JP4175297B2 - Gas adsorbent evaluation equipment - Google Patents

Description

  The present invention relates to a gas adsorbent evaluation apparatus, and more particularly to an evaluation apparatus suitable for evaluating the adsorption distribution of gas adsorbed by a gas adsorbent such as a filter with activated carbon.

  Conventionally, for example, Japanese Patent Laid-Open No. 6-93932 discloses an internal combustion engine that controls the amount of evaporated fuel supplied to the intake passage based on the amount of evaporated fuel adsorbed by a canister (filter with activated carbon) included in the internal combustion engine. An evaporative fuel control device for an engine is disclosed. In this apparatus, the adsorption amount adsorbed by the canister is calculated from the temperature difference between the peripheral portion and the inside of the canister.

JP-A-6-93932 JP-A-5-231209 Japanese Patent Laid-Open No. 5-248312 Japanese Patent Laid-Open No. 10-261682

  By the way, in an internal combustion engine, in order to prevent the evaporated fuel from leaking from the intake port into the atmosphere when the engine is stopped, for example, a configuration including a gas adsorbing material that adsorbs the evaporated fuel in the air cleaner of the intake passage is known. Yes. In a vehicle on which an internal combustion engine having such a configuration is mounted, the shape of the intake port of the internal combustion engine, the mounting position of the gas adsorbent, and the like are generally different for each vehicle type. Therefore, the adsorption amount distribution of the evaporated fuel (THC) adsorbed on the gas adsorbent varies depending on the vehicle type. In such a case, if the adsorption amount distribution of the evaporated fuel adsorbed on the gas adsorbent can be grasped, it is convenient for improving the adsorption efficiency of the gas adsorbent.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a gas adsorbent evaluation apparatus that can acquire the adsorption amount distribution of the gas adsorbed by the gas adsorbent. To do.

In order to achieve the above object, the first invention provides a carrier gas supply means for supplying a carrier gas for desorbing the measurement target gas to the gas adsorbent,
A first adsorbent holder that has a first opening that covers a part of the filtration area of the gas adsorbent, is installed downstream of the carrier gas supply means, and into which the carrier gas is introduced;
A second opening formed with substantially the same size as the first opening, and the second opening is arranged to face the first opening through the gas adsorbent; A second adsorbent holder,
Holder holding means for holding the first adsorbent holder and the second adsorbent holder pressed against the gas adsorbent;
Measuring part changing means for changing the measuring part of the gas adsorbent by displacing the first adsorbent holder and the second adsorbent holder;
A gas mass acquisition means installed on the downstream side of the second adsorbent holder for acquiring the mass of the measurement target gas desorbed from the measurement site;
A mass distribution display means for displaying a distribution of the mass for each of the measurement sites acquired by the gas mass acquisition means;
It is characterized by providing.

In a second aspect based on the first aspect, the holder holding means is a pair of magnetic poles arranged at different edges on the first opening and the second opening, respectively. Magnet,
The measurement site changing means is configured to displace only one of the first adsorbent holder and the second adsorbent holder.

The third invention is the first or second invention, a carrier gas flow rate measuring means for measuring a flow rate of the carrier gas supplied to the first adsorbent holder,
Flow rate control means for controlling the flow rate of the carrier gas supplied to the first adsorbent holder;
The measurement target gas concentration in the mixed gas of the carrier gas that is installed on the downstream side of the second adsorbent holder and flows out of the second adsorbent holder and the measurement target gas desorbed from the gas adsorbent Gas concentration detection means for detecting
Mixed gas supply means for supplying the mixed gas to the gas concentration detection means;
A mixed gas flow rate measuring means for measuring a flow rate of the mixed gas supplied to the gas concentration detecting means,
The flow rate control means controls the supply flow rate of the carrier gas so as to be a flow rate obtained by adding a predetermined excess flow rate to the flow rate of the mixed gas supplied to the gas concentration detection means.

  According to the first invention, the carrier gas is supplied to the gas adsorbent held by the first adsorbent holder and the second adsorbent holder, so that the measurement target gas adsorbed on the gas adsorbent is removed. Be released. The measurement site of the gas adsorbent is changed by displacing the first adsorbent holder and the second adsorbent holder by the measurement site changing means. Therefore, according to the present invention, by obtaining the mass of the measurement target gas desorbed from each of the plurality of measurement parts for each measurement part, the adsorption amount distribution of the measurement target gas adsorbed on the gas adsorbent can be obtained. Obtainable.

