BACKGROUND

[0001] The subject matter of the invention is a technical system for the drive of a housing or of a feed table of a saw for cutting logs with a roller chain, which is cheaper and easier to use than the existing systems and, as a result, enables a higher speed of return movement of the feed table of the bandsaw for cutting logs due to the rigidity of the roller chain.

BRIEF SUMMARY OF THE INVENTION AND REUATED ART

[0002] The essence of the proposed invention lies in the fact that the drive of the housing 1 or of the feed table that is fixed to the housing 1 of the bandsaw is implemented via a drive with a drive chain wheel or a drive sprocket wheel or a drive sprocket 5 that is driven and braked via a shaft 5.1 by an electric motor with a reduction gear or geared electric motor 1R or an internal combustion motor or any other motor whose power can be partially fed from the power generated through the deceleration of the housing 1 via an electrical loop or disengageable flywheel and is thus partially and reversibly returned to the system through a special electrical system that converts the kinetic energy generated through the braking of the housing 1 into electrical energy and feeds it back to the process.

The drive chain wheel or drive sprocket wheel or drive sprocket 5 drives the roller chain 7, that is clamped onto the bandsaw housing at fixing positions or points 3 and 4.

In addition, the roller chain 7 can be optionally clamped onto the bandsaw base 2 through special springs 8 that absorb the impulse forces generated in the acceleration and deceleration of the housing 1 or feed table under load. The technical execution of the installation of the drive on the feed table and the clamping of the chain on the base 2 allows a very simple installation of the machine - in addition, the whole technical solution is much simpler as well.

A machine constructed in the proposed manner can also be installed on a softer base or a simpler and cheaper foundations due to its self-supporting construction.

Other manufacturers, or the current state of the art, use a drum with a wire rope mounted on concrete foundations in front of or after the saw as the drive for the working table or workbench, whereby the wire rope drives the working table, which may also be called: an undercarriage or feed table or housing.

The wire rope is fixed from one side to the feed table/housing, then it travels around the drum in front of the saw, while the return strand travels below the undercarriage to the opposite side around the second drum, and then it is again fixed to the feed table or housing on the opposite side.

Due to the return strand of the wire rope, the feed table or housing is set on foundations that are raised from the bottom level to provide clearance for the installation and stroke or travel of the wire rope.

These existing systems, i.e. the current state of the art, require strong, high foundations, which are also very costly.

For our proposed technical invention, only a flat concrete slab is required since the entire drive system is mounted on the feed table and the housing 1 or base 2, which allows very easy and quick assembly.

At the same time, we do not need particularly strong foundations, as the construction of the entire machine is self-supporting.

According to our proposed technical invention, the bandsaw construction is significantly cheaper and simpler with the following advantages: - Compared to the wire rope, the roller chain wears more slowly - the wire rope must be regularly adjusted and replaced, which is not required with the roller chain.

- The great rigidity of the roller chain or any other chain guided through links with constant graduation, enables the greater acceleration and speed of the housing 1 or the feed table compared to wire ropes, which are elastic. Of course, with an oversized wire rope, we can achieve the same speeds, but the price of such a system is uncompetitive on the market and greater power is required since such a wire rope needs to be wound onto a winding drum, in which case considerable power is required; this is not required in the case of a chain that is guided over chain wheels or sprockets and has no internal loss.

- The great rigidity of the chain ensures the very accurate positioning of the feed table as it does not stretch. Also, there is no slipping of the chain. Both are achieved by guiding the chain over chain wheels or sprockets, travelling through the chain links, preventing the slipping or sliding that is distinctive for wire ropes. Similar slipping as with wire ropes occurs with belt drives. Due to belt elasticity, constant slipping occurs affecting the gear or drive efficiency.

Due to the invention of the drive of the housing 1 or of the feed table via roller chain the costs of bandsaw construction are significantly reduced, such as the construction of particularly strong foundations for the winding drum that are required by the existing systems that drive the feed table via wire ropes, which are wound on a special winding drum that is firmly fixed to the saw foundation.

