 1550 .
[0086] FIG. 16 is a flowchart illustrating a possible method of calibration. Structured light is projected on target 1605 . The first step is for a first image is recorded 1610 . The next step is for a second image is recorded (image N+1) 1615 . The host computer cross-correlates acquired images 1620 . The coordinates from image N are assigned to be at a point based in Cartesian coordinate system 1625 . This point can be used as a reference point for all further image calculation.
[0087] FIG. 17 is a flowchart illustrating another method of using structured light to correct for motion data. In this embodiment, there are three separate components: a host connected to an optical receiver capable of receiving, processing, and cross-correlating images, a network computer to create a motion file based on information obtained from the host computer, and an MRI controller capable of interfacing with the network computer to accept data from the network computer and correct MRI results based upon data obtained by the network controller.
[0088] In the embodiment that is illustrated by FIG. 17 , the first step is to project a predetermined pattern of structured light onto target, where the area of the structured light is less than the area of the pattern, and where the structured light falls completely within the target 1705 . Structured light is reflected off the target and into the host optical receiver, and an image (image N) is captured by host optical receiver and time stamped 1710 . The next step is for a second image to be recorded (image N+N) and time stamped 1715 . The host computer cross-correlates images (images N and N+1) and finds the peak of cross-correlation that corresponds to the point of ‘most similarity’ 1720 . The host computer infers transformation data from the location of the cross-correlation peak and sends results to network computer 1725 . The network computer creates a motion file indicating where motion has occurred, what type of motion has occurred, and the magnitude of the motion and creates correction file 1730 . The network computer transmits the correction file to MRI controller 1735 . The MRI controller corrects the MRI results to adjust for the motion detected by the host computer by using the time stamps on each image taken by the MRI to the motion data time stamped by host computer 1740 . If the MRI scan is complete, the host turns off structured light 1760 . If the MRI scan is not complete, image M is recorded by host and time stamped 1750 . The host computer cross-correlates images (images N and M) and finds the peak of cross-correlation that corresponds to the point of ‘most similarity’ 1755 . The host computer infers transformation data from the location of the cross-correlation peak from the original image N and the new image M and sends results to network computer 1725 .
[0089] It is envisioned that the embodiment illustrated by FIG. 17 could be modified to allow for the three components (e.g. network computer, host computer, and MRI controller) to be integrated into one or more components. It is further envisioned that one computer to accomplish one or more of the tasks, i.e. a central computer both capture and process images and transmit the data directly to an MRI. It is further envisioned by the inventors that the comparison in images could be made from the each previous image in the sequence rather than from the first image to give a clearer view of subtle changes in movement.
[0090] It is further envisioned that there are other methods to use structured light patterns; i.e. electronic detection patterns such as sensors attached to the patient's head that could be used as an alternative to optical receivers. Moreover, any number of different types of light source may be used to project light, including, but not limited to, strobe lights. It is further envisioned that in some embodiments target itself emanate light by the use of a target that emits light directly into an optical receiver.
[0091] While this invention has been described in reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments, as well as other embodiments of the invention, will be apparent to persons skilled in the art upon reference to the description. It is therefore intended that the appended claims encompass any such modifications or embodiments.
[0092] As will be recognized by those skilled in the art, the innovative concepts described in the present application can be modified and varied over a tremendous range of applications, and accordingly the scope of patented subject matter is not limited by any of the specific exemplary teachings given. | The present invention discloses a method for determining location and movement of a moving object. One embodiment of the method tracks the movement of a target during medical imaging scanning and transmits the position shift to the medical imaging scanning device in real time. The method includes the steps of projecting structured light on the target, receiving the reflection of structured light, converting the received structured light into spatial positions, and transmitting the positional shift to the medical imaging scanning device. The method further includes the step of adjusting the medical imaging scanning device in response to the positional change to increase accuracy. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit of U.S. provisional application serial No. 60/243,526, filed on Oct. 26, 2000, the teachings of which are incorporated herein by reference.
FIELD OF INVENTION
[0002] This invention relates to ultra-high vacuum systems, specifically to a system for the insertion of components between two standard thickness flanges.
BACKGROUND OF THE INVENTION
[0003] Vacuum systems find wide applications in research, education, product development, and production. Typical systems comprise independent and interchangeable components. Such components may include testing chambers, pumps, gauges, valves, specimen holders, testing apparatus, heating systems, and cooling systems.