  According to the second invention, the first adsorbent holder and the second adsorbent holder are held via the gas adsorbent by the magnetic force of the pair of magnets. Further, when either one of the first adsorbent holder and the second adsorbent holder is displaced by the measurement site changing means, the other adsorbent holder is displaced following the magnetic force. For this reason, according to the present invention, the positioning of these holders can be easily performed, and furthermore, the measurement site can be changed by only displacing one of these holders. Thus, according to the present invention, the adsorption amount distribution of the gas adsorbent can be obtained with a simple and inexpensive configuration.

  According to the third invention, the first adsorbent holder and the second adsorbent are provided by supplying the first adsorbent holder with a carrier gas having a flow rate larger than the mixed gas flow rate supplied to the gas concentration detecting means. Inhalation of air from between the holder and the gas adsorbent can be prevented. For this reason, according to the present invention, it is possible to perform measurement with high accuracy without having to take measures such as correcting the influence of the measurement target gas contained in the atmosphere during measurement.

Embodiment 1 FIG.
FIG. 1 is a diagram for explaining the configuration of a gas adsorbent evaluation apparatus 10 according to Embodiment 1 of the present invention. The gas adsorbent evaluation apparatus 10 shown in FIG. 1 is a gas adsorbent, more specifically, a measurement target gas adsorbed by a filter 12 with activated carbon, more specifically, an adsorption amount distribution of evaporated fuel (THC). It is comprised as an apparatus for acquiring. The filter 12 with activated carbon in the present embodiment is arranged in an air cleaner of an intake passage of an internal combustion engine so as to adsorb evaporated fuel generated in the intake passage while the engine is stopped. In addition, the filter 12 in FIG. 1 is shown by the cross section cut | disconnected by the X direction shown in FIG. In FIG. 1, the perpendicular direction of the cross section of the filter 12 is referred to as a Y direction. The filter 12 includes a filtering unit 12a having predetermined dimensions with respect to the X direction and the Y direction.

  As shown in FIG. 1, the gas adsorbent evaluation apparatus 10 according to the present embodiment includes a measurement unit 14 that measures a sampling flow rate and a THC concentration for acquiring the THC adsorption amount adsorbed by the filter 12, and a measurement unit 14. The control part 16 which controls each component of these, and the data processing part 18 which processes the various data measured by the measurement part 14 are comprised.

  First, a specific configuration of the measurement unit 14 will be described. The measurement unit 14 includes a filter support 20 for fixing the filter 12. Further, the evaluation apparatus 10 includes a carrier gas supply pipe 22 that supplies zero gas as a carrier gas for desorbing THC to the filter 12. More specifically, in the present embodiment, purified air is used as such zero gas, and a purified air cylinder (illustrated) in which the upstream end of the carrier gas supply pipe 22 is filled with high-pressure purified air. (Omitted) is attached. The zero gas used here is not limited to purified air but may be based on an inert gas such as nitrogen.

  The carrier gas supply pipe 22 on the downstream side of the purified air cylinder is provided with an electromagnetic valve 24 for opening and closing the flow path. A mass flow controller 26 is installed in the carrier gas supply pipe 22 further downstream of the electromagnetic valve 24. The mass flow controller 26 measures and controls the flow rate of purified air flowing in the carrier gas supply pipe 22.

  A first adsorbent holder 28 is connected to the downstream end of the carrier gas supply pipe 22. More specifically, the portion of the carrier gas supply pipe 22 between the mass flow controller 26 and the first adsorbent holder 28 is configured by a flexible silicon tube 30. The first adsorbent holder 28 has a substantially prismatic outer shape, and a passage for purified air is secured therein. The first adsorbent holder 28 includes a rectifying plate 32 with a heater for rectifying and heating purified air introduced from the silicon tube 30 therein. The other end of the first adsorbent holder 28 is an open end, and the other end is referred to as a first opening 34 here. The opening area of the first opening 34 is configured to be equal to the division unit area of the filtration unit 12a divided into an appropriate number to obtain the adsorption amount distribution of the filter 12. A first magnet 36 is attached to the edge of the first opening 34.