These existing systems also require much more space for the installation of the wire ropes and the winding drum on which the wire rope is wound.

With the introduction of the replacement of wire ropes and the so-called winding drums with a chain or roller chain 7, as described below, we eliminated the need for complex foundations and optimised the bandsaw construction, which uses much less space, particularly the bandsaw height can thus be significantly lower.

Since the existing systems use wire ropes that are wound on the drum or winding drum, they must be elastic, which is a problem for fast movements of the housing (1) or the feed table because wire ropes elastically extend and plastic deformations also partially occur due to the large displacement forces, which entails the regular servicing or adjustments of the wire ropes. Due to the fact that the wire ropes are generally much more elastic than the roller chain 7, whose movement is defined by the division of the links 7.C, the roller chain 7 can be burdened to a much greater level, whereby higher speeds of the housing 1 or the feed table under load are achieved according to the following formula: F = m x a (force equals the product of mass and acceleration)

At the same time, due to the introduction of this technical invention, it is possible to move the housing 1 or feed table of the bandsaw using reactive movement with extremely high accelerations and consequently high speeds, which means that the working efficiency of the bandsaw is improved or the log cutting capacity is increased.

In addition, due to the accumulation of the braking energy or the consumption of this part of the energy to power other consumers of the bandsaw or machines in the surrounding area, we greatly improve the efficiency of the bandsaw's electrical energy, which also reduces the carbon footprint and contributes to the increased competitiveness of such a bandsaw compared to the existing bandsaw systems.

The current state of the art is such that bandsaw feed tables are guided using wire ropes driven by a pulley clamped to a reduction gear that is driven by an electric motor. The wire ropes are not clamped onto the housing through springs, but are rigidly coupled to the housing.

The current state of the art of bandsaws for cutting logs does not use electric motors to brake the feed tables, and consequently also does not conserve or convert the braking energy of the housings 1 or feed tables into active energy — reversible energy to drive other systems.

To stop feed tables, the current state of the art uses systems that discard the kinetic energy of stopping the feed tables with logs into the surroundings as heat energy or active energy or energy for work that is reflected as wear of the brake systems and are therefore energy- wasteful.

Due to the rigidity of the wire ropes and the relatively heavy feed table on which logs are prepared for cutting, it is extremely difficult to achieve higher speeds of the feed table’s reactive movement because due to the acceleration/deceleration (F = m x a), extremely high shock forces F are generated in the wire rope and drive. In the current systems, the braking energy of the housing 1 or the feed table with logs is a loss of energy from the entire machine or bandsaw.

The problem that is solved with the described invention is that the substantially higher reactive movement speeds of the housing 1 or working table or workbench can be used, since the roller chain 7 is able to withstand significantly higher forces than the wire rope, and additionally the roller chain 7 is guided via the drive chain wheel or drive sprocket wheel or drive sprocket 5 of the electric motor with a reduction gear or geared electric motor 1R and therefore roller chain 7 slipping cannot occur and consequently neither can an incorrect stroke of the housing 1 or the feed table.

The kinetic energy generated during the braking of the housing 1 is absorbed and converted into electrical energy by the electric motor with a reduction gear or geared electric motor 1R, which is controlled as an alternator or dynamo when braking, and the energy is recovered to the system and used to drive other consumers, in particular to drive the electric motor of the bandsaw blade.

This significantly improves the efficiency of the bandsaw in terms of electrical energy, while at the same time achieving significantly higher deceleration of the feed table with logs.

The power of the electric motor with a reduction gear or geared electric motor 1R to drive the housing 1 or the feed table is, of course, limited and can only convert a certain amount (impulse) of kinetic energy and, therefore, in certain systems, the entire drive can be upgraded with special springs 8 fitted onto the fixing areas or fixing positions or fixing points or fixture points or base fixtures or base mounts of the roller chain 3 and 4 of the roller chain 7 on the machine base 2.