[0004] Processes or experiments that require high or ultra-high vacuum (UHV) currently employ all metal vacuum joints. A typical all-metal joint, such as that disclosed in U.S. Pat. No. 3,208,758, is illustrated in FIG. 1. Such a joint comprises a flange 20 , illustrated in FIG. 2, that includes an annular recess 26 and an annular knife edge 30 . The flange 20 is configured for mating with another like flange 24 separated by a soft, metallic gasket 34 . The opposing knife edges 30 , 32 are pressed into the gasket 34 by tightening bolts 38 forming the UHV seal.
[0005] The force of the equally spaced bolts is transferred to the gasket through the thickness of the flange. The bolt holes are disposed on a diameter that is outside that of the knife edge. If the standard gasket is not of appropriate thickness, the flange will deform in the shape depicted in FIGS. 3 and 4 between opposing bolts 38 . The bowing of the flange occurs due to the moment arm between the knife edge 30 , 32 and the bolt 38 . This may also create a wave-like deflection between the adjacent bolt holes. This shape is depicted in FIGS. 3 and 4. In the case of such a deflection or deformation, the gasket may leak if the force placed on the gasket between the adjacent bolts is less than the force required to press the knife edges sufficiently into the gasket to form a seal. Only an appropriate thickness of the flange provides resistance to bending deformation.
[0006] In UHV systems, the level of vacuum attainable is dependant upon the speed of the vacuum pumps, the leak rates of the vacuum joints and vacuum walls, the surface area of the chamber and pumping lines, and the surface roughness of the interior components. Cleanliness or purity of the vacuum environment depends upon the interior component's material, forming method, and surface finish. Additionally, the practicality of a vacuum system depends on the ease of access for changing specimens, the required downtime to troubleshoot and to make repairs, and the ease with which components can be added and removed from the system. The expense of a vacuum system lies in the cost of components, the required pump types and speeds, as well as the number and type of extra adapters needed to attach components to the system. Methods of accurately placing testing apparatus, processing equipment, or samples within a system are often required for an experiment or process. The prior art flanges, such as the one discussed above, do not completely optimize some of these requirements in some cases.
[0007] Methods for inserting or mounting apparatus in a vacuum system currently involve one of several options, all of which significantly increase size and/or complexity of the vacuum system. Typical apparatus mounting methods include inserting two thick flanges on each end of an extruded or welded tube, such as that illustrated in FIG. 5, where the tube or the flanges provide the mounting structure. Alternately, double-sided couplers, such as that shown in FIG. 5A, which bolt to the chamber and bolt to the apparatus may be employed. Couplers of this type not only add significant length and surface area, but also introduce inaccuracies to the system. Adding length and surface area decreases conductance (the ease at which gas can flow through the system) and increases the likelihood of contaminants in the system. With decreased conductance, a system will need larger, more expensive pumps in order to achieve the same vacuum level. The welded flanges have inherently poor parallelism that can cause problems if accurate placement of a component is required. While an existing system, or part of a system, can be modified to provide a mounting structure, that system, however, may be too large and cumbersome to be easily modified.
[0008] A large component, such as a pump, often cannot be mounted horizontally, or “cantilever style,” from a welded flange coupler without the aid of auxiliary support due to the weakness of the thin walled extension tube. Thin walled extension tubes also cannot accommodate internal mounting systems that require mounting grooves, such as those described in Crawford, U.S. Pat. No. 5,593,123, the teachings of which are incorporated herein by reference, in the extension tube wall.
[0009] The prior art for providing feed-through from the exterior atmosphere into a vacuum chamber is generally a single flange or welded feed-through. Both of these approaches require the testing apparatus to be independently mounted within the vacuum chamber and the feedthrough to be mounted on a chamber port. Under these circumstances, attachments, such as electrical wiring, must be done and redone whenever the apparatus is removed from the system. Having to needlessly redo complicated connections causes increased system downtime for repairs or component changes, and also leads to possible errors when re-connections are made.
[0010] The prior art valves between a vacuum chamber and another component are another source that can significantly decrease the vacuum system's conductance, and also require significant space. Generally, a valve is attached to a vacuum system using a coupler, such as that described previously, having a tapped through-hole. Therefore, anytime a valve is added to the vacuum system, a bulky coupler must be added, reducing the system's conductance.
