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Title:
AN OIL PALM MILLING SYSTEM
Document Type and Number:
WIPO Patent Application WO/2012/026803
Kind Code:
A1
Abstract:
A system for continuous palm oil milling comprising a palm oil extraction unit extracting crude palm oil from sterilized detached fruits that the palm oil producing unit has an optimal capacity to process the sterilized detached fruits not higher than a predetermined volume; and a buffering unit, located upstream of the palm oil producing unit, which is configured to buffer the volume of sterilized detached fruits supplied to the palm oil extraction unit to approach the optimal capacity; wherein sterilized detached fruits have at least 90% of contained lipase being deactivated.

Inventors:
HONG, Lok, Choon (Pintas IP Group SDN. BHD, Suite 6.03 6th Floor,Wisma Miram, Jalan Wisma Putra Kuala Lumpur, 50460, MY)
ENG, Teoh, Guan (No. 3, Jalan SS22/44Damansara Jaya, Petaling Jaya, Selangor, 47400, MY)
YIN, Low, Teck (No. 6, Jalan Hujan Emas 6Taman Oug, Kuala Lumpur, 58200, MY)
Application Number:
MY2011/000196
Publication Date:
March 01, 2012
Filing Date:
August 25, 2011
Export Citation:
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Assignee:
HONG, Lok, Choon (Pintas IP Group SDN. BHD, Suite 6.03 6th Floor,Wisma Miram, Jalan Wisma Putra Kuala Lumpur, 50460, MY)
ENG, Teoh, Guan (No. 3, Jalan SS22/44Damansara Jaya, Petaling Jaya, Selangor, 47400, MY)
YIN, Low, Teck (No. 6, Jalan Hujan Emas 6Taman Oug, Kuala Lumpur, 58200, MY)
International Classes:
C11B1/10; A23D9/02; C11B1/02; C11B1/04; C11B1/06
Domestic Patent References:
2010-05-06
Foreign References:
GB2421169A2006-06-21
US5039455A1991-08-13
GB1040355A1966-08-24
Other References:
JAFFAR, A. ET AL.: 'Photogrammetric Grading of Oil Palm Fresh Fruit Bunches' INT. J. MECH. MECHATRONICS ENG. vol. 9, no. 10, 2009, pages 18 - 24
ABDULLAH, M. Z. ET AL.: 'The applications of computer vision system and tomgraphic radar imaging for assessing physical properties of food' J. FOOD ENG. vol. 61, 2004, pages 125 - 135
Attorney, Agent or Firm:
HONG, Lok, Choon (Pintas IP Group SDN. BHD, Suite 6.03 6th Floor,Wisma Miram, Jalan Wisma Putra Kuala Lumpur, 50460, MY)
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Claims:
CLAIMS

1. A system for continuous palm oil milling comprising

a palm oil extraction unit extracting crude palm oil from sterilized detached fruits that 5 the palm oil producing unit has an optimal capacity to process the sterilized detached fruits not higher than a predetermined volume; and

a buffering unit, located upstream of the palm oil producing unit, which is configured to buffer the volume of sterilized detached fruits supplied to the palm oil extraction

! unit to approach the optimal capacity; wherein sterilized detached fruits have at least 0 90% of contained lipase being deactivated.

2. A system of claim 1 further comprising a pre-treatment unit located upstream of the buffering unit to produce sterilized detached fruits from fresh fruit bunches attached With oil palm fruits by deactivating lipase activity in the oil palm fruits and/or

15 separating the oil palm fruits from the treated fresh fruit bunches.

3. A system of claim 1 or 2 further comprising grading means to sort the sterilized detached fruits according to ripeness and/or weight prior to delivering the sterilized detached fruits to the buffering unit.

20

4. A system of claim 1 or 2, wherein the buffering unit in communication and receives signal from the palm oil extraction unit to determine volume of the sterilized detached fruits to be discharged thereof.

A system of claim 1 or 2, wherein the buffering unit regulates a consistent supply of sterilized detached fruits to the palm oil extraction unit by storing sterilized detached fruits for a temporary duration and/or discharging the stored sterilized detached fruits to the palm oil extraction unit upon detecting the volume of sterilized detached fruits supplied to the palm oil extraction unit fallen below the predetermined volume.