Due to the additionally integrated springs on the fixture points of the roller chain to the saw housing, we are able to achieve even greater speeds of the feed table as the springs accumulate the impulses of the acceleration/deceleration force, releasing this energy during the movement of the working table or workbench.

In this way, a relatively stable force required for the feed table movements is obtained throughout the entire length of the stroke, and thus significantly reduced the loading of the drive train. [0003] As far as we know, such or a similar system is not used in this field.

In our review of the patent databases, we have found three patents with the determined keywords. However, they do not summarize the same technical inventions as our invention here presented.

Below, we describe the known state of the art (patents) and the differences between these and our proposed invention.

Patent No.: EP 06003663.9

Title: Metal bandsaw with suspended saw frame

This invention presents a technical invention of a saw band and does not describe the feed table drives.

This invention does not use the same or similar technical characteristics as our proposed invention.

Patent No.: 9110163

Title: Vertical bandsaw

This invention describes a technical mode of guiding the saw band and conveying the trimmings through the openings through which the saw band travels.

This invention does not have common technical solutions or similar technical solutions with our proposed system. As such, it is in no way similar to our proposed invention.

Patent No.: 21994 Title: Two-column bandsaw

This invention suggests a two-column bandsaw operation mode.

It does not provide any technical solutions for the feed trolleys drive or the like.

This invention also describes completely different technical solutions to our proposed invention, and as such provides no common technical solutions.

The above-mentioned patented technical inventions use completely different technical solution procedures, i.e. inventions, than our proposed invention.

The differences mainly lie in the principles of feed table drives.

All known systems that are partially similar to the proposed invention in this patent application use wire ropes for the feed table drive.

None of the known systems use an electric motor as a brake for the feed table or housing 1, and does not accumulate this energy or use it elsewhere.

All the known systems discard the braking energy of the feed table with logs as reactive energy into the surroundings or they use brakes that wear out and convert this energy into brake pad wear or similar.

In this way, this energy is lost and the systems are energy- wasting.

None of the known systems use a roller chain controlled through a chain wheel.

None of the known systems utilise springs to absorb the impulse and shock forces generated by starting and alternating the drive of the bandsaw feed tables.

Our proposed invention differs from the above-mentioned patented technical inventions in the fact that the drive of the feed table or the housing 1 is constructed via a drive chain wheel or drive sprocket wheel or drive sprocket 5 and a roller chain 7, which is secured on both sides to the base 2 of the bandsaw. This clamping can also be constructed via two springs 8, which both have the function of absorbing the impulse and shock forces F that are generated in the movements of the feed table or the housing 1 of the bandsaw.

An additional advantage of our proposed invention over the current state of the art lies in the fact that almost all braking energy can be recovered to the electrification process by converting kinetic energy into electrical energy in the electric motor with a reduction gear or geared electric motor 1R, which also acts as an alternator or dynamo, and use it for certain other systems or machines, in particular for driving the electric motor of a bandsaw blade.

This energy can also be partially accumulated through batteries, which may be electrical or executed, for example for pumping water to a higher level as used in hydro power plants that fill dams when they have excess of electrical energy.

As a result, we reduce the so-called “electrical peaks” when switching on the machines and consequently relieve the electricity network, which results in lower machine wattage and the associated lower costs of paying for a fixed part of the electric energy consumption.

If internal combustion engines or similar motors are used to drive, the braking energy is recovered via a large, disengageable flywheel, which can be mounted on the reduction gear unit or motor and switched on and off via a clutch.

This flywheel accumulates housing (1) decelerations.

The first advantage over the existing situation is that due to the use of the so-called shaped couplings between the drive chain wheel or drive sprocket wheel or drive sprocket 5 and the roller chain 7, we use significantly higher driving forces F to drive the housing 1, since the roller chain 7 is much more rigid than the wire rope; instead, a single -row or single- strand, double-row or double-strand or triple-row or triple-strand roller chain or a roller chain 7 with any number of rows or strands can be used.