SUMMARY OF THE INVENTION
[0011] A system for the insertion of components between two standard thickness flanges of a vacuum system. The system herein comprises a thin flange configured to be disposed between and seal against two standard flanges of vacuum system components. The thin flange comprises sealing surfaces on opposed sides of the flange, such that a vacuum tight seal may be achieved when the thin flange is compressed between the two standard thickness flanges, wherein the thin flange experiences only symmetrical forces. The sealing surfaces of the thin flange may each comprise a knife edge disposed within the perimeter of the thin flange, whereby the knife edge may at least partially penetrate into a metal gasket when the thin flange is clamped between two standard thickness flanges. Advantageously, the thin flange may be equipped with one or more feed-throughs, openings, and/or mounting features for retaining apparatus in or around the vacuum system. The symmetry of the forces applied to the thin flange assure that the flange will not experience any bending, deflection, or distortion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Exemplary embodiments of the invention are set forth in the following description and shown in the drawings, wherein:
[0013] [0013]FIG. 1 is a perspective view of a prior art all metal joint;
[0014] [0014]FIG. 2 illustrates a prior art seal in cross-sectional view;
[0015] [0015]FIG. 3 shows a distorted prior art flange in cross-sectional view;
[0016] [0016]FIG. 4 is a perspective view of a distorted gasket from a prior art all metal seal;
[0017] [0017]FIGS. 5 and 5A illustrate in perspective view prior art coupling members;
[0018] [0018]FIG. 6 is a perspective view of a thin flange consistent with the present invention;
[0019] [0019]FIG. 7 is a sectional view of the exemplary thin flange consistent with the present invention illustrated in FIG. 8A taken along cutting line A-A;
[0020] [0020]FIGS. 8 through 8B illustrate an exemplary embodiment of the thin flange consistent with the present invention;
[0021] [0021]FIG. 9 is a perspective view of an alternate exemplary thin flange consistent with the present invention;
[0022] [0022]FIG. 10 is a third illustrated exemplary embodiment of the thin flange consistent with the present invention shown in perspective view.
DETAILED DESCRIPTION OF THE INVENTION
[0023] Referring to FIGS. 6 through 10, various exemplary embodiments of double-sided “thin flanges” consistent with the present invention are illustrated. It should be understood that the term “thin flange”, as used herein, is not so much an absolute dimensional characterization as it is a convenient designation, indicating that the flange is not required to be thick enough to withstand the stress and deflection imposed by the clamping bolts. The thickness of the flange is rather determined primarily by the thickness required to provide the instantly desired mounting characteristics or features—i.e., mounting grooves, threaded bores, feed-throughs, etc., as discussed in the following description of the invention.
[0024] [0024]FIGS. 6 through 8B show details of a first exemplary embodiment of a thin flange 40 having a sealing surface 42 to crush a pair of metallic gaskets 44 A, 44 B for forming an all-metal joint. A plurality of bolt holes 46 are located outside of the perimeter of the sealing surfaces 42 and 50 to provide a method of securing the thin flange 40 to another component 48 with a compatible sealing surface 50 before tightening the bolts 45 . The bolt holes 46 provide alignment of the flange 40 relative to the other component 48 prior to sealing. However, once the seal is formed by tightening the bolts 45 and crushing the gaskets 44 A and 44 B, no support is provided to the flange by the bolts 45 . The thickness of the thin flange 40 is optimized to provide adequate strength while maintaining a minimum thickness.
[0025] [0025]FIG. 7 is sectional view of the exemplary thin flange 40 taken along cutting line A-A referred to in FIG. 8A. This cross section shows the details of the sealing surfaces 42 and 50 including knife edges. Consistent with the present invention, internal vacuum components may be mounted using equipment-mounting grooves 52 . These specific equipment mounting grooves 52 permit the mounting of internal vacuum system components (not shown) as described in Crawford U.S. Pat. No. 5,593,123. As illustrated, the equipment-mounting grooves 52 are disposed in a region of the thin flange 40 located within the perimeter of the mounting surfaces 42 and 50 . Accordingly, components may be mounted extending out of the plane of the thin flange 40 . Consistent with this configuration, components may be mounted to the vacuum system over a much shorter distance than previously possible because the thin flange 40 eliminates the need for a tube or double-sided coupler or an independent structurally thick double-sided flange. Not only does the decrease in length required to mount components make the system more convenient in space-limited applications, it also increases the conductance of the vacuum system.
[0026] Referring to FIG. 8, there is shown an exemplary thin flange 40 mounted between two standard thickness flanges 48 and 54 . The two standard thickness flanges 48 and 50 are sealed against respective sides of the thin flange 40 by crush gaskets 44 A and 44 B. When the system is sealed by tightening the bolts 45 , the force exerted on the standard thickness flanges 48 and 54 by the mounting bolts 45 is effectively transferred by the rigid body of the standard thickness flanges 48 and 54 to their respective sealing surfaces and knife edges which crush both metallic gaskets 44 A and 44 B. This, in turn, causes the crushed gaskets 44 A and 44 B to bear symmetrically against the inner web 56 , which is best identified in FIG. 6. Accordingly, the thin flange 40 experiences only symmetrical compressive loading about its thickness. The bolt holes 46 of the thin flange 40 are under zero load. Furthermore, the thin flange 40 is not subject to any bending loads, as may be the case with the standard thickness flanges 48 and 54 . This allows the thin flange 40 to be of a minimal thickness, only sufficient to resist the compressive forces and contain the knife edge sealing feature. Accordingly, the inserted member could be a membrane, window, or small aperture.