6. A system of claim 1 or 2, wherein the buffering unit prioritizes discharge of sterilized detached fruits that sterilized detached fruits with better ripeness is discharged first. 7. A system of claim 2, wherein the pre- treatment unit employs pressurized steam to sterilize the oil palm fruits to deactivate the lipase activity.

8. A system of claim 2, wherein the pre-treatment unit employs boiled water to cook the oil palm fruits to deactivate lipase activity.

9. A system of claim 1 or 2, wherein the palm oil extraction unit uses screw press to extract palm oil from the sterilized detached fruits.

10. A system of claim 1 or 2, wherein the sterilized detached fruits are dried prior to storing in the buffer unit.

1 1 . A method of continuous palm oil milling process comprising the steps of

pre-treating fresh fruit bunches attached with oil palm fruits to deactivate at least 90% of lipase activity in the oil palm fruits;

acquiring sterilized detached fruits by separating the a oil palm fruits from the fresh fruit bunches that the sterilized detached fruits is used for palm oil production through a palm oil extraction unit is used, wherein the extraction unit has an optimal capacity to process oil palm fruits not higher than a predetermined volume;

buffering volume of the sterilized detached fruits being sent to the extraction unit via a buffering unit; and

extracting palm oil from the oil palm fruits using the extraction unit.

12. A method of claim 9 further comprising the step of sorting the collected oil palm fruits according to ripeness and/or weight of the fruits prior to delivering the fruits to the buffering unit.

13. A method of claim 11 or 12, wherein the buffering unit regulates a consistent supply of sterilized detached fruits to the palm oil extraction unit by storing sterilized detached fruits for a temporary duration and/or discharging the stored sterilized detached fruits to the palm oil extraction unit upon detecting the volume of sterilized detached fruits supplied to the palm oil extraction unit fallen below the predetermined volume.

14. A method of claim 9 or 10, wherein the pre-treating step uses pressurized steam to sterilize the oil palm fruits to deactivate the lipase activity.

15. A method of claim 9 or 10, wherein the buffering unit prioritizes discharge of oil palm fruits that oil palm fruits with better ripeness is discharged first.

Description:
AN OIL PALM MILLING SYSTEM

FIELD OF INVENTION

This invention relates to oil palm milling and, more particularly, to a method of operating an 5oil palm mill utilizing its optimum capacity for more time than is possible with current operating practices.

BACKGROUND TO THE INVENTION

Delivery of oil palm fruit bunches to oil palm mills is frequently patchy since fruit production lOis not consistent, being seasonal and weather dependant and also being subjected to random delays or other failures in shipping the bunches to the mills. Further, the fresh fruit bunches are subjected to enzymatic degradation upon collection from the oil palm tree and needed to be processed as soon as possible. Thus, oil palm mills has to be designed with higher capacity to anticipate maximum input instead of having smaller capacity to handle only the averaged 15input of the raw material. Such uneconomic practice means that at times a mill may be working for only a part of the day and will be standing idle for the rest of the time while waiting for new deliveries of fruit bunches. During those idle periods the mill cannot be shut down as it is not easy to predict the arrival or amount of the coming raw material. Shut down and start up procedures are time consuming and costly. Salary still have to be made to the 20operating staff even in the idle period.

It is known the palm fruit cannot be kept for long periods and currently must be processed as soon as possible after delivery to the mill to avoid increase of free fatty acid content caused by the lipase in the fruit. It would be highly desirable if a method could be found to retard the 25degradation of the oil palm fruit so that it can be stored for a reasonable period to be passed to the mill some days after delivery to even out the periods of operation of a mill so that operation is not dependant on regular deliveries of consistent quantities of the oil palm fruit bunches. If this is possible it means that mills could be smaller with consequent lower building and operating costs, which would result in great economic advantages to the palm oil industry. This invention provides such a method. SUMMARY OF THE INVENTION

The present invention aims to provide a system for effective oil palm milling that the disclosed system requires less capital input, particularly in terms material, capital and labour, for any given output compared to current system practicing in oil palm milling. Another object of the present invention is to disclose a palm oil milling system which can operate in a continuous process flow and free from the influence of short disruption in fresh fruit bunches supply. More specifically, the disclosed system employs a buffering unit to ensure a controlled and sustaining feed of oil palm fruits for the continuous extraction process that the feed shall always aim to meet the optimal processing capacity of the disclosedsystem.