In this case, the drive chain wheel 5 must have the same number of rows as the roller chain 7. The guide chain wheels or guiding chain wheels or guide sprocket wheels or guiding sprockets or guide sprockets 6 can also have fewer rows, but it is recommended that the number of rows is equal to that of the roller chain 7. When using a roller chain 7 with multiple rows, we do not increase the losses in the movements of the roller chain 7 via the chain wheels or sprockets, since it consists of moveable links 7.C, which allow it to freely move/break around the bolts of the roller chain 7, while in the existing systems, it is necessary to wind the wire rope around the drum, consuming energy to elastically twist the wire rope and resulting in a loss of energy.

In addition, with existing systems, multiple wire ropes cannot be used on a single drive, which implies a limitation on the capacity of the displacement force F of the housing 1 in a reactive stroke and consequently a limitation of the capacity of the bandsaw.

The higher drive force F enables a higher reactive stroke speed of the bandsaw housing 1, therefore improving the efficiency of the bandsaw and giving it a competitive advantage.

Another advantage over the current state lies in the fact that kinetic energy can be used to brake the housing 1 with logs, either by converting it to electrical energy in the electric motor with a reduction gear or geared electric motor 1R or by accumulating in the engageable flywheel when using other drive modes to drive other bandsaw systems, such as with the cutting blade drive, feed units drive etc.

Or we use this energy to drive other machines.

In this regard, the additional advantage is that the bandsaw wattage is reduced and the power supply is relieved, since the impulse peaks of the electrical energy are “cut”.

This part of the electrical energy can also be partially accumulated in batteries, which can be electrical or mechanical (pumping water to a higher level, increasing the pressure in pressure vessels, raising a load to a higher potential, etc. - this energy is conserved as potential or internal energy of the system and is used whenever we want). The described energy conversion is partially already part of the known state of the art, but we would like to emphasise that in our technical system, we convert almost all of the braking energy since the energy losses compared to the drive with the wire rope are significantly lower.

Below, the advantages of the roller chain 7 compared to the wire rope are described again, indicating the deficiencies of the wire rope as a housing 1 movement element:

- Compared to the wire rope, the roller chain wears more slowly - the wire rope must be regularly adjusted and replaced, which is not required with the roller chain. - The great rigidity of the roller chain or any other chain guided through links with constant graduation, enables the greater accelerations and speeds of the housing 1 or the feed table compared to wire ropes, which are elastic. Of course, with an oversized wire rope, we can achieve the same speeds, but the price of such a system is uncompetitive on the market and greater power is required since such a wire rope needs to be wound on a winding drum, which uses considerable power; this is not required in the case of a chain that is guided over sprockets and has no internal loss.

- The high rigidity of the chain ensures the very accurate positioning of the feed table or the housing (1) as it does not stretch. Also, there is no slipping of the chain. Both are achieved by guiding the chain over sprockets, travelling through the chain links, preventing the slipping or sliding that is typical of wire ropes. Similar slipping occurs with belt drives. Due to the belt elasticity, constant slipping occurs affecting the gear or drive efficiency.

The invention of the drive of the feed table or housing 1 via the roller chain 7 significantly lowers costs of bandsaw construction, such as the construction of the particularly strong winding drum foundations that are required by the existing systems that drive the feed table via wire ropes, which are wound on a special winding drum that is fixed to the saw foundation.

These existing systems also require much more space for the installation of wire ropes and a winding drum on which the wire rope is wound.

With the replacement of wire ropes and the winding drums with a chain or roller chain 7, as described below, we eliminated the need for complex foundations and optimised the bandsaw construction, which uses much less space, particularly the bandsaw height can thus be significantly lower.

Since the existing systems use wire ropes that are wound on the drum or winding drum, they must be elastic, which is a problem for fast movements of the feed table or housing (1) because wire ropes elastically extend and plastic deformations also partially occur due to the large displacement forces, which entails the regular servicing or adjustments of the wire ropes.

