NO20170156A1 - A sample coffee roasting device - Google Patents

Abstract

A sample coffee roasting device comprising a roasting chamber arranged to hold a sample of coffee beans; a heating element; an air inlet channel configured to guide heated air from the heating element into the roasting chamber; paddles rotatable about a center, for continuous shifting of the coffee beans inside the roasting chamber, the paddles comprising blades; an air exit channel, for exhausting air and residue from the roasting chamber. The sample coffee roasting Device comprises a first temperature sensor arranged to measure a temperature of the sample of coffee beans, the first temperature sensor protruding into the roasting chamber and configured for being covered by the coffee beans located in a lower part of the roasting chamber; the blades of the paddles are planar and aligned perpendicular to the direction of movement, for even distribution of the coffee beans inside the roasting chamber.

Description

A sample coffee roasting device

Field of the invention

The invention relates to a coffee roaster and, more particularly, to a sample coffee roasting device for roasting coffee beans.

Background of the invention

Coffee roasting is the process of heating a batch of coffee beans, in order to develop the flavor of the coffee beans. Among others, temperature, airflow and time affect the outcome of a coffee roast. During the coffee roasting, chaff, the dried skin surrounding green coffee beans, is separated from the beans.

To evaluate the quality and taste of different coffee harvests or equivalent, small samples of around 100 grams of coffee beans are roasted and later tasted in a session called cupping. For cupping purposes it is crucial that each coffee sample is roasted as consistently as possible. Furthermore, the coffee should be roasted in such a way as to be able to detect faults and flaws, while the natural flavors and aromas are accentuated.

Open drum sample roasters are the most widely used for sample roasting coffee beans. Drum roasters consist of a rotating cylindrical drum, with heat being applied either directly under the drum or through the center through a conduit. The heat is transferred from the heat source to the coffee beans through both conduction and convection. The rate at which energy is transferred by conduction and convection to the coffee beans, depends on how the drum roaster is operated, making it challenging to roast consistently. For sample roasting in an open drum roaster, the low mass of coffee beans often makes it hard to measure the bean temperature in a way that gives a reliable result.

In open drum sample roasters the front of the drum is open and ambient air from the surroundings is constantly entering the open drum due to a slight negative air pressure inside the drum, caused by an exhaust fan. This constant interference makes it challenging to accurately measure the environmental temperature inside the drum roaster. Open drum sample roasters are manually operated, and thus the operation is time consuming and requires a skilled operator. It is hard to roast consistently with high quality even for skilled operators, thus making it unnecessary challenging to evaluate the coffee. The advantages of these roasters are that the operator can inspect samples through vision and smell, and that the roasters can roast back to back, i.e. continually, since the beans are cooled in a separate cooling tray.

Fluid bed roasters have been known to solve some of the problems related to open drum roasters, by creating a more controllable environment. In fluid bed roasters the heat is transferred to the coffee beans mainly through hot air, i.e. convection. A fluid bed roaster system consists of a tall cylinder that allows hot air to flow through a chamber, providing a homogeneous distribution of heat. For fluid bed roasters the environment temperature is easier to control, but for small volumes of coffee beans, the actual bean temperature is hard to measure. Most fluid bed roasters also lack a way of extracting a sample during the roasting process, and often the beans are cooled within the roasting chamber, preventing back to back roasting.

Summary of the invention

The objective of the present invention is to provide a sample coffee roasting device designed to roast small samples of coffee beans consistently. The heat is primarily transferred through air, and the roaster can accurately measure the coffee bean temperature as well as an ambient temperature in the roasting chamber, even for small samples or batches of coffee beans. This enables the roaster to roast coffee beans based on predefined temperature profiles, and enables a user to roast consistent with less manual labor. The roasting can be done either manually, semiautomatic or fully automatic, and allows unexperienced users to roast good coffee, because of a low threshold for applying and supervising the coffee roasting process.

The coffee roaster is further constructed such that qualities like visual inspection and odor control from traditional sample roasters is still present, but unwanted odors from the roasting process is ventilated through the ventilation system. The level of noise from the machine during roasting is also very low compared to traditional sample roasters.

A sample of coffee beans can at any time be extracted from the roaster without interrupting the roasting process, and a separate ventilation system for the roasting chamber and the cooling tray ensures back to back roasting.