Still another object of the present invention is to offer a method of oil palm milling that the method can be applied to the abovementioned system or any other standalone systems. Through the disclosed method, the raw material or pre-treated palm oil fruit is continuouslyfed to the extraction unit at a sustainable rate to ensure the milling process can carry on regardless any disruption in the fresh fruit bunches supply.

Further object of the disclosed invention is to offer an approach to effectively handle sudden inflow of fresh fruit bunches during the peak of fruit harvesting season. Through the presentinvention, only significantly small storage space required compared to conventional practice. The present invention keeps only the pre-treated sterilized detached fruits, which constitutes 40% of total volume of fresh fruit bunches, instead of storing the whole fresh fruit bunches commonly performed in conventional milling. At least one of the preceding objects is met, in whole or in part, by the present invention, in which one of the embodiments of the present invention is a system for continuous palm oil milling comprising a palm oil extraction unit extracting crude palm oil from sterilized detached fruits that the palm oil producing unit has an optimal capacity to process the sterilized detached fruits not higher than a predetermined volume; and a buffering unit, located upstream of the palm oil producing unit, which is configured to buffer the volume of sterilized detached fruits supplied to the palm oil extraction unit to approach the optimal capacity without exceeding to predetermined volume; wherein sterilized detached fruits have at least 90% of contained lipase being deactivated.

In another aspect, the disclosed system may comprise a pre-treatment unit located upstream of the buffering unit to produce sterilized detached fruits from fresh fruit bunches attached with oil palm fruits by deactivating lipase activity in the oil palm fruits and/or separating the oil palm fruits from the treated fresh fruit bunches.

To attain the buffering effect, in the preferred aspect, the buffering unit regulates a consistent supply of sterilized detached fruits to the palm oil extraction unit by storing sterilized detached fruits for a temporary duration and/or discharging the stored sterilized detached fruits to the palm oil extraction unit upon detecting the volume of sterilized detached fruitssupplied to the palm oil extraction unit fallen below the predetermined volume.

Still another aspect of the present invention may have a grading means incorporated to the disclosed system to sort the sterilized detached fruits according to ripeness and/or weight prior to delivering the sterilized detached fruits to the palm oil extraction unit and/orbuffering unit.

To have the palm oil milling continuously performed at the optimal capacity, the buffering unit plays an important role in regulating a consistent supply of sterilized detached fruits to the palm oil extraction unit, preferably, by storing sterilized detached fruits for a temporaryduration and/or discharging the stored sterilized detached fruits to the palm oil extraction unit upon detecting the volume of sterilized detached fruits supplied to the palm oil extraction unit fallen below the predetermined volume.

Fruit with over-ripeness caused by prolonged storage may diminish the effort of present 5 invention to attain optimal output from a palm oil mill. To avoid such condition, the buffering unit prioritizes discharge of oil palm fruits that oil palm fruits with better ripeness is discharged first.

lOStill another major embodiment of the present invention is A method of continuous palm oil milling process comprising the steps of pre-treating fresh fruit bunches attached with oil palm fruits to deactivate at least 90% of lipase activity in the oil palm fruits; acquiring sterilized detached fruits by separating the a oil palm fruits from the fresh fruit bunches that the sterilized detached fruits is used for palm oil production through a palm oil extraction unit is

15 used, wherein the extraction unit has an optimal capacity to process oil palm fruits not higher than a predetermined volume; buffering volume of the sterilized detached fruits being sent to the extraction unit via a buffering unit; and extracting palm oil from the oil palm fruits using the extraction unit.

20Another aspect of the disclosed method may additionally have a step of sorting the collected oil palm fruits according to ripeness and/or weight of the fruits prior to delivering the fruits to the screw pressing apparatus and/or buffering unit.

In further aspect, the buffering unit used in the disclosed method shall prioritize discharge of 25oil palm fruits that oil palm fruits with better ripeness is discharged first.

DETAILED DESCRIPTION OF THE INVENTION

It is to be understood that the present invention may be embodied in other specific forms and is not limited to the sole embodiment described herein. However modification and equivalents of the disclosed concepts such as those which readily occur to one skilled in the art are intended to be included within the scope of the claims which are appended thereto.