Due to the fact that the wire ropes are generally much more elastic than the roller chain 7, whose movement is defined by the division of the links 7.C, the roller chain 7 can be burdened to a much greater level, whereby, higher speeds of the feed table or housing 1 under load are achieved according to the following formula: F = m x a (force equals the product of mass and acceleration)

In the case of using a roller chain 7 with multiple rows or strands, we can accordingly increase the forces F of the displacements of the housing 1, thereby achieving even higher accelerations or reactive displacement speeds of housing 1.

At the same time, due to the introduction of this technical invention, it is possible to move the feed table or housing 1 of the bandsaw in reactive movement with extremely high forces F that generate strong accelerations and consequently high speed rates, which means that the working efficiency of the bandsaw is improved or the log cutting capacity is increased.

A further advantage over the current state of the art lies in the fact that with the use of optional springs 8, the forces F that occur during rapid movements of the housing 1 are significantly smaller.

The impulse or shock of the force F is taken over or absorbed by springs 8 and these distribute the force throughout the entire housing 1 movement, thus allowing a significantly less robust construction of the bandsaw because the acting forces F or their impulses, which could otherwise damage the bandsaw structure, are considerably smaller.

The impulses of forces F are generated during rapid reactive movements as the acceleration of the housing 1 and then as the deceleration of the housing 1 when we stop the housing 1 and prepare it for the next working movement.

The springs 8 also provide protection against overload of the feed force when cutting logs, which is transferred via housing 1, since they absorb the excess force that can accumulate in spring 8 according to the characteristics of the spring.

In this way, the saw band is protected against the overloading that could occur due to the improper setting of forces or the speed of the working stroke of the housing 1.

Due to the advantages described above over the existing technique in this field, the essential advantage of the proposed technical invention lies in the fact that the price of the bandsaw as a product and the costs of its operation and servicing, made in accordance with the proposed technical invention, are significantly cheaper than of the existing systems and can also be set up on a softer surface - that is, we need simpler and cheaper foundations and it is consequently easier to move to other locations.

DETAILED DESCRIPTION OF THE INVENTION AND BRIEF DESCRIPTION OF THE DRAWINGS

[0004] The described invention is further described in more detail with the description of the attached figures and with a technical description of the bandsaw drive train.

Figure 1: This shows a front view of a bandsaw drive train where are mainly visible the reduction gear unit 1R with the drive sprocket 5, roller chain 7, guide sprockets 6, housing 1, base mounts of the roller chain 3 and 4 and springs 8, that are not necessary but only optional, in particular in cases when insufficient wattage is available.

A method of controlling the feed table or housing 1 via wheels 1.1 on the base 2 can also be observed.

Figure 2: This shows the layout of Figure 1 where the reduction gear with the electric motor 1R is shown in detail, simultaneously serving as an electric brake (an alternator or a dynamo) and the mounting of the guide sprockets 6 via axis 6.1.

Visible is base 2 on which the housing 1 travels.

The described invention that is presented in this patent application enables very high speeds of the housing 1 or of the feed table to which the housing 1 is firmly fixed, whereby the energy consumption of the bandsaw is not increased since the energy of the braking/deceleration of the housing 1 is not lost, but can instead be used to power other systems or accumulate it in different ways, as has been described previously.

The high speed rates of the housing 1 during the so-called reactive movement are required in order to achieve the maximum efficiency of the log cutting time since the so-called reactive movement only entails a waste of time or is a working phase where we do not add value to the logs.

In order to achieve high speeds of the housing 1, we must increase the acceleration of the housing 1.

In order to achieve the fastest possible reactive/reversing movement of the housing 1, the deceleration of the housing 1 must be increased.

The acceleration and deceleration of the housing are related to the energy consumption, which is, in the present invention, maintained or converted via electric motor with a reduction gear or geared electric motor 1R, which acts as an electric motor or electric brake according to the principle of the alternator or dynamo that accelerates and later also decelerates the housing 1, etc.