  The gas adsorbent evaluation apparatus 10 of this embodiment includes a second adsorbent holder 38. The second adsorbent holder 38 has a second opening 40 formed with the same dimensions as the first opening 34. The second adsorbent holder 38 is arranged so that the second opening 40 faces the first opening 34 with the filter 12 interposed therebetween. Similar to the first opening 34, the second magnet 42 is attached to the edge of the second opening 40. Hereinafter, with reference to FIG. 2, the detailed structure of the 1st magnet 36 and the 2nd magnet 42 used by this embodiment is demonstrated.

  FIG. 2 is a diagram showing an example of the magnetic pole arrangement of the first magnet 36 and the second magnet 42 shown in FIG. More specifically, FIG. 2A is a view of the first magnet 36 viewed from the filter 12 side, and FIG. 2B is a view of the second magnet 42 viewed from the filter 12 side. is there. As shown in FIG. 2, the first magnet 36 and the second magnet 42 are each configured as a combination of unit magnets 44 arranged so that the magnetic poles are alternately switched. The magnetic pole arrangement is such that the opposing magnetic poles are different when the second magnet 42 is combined. By providing the magnets 36 and 42 having such a configuration, the first adsorbent holder 28 and the second adsorbent holder 38 are attracted to each other by the magnetic force through the filter 12. The cross-sectional shape of the holders 28 and 38 and the shape of the magnets 36 and 42 are not limited to a quadrangle, and may be a circle, for example.

  As shown in FIG. 1, the second adsorbent holder 38 is fixed to a holder support 46. The holder support 46 is attached to the actuator 48. The actuator 48 is configured to be able to displace the second adsorbent holder 38 fixed to the holder support 46 with respect to the X direction and the Y direction. A mixed gas conduit 50 through which a mixed gas of THC desorbed from the filter 12 and purified air flows is connected to the downstream end of the second adsorbent holder 38.

A mass flow meter 52 that measures the flow rate of the mixed gas is installed in the mixed gas pipe 50 on the downstream side of the second adsorbent holder 38. More specifically, a portion of the mixed gas pipe 50 between the second adsorbent holder 38 and the mass flow meter 52 is configured by a flexible hose 54 having flexibility. In the mixed gas pipe 50, a total hydrocarbon analyzer 56 for detecting the THC concentration in the mixed gas is installed further downstream of the mass flow meter 52. The total hydrocarbon analyzer 56 has a suction pump therein. Flow rate of the mixed gas taken into the total hydrocarbon analyzer 56 is controlled by the total hydrocarbon analyzer 56 to a predetermined set flow rate Q _b.

  The control unit 16 includes an operation panel 58 that accepts setting of predetermined measurement conditions, and a control circuit 60 that controls each component of the measurement unit 14. More specifically, the above-described solenoid valve 24, mass flow controller 26, actuator 48, mass flow meter 52, and total hydrocarbon analyzer 56 are connected to the control circuit 60.

  The data processing unit 18 includes a data processing circuit 62 that processes various data measured by the measuring unit 14, and a data display panel 64 that displays the distribution of the THC adsorption amount and the total adsorption amount calculated by the data processing circuit 62. It is comprised by. The data processing circuit 62 determines the flow rate (volume flow rate) of the mixed gas measured by the mass flow meter 52, the THC concentration in the mixed gas detected by the total hydrocarbon analyzer 56, and the THC density stored in advance. Based on the integrated time value, the amount of adsorption of THC at the measurement site previously positioned by the actuator 48 is calculated. As shown in FIG. 1, the data display panel 64 displays the adsorption amount of each measurement site by changing the density of the background color according to the density together with the numerical value.

  FIG. 1 shows a state in which the first adsorbent holder 28 and the second adsorbent holder 38 facing each other sandwich the filter 12 by magnetic force. When the second adsorbent holder 38 is displaced by the actuator 48 from such a state, the first adsorbent holder 28 moves following the second adsorbent holder 38. The first adsorbent holder 28 holds the filter 12 together with the second adsorbent holder 38 at the position where the second adsorbent holder 38 is newly positioned.