The term "sterilized detached fruits" used herein throughout the description refers to fruitlets 5 separated from the fresh fruit bunch stalks of the oil palm tree and being treated by any known approach to deactivate at least 90% of lipase activity contained in the fruitlets.

The present invention includes a system for continuous palm oil milling comprising a palm oil extraction unit extracting crude palm oil from sterilized detached fruits that the palm oil lOproducing unit has an optimal capacity to process the sterilized detached fruits not higher than a predetermined volume; and a buffering unit, located upstream of the palm oil producing unit, which is configured to buffer the volume of sterilized detached fruits supplied to the palm oil extraction unit to approach the optimal capacity; wherein sterilized detached fruits have at least 90% of contained lipase being deactivated.

15

In further embodiment, a pre-treatment unit is located upstream of the buffering unit to produce sterilized detached fruits from fresh fruit bunches attached with oil palm fruits by deactivating lipase activity in the oil palm fruits and/or separating the oil palm fruits from the treated fresh fruit bunches. More preferably, the pre-treatment unit is in connection to the 20buffering unit only without directly delivering the fruits to the extraction unit that the buffering unit serves the function to control and manage the supply of sterilized detached fruits to the extraction unit. Such arrangement shields the downstream production from being affected by any disruption in the upstream pre-treatment unit.

250ne of the embodiment of the present invention may further comprise a grading means to sort the collected oil palm fruits according to ripeness and/or weight of the fruits prior to delivering the fruits to the extraction unit and/or buffering unit. More particularly, the ripeness of fruits may be determined by a machine via assessing physiochemical properties of the fruits. For example, the electrical current can be conducted through fruit sample of a

30batch of received fresh fruit bunches that resistance generated in the fruits can be used as an indicator to determine ripeness. Apart from that, colour, weight, level of specific enzyme activity can be used as well in determining the stage of ripeness.

It is important to be noted that the present invention can greatly reduce the required capital 5investment, particularly machinery and labour capacities, in any palm oil milling plant through incorporation of the buffering unit in the palm oil milling system. The buffering unit protects the palm oil mills from being impeded by irregular fresh fruit bunches supply. More specifically, the buffering unit used in the described system regulates a consistent supply of sterilized detached fruits to the palm oil extraction unit. This can be done by storing sterilized lOdetached fruits for a temporary duration and/or discharging the stored sterilized detached fruits to the palm oil extraction unit upon detecting the volume of sterilized detached fruits supplied to the palm oil extraction unit fallen below the predetermined volume. The buffering unit can refer to any means with storage facility such as tank or canister. The buffering unit may be composed of one or more storage tanks for storing of palm oil fruits according to

15different physical characteristics of the fruits such as weight and ripeness. For example, fruits with good ripeness and under-ripeness may be stored at different storage tanks to facilitate the logistic in delivering the fruits to the extraction unit. Further, the disclosed invention ensures all processing equipment associated with the system or so are less strained as the buffering unit always ensure the equipment are not overloaded in this continuous milling

20process. The occasion to shut down the mill for equipment maintenance is significantly lower than the conventional system.

One skilled in the art should appreciate the fact that the disclosed system can be constituted 25of multiple pre-treatment unit, buffering units and extraction unit. In more specific, one or more buffering unit may be arranged to receive pre-treated oil palm fruits from one or more pre-treatment unit and delivers the sterilized detached fruits to one or more extraction unit for oil extraction. The combinations of various sections and units may form the processing network involving complex logistic set up. Geographical distance in between the units shall 30pose no limitation to the present invention as vehicle can be used to transport the sterilized detached fruit from one location to another apart from using conventional conveying system. With incorporation of an appropriate level of control automation in the system, the downstream extraction process in the extraction unit can substantially operate independently without being affected by disruption in fresh fruit bunches supply at the upstream pre- 5treatment unit. Literally, the stored pre-treated oil palm fruits are employed as the input raw material to sustain the continuity of the milling process rather than using the fresh fruit bunches. The system preferably demand the processing sections and buffering units physically separated albeit interconnected via conveyors. The buffering unit facilitates the independent operation of the extraction unit and the first/second section within the limitation lOof the storage capacity. Preferably, the buffering unit is in communication and receives signal from the palm oil extraction unit to determine volume of the sterilized detached fruits to be discharged thereof. For example, a control panel may continuously measure and calculate the required volume of sterilized detached fruits to be supplied to the extraction unit to maintain the optimal output and generating a signal to be sent to the buffering unit to control the

15 amount of sterilized detached fruits to be discharged thereof.