In accordance with the present invention, there is provided a sample coffee roasting device comprising a roasting chamber arranged to hold a sample of coffee beans; a heating element; an air inlet channel configured to guide heated air from the heating element into the roasting chamber; paddles rotatable about a center, for continuous shifting of the coffee beans inside the roasting chamber, the paddles comprising blades; an air exit channel, for exhausting air and residue from the roasting chamber. The sample coffee roasting device further comprises a first temperature sensor arranged to measure a temperature of the sample of coffee beans, the first temperature sensor protruding into the roasting chamber and configured for being covered by the coffee beans located in a lower part of the roasting chamber; the blades of the paddles are planar and aligned perpendicular to the direction of movement, for evenly distribution of the coffee beans inside the roasting chamber.

According to another embodiment of the invention, the roasting device further comprises a discharge mechanism configured to discharge the coffee beans from the roasting chamber.

According to another embodiment of the invention, the discharge mechanism comprises a side wall portion configured to move relative to the roasting chamber.

According to another embodiment of the invention, the discharge mechanism further comprises first and second rotary elements configured to rotate the side wall portion of the roasting chamber.

According to another embodiment of the invention, a second temperature sensor is located in the upper part of the roasting chamber, for measuring an environmental temperature.

According to another embodiment of the invention, the heating element and the air inlet channel extend along the depth of the roasting chamber.

According to another embodiment of the invention, the roasting device further comprises a container with a perforated base configured for cooling the sample coffee beans.

According to another embodiment of the invention, a fan in the roasting device provides a flow of air through the cooling container and the coffee beans.

According to another embodiment of the invention, the air inlet channel is located in a lower part of the roasting chamber.

According to another embodiment of the invention, the inlet channel comprises prongs provided to create a homogenous flow of hot air into the roasting chamber.

According to another embodiment of the invention, the air exit channel is located in the roasting chamber substantially opposite of the air inlet channel, for ensuring a steady flow of heated air through the roasting chamber.

According to another embodiment of the invention, the discharge mechanism is controllable by a user and by the roasting device, the roasting device is provided to activate the discharging mechanism according to a predetermined setting.

According to another embodiment of the invention, the weight of the sample of coffee beans is 100 grams.

Brief description of the drawings

These and other characteristics of the invention will become clear from the following description of embodiment(s), given as non-restrictive examples, with reference to the attached schematic drawings. Figure 1 is a perspective view of the coffee roaster, where the front, top and right side is visible. Figure 2 is a front view of the coffee roaster, where the front and top panels are removed for illustrating purposes. The interior of the coffee roaster, and the roasting chamber where the coffee beans are roasted, is thus shown. The roasting chamber is in a closed state. Figure 3 is a perspective view of the front of the coffee roaster, where the front and top panels are removed for illustrating purposes. A side panel of the roasting chamber wall is in a tilted position, and the roasting chamber is in an open state. In this state, the coffee beans are discharged from the roasting chamber into a tray. Figure 4 is a perspective view of the coffee roaster, where the front, top and side panels are removed for illustrating purposes. The roasting chamber is in a closed state, and further details of the interior of the coffee roaster are shown. Figure 5 is a cross section view of the coffee roaster, seen from the left side of the coffee roaster. In this view, an air exit channel, a cyclone and further details are visible.

Detailed description of preferred embodiments

The following description may use terms such as "horizontal", "vertical", "left", "right", "upper", "lower", "inner", "outer", "forward", "rear", etc. These terms generally refer to the views and orientations as shown in the drawings and that are associated with a normal use of the invention. The terms are used for the reader's convenience only and shall not be limiting.

Figure 1 shows a coffee roaster 1 for small batch roasting. The coffee roaster 1 comprises an inlet opening 2 where a user of the coffee roaster 1 feeds coffee beans into the roaster 1. The inlet opening 2 is basically an opening which directs the coffee beans into the interior and a coffee roasting chamber (explained with reference to figure 2 and figure 3) of the coffee roaster 1, and is in the illustrated embodiment simply an opening in the top panel of the coffee roaster 1, with a protruding cylindrical portion along the edge of the opening 2. The cylindrical portion could also be funnel shaped, or have any other configuration, and the inlet opening 2 could also be place elsewhere on the coffee roaster, as is commonly known in the art. An inlet lid 3 prevents coffee beans and air from unintentionally entering the roasting chamber, and also prevents chaff and exhaust heat from exiting the coffee roaster through the inlet opening 2. This inlet lid 3 is explained more in detail with reference to figure 2 and figure 3. In figure 1, the inlet lid 3 protrudes at an angle through a slot in the top panel of the coffee roaster 1, such that the inlet lid 3 can easily be manipulated, i.e. pulled out and pushed in, by a user. In figure 1, the top part of the inlet lid 3 is visible.