In the system of the present embodiment configured as described above, purified air is introduced into the carrier gas supply pipe 22 when the electromagnetic valve 24 is opened based on a command from the control circuit 60. The flow rate of the purified air introduced into the carrier gas supply pipe 22 is controlled by the mass flow controller 26 so as to be _a predetermined flow rate Qa. The purified air introduced into the first adsorbent holder 28 is supplied to the filter 12 while being heated by the rectifying plate 32 with a heater. As a result, desorption of HC adsorbed on the filter 12 is promoted. The desorbed THC becomes a mixed gas with purified air, and the mixed gas is sequentially introduced into the mass flow meter 52 and the total hydrocarbon analyzer 56 and then exhausted.

Further, in the system of the present embodiment, the flow rate Q _{a of} purified air supplied to the first adsorbent holder 28 is supplied to the total hydrocarbon analyzer 56 in order to maintain good measurement accuracy of the THC adsorption amount. the set flow rate Q _b of the mixed gas so that the flow rate obtained by adding a predetermined excess flow rate k, and controls the mass flow controller 26. A method for setting the excess flow rate k will be described. First, the filter 12 in a state before THC is adsorbed is set on the filter support 20, and the supply amount of purified air is gradually increased in that state. The flow rate of purified air when the THC concentration measured by total hydrocarbon analyzer 56 showed zero to determine the excess flow k such that the flow rate Q _a. According to such setting of the excess flow k, a large flow rate Q _a than the flow rate Q _b of the total hydrocarbon analyzer 56 is sucked by giving the side first holder 28, the holder 28 and 38 and the filter 12 It is possible to prevent air from being sucked in between. For this reason, it becomes possible to measure the adsorption amount of THC desorbed from the filter 12 with high accuracy.

Next, with reference to FIG. 3, a specific process for measuring the adsorption amount distribution of the activated carbon-attached filter 12 realized by the gas adsorbent evaluation apparatus 10 of the present embodiment will be described.
FIG. 3 is a flowchart of a routine executed by the control circuit 60 shown in FIG. 1 in order to realize the above function. Before the series of processes shown in FIG. 3 is executed, as a preliminary preparation, the power supply of the rectifier plate 32 with heater is turned on, and the filter 12 is set on the filter support 20. Then, predetermined measurement conditions necessary for measurement are input through the operation panel 58.

Specifically, the dimensions in the X direction and the Y direction of each measurement site in the filter 12, that is, the dimensions in the X direction and the Y direction of the openings 34 and 40 of the holders 28 and 38 are input. Next, the measurement order of each measurement site is input. Next, the measurement site switching condition is input. At this time, the operation panel 58 accepts a selection of whether to perform the switching based on the density C or based on the measurement time T. Further, the flow rate Q _b measured by the mass flow meter 52 and the excessive flow rate k are input. Next, the THC measurement range of the total hydrocarbon analyzer 56 selected from either automatic or fixed is input.

  When the measurement start is executed after the measurement conditions as described above are set, a series of processes of the routine shown in FIG. 3 is executed. First, calibration of the zero point and span point of the total hydrocarbon analyzer 56 is executed (step 100). Next, the first adsorbent holder 28 and the second adsorbent holder 38 are positioned (step 102). Specifically, the positions of the holders 28 and 38 are moved to a predetermined measurement site by the actuator 48 in accordance with a preset measurement order.

Next, the solenoid valve 24 is opened (step 104). Next, the acquisition and calculation of measurement data for the current measurement site are started (step 106). Specifically, the position information of the actuator 48, the flow rate Q _b by the mass flow meter 52, and the THC concentration by the total hydrocarbon analyzer 56 are taken into the data processing circuit 62. Then, the amount of THC adsorbed according to the measurement time is calculated from the time integrated value based on the flow rate Q _b , the THC concentration, and the density of THC.

Next, it is determined whether or not the instantaneous flow rate value Q _a of purified air measured by the mass flow controller 26 is equal to the sum of the set flow rate Q _b and the excess flow rate k (step 108). As a result, if it is determined that Q _a = Q _b + k does not hold, a warning is issued (step 110), and the current measurement is immediately terminated.

On the other hand, if the establishment of Q _a = Q _b + k is recognized in step 108, the measurement is continued, and then whether the instantaneous flow rate value of the mixed gas measured by the mass flow meter 52 is equal to the set flow rate Q _b It is determined whether or not (step 112). As a result, when the instantaneous flow rate value is determined not equal to the set flow rate Q _b, a warning is issued (step 110), the current measurement to an immediate end.