Pursuant to the another preferred embodiment, the buffering unit has a controlled storage environment meeting the need to prolong storage life of the fruits. For example, the storage tank used as the buffering unit may store the fruit at a lower temperature compared to the

20external environment to further inhibit enzyme activity of the remaining lipase in the fruits but not too low until leading to crystallization of oil contained in the fruits. More preferably, the storage tank has reduced moisture content to prevent growing of mould on the surface of the fruits. The controlled environment within the buffering unit may be regulated also in line with the ripeness of the stored fruit. Preferably, the fruit with better ripeness may be kept at a

25much lower temperature to diminish the lipase activity. Drying the sterilized detached fruits or oil palm fruits prior to storing it in the buffer unit is another way in the present invention to retard mould growth.

With consistent supply of sterilized detached fruits to match the optimal capacity of the 30extraction unit, the crude palm oil and/or palm kernel oil throughput of the disclosed system in any given period is not compromised due to relatively lower machinery and labour input. Instead, the disclosed system can outrun any conventional system, which has substantially similar capacity, in crude palm oil throughput. In contrast to conventional flow process system suffered from frequent idling time caused by irregular fresh fruit bunches deliveries, 5the disclosed system can perform with longer operational time with less idling occasion assisted by stable and regulated oil palm fruits supply. It was found by the inventors of the present invention that the positioned downstream extraction unit can always perform at the optimal capacity in the presence of the buffering unit as described. The downstream extraction unit can operate substantially independent without suffering from irregular supply lOof fresh fruit bunches at the upstream process as long the buffering unit contains enough volume of stored sterilized fruit bunches to buffer activities conducted in the extraction unit.

To avoid decomposition of over-ripe fruits during the storage life, the buffering unit of the disclosed system prioritizes discharge of oil palm fruits. Preferably, oil palm fruits with better 15ripeness is discharged first to the extraction unit for palm oil extraction. Such feature may be enabled by storing the fruit of various ripeness in different buffering units and discharging the fruits accordingly.

As in the foregoing description, the pre-treatment unit aims to prohibit further lipase activity 20in the oil palm fruits by applying sufficient heat to degrade the enzyme. More preferably, the pre-treatment unit may comprise a steam sterilizer, either horizontal or vertical, which employs pressurized steam to heat or sterilize the fresh fruit bunch and the attached oil palm fruits. The sterilization process ensures sufficient heat penetrated through the fruits to deactivate the lipase contained within. Besides, the deactivation can be performed as well 25through cooking the fresh fruit bunches in hot water. The steam or hot water also further break-up complex carbohydrate polymer in the fresh fruit bunches to smaller sugars polymer facilitating subsequent fruit separation process. The pre-treatment unit may include the process of cleaning dirt off the fruit prior the storing. The pre-treatment unit may also include, but not limited to, a threshing machine to remove the sterilized or treated fruits from 30the stalk. Other known approaches capable of separating the fruits from the stalks to produce sterilized detached fruit can be used in the pre-treatment too. It is important to be noted that the sterilizer and threshing machine of the pre-treatment unit can be physically separated from one another or combined into a single unit. Subsequently, the palm oil extraction unit in the disclosed system preferably includes a screw pressing machine, more preferably a twin screw design, to extract palm oil from the sterilized detached fruits. To ease the extraction process, the extraction unit may further include a digester to heat the fruit using steam while beating the fruits to disrupt the oil bearing cells in the fruits. The digester prepares the fruits for the oil extraction aiming to acquire better yield.

Depending on the milling capacity, ripeness of the fruits and the storing condition in the buffering unit, the temporary duration for storing the sterilized detached fruits or pre-treated oil palm fruits in the buffering unit can range between an hour to two weeks.