A digital display 4, in the illustrated embodiment placed on the front face of the coffee roaster 1, can display temperature settings, time, and different input and output in relation with the roasting process. Other units and measures necessary for the user to be able to monitor the coffee roasting process can also be displayed. The display 4 can be of the touch type, such that a user can input data directly on the display to adjust the different input variables of the process.

A sampler 5 is in the illustrated embodiment also positioned on the front face of the coffee roaster 1. The sampler 5 extends into the coffee roasting chamber, and allows the user to extract a small sample of coffee beans from the roasting chamber, such that the quality can be manually examined without aborting or interrupting the roasting process. The sampler 5 comprises a handle and an extended portion comprising a cylindrical portion where a 1/4 or a V* or similar portion is cut from the cylinder. When positioned in the coffee roaster 1, the cut, cylindrical portion is positioned in the roasting chamber. Upon turning the sampler 5 and allowing a few coffee beans to enter the cut cylindrical portion of the sampler 5, the coffee beans are collected and can be extracted from the roasting chamber when the sampler 5 is pulled out from the front panel of the coffee roaster 1. Such a way of collecting a sample of coffee beans is known in the art.

An inspection window 6 allows the user to visually monitor the coffee beans while they are being processed in the roasting chamber. The inspection window 6 is a glass panel on the front face of the coffee roaster 1, with the roasting chamber located directly behind. In the illustrated embodiment, the inspection window 6 is positioned in the lower, left quarter of the roasting chamber; this is where the coffee beans will primarily be located in the roasting chamber during roasting, as is explained more in detail with reference to figure 2.

A tray 7 is positioned below the roasting chamber. When the roasting chamber is emptied, the roasted coffee beans will fall down and be collected in the tray 7. The tray 7 comprises a perforated base, and the coffee beans are cooled in the tray 7 until they are ready to be processed further. A new batch of coffee beans can be roasted in the coffee roaster while a previous batch is cooled in the tray 7, such that a process of continuous roasting is possible. Below the tray 7, a fan is mounted in the coffee roaster. The fan sucks air through the coffee beans and the perforated base, and thus the beans are cooled. The air from the coffee beans cooling fan is guided through the coffee roaster and exhausted on the back of the roaster, as is explained more in detail with reference to figure 4. The time and speed of the coffee bean cooling fan can be adjusted via the digital display 4.

A discharge handle 8 is located on the front panel of the coffee roaster 1. When activated, the discharge handle 8 provides opening of the roasting chamber such that the coffee beans are discharged from the roasting chamber and into the tray 7 below. The mechanism which is activated upon movement of the discharge handle 8 is further described with reference to figure 2 and 4. The discharge handle 8 is moved in an arcuate movement in an are shaped slot 9.

A rotary knob 10 on top of the coffee roaster can be used together with the display 4. The effect of the rotary knob 10 can be set on the display, and the rotary knob 10 can be turned for both quick adjustments and fine-tuning. Typically, the temperature, speed, etc. can be set to be adjusted by the rotary knob 10.

Figure 2 is a front view of the coffee roaster 1, with the top and front panels of the coffee roaster 1 removed for illustrating purposes. The coffee roaster 1 in figure 2 is in a closed state, i.e. the inlet lid 3 is in a closed state, and a side wall portion 18 is also in a closed state such that the roasting chamber 12 is closed. Upon roasting, coffee beans are fed into the apparatus through the inlet opening 2 as described with reference to figure 1. The coffee beans are thus fed into a storing chamber 11, where they are stored until further action is performed by the user. The storing chamber 11 is formed by the inlet lid 3, a side wall portion 18, and front and rear walls. The front wall is in figure 2 not visible for illustrating purposes. When the inlet lid 3 is pulled by the user in the direction indicated by arrow A in figure 2, the coffee beans are fed from the storing chamber 11 into roasting chamber 12. When the coffee beans have been fed into the storing chamber 12, the inlet lid 3 should be placed in its initial position, i.e. pushed back into the coffee roaster 1 until it comes into contact with the side wall portion 18. The side wall portion 18 also comprises a circular wall portion 25.