[0027] Turning to FIG. 9, there is illustrated a second exemplary thin flange 64 . The second exemplary thin flange 64 is configured without bolt holes. The thin flange, according to this embodiment, allows for arbitrary radial alignment to the mating system. The greater flexibility in radial alignment of the thin flange 64 is capable because placement of the thin flange 64 relative to the standard thickness flanges (not shown) is not restricted by the need to align bolt holes in the thin flange 64 with the bolt holes in the standard thickness flanges. The thin flange 64 consistent with this exemplary embodiment is especially beneficial when an instrument or apparatus mounted to the thin flange must be precisely aligned either within the vacuum system, or relative to another instrument or apparatus.
[0028] [0028]FIG. 10 illustrates in isometric view a third exemplary embodiment of a thin flange 60 consistent with the present invention. According to the third alternate embodiment, the thin flange 60 comprises a series of mounting holes 62 disposed about the inner web 56 , inside the perimeter of the mounting surfaces of the flange 60 . The mounting holes 62 may advantageously be configured to mount any variety of apparatus inside of the vacuum system. Accordingly, the mounting holes 62 may be arranged in a pattern that is generic to a variety of equipment, or the mounting holes 62 may be specially configured for individual pieces of apparatus. By employing a thin flange 60 as disclosed herein it is possible to align vacuum components and mating interior system components with a high level of dimensional precision.
[0029] In each of the above-described embodiments, the thin flange preferably is formed from a single unitary member. By machining the thin flange, including both of the sealing surfaces, from a single member it is possible to achieve very high tolerances. Additionally, it is possible to achieve a superior surface finish on the thin flange. This characteristic lends itself to higher conductance and greater cleanliness of the vacuum system, as well as accurate flange face parallelism.
[0030] Consistent with the above teachings, a thin flange of the present invention may be beneficially employed for mounting equipment within the vacuum system itself, as well as for an interface connecting items within the vacuum system to the exterior of the vacuum system. An exemplary application may be to conveniently provide an electrical feed-through for powering an apparatus inside the vacuum system while still maintaining the “vacuum tight” integrity of the system. Similarly, the inner web of the thin flange may be equipped with a valve, therein providing direct communication with interior of the vacuum system without decreasing the conductance of the system, which does result from typical valve mounting systems disposed on a couple or tube.
[0031] Further consistent with the exemplary embodiments illustrated in FIGS. 7 and 10, and discussed with reference thereto, the thin flange can mount an interior component, such as an electron gun, as well as provide an electrical feed-through. This is an improvement over having the electrical connections on a separate port of the vacuum chamber, as is conventionally the case. The advantage is that the connection does not need to be done at the location of the vacuum system since the component can be mounted within the thin flange and the electrical connections may be made as an independent subsystem. Should the component need to be removed from the vacuum system, the connection would not need to be disassembled and subsequently reassembled when the component was remounted. This saves time, and may reduce the number of ports required on a vacuum system's main chamber.
[0032] Further embodiments of the coupling flange obviously include different lengths, different industry standard flange sizes, different flange geometries, such as oval, rectangular, or other planar shape, and different interior mounting arrangements. On slightly thicker versions of the flange, radial ports may be added to increase access to internal components. Along the same lines, tees and crosses of various sizes can be envisioned. The thin flanges could also be stacked, with the limit only being the twist up and stretch of the set of bolts.
[0033] In consideration of the various above-described embodiments and applications consistent with the present invention, it will be readily appreciated that the thin flanges consistent with the present invention may advantageously be employed in a stacked manner. Consistent with this, a plurality of thin flanges may be disposed between two standard thickness flanges, thereby providing a variety of mounting features, feed-throughs, valves, etc., while requiring only one port on the vacuum system. Because each of the thin flanges consistent with the present invention contain two sealing surfaces, any number of thin flanges may be coaxially disposed, with each pair having a soft metallic gasket disposed therebetween. Furthermore, as in the case of a single thin flange disposed between two standard thickness flanges, each of the thin flanges in the above described “stack” will experience only symmetrical forces, generally only compressive in nature, and therefore will not be subject to distortion or deflection resulting from the clamping bolts. The exact number of thin flanges which may be stacked together is limited only the length of the clamping bolts employed with the standard thickness flanges.
