Replaceable working head of dyeing device for leather products and dyeing device with such working head

Abstract

The invention relates to a dyeing device for pieces of leather products, which comprises a replaceable working head and a drive unit for transmitting rotary motion to a dyeing shaft (2) provided in the working head, which is connected by a detachable coupling means to said drive unit. The dyeing device also has an adjustment system for adjusting the thickness of the dye layer.

Description

Technical field

[0001] The invention relates to devices for dyeing leather products, and more particularly to a dyeing device with a replaceable working head for parts of leather products, for example bags, encasers, suitcases and others. The invention is applicable in the field of leather goods.Prior art

[0002] Dyeing the edges of bags is one of the most difficult processes in the production of leather goods. The dyeing process is the application of a layer of dye to the edge of the finished product by a dye roller coated with a precise amount of dosed dye. The dye roller rotates at a certain speed and during this rotation and counter movement of the dyed object, the dye is transferred from the dye roller to the product being dyed. The main parameters and requirements for dyeing the edge of finished products are: thickness of the applied layer; number of applications that must be performed to reach the required quality; drying of the dye in the container of the dyeing device; obtaining an overedging during dyeing - this is the dye remaining on the face of the dyed product, and not only on the edge of the dyed product; speed of movement of the finished product when applying the dye; ability to quickly change colors.

[0003] When dyeing small pieces, this is done at stationary machines by applying a layer of dye to the edges of the pieces. Dyeing finished products is often difficult to do with stationary machines due to the fact that the finished products are large and difficult to hold which hinders their quality dyeing.

[0004] A hand device for dyeing leather products is known, comprising a housing in which a dyeing shaft, supported in the housing, and a drive electric motor connected by a coupling for transmitting rotary motion to the dyeing shaft are arranged, which electric motor has terminals for connection to a source of current and control unit. The devise also has a dye container with an upper dye opening for dye loading and a lower dye opening for feeding dye to the dyeing shaft. The container is mounted directly above the dyeing shaft, and the distance between the lower opening of the container and the dyeing shaft is constant, thus determining the thickness of the dye layer. Disadvantages of the known device are unevenness of the applied dye layer, impossibility of adjusting the thickness of the dye layer, drying of the dye in the container of the dyeing device, unwanted overedging, impossibility for quick change of the colors when dyeing, impossibility of dyeing with low viscosity dyes due to dye leaking from the container as a result of the gravitational pressure created by the vertical container placed on the dyeing shaft.Summary of the invention

[0005] An object of the invention is to create a replaceable working head for a dyeing device for leather products which provides circulation of the dye while preventing it from thickening or drying up and also having the ability for quick changing of dyes of different color.

[0006] Another object is to provide a hand dyeing device that is portable and convenient to work, and can serve the technological process of dyeing the edges of finished products.

[0007] An additional related object is that the hand dyeing device to provide full access to all parts of the product to be dyed and at the same time, the dyeing is of high quality with uniform application of the dye layer.

[0008] These objects are achieved by creation of a replaceable working head for a device for dyeing leather products, comprising a housing in which are arranged a dyeing shaft, resting in the housing, a coupling for connecting the dyeing shaft to a drive unit of the dyeing device for transmitting rotary motion to the dyeing shaft. The replaceable working head also comprises a dye container attached to the housing with the ability to feed dye to the dyeing shaft and mounting parts for a detachable connection of the working head to the drive unit of the dyeing device. According to the invention there is a central channel for dye in the dyeing shaft with dye inlet at one end and dye outlet at the other end. The dyeing shaft has, successively arranged, a dyeing section, ending with the dye outlet and located outside the housing of the replaceable working head, a pump section and a drive section connected to the coupling means. The pump section of the shaft is rotatably located in a sealed circulation cavity of the housing, which is hermetically isolated from the driving section of the shaft. On the pump section of the shaft, there are, arranged successively and immovably fixed, a first screw pump, an insulating ring dividing the circulation cavity into isolated first and second parts, and a second screw pump, located in the second part of the circulation cavity, the outlet end of which is connected to the dye inlet of the dyeing shaft, and the inlet end of which is connected to the dye inlet of the housing. The first part of the circulation cavity ends on the side of the working section of the shaft with a bearing sleeve hermetically connected to the housing in which the dyeing shaft rests, which bearing sleeve has a through hole for receiving the excess dye from the working section of the shaft, which hole is connected to dye cavity in the sleeve. This dye cavity is part of the first part of the circulation cavity of the housing, in which the first screw pump is located, which extends to the dye outlet of the housing. The dye outlet and dye inlet of the housing are connected, respectively, through dye inlet and outlet pipes, to dye container.

[0009] The device also has an adjustment system for adjusting the thickness of the dye layer, comprising an adjustment plate for the thickness of the dye layer, located parallel to the working section of the shaft, and mounted to the housing of the replaceable working head by an adjusting means with the ability to adjust the width of a gap between the dyeing shaft and edge of the adjustment plate.