The braking energy of the housing 1 that is absorbed or converted from kinetic to electrical by the electric motor with a reduction gear or geared electric motor 1R acting as an alternator or dynamo, is promptly used to drive other bandsaw electric motors, as well as the working motor to drive a saw blade or transferred to other consumers nearby.

We can also accumulate this energy in different ways, and later use it as previously described.

The fastest possible reactive movement of the housing 1 is necessary in order to carry out the next working stroke of the housing 1 or to carry out the next log cut.

In fact, at or during a reactive movement, we can adjust the transverse movement of the logs on the housing 1 or the transverse movement of the bandsaw to cut the next thickness of the logs. As a rule, the speeds of the working movements are conditioned by the technological parameters of the saw and logs, which is a known state of the art and is not the subject matter of this proposed invention.

Our proposed invention, due to the geared electric motor drive 1R via sprockets and the roller chain 7, ensures the use of extremely large forces F for accelerations and decelerations of the housing 1 with logs, while preventing drive elements from slipping as is the case in the current state of the art.

This is because the roller chain 7 is driven and stopped via the drive sprocket 5 and cannot slide over the drive sprocket 5.

As a rule, we use a roller chain 7 with multiple rows as this does not cause additional losses due to its displacement during the movements of the housing 1.

However, we ensure linearly higher drive loads to the extent of the number of rows of the roller chain 7 used.

At the same time, by increasing the accelerations and decelerations of the housing 1, we do not increase the consumption of electrical energy, since, as has been described on multiple occasions, it can be converted or transformed or accumulated via the geared electric motor 1R.

When using higher drive (acceleration or deceleration forces) forces, a spring 8 can be optionally added at the point of application of fixing points 3 and 4 of the roller chain 7, which absorbs the excess shock force F generated in the roller chain 7 due to the accelerations/decelerations of the housing 1.

The geared electric motor 1R would not be able to entirely convert or accumulate these excesses, but since this energy is returned by the spring 8 through the entire movement of the housing 1 in the form of kinetic energy that increases (in acceleration) or reduces (in braking) the speed of the housing 1, the geared electric motor 1R can convert or accumulate it as previously described.

Thus, both springs 8 absorb the shock forces F and in this way distribute the acceleration/deceleration of the housing 1 due to the tremendous forces F. Due to the absorption of the forces F with respect to the spring characteristic, the acceleration/deceleration is uniform throughout the movement of the housing 1.

In this way, we reduce the impulse or shock forces that would otherwise occur at the beginning of the movement and finally in stopping the movement.

The use of springs 8 can make the construction of the entire bandsaw easier because the springs 8 “cut” the impulses of the shock forces F and distribute this force over the entire stroke of the housing 1.

Although the electric motor with a reduction gear or geared electric motor 1R can take on great amounts of power and (in case of stopping/deceleration of the housing 1) can also transfer them to other consumers, particularly to the electric motor of the bandsaw blade drive, using the spring 8, which is optional, can relieve the impulses of the electric motor with a reduction gear or geared electric motor 1R and we can use a low -power electric motor 1R.

In this case, the electric motor with a reduction gear 1R takes over the housing 1 deceleration power over a longer time range, enabling the easier transfer of this part of the energy to, for example, the electric motor of the bandsaw blade drive.

The roller chain 7 is fixed to the base 2 of the bandsaw, which is idle or static during machine operation, on the left side of the base mount of the roller chain 3, and optionally also via spring 8.

Similarly, the roller chain 7 on the right side is fixed into the base mount of the roller chain 4, and can optionally also be fixed via the spring 8.