[0034] Accordingly, it will be appreciated that the exemplary embodiments described and depicted in the accompanying drawings herein are for illustrative purposes only, and should not be interpreted as a limitation. It is obvious that many other embodiments, which will be readily apparent to those skilled in the art, may be made without departing materially from the spirit and scope of the invention as defined in the appended claims. | A system for coupling ultra-high vacuum components specifically where a component is inserted between two standard thickness flanges. This system will minimize the length that is added onto a vacuum system when a component is added. The invention is a relatively thin flange including two sealing surfaces separated by a thin web. The thin flange of the present invention may be configured to mount a variety of equipment within a vacuum system, and/or provide connection between the interior of the vacuum system and the outside environment, such as electrical connection or fluid connection. | 5 |
CROSS-REFERENCED RELATED APPLICATIONS
This application is a continuation of International Patent Application No. PCT/CH2007/000397 filed Aug. 14, 2007, which claims priority to German Patent Application No. DE 10 2006 038 123.8 filed Aug. 14, 2006, German Patent Application No. DE 20 2006 019 890.3 filed Aug. 14, 2006, German Patent Application No. DE 10 2006 057 578.4 filed Dec. 6, 2006, German Patent Application No. DE 20 2006 019 370.7 filed Dec. 22, 2006 and German Patent Application No. DE 10 2007 001 432.7 filed Jan. 9, 2007, the entire content of all of which is incorporated herein by reference.
BACKGROUND
The present invention relates to devices for delivering, injecting, infusing, dispensing or administering a substance, and to methods of making and using such devices. More particularly, it relates to devices, structures and/or mechanisms for setting, controlling or selecting an amount or dose of a substance to be injected or dispensed from such devices. More particularly, it relates to a lock element for locking a dose setting mechanism of an injection device, e.g. an injection device for use with a two-chamber ampoule in which two substances are contained separately from one another and are mixed prior to administering by the injection device.
If a two-chamber ampoule is incompletely or only partially screwed into an injection device, there is a possibility that the substances contained in the two-chamber ampoule will not be mixed or will be only partially mixed, in which case unmixed substances or an incompletely mixed substance could be dispensed during an injection operation.
SUMMARY
One object of the present invention is to provide an element for injection devices, by which the use of injection devices can be made more reliable, including in conjunction with two-chamber ampoules.
In one embodiment, a lock element in accordance with the present invention is used to lock a setting, priming or dose setting mechanism or a setting, priming or dose setting element of an injection device, e.g. a disposable injector or an injection pen.
In one embodiment, the present invention comprises a lock for a dosing mechanism of an injection device, the lock including at least one holding element that interacts with the dosing mechanism, or with a dosing element of the dosing mechanism, whereby an adjustment movement of the dosing mechanism or the dosing element is prevented in a starting position of the lock and is possible only after a movement or displacement of the lock or the holding element. An injection device used in conjunction with a two-chamber ampoule is encompassed, as is a method for preparing the injection device for dispensing a substance wherein the ampoule is introduced into the injection device and a lock is released when the ampoule has been introduced far enough to appropriately mix the substances in the two chambers, whereupon the mixed substances can be dispensed from the ampoule.
In one embodiment, the invention comprises a blocking element for a dosing mechanism of an injection device with at least one holding element that can interact with the dosing mechanism, or with a dosing element of the dosing mechanism, in such a way that an adjustment movement of the dosing mechanism or of the dosing element can be prevented in a starting position of the blocking element and is permitted only after a movement or displacement of the blocking element or of the holding element. The invention also relates to a method for preparing an injection device for dispensing a substance from an ampoule or two-chamber ampoule, wherein the ampoule or two-chamber ampoule is introduced, e.g. screwed, into the injection device, and the blocking or anti-rotational locking of the dosing or adjusting element or a lifting element of the injection device is only released when the ampoule has been introduced so far into the injection device that a substance can be dispensed from the ampoule in a defined or dosed manner, and/or that the substances contained in the two-chamber ampoule are appropriately or properly, e.g. completely, mixed.
In one embodiment, the lock element has at least one displaceable, e.g. flexible, retaining element, which is able to co-operate with the dose setting mechanism or dose setting element of the injection device so that a priming, dose setting, or setting movement or operation can be prevented and/or precluded. In some embodiments, the movement or operation, such as a rotating or sliding movement or an extraction movement of the dose setting element is prevented when the lock element is in an initial position due to a catch connection to the lock element, and is not triggered or initiated until the at least one retaining element has been displaced or moved, for example by a sliding movement of the lock element caused by or after introducing an ampoule.