In the closed state shown in figure 2, a first rotary element 20 biases the side wall portion 18 towards the roasting chamber wall 31, such that the circular wall portion 25 abuts the roasting chamber wall 31, and the walls circumscribing the roasting chamber 12 are thus closed. In figure 2, the first rotary element 20 has been rotated clockwise to the right in order to achieve this biasing effect, and the first rotary element 20 will stay in this position as long as the discharge handle 8 is in the locking position, i.e. in the position shown in figure 1 and 2. The roasting chamber 12 is the space in the coffee roaster 1 where the coffee beans are roasted, and this space is defined by the roasting chamber wall 31, side wall portion 18 and front and back walls. In order to prevent coffee beans being stuck or damaged in the joint between the roasting chamber wall 31 and the circular wall portion 25 of the side wall portion 18, this joint is positioned a distance up along the roasting chamber wall 31, the distance corresponding to approximately a third of the height of the roasting chamber 12.

Inside the roasting chamber 12, six paddles 13 rotate around a center. Any number of paddles 13 could be utilized, however, between four and eight are usually preferred for the size of roasting chamber described herein. The paddles 13 protrude in a radial direction from the center, and are equally distributed around the center. The blades of the paddles 13 are planar, i.e. the face of the blade provided to shovel the coffee beans is flat and is aligned such that a normal to the blade face coincides with the direction of movement of the blade. This is clearly shown in figure 2, where the paddles 13 are seen from the side. Because the blades of the paddles 13 are flat and a plane of the blade is aligned perpendicular to the direction of movement, they will not shift the coffee beans in one particular direction other than that of the direction of rotation (i.e. the coffee beans will not be significantly shifted in a direction along the depth of the roasting chamber 12), and the coffee beans are evenly distributed along the depth of the roasting chamber 12 during roasting. The depth is in figure 2 defined as the direction into the viewing plane of the figure (perpendicular to the viewing plane). A continuous and even movement of the coffee beans inside the roasting chamber 12 is important in order to gain a homogenous roast, and avoid too much heat on some beans, and too little on others.

The motor which drives the paddles 13 is mounted on the outside of the chamber 12. The paddles 13 are shaped like a "T", better illustrated in figure 3 and 4, and rotate about the center in a clockwise direction as seen from the front in figure 2. The "T"-shaped paddles allow e.g. the sampler (not shown in figure 5, see figure 1) to be inserted into the roasting chamber without obstructing the paddles 13, and also allow temperature sensors 32,33 to protrude into the roasting chamber 12.

A heating element 14 is located in a lower portion of the coffee roaster 1 and heats air which is led through an inlet channel 15 along the path of arrow B in figure 1. The heating element 14 is elongate and extends along the depth of the roasting chamber 12 in order to provide an as homogenous heating of the coffee beans as possible, as the coffee beans are evenly distributed along the depth of the roasting chamber 12. The heating element 14 thus heats air along the entire depth of the roasting chamber 12. The heating element 14 is preferably a gas heater, but could also be an electrical heating element, or any other heating element known in the art. When the temperature is adjusted by e.g. the rotary knob 10, as explained previously with reference to figure 1, it is typically the amount of gas provided to the gas heater which is adjusted.

The hot air from the heating element 14 is led through a channel 15 along a path indicated by the dotted arrow B in figure 2. The air inlet channel 15 has a depth corresponding to the depth of the roasting chamber 12. A part of the wall in a bend along the channel 15 is a flat portion provided with prongs 16, through which parts of the hot air can pass on its way through the bend to the roasting chamber 12. Hot air can contain portions of air of varying temperature, and such temperature differences are undesirable in order to be able to control the roasting process as precisely as possible. The prongs 16 disrupt the stream of hot air emanating from the heating element 14 as it passes the bend, providing a more homogenous flow of hot air into the roasting chamber 12. The prongs 16 are provided along the entire depth of the air inlet channel 15, and these prongs 16 are more clearly illustrated in figure 4.

A gird pattern 17 is provided in the roasting chamber wall 31 where the hot air channel 15 meets the roasting chamber 12. The hot air generated from the heating element 14 must therefore pass the grid pattern 17 on its way into the roasting chamber 12. The grid pattern 17 is distributed along the entire depth of the roasting chamber 12 and roasting chamber wall 31, and comprises several hexagonal shaped openings forming a honeycomb pattemed grid. A patterned grid will also contribute to a more homogenous flow of hot air, and prevents the coffee beans from entering the air inlet channel 15.