The spring 8, if optionally added, is fixed with an articulated joint to the left side via the link 8.1 to the roller chain 7, which travels via the left guide chain wheel or guiding chain wheel or guide sprocket wheel or guide sprocket 6 to the drive sprocket 5 and again via the right guide chain wheel or guide sprocket 6 to the link 8.1, to which it is fixed with an articulated joint, while link 8.1 is, however, fixed with an articulated joint to the right spring 8, if optionally added. In cases where spring 8 is not used, the roller chain 7 is fixed via the articulated joint 8.1 directly to the base 2 of the bandsaw, through the base fixings or base mounts of the roller chain 3 and 4 on the other side.

The drive chain wheel 5 is fixed to the shaft 5.1 of the reduction gear unit 1R and bears all the forces F for the housing 1 drives.

The shape of the tooth 5.Z of the drive sprocket 5 may be arbitrary, whereby it is important that it meets the mechanical requirements of transmitting the forces F from the drive sprocket 5 to the roller chain 7.

The shape and dimension of the links 7.C of the roller chain 7 is conditioned by the shape of the tooth 5.Z on the drive sprocket 5, and at the same time it must meet the mechanical requirements of transmitting the shock forces F from the drive sprocket 5 via the roller chain 7 and via the links 8.1, the springs 8 (if they are optionally additionally fitted) and the links 8.2 onto the base mount of the roller chain 3 and 4, respectively.

Links 8.2 are used when the springs 8 are added optionally.

If the optionally integrated springs 8 are not used, the roller chain 7 is fixed to the base mounts or base fixtures 3 and 4 only through links 8.1.

The springs 8 are used primarily in the case of very high electrical powers of the drives of the housings 1 and in the case of a smaller wattage available from the electricity network since the springs 8 help in the easier allocation/distribution of the impulse force of the acceleration or deceleration and therefore allow a more even distribution of the force and, consequently, the electric current of the electric motor 1R across the entire path of the housing 1.

The left and right spring 8, if optionally used, are clamped with the articulated joint to the base mounts of the roller chain 3 and 4, respectively, via links 8.2. Links 8.1 and 8.2 can only transmit tensile force F.

The drive train structure is constructed in such a way that the wrap angle a of the drive sprocket 5 and the roller chain 7 equals 60 to 120 degrees.

The guide sprockets 6 are freely mounted via the axis 6.1 on the housing 1. The housing 1 is part of the feed table with which the log is fed to the bandsaw, and after the cut is completed, a reactive stroke of the feed table or housing 1 is performed, and then the repeated working stroke for cutting the logs etc. is carried out.

The feed table is using a known method of attachment to the housing 1 and is not the subject matter of this invention; therefore, it is not specifically described in the description.

It is only mentioned for the sake of understanding the kinematics or functioning of the log feeding operation to the bandsaw blade via the housing 1.

Feeding is understood to include the working movement of the housing 1, in which the bandsaw cuts the logs and the reactive movement of the housing 1 in which the support 1 moves back as quickly as possible so that it can start the working movement as soon as possible.

All such movements of the housing 1 are in the direction SV left and right.

The housing 1 is fitted with freely mounted wheels 1.1 on the underside, which are driven on the base 2, which is a fixed and smooth plane.

It may additionally be upgraded with a vacuum cleaner to suck up any shavings from the base 2 in order to allow as little rolling resistance as possible for the wheels 1.1 and, consequently, to provide as much horizontal movement as possible of the housing 1 without lifting caused by foreign objects under the wheels 1.1.

In order to minimise the rolling resistance as much as possible, it is desirable that the wheels 1.1 should be as large in diameter, as smooth on its surface and as hard as possible.

It is similarly desirable that the surface of the base 2 should be as smooth and as hard as possible.

Description of the operation:

The log cutting work process does not require high feed working speeds in the direction SV.

After completing the work cut or log cutting in one direction, it is desirable to move the feed table or housing 1 to the starting position as soon as possible - the so-called reactive movement. The reactive movement means a loss of working time and it is important to keep it at a minimum or to perform it as fast as possible.

By using the above-presented invention, substantially shorter times of the so-called reactive movement of the housing 1 are achieved.

Assume, for example, that the working table or workbench that is secured to the housing 1 is in the left end position according to Figure 1.