[0010] In a preferred embodiment of the invention the coupling means is a part of a two parts coupling designed to transmit contactless rotary motion from an electric motor of the dyeing device to the dyeing shaft, wherein said coupling means is a magnetic element mounted on the drive section of the dyeing shaft with the ability of free rotation in the working head housing.

[0011] In one embodiment of the invention, the first screw pump, the insulating ring and the second screw pump are made as one monolithic piece.

[0012] In a preferred embodiment of the invention, the adjustment system for the thickness of the dye layer comprises an adjustment element with elongated housing with a longitudinal groove, one side of the groove being formed by the adjustment plate, and the elongated housing is located next to and parallel to the axis of the dyeing shaft and encases it at least partially. The working section of the dyeing shaft is rotatably located in the longitudinal groove of the adjustment element, so that a temporary reservoir is formed between the walls of the groove and the dyeing shaft for distributing dye on the working section of the dyeing shaft, which temporary reservoir at its one end is connected to the dye outlet of the dyeing shaft. The adjustment element is connected to the housing of the working head of the housing by means of an arm of a rotating holder, mounted to the housing of the working head by means of an adjustment shaft, resting by bearings in the housing of the working head with the ability of rotation around an axis parallel to the rotation axis of the dyeing shaft. The angle of rotation of the adjustment shaft is mechanically controlled by an adjustment handle. The rotating holder with the adjustment shaft, together with the adjustment element, are configured for simultaneous interdependent rotation, adjusting the width of the gap between the adjusting plate and the dyeing shaft.

[0013] In one embodiment of the invention, the dye layer thickness adjustment system is configured to adjust the layer thickness in 70 micron increments.

[0014] The objective is also completed by creating a device for dyeing of leather products comprising a working head with a dyeing shaft, drive unit with an electric motor which has terminals for connection to a source of current and a control unit and a connector configurated to transfer rotational movement from the mentioned electrical motor to the dyeing shaft of the working head. According to the invention, the working head is a replaceable working head as is described in claims 1 through 5, wherein the replaceable working head is hermetically isolated from the drive unit and has mounting parts for releasable connection of the housing of the replaceable working head to the drive unit in the connection area of the dyeing shaft and the electrical motor. The mentioned connector is releasable and includes two separate parts, where the first part is mounted to the driving section of the dyeing shaft with the possibility of free rotation inside the housing of the working head and the second part of the connector is connected to a shaft of the electrical motor in the drive unit. Preferably, the coupling is a two-part magnetic coupling, and is designed to transmit the rotary motion from the electric motor to the dyeing shaft without contact, wherein the first part of the magnetic coupling is mounted on the drive section of the dyeing shaft with the ability of free rotation in the housing of the replaceable working head, and the second part of the magnetic coupling is connected by a mechanical coupling to the shaft of the electric motor, which mechanical coupling is accommodated in bearings with the ability of free rotation relative to the housing of the drive unit and together with the second part of the magnetic coupling.

[0015] Preferably, the mechanical coupling is a fork coupling.

[0016] Preferably, a mechanical locking means is provided for fixing the housing of the working head to the drive unit of the dyeing device in assembled state.

[0017] In a preferred embodiment the dyeing device is configurated as a mobile dyeing device, wherein the drive unit with the electrical motor is formed as a handle of the dyeing device.

[0018] The advantages of the replaceable working head of the dyeing device for leather products according to the invention are: A constructive separation and releasable connection of the working head and the drive unit provides for easy replacement of one working head with a particular color with a working head with a different color. This allows for fast and comfortable replacement of the color of dye in the working process without the need for change of the container and washing of the entire working head. The circulation of dye, through returning of the excess paint in the dye container as well as the hermetic working head through which the dye circulates both prevent the dye from drying and minimizes losses when dyeing. The regulatory system for regulating the thickness of the dye layer, allows for an even application of a dye layer and choosing the thickness.

[0019] The advantages of the hand dyeing device according to the invention are: The compact hand device is mobile and allows for easy dyeing of leather products. The design of the replaceable working head allows the mobile device to work both in a horizontal position of the dyeing shaft and at different angles, including vertical dyeing shaft, when the front part of the dyeing shaft, where the dye outlet is located, is directed upwards, due to the continuous circulation of the dye and sufficient pressure created by the pump. The dyeing device can also operate at an angle of the dyeing shaft of up to about 45 degrees without dripping dye when the front of the shaft is pointing down, due again to dye circulation. Description of the attached figures