As mentioned with reference to figure 1, the majority of the coffee beans will primarily be located in the lower, left quarter of the roasting chamber 12 during roasting, as gravity makes them settle in the lower part of the roasting chamber 12, and the clockwise rotation of the paddles 13 will shift the majority of the coffee beans to the left side of the roasting chamber 12. As previously explained, the coffee beans are evenly distributed along the depth of the roasting chamber 12. A skilled person understands that the number of coffee beans, the speed of rotation of the paddles 13, etc. will affect where the majority of coffee beans are located at a given time, but given a constant speed and suitable amount of coffee beans, the location of the majority of coffee beans is predictable. A suitable amount of coffee beans for the coffee roaster 1 is 100 grams. 100 grams off coffee beans is approximately equivalent to a volume corresponding to a third of the volume of the roasting chamber 12. A smaller amount of coffee beans is also possible, and a coffee roaster based on the same principles as those described here could even be designed for coffee bean batches of up to 500 grams or even 1000 grams.

The air inlet channel 15 directs the hot air into the roasting chamber 12, providing a directed flow of hot air generally upwards and to the left in figure 2, i.e. along the location where the majority of coffee beans are located during roasting of a suitable amount of beans. The air inlet channel 15 and grid pattern 17 is preferably located in the vicinity of where the majority of coffee beans are located, i.e. in figure 2 the grid pattern 17 is located in the lower, right quadrant of the roasting chamber 12, which is just to the right of the location of the majority of coffee beans. The hot air flowing from the hot air channel 15 thus enters the roasting chamber 12 next to where the majority of beans are located when the paddles 13 are rotating.

The rotating paddles 13 contribute to mixing the hot air with the coffee beans inside the roasting chamber 12, and as some of the coffee beans are lifted upwards by the paddles 13, they will eventually fall off the paddles 13 and try to settle in the lower part of the roasting chamber 12. While moving downwards, the coffee beans have a direction of movement generally opposite of that of the hot air flowing from the inlet channel 15 towards the exit channel 19. Such constant movement of coffee beans towards the hot air flow contributes to a very effective roasting process.

A bean temperature sensor 32 is provided on the back wall of the roasting chamber 12, and protrudes into the space of the roasting chamber 12. The back wall portion is visible in figure 2; the front wall is removed for visual purposes. The bean temperature sensor could also be provided in the front wall of the roasting chamber. As the temperature sensor is located in the lower, left quarter of the roasting chamber 12, the temperature sensor protrudes into the roasting chamber 12 where the majority of coffee beans are located during roasting. As the coffee beans encloses and covers the bean temperature sensor 32, it will not be affected much by the hot air entering the roasting chamber 12 from the inlet channel 15, and as the coffee beans are distributed equally along the depth of the roasting chamber 12, the bean temperature sensor 32 registers the bean mass temperature. As the coffee roaster 1 is able to register the temperature of the coffee beans accurately, the coffee roaster can automatically control and follow a predetermined temperature curve of the coffee beans, without taking into account the size and density of the coffee beans, the coffee bean moisture content, etc. Different batches of coffee beans can thus be assigned identical roasting profiles, providing a very consistent roast and predictable result.

An environmental temperature sensor 33, also known as an ambient temperature sensor, is provided in the back wall of the roasting chamber 12, and protrudes into the space of the roasting chamber 12. The environmental temperature sensor could also be provided in the front wall of the roasting chamber. The environmental temperature sensor 33 is located in the upper part of the roasting chamber 12, and is positioned above the location of the majority of coffee beans during roasting. The environmental temperature sensor 33 is positioned in between the hot air inlet channel 15 and the air exit channel 19, such that an ambient temperature of the roasting chamber 12 is measured. An environmental temperature sensor could basically be provided anywhere in the roasting chamber 12 where beans are not present during roasting.

The following description relates to figure 2 and figure 3. The coffee roaster 1 in figure 3 is in an open state, i.e. the side wall portion 18 is in an open state. As the coffee beans are roasted in the roasting chamber 12, exhaust gas, i.e. excess hot air and residue from the coffee beans, such as chaff, can escape through the exit channel 19. The exit channel 19 is partlyformed by the side wall portion 18 and the underside of the inlet lid 3, and continues above the roasting chamber 12. The exhaust gas continues through the exit channel 19 and is sucked into a cyclone, as described more in detail with reference to figure 5. During roasting, the inlet lid 3 should be installed in the coffee roaster 1, as illustrated in figure 2, in order to prevent air from the outside of the coffee roaster 1 to be sucked into the exit channel 19 through the inlet opening 2.