To drive the feed table in the direction SV, to the right, an electric motor with a reduction gear 1R is powered in the direction SO to the so-called left-handed side.

Shaft 5.1 of the reduction gear unit 1R propels the drive chain wheel 5, rotating it left-handedly in the SO direction.

The drive sprocket 5 has teeth 5.Z built in that coincide with the division or shape of the links 7.C of the roller chain 7 and, with them, form the so-called non-slip shaped coupling.

For this reason, the drive sprocket 5 pulls the roller chain 7, that is clamped onto the right side via the link 8.1 and the optionally upgraded spring 8 and again via the link 8.2 to the base mount of the roller chain 4, to the left side.

The roller chain 7 runs over the guide sprocket 6, which is freely and pivotally mounted on the axis 6.1 and rotates it in the right-hand direction in the SO direction.

The guiding chain wheel or guide sprocket 6 has the function of guiding the roller chain 7.

The drive sprocket 5 pulls the roller chain 7 to the left, whereby a certain force F between the drive sprocket 5 and the base mount of the roller chain 4 is generated.

As a rule, force F is an impulse or shock force as we want to achieve the highest possible accelerations of the housing 1.

The spring 8, if optionally upgraded, on the right side, at the base mount of the roller chain, due to the shock force F, extends and absorbs the shock force F and distributes it over the entire duration that the force F is acting depending on its characteristics of the spring 8. Due to the force F, the housing 1 moves via wheels 1.1, which are driven on the base 2 to the right towards the base mount of the roller chain 4, in the SV direction, to the right side according to Figure 1.

When the initial extremely high acceleration and extremely high force F, which act due to the large mass of the housing 1 on which the cutting log is placed, decrease, the spring 8 (if optionally upgraded) shrinks proportionally and transmits the accumulated force F to the roller chain 7, and in this way, it maintains a fairly constant acceleration of the housing 1, almost throughout the movement in the SV direction.

If the optionally upgraded springs 8 are not used, the geared electric motor 1R directly absorbs the energy of acceleration or acceleration force, which through its control, provides the optimum acceleration according to the consumption of electrical energy or according to the set maximum current-peak load.

This method is only used for the so-called reactive movement, whereby we want to achieve the shortest possible time so that the housing 1 is ready as soon as possible for the so-called working movement in which the bandsaw performs the cutting of logs that are secured to the working table or workbench via the housing 1.

When the housing 1 or feed table reach the right end position at the base mount of the roller chain 4, it is previously stopped via the roller chain 7 by the drive sprocket 5, which is firmly fixed/mounted on the shaft 5.1 of the geared electric motor 1R, and the deceleration energy is absorbed by the geared electric motor 1R and transmits this energy to other consumers or transmits it to the batteries.

If the optionally upgraded springs 8 are not used, the acceleration and deceleration forces are absorbed directly by the geared electric motor 1R, which takes over the deceleration energy and converts it into driving energy of the electric motor of the bandsaw blade or other consumers, or accumulates this energy as described previously.

The geared electric motor 1R stops the housing 1 in a similar way that was previously used in its acceleration, whereby it now extends the spring 8 (if optionally upgraded) at the base mount of the roller chain 3 on the left side and, after reaching the end point of the housing 1, again shrinks to its initial position, thereby reducing the deceleration of the housing 1. If the optionally upgraded springs 8 are used, these are mounted via links 8.1 on both sides, on the roller chain 7 by means of an articulated joint, which means that the joint in link 8.1 can move freely.

Similarly, both springs 8 are clamped via links 8.2 with articulated joint to the base mount of the roller chain 3 for the left side and 4 for the right side according to Figure 1.

Links 8.1 and 8.2 can only bear tensile stresses of force F.

Likewise, but in reverse order, the movement of the housing 1 or the feed table to the left in the SV direction to the left takes place.

The roller chain 7 or the housing 1 drive is symmetrical, making it arbitrary in which direction the so-called reactive movement is made.