On the other hand, if it is determined in step 112 that the instantaneous flow rate value of the mixed gas is equal to the set flow rate Q _b , the measurement is continued, and then whether the measured value of the THC concentration is equal to or lower than the switching condition concentration C. Is determined (step 114). In the processing of this routine, the measurement site is switched based on a preset concentration C. That is, in the processing of this routine, such a concentration C is set as the measurement lower limit value, and the measurement for the measurement site of the filter 12 at this time is terminated when the measured value of the THC concentration becomes equal to or less than the concentration C. Note that, when zero gas is used as the carrier gas as in the system of the present embodiment, measurement may be performed until the THC concentration indicated by the total hydrocarbon analyzer 56 becomes zero. According to such a method, the total amount of THC adsorbed on the measurement site can be obtained. Further, as described above, the measurement site may be switched based on the measurement time T. That is, under the condition that the temperature of the rectifying plate 32 with the heater is constant and the mixed gas flow rate Q _b measured by the mass flow meter 52 is constant, the measurement is performed from each measurement part of the filter 12 during a predetermined measurement time T. The amount of THC to be detached may be measured.

  If it is determined in step 114 that the measured value of THC concentration ≦ the switching condition concentration C is satisfied, the electromagnetic valve 24 is closed (step 116), and the current measurement data is taken in and calculated for the measurement region of the filter 12. Stopped (step 118). Next, it is determined whether or not the current filter measurement part # is a preset final measurement part # (step 120). As a result, when it is determined that the current filter measurement site # is not the final measurement site #, the above-described processing of steps 100 to 120 is performed on the next measurement site according to a preset measurement order. .

  On the other hand, when it is determined in step 120 that the current filter measurement site # is the final measurement site #, the activated carbon filter 12 is applied to the activated carbon filter 12 based on the mass (adsorption amount) of THC desorbed from each measurement site. The adsorption amount distribution and total adsorption amount of the adsorbed THC are displayed on the data display panel 64 (step 122).

  As described above, according to the system of the present embodiment, the adsorption amount distribution of the evaporated fuel adsorbed by the activated carbon-attached filter 12 can be acquired. In the method of evaluating the adsorption amount distribution based on the difference in the weight value of the filter before and after the test, it is necessary to cut the filter in order to obtain the adsorption amount distribution. However, according to the evaluation apparatus 10 of the present embodiment, the filter 12 is damaged. Therefore, it is possible to accurately measure the adsorption amount distribution.

  In addition, according to the configuration of the present embodiment, the magnets 36 and 42 arranged with the magnetic poles different from each other are provided in the two holders 28 and 38, so that the holders 28 and 38 can be easily aligned. Furthermore, it is possible to change the measurement site only by displacing only the second adsorbent holder 38 by the actuator 48. For this reason, according to the system of the present embodiment, the adsorption amount distribution of the filter 12 can be grasped with a simple and inexpensive configuration.

  Further, in the evaluation apparatus 10 of the present embodiment, the filter 12 is sandwiched between the two holders 28 and 38, and further, the upstream first adsorbent holder 28 is compared with the downstream second adsorbent holder 38. As a result, a high flow rate corresponding to the excess flow rate k is given, so that THC in the atmosphere is not taken into the apparatus. For this reason, it is not necessary to correct the THC concentration in the atmosphere at the time of measurement, and there is no restriction on the measurement location where measurement must be performed in a clean chamber.

  In addition, in the case where the filter is disposed in the air cleaner of the internal combustion engine, such as the filter 12 with activated carbon of the present embodiment, the shape of the intake port, the mounting position of the filter 12 with activated carbon, and the like are different for each vehicle type. Generally, the adsorption amount distribution differs for each vehicle type. According to the system of this embodiment, since the adsorption amount distribution of the filter 12 can be grasped, for example, by taking a countermeasure such as adding more activated carbon to a portion where the adsorption amount is large, the activated carbon filter 12 It becomes possible to improve adsorption efficiency.

  By the way, in Embodiment 1 mentioned above, it is supposed that zero gas (purified air) is used as carrier gas supplied to the filter 12 with activated carbon, However, Carrier gas used by this invention is not limited to this. Any gas may be used as long as the concentration of the measurement target gas is equal to or lower than a predetermined measurement lower limit value (for example, the concentration C is equal to or lower than the above-described concentration C in the first embodiment).