In order to easily discharge the coffee beans from the roasting chamber 12, a user may move the discharge handle 8 along the are shaped slot 9 (not illustrated in

figure 2 or figure 3, see figure 1). An arcuate movement of the discharge handle 8 in the are shaped slot 9 is actually a rotation in an anti-clockwise direction about a first rotational shaft 21, which causes the first rotary element 20 to also rotate in an anti-clockwise direction about the first rotational shaft 21. The first rotational shaft 21 is supported between two walls referred to as a front and a back wall, of which the front wall is the front panel which is not visible in figure 2 or figure 3.

Altematively, the user may simply input a command on the display (not illustrated in figure 2 or figure 3, see figure 1), and a motor can rotate the first rotary element 20. The motor can also be automatically activated, as part of an automatic roasting process. The user can therefore choose to either manually discharge the coffee beans, or let the coffee roaster 1 decide when it is time to discharge the beans. The coffee roaster 1 could for instance be set to discharge the beans when the temperature of the coffee beans have reached a predetermined temperature, or when the temperature of the coffee beans have had a predetermined temperature for a predetermined amount of time, etc. The discharge mechanism could also be activated by sound, i.e. in relation to first crack, which occurs when the coffee beans crack open. The sound of first crack is clearly recognizable, and is a clear indicator of where the coffee beans are in the roasting process. The coffee roaster 12 can recognize the distinct sound of first crack, and could e.g. be set to discharge the coffee beans from the roasting chamber 12 at first crack, or at a set time after first crack. The discharge mechanism can also be automatically activated based on a time setting.

During the anti-clockwise rotation of the first rotary element 20, an abutment shaft 36 connected to the discharge handle 8 and first rotary element 20 abuts an extended portion 22 of a second rotary element 23. The abutment shaft 36 is more clearly visible in figure 4. The extended portion 22 is rigidly connected to the second rotary element 23, causing the second rotary element 23 to rotate in a clockwise direction about a second rotational shaft 24. The second rotational shaft 24 is also supported between the front and back walls, of which the front wall is not visible in figure 2 or figure 3. The second rotary element 23 is rigidly connected to the side wall portion 18, and these two elements will thus simultaneously rotate about the second rotational shaft 24. The side wall portion 18 comprises on its lower end a circular wall portion 25 which is part of the circular wall that partly surrounds the roasting chamber 12, this is more clearly illustrated in figure 3. Thus, when the side wall portion 18 is rotated in a clockwise direction about the second rotational shaft 24, an opening in the roasting chamber wall is formed, and the coffee beans can be discharged through the opening. As described with reference to figure 2, the joint between the roasting chamber wall 31 and side wall portion 18 is positioned a distance up from the lowest part of the roasting chamber 12, the distance approximately corresponding to a third of the height of the roasting chamber 12. The continuous rotation of the paddles 13 thus contributes to discharge all the beans from the roasting chamber 12.

To close the roasting chamber 12, the discharge handle 8 can be moved in an opposite, arcuate direction in the are shaped slot 9, causing the first rotational element 21 to rotate in a clockwise direction and abut the side wall portion 18, causing the second rotary element 23 and side wall portion 18 to rotate in an anti-clockwise direction about the second rotational shaft 24 until the side wall portion 18 abuts the corresponding wall portion of the roasting chamber 12. Alternatively, the first rotational element 21 can be activated and rotated by the electric motor, either automatically triggered as part of an automatic roasting process, or by input on the display (not illustrated in figure 2 or 3, see figure 1).

In figure 4, the front, top and side panels of the coffee roaster 1 are removed for illustrating purposes, and the following elements from the above description are clearly shown: side wall portion 18 with circular wall portion 25; first and second rotary elements 20,23; first and second rotational shafts 21,24; and the extended portion 22. The prongs 16 of the air inlet channel 15 are also more clearly shown, and the grid pattern 17 where the inlet channel 15 meets the roasting chamber 12.

A cooling fan 26 is mounted on the back of the coffee roaster 1 and cools the interior of the coffee roaster 1 upon activation. Hot air is ventilated out from the interior of the coffee roaster, and cool air can enter, as is commonly known in the art. Also partly visible in figure 4 is the cyclone 27, into which hot air and chaff is flowed through the exit channel 19. In the cyclone 27 the chaff is separated; this is described more in detail with reference to figure 5.