Still another embodiment disclosed in the present invention is a method of continuous palm oil milling process which can be applied or used in conjunction with the system described above. The method comprises the step of pre-treating fresh fruit bunches attached with oil palm fruits to deactivate at least 90% of lipase activity in the oil palm fruits; acquiringsterilized detached fruits by separating the a oil palm fruits from the fresh fruit bunches that the sterilized detached fruits is used for palm oil production through a palm oil extraction unit is used, wherein the extraction unit has an optimal capacity to process oil palm fruits not higher than a predetermined volume; buffering volume of the sterilized detached fruits being sent to the extraction unit via a buffering unit; and extracting palm oil from the oil palm fruitsusing the extraction unit.

According to another preferred embodiment, the method of the present invention may have additional step of sorting the collected oil palm fruits according to ripeness and/or weight of the fruits prior to delivering the fruits to the palm oil extraction unit and/or buffering unit. As setting forth, the sorting can be performed using a machine or a grading means to assess physiochemical properties of the fruits such as colour, electrical conductivity, weight, hardness, enzyme activity and so on. Sorting of the fruits allows buffering of the milling process attained in a much controlled manner, particularly avoid decomposition of over- ripped fruits during storage within the buffering unit. The over-ripe fruits has the priority to 5be processed by the palm oil extraction unit first followed by fruits with less ripeness.

Additionally, in one embodiment, the method includes a step of prioritizing discharge of oil palm fruits stored in the buffering unit. Preferably, sterilized detached fruits with better ripeness is discharged first to the palm oil extraction unit. A plurality of buffering unit may lObe used to store the fruit of various ripeness to carry out the prioritizing step. More preferably, sterilized detached fruits with better ripeness stored in the multiple buffering unit will have the priority to be discharged first for oil extraction.

In line with above description, the buffering unit used in this method has a controlled storage 15environment meeting the need to prolong storage life of the fruits. For example, the buffering unit lower the storing temperature to inhibit enzyme activity of the remaining lipase in the fruits. More preferably, the storage tank has reduced moisture content to prevent growing of mould on the surface of the fruits. The controlled environment within the buffering unit may be regulated also in line with the ripeness of the stored fruit. Preferably, the disclosed method 0may opt to dry the sterilized detached fruits prior to storing it in the buffer unit to retard mould growth.

With the aide of the buffering unit, the disclosed method secure a consistent supply of sterilized detached fruits or pre-treated palm oil fruits to match the optimal capacity of the 5extraction unit. The crude palm oil and/or palm kernel oil production via the disclosed method in any given mills and period is not compromised due to relatively lower machinery and labour input. In contrast to conventional flow process suffered from frequent idling time caused by irregular fresh fruit bunches deliveries, the disclosed method allow the milling to be performed with longer operational time with less idling occasion caused by stable and 0regulated oil palm fruits supply. Preferably, the buffering unit stores the collected oil palm fruits for a temporary duration once supply of oil palm fruits to the extraction unit exceed the predetermined volume and/or discharges the stored oil palm fruits to the extraction unit upon detecting the volume of oil palm fruits supplied to the extraction unit fallen below the predetermined volume

One of the embodiments of the present invention, the pre-treating step is done by pressurized 5steam sterilization to deactivate the lipase activity that a sterilizer is employed. Similar result can be achieved by cooking the fresh fruit bunches in hot water besides steam sterilization. Washing or cleaning of the fruits may be imparted as the pre-treating steps as well.

According to the invention, on arrival of a delivery of oil palm fresh fruit bunches at an oil lOpalm mill the fruit are stripped from the bunches after being subjected to steam sterilisation to an extent sufficient to inhibit any enzymatic activity, following which the sterilised detached fruit are passed to a storage unit where it is stored until it is required to be sent to the mill for oil extraction, the stored fruit being used in increasing sequence of sterilisation and storage date. It will be seen that by operating an oil palm mill in the manner described, peaks and 15troughs in the amount of fruit available for oil extraction will be largely eliminated and the mill operator will have far greater flexibility in the way that he/she operates to ensure that the mill is operated at its most profitable regardless of fruit deliveries.

Practicing of the buffering step or buffering unit in the disclosed invention secure a 20continuous milling process, irrespective of irregular fresh fruit bunches deliveries and significantly improves mill productivity. Such design requires less resource input without diminishing the throughput of a mill via a longer effective operational time compared to frequent idled system in conventional mills.

25The present disclosure includes as contained in the appended claims, as well as that of the foregoing description. Although this invention has been described in its preferred form with a degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangements of parts may be resorted to without departing from the

30scope of the invention