  Moreover, in Embodiment 1 mentioned above, although the total hydrocarbon analyzer 56 is provided and the structure which measures the adsorption amount distribution of the evaporated fuel (THC) adsorbed by the filter 12 with activated carbon is shown, The gas to be measured is not limited to this, and may be, for example, CO, NO, or the like.

In the first embodiment described above, the purified air cylinder, the electromagnetic valve 24, and the mass flow controller 26 are the first magnet 36 and the second magnet 42 in the "carrier gas supply means" in the first invention. However, the actuator 48 is included in the “holder holding means” in the first invention, and the mass flow meter 52, the total hydrocarbon analyzer 56, and the data processing circuit 62 are included in the “measurement site changing means” in the first invention. The data display panel 64 corresponds to the “mass distribution display means” in the first invention, respectively, in the “gas mass acquisition means” in the first invention.
In the first embodiment described above, the mass flow controller 26 is the “carrier gas flow rate measuring means” and the “flow rate control means” in the third invention, and the total hydrocarbon analyzer 56 is the third invention. The “gas concentration detection means” in FIG. 5 is a suction pump provided in the analyzer 56, the “mixed gas supply means” in the third invention is the mass flow meter 52, and the “mixed gas flow rate measurement means in the third invention” is used. Respectively.

It is a figure for demonstrating the structure of the evaluation apparatus of the gas adsorbent of Embodiment 1 of this invention. It is a figure which shows an example of the magnetic pole arrangement | positioning of the 1st magnet shown in FIG. 1, and a 2nd magnet. It is a flowchart of the routine performed in Embodiment 1 of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Evaluation apparatus 12 Filter 24 with activated carbon Solenoid valve 26 Mass flow controller 28 1st adsorption material holder 34 1st opening part 36 1st magnet 38 2nd adsorption material holder 40 2nd opening part 42 2nd magnet 48 Actuator 52 Mass flow meter 56 Total hydrocarbon analyzer 60 Control circuit 62 Data processing circuit 64 Data display panel

Claims (3)

A carrier gas supply means for supplying a carrier gas for desorbing the measurement target gas to the gas adsorbent;
A first adsorbent holder that has a first opening that covers a part of the filtration area of the gas adsorbent, is installed downstream of the carrier gas supply means, and into which the carrier gas is introduced;
A second opening formed with substantially the same size as the first opening, and the second opening is arranged to face the first opening through the gas adsorbent; A second adsorbent holder,
Holder holding means for holding the first adsorbent holder and the second adsorbent holder pressed against the gas adsorbent;
Measuring part changing means for changing the measuring part of the gas adsorbent by displacing the first adsorbent holder and the second adsorbent holder;
A gas mass acquisition means installed on the downstream side of the second adsorbent holder for acquiring the mass of the measurement target gas desorbed from the measurement site;
A mass distribution display means for displaying a distribution of the mass for each of the measurement sites acquired by the gas mass acquisition means;
An apparatus for evaluating a gas adsorbent, comprising: The holder holding means is a pair of magnets arranged with different magnetic poles at the respective edges of the first opening and the second opening,
2. The gas adsorbent according to claim 1, wherein the measurement site changing unit is configured to displace only one of the first adsorbent holder and the second adsorbent holder. Evaluation device. Carrier gas flow rate measuring means for measuring the flow rate of the carrier gas supplied to the first adsorbent holder;
Flow rate control means for controlling the flow rate of the carrier gas supplied to the first adsorbent holder;
The measurement target gas concentration in a mixed gas of the carrier gas that is installed on the downstream side of the second adsorbent holder and flows out of the second adsorbent holder and the measurement target gas desorbed from the gas adsorbent Gas concentration detection means for detecting
Mixed gas supply means for supplying the mixed gas to the gas concentration detection means;
A mixed gas flow rate measuring means for measuring a flow rate of the mixed gas supplied to the gas concentration detecting means,
The flow rate control unit controls the supply flow rate of the carrier gas so as to be a flow rate obtained by adding a predetermined excess flow rate to the flow rate of the mixed gas supplied to the gas concentration detection unit. 3. The gas adsorbent evaluation apparatus according to 1 or 2.

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