The bean cooling fan 34 is shown below the tray 7. This cooling fan is activated either manually through the display, or automatically as part of the roasting process. The bean cooling fan 34 sucks air through the perforated base of the tray 7, and thus cools the beans located in the tray 7. The air is led through the coffee roaster 1 by a bean cooling duct 35, and is exhausted on the back of the coffee roaster 1.

Figure 5 is a cross section view of the coffee roaster, and the air exit channel 19 and cyclone 27 is shown. The cross section view shows the motor 28 which propels the fan blades 29 such that the air and chaff is sucked from the roasting chamber through the air exit channel 19 into the cyclone 27. Inside the cyclone 27, the chaff is separated along the inside walls of the cyclone 27, and is collected in a container 30 positioned below the cyclone 27. Such a way of separating particles from air is known in the art, and need not be described further. If it needs to be emptied, the container 30 can be pulled out from the front side of the coffee roaster 1 (to the left in figure 5), and inserted into the coffee roaster 1 by pushing it back into the apparatus.

While the invention has been described with reference to the embodiment(s) mentioned above, and especially related to coffee beans, it is to be understood that modifications and variations can be made without departing from the scope of the present invention, and such modifications and variations shall remain within the field and scope of the invention. Other products which could be roasted in the roasting device may include seeds, different types of beans, etc.

Claims (13)

1. A sample coffee roasting device (1), comprising: a roasting chamber (12) arranged to hold a sample of coffee beans; a heating element (14); an air inlet channel (15) configured to guide heated air from the heating element (14) into the roasting chamber (12); paddles (13) rotatable about a center, for continuous shifting of the coffee beans inside the roasting chamber (12), the paddles (13) comprising blades; an air exit channel (19), for exhausting air and residue from the roasting chamber (12); wherein the sample coffee roasting device (1) ischaracterized bya first temperature sensor (32) arranged to measure a temperature of the sample of coffee beans, the first temperature sensor (32) protruding into the roasting chamber (12) and configured for being covered by the coffee beans located in a lower part of the roasting chamber (12); the blades of the paddles (13) are planar and aligned perpendicular to the direction of movement, for evenly distribution of the coffee beans inside the roasting chamber (12).

2. The sample coffee roasting device (1) according to claim 1, further comprising a discharge mechanism, configured to discharge the coffee beans from the roasting chamber (12).

3. The sample coffee roasting device (1) according to claim 2, where the discharge mechanism comprises a side wall portion (18) configured to move relative to the roasting chamber (12).

4. The sample coffee roasting device (1) according to claim 3, where the discharge mechanism further comprises first and second rotary elements (20, 23) configured to rotate the side wall portion (18) of the roasting chamber (12).

5. The sample coffee roasting device (1) according to claim 1, where a second temperature sensor (33) is located in the upper part of the roasting chamber (12), for measuring an environmental temperature.

6. The sample coffee roasting device (1) according to any one of the preceding claims, where the heating element (14) and the air inlet channel (15) extend along the depth of the roasting chamber (12).

7. The sample coffee roasting device (1) according to any one of the preceding claims, further comprising a container (7) with a perforated base configured for cooling the sample coffee beans.

8. The sample coffee roasting device (1) according to claim 7, where a fan (34) in the roasting device (1) provides a flow of air through the cooling container (7) and the coffee beans.

9. The sample coffee roasting device (1) according to any one of the preceding claims, where the air inlet channel (15) is located in a lower part of the roasting chamber (12).

10. The sample coffee roasting device (1) according to any one of the preceding claims, where the inlet channel (15) comprises prongs (16) provided to create a homogenous flow of hot air into the roasting chamber (12).

11. The sample coffee roasting device (1) according to any one of the preceding claims, where the air exit channel (19) is located in the roasting chamber (12) substantially opposite of the air inlet channel (15), for ensuring a steady flow of heated air through the roasting chamber (12).

12. The sample coffee roasting device (1) according to any one of the preceding claims, where the discharge mechanism is controllable by a user and by the roasting device (1), the roasting device (1) is provided to activate the discharging mechanism according to a predetermined setting.

13. The sample coffee roasting device (1) according to any one of the preceding claims, where the weight of the sample of coffee beans is 100 grams.