In some embodiments, a lock element in accordance with the present invention prevents a dose setting mechanism and/or a setting or dose setting element from being operated to set a dose or prime an injection device before an ampoule is loaded in the injection device. In some embodiments, the ampoule may be a two-chamber ampoule which makes contact with the lock element, and it and/or the lock element has been pushed into or moved relative to the injection device by a pre-defined distance, e.g. 2 mm, thereby releasing the dose setting mechanism, for example by moving a retaining element engaging the dose setting mechanism.
In some embodiments, the lock element is in the form of a ring and has a contact surface for contacting an ampoule or ampoule sleeve, so that an ampoule fully or almost fully inserted or screwed into the injection device moves into contact with the lock element and drives or moves it relative to the injection device or relative to the setting mechanism on the last part of the distance of the pushing-in or screwing-in movement. In some embodiments, the at least one retaining element is biased radially inwardly or radially outwardly, and locates or is receiveable in a recess or groove of a dose setting element or a dose setting device to prevent a rotating movement or extraction of the dose setting element, e.g. the lock element is fitted in or with the injection device to afford an anti-rotation lock. In some embodiments, two or more retaining elements are provided, for example two retaining elements opposite one another on an annular lock element, which can be biased radially inwardly and locate in, lodge in or be connected to the dose setting mechanism or a dose setting element in an initial position when the ampoule has not yet been fully inserted, and/or are not pushed radially outwardly to release the dose setting element or dose setting mechanism until an ampoule has been introduced.
Another aspect of the present invention relates to a dose setting mechanism for an injection device, wherein the does setting mechanism has a lock element of the type described above and at least one dose setting element, e.g. a rotating knob or a rotating sleeve. In some preferred embodiments, the dose setting element has at least one retaining or locating element or a recess, such as a groove, with which the at least one retaining element of the lock element co-operates, i.e. in which it locates. The lock element is mounted so that it is able to slide, e.g. axially, relative to the dose setting element toward, through or out of it. The at least one retaining element of the lock element may be such that during or after a sliding movement of the lock element relative to the dose setting element, the retaining element or elements is or are moved or pushed by a ramp or inclined surface that does not slide with the lock element so that a coupling no longer exists between the lock element and the dose setting mechanism or dose setting element, which means that the dose setting element or dose setting mechanism can be operated and rotated or pulled out of the injection device to set a dose or prime the injection device.
The expression “retaining element” as used herein is intended to encompass and/or mean any element, feature, structure or the like, e.g. a recess or bore, that enables a coupling or connection, e.g., an anti-rotation lock, with another element. For example, a displaceable or flexible retaining element biased radially inwardly or outwardly may be provided on the lock element and/or on the dose setting element or dose setting mechanism, which co-operates with another retaining element or a cut-out or a recess or groove on the respective co-operating element, for example the dose setting element or dose setting mechanism or lock element, to establish a releasable coupling between the lock element and the dose setting element or dose setting mechanism. In some preferred embodiments, this coupling is then released when an ampoule is or has been introduced into the injection device to a pre-defined length, e.g. by a sliding movement of at least one retaining element caused by the ampoule being introduced and guided by a guide profile.
In some embodiments, the present invention relates to an injection device with a dose setting mechanism of the type described above and an ampoule insertion part such as an ampoule sleeve or, alternatively, an ampoule body, able to co-operate with the lock element, the dose setting element or dose setting mechanism as it is inserted. This is accomplished, for example, by moving into contact with the lock element or dose setting mechanism and causes the dose setting mechanism or dose setting element to be released during the movement or sliding action of the dose setting mechanism or lock element relative to the injection device or to a housing of the injection device caused by the movement of the ampoule as it is being inserted. In this respect, the lock element may also be part of the dose setting mechanism.
In some preferred embodiments, the injection device has a guide element, such as a ramp or a profile, extending at an angle with respect to the axial direction. The guide element is disposed relative to a retaining element of the lock element or dose setting mechanism so that an axial sliding movement of the lock element or dose setting mechanism relative to the injection device causes at least one retaining element to be moved by the guide, such that the engagement between the lock element and the dose setting element or dose setting mechanism is released.
In some preferred embodiments, a flange is provided on the injection device. The flange pushes against a stopper of the ampoule, e.g. a two-chamber ampoule, when it is introduced or screwed in. This causes the stopper to be pushed into the ampoule as the ampoule is being screwed into the injection device so that the substances contained in the two-chamber ampoule are mixed.
Another embodiment of the present invention relates to a method of preparing an injection device for dispensing a substance from a two-chamber ampoule, wherein the two-chamber ampoule is introduced into the injection device, e.g. screwed in, and a lock of a setting element or priming element of the injection device is released when the ampoule has been introduced far enough into the injection device that the substances contained in the two-chamber ampoule have been properly mixed. In some embodiments, the lock is an anti-rotation lock.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view illustrating one embodiment of the present invention, a dose setting mechanism with a released lock element;
FIG. 2 is a side view of the dose setting mechanism illustrated in FIG. 1 prior to mixing;
FIG. 2A is a sectional view along line C-C in FIG. 1 ;
FIG. 2B is a detail D from FIG. 2A ;
FIG. 3 shows the dose setting mechanism illustrated in FIG. 2 once the two-chamber ampoule has been fully screwed in and mixed;
FIG. 3A is a sectional view along line A-A in FIG. 3 ;
FIG. 3B illustrates detail B from FIG. 3A ;
FIG. 4 is a plan view of an embodiment of an injection device in accordance with the present invention with the mechanism locked;
FIG. 4A is a sectional view along line A-A in FIG. 4 ;
FIG. 5 shows the injection device illustrated in FIG. 4 with the mechanism released; and
FIG. 5A is a sectional view along line B-B in FIG. 5 .
DETAILED DESCRIPTION
With regard to fastening, mounting, attaching or connecting components of the present invention, unless specifically described as otherwise, conventional mechanical fasteners and methods may be used. Other appropriate fastening or attachment methods include adhesives, welding and soldering, the latter particularly with regard to the electrical system of the invention, if any. In embodiments with electrical features or components, suitable electrical components and circuitry, wires, wireless components, chips, boards, microprocessors, inputs, outputs, displays, control components, etc. may be used. Generally, unless otherwise indicated, the materials for making the invention and/or its components may be selected from appropriate materials such as metal, metallic alloys, ceramics, plastics, etc.
FIG. 1 is a perspective view illustrating one embodiment of a dose setting mechanism in accordance with the present invention which can be inserted in an injection device. A lock sleeve disposed at least in the front or distal part inside the housing of the injection device when the dose setting mechanism is inserted has an orifice 8 a in which a retaining element 1 a of the locking ring 1 , which is biased radially inwardly and serves as the lock element, locates once the ampoule 5 has been screwed in.
In the initial position illustrated in FIG. 2 , the locking ring 1 is mounted so that it can not rotate relative to the injection device or the housing of the injection device by an orifice in the housing, in which an element of the locking ring 1 such as a retaining element 1 a is received. Thus, the dose setting sleeve 2 is mounted in the injection device so that it can not rotate due to the retaining element 1 a locating in the orifice or groove 2 a of the dose setting sleeve 2 . The locking ring 1 is biased in the distal (or forward) direction of the injection device by a spring force, for example.
FIG. 2 is a side view showing the dose setting mechanism illustrated in FIG. 1 , with the retaining element 1 a of the locking ring 1 lying relative to the groove 8 a of the sleeve 8 so that there is still a distance d to the proximal end of the groove 8 a shown on the right-hand side of FIG. 2 .
FIG. 2A is a view in section along line C-C indicated in FIG. 2 , showing how the retaining element 1 a , biased radially inwardly, is received in a groove 2 a of the dose setting sleeve 2 and thus blocks any rotating movement of the dose setting sleeve 2 relative to the housing 3 of the injection device. When an ampoule 5 inserted in an ampoule sleeve 4 is screwed into the injection device to push the rear or proximal stopper 5 a of the ampoule into the two-chamber ampoule 5 by the flange 6 mounted on the threaded rod 7 of the injection device to enable mixing in the two-chamber ampoule 5 . The proximal end of the ampoule sleeve 4 illustrated on the right-hand side of FIG. 2A moves into contact with the front face 1 b of the locking ring 1 when the ampoule sleeve 4 with the ampoule 5 in it has been screwed far enough into the injection device for the flange 6 to have been pushed sufficiently far into the ampoule 5 to have caused complete or almost complete mixing of the two-chamber ampoule. When the ampoule sleeve 4 is screwed farther into the injection device, the locking ring 1 is pushed to the right in FIG. 2A , in other words in the proximal direction, due to the contact of the proximal end of the ampoule sleeve 4 with the contact face lb. This causes the guide profile 1 c provided in the locking ring 1 to move into contact with the ramp 3 a which is not able to slide relative to the injection device. The sliding movement of the locking ring 1 causes the retaining element 1 a to be pushed outwardly against the inwardly directed biasing force of the retaining element 1 a , as illustrated in detail B of FIG. 3B , thereby releasing the retaining element 1 a from its position located in the groove 2 a of the dose setting sleeve 2 so that the dose setting sleeve 2 is no longer prevented from rotating relative to the injection device.
FIGS. 3 and 3A illustrate the status of the dose setting mechanism after the locking ring 1 has moved slightly in the proximal direction by the distance d to unlock the dose setting sleeve 2 .
After the ampoule 5 has been fully mixed and the anti-rotation lock 1 a , 2 a of the dose setting sleeve 2 has been released, the dose setting sleeve 2 can be rotated by a user to set a dose or prime the injection device, so that a dose is dispensed from the ampoule 5 during an injection.
The setting mechanism is therefore mechanically locked by the two fork-shaped lock pawls 1 a of the locking ring, which extend through co-operating recesses 2 a of the rotating or dose setting sleeve 2 . Since the pen is primed by rotating the rotating ring 2 , this is now not possible because the rotation is prevented by the locking ring 1 .
To unlock the mechanism, the ampoule sleeve 4 , which was screwed into the dose setting or setting mechanism to mix the two-chamber ampoule 5 , is screwed in. On the last approximately 2 mm of the screwing-in movement, the locking ring 1 is moved from the locked position into the unlocked position by the ampoule sleeve 4 . To this end, the locking ring 1 has inclined surfaces on the inner faces of the two fork-shaped lock pawls 1 a which complement the inclined surfaces 3 a of the guide sleeve or housing. As a result, the two lock pawls 1 a are pushed out and thus release the dose setting sleeve 2 or mechanism.
The retaining element 1 a or locking ring 1 is designed so that it is pushed in the proximal direction by the ampoule sleeve 4 , which is screwed into the pen when the ampoule 5 is screwed in to mix the substance. A ramp or slide surface 3 a , provided on the housing of the injection device, causes the retaining element 1 a of the locking ring 1 , which is moved relative to the ramp 3 a by the ampoule sleeve 4 , to be pushed radially outwardly and thus release the anti-rotation lock of the dose setting sleeve 2 . Consequently, once the ampoule sleeve 4 has been fully pushed in, a dose can be set by rotating the dose setting sleeve 2 . This ensures that the dose setting sleeve 2 can not be rotated until the ampoule sleeve 4 has been fully screwed into the pen, in other words far enough for the ampoule sleeve 4 to hit the locking ring 1 and push it by a farther distance into the injection device.
FIG. 4 is a plan view showing an injection device with the mechanism locked, as illustrated along section A-A indicated in FIG. 4A . As may be seen from FIG. 4A , the retaining element 1 a , which need not necessarily be mounted on a locking ring, is urged radially inwardly and locates or lodges in a groove 2 a of the dose setting sleeve 2 , thus blocking or locking any rotating movement of the dose setting sleeve 2 relative to the housing 3 of the injection device. The ampoule 5 inserted in the ampoule sleeve 4 can be screwed into the injection device, as illustrated in FIGS. 5 and 5A . As a result, the guide profile 1 c moves into contact with the ramp 3 a , which is not able to move relative to the injection device and is pushed outwardly against the biasing action of the retaining element 1 a due to the movement of the retaining element 1 a , once the proximal end of the ampoule sleeve 4 has reached the contact surface 1 b as may be seen from FIG. 5A . As a result, the engagement of the retaining element 1 a in the groove 2 a of the dose setting sleeve 2 is released so that the dose setting sleeve 2 is no longer prevented from rotating relative to the injection device. In the case of the injection device illustrated in FIG. 5A , the ampoule has therefore been completely or almost completely inserted and a dose setting or setting movement can take place because the dose setting sleeve 2 has been released by outward movement of the retaining element 1 a.
Embodiments of the present invention, including preferred embodiments, have been presented for the purpose of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms and steps disclosed. The embodiments were chosen and described to provide the best illustration of the principles of the invention and the practical application thereof, and to enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth they are fairly, legally, and equitably entitled. | A lock for a dosing mechanism of an injection device, the lock including at least one holding element that interacts with the dosing mechanism, or with a dosing element of the dosing mechanism, whereby an adjustment movement of the dosing mechanism or the dosing element is prevented in a starting position of the lock and is possible only after a movement or displacement of the lock or the holding element. An injection device used in conjunction with a two-chamber ampoule is encompassed, as is a method for preparing the injection device for dispensing a substance wherein the ampoule is introduced into the injection device and a lock is released when the ampoule has been introduced far enough to appropriately mix the substances in the two chambers, whereupon the mixed substances can be dispensed from the ampoule. | 0 |
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