[0020] The invention is explained in more detail through preferred embodiments, given as non-limiting the scope of the invention examples, with reference to the attached figures, where: Figure 1 is an axonometric side view of the device for dyeing leather products, according to a preferred embodiment of the invention. Figure 2 is a top view of the mobile device for dyeing leather products, according to a preferred embodiment of the invention as a mobile device. Figure 3 is a longitudinal section along line A-A, of the mobile device for dyeing leather products, according to a preferred embodiment of the invention shown in Figure 1. Figure 4 is a longitudinal section of the device for dyeing leather products, according to a preferred embodiment of the invention, and a partial view of the working head of the device of said longitudinal section. Figure 5 is a schematic view of the mobile device for dyeing leather products, according to a preferred embodiment of the invention, with highlighted dyeing shaft with first screw pump, insulating ring, second screw pump and second part of the magnetic coupling attached thereto. Figure 6 is a schematic view of the mobile device for dyeing leather products, according to a preferred embodiment of the invention, with highlighted electric motor, mechanical coupling and first part of the magnetic coupling in the drive unit. Figure 7 is a schematic view of the mobile device for dyeing leather products, according to a preferred embodiment of the invention, with highlighted, successively arranged, first screw pump, insulating ring, magnetic coupling, mechanical coupling, and electric motor. Figure 8 shows a longitudinal vertical section of an adjustment system for adjusting the thickness of the dye layer, according to a preferred embodiment of the invention. Figure 9 shows a longitudinal horizontal section of the adjustment system for adjusting the thickness of the dye layer, according to the preferred embodiment of the invention shown in Figure 8. Figure 10 is a vertical cross-section of the adjustment system for adjusting the thickness of the dye layer, according to the preferred embodiment of the invention shown in Figures 8 and 9. Exemplary embodiment of the invention

[0021] The replaceable working head of the device for dyeing leather products, according to a non-limiting embodiment of the invention shown in the figures, comprises a housing in which a dyeing shaft 2, resting in bearings in the housing, and a coupling which transmits rotary motion from the drive electrical motor 22 to the dyeing shaft 2 are arranged. A dye container 7 is attached to the housing, the outlet of which is connected to a dye inlet in the housing. The dye container 7 is attached to the housing, for example, with a tight connection through an O-ring or in another suitable way, and the dye is fed from the container to the dyeing shaft 2. The container can have hard walls or it can be a replaceable soft-walled bag pre-filled with dye. The container 7 can have an upper dye filling opening and at least one lower dye outlet opening.

[0022] There is a central dye channel 1 in the dyeing shaft 2 with dye inlet 14 at one end and dye outlet at the other end.

[0023] Preferably, the dyeing shaft 2 is made of a material with high wear resistance, for example stainless steel, which is preferably nitrogenized or having a special coating for wear resistance.

[0024] The dyeing shaft 2 has, successively arranged, dyeing section, ending with the dye outlet and located outside the housing of the working head, pump section and drive section connected to the coupling. The dyeing shaft 2 rests in bearings in the housing of the working head, preferably in two places, as shown in the figures in the front part of the pump section and in the rear part of the drive section. The pump section of the dyeing shaft 2 is rotatably located in a sealed circulation cavity of the housing having cylindrical form. On the pump section of the shaft 2, there are successively arranged and immovably fixed (Fig. 4) so that they rotate together with the dyeing shaft 2, a first screw pump 9, an insulating ring 11, dividing the circulation cavity into isolated first and second parts, and a second screw pump 13 located in the second part of the circulation cavity, the outlet end of which is connected to the dye inlet 14 of the dyeing shaft, and the inlet end of which is connected to the dye inlet 12 of the housing. Thus, through a system of channels and openings, the movement of the dye from the dye container 7 to the working section of the dyeing shaft 2, and the return of unused dye from the dyeing shaft 2 to the dye container 7, are ensured. The insulating ring 9 is of such diameter that it can rotate freely in the circulation cavity of the housing and, at the same time, provide minimum technological clearance between the peripheral surface of the insulating ring 9 and the inner cylindrical surface of the circulation cavity.

[0025] The first part of the circulation cavity ends on the side of the working section of the dyeing shaft 2 with a bearing sleeve 4, hermetically connected to the housing at the wet part, in which bearing sleeve 4 the dyeing shaft 2 rests. Preferably, the bearing sleeve is made of technical plastic with high wear-resistant properties. Preferably, the bearing sleeve 4 is a sliding bearing element designed as a semi-open bearing. The bearing sleeve also has a through hole, which receives the excess dye from the working section of the shaft 2, which hole is connected to a dye cavity in the sleeve 4, which cavity is a part of the first part of the circulation cavity of the housing, in which the first screw pump 9 is located, and which extends to a dye outlet 10 in the housing. The first screw pump 9 sucks the excess dye that enters the first part of the circulation cavity through the hole in the bearing sleeve 4, and transports it to the dye outlet 10 in the housing, which is connected to the dye container 7. Thus, the excess dye goes back to the container.

[0026] The first screw pump 9, the insulating ring 11 and the second screw pump 13 can be made as one monolithic piece, or alternatively be separate pieces which are connected to each other and are preferably made of technical plastic. It is also possible that the first screw pump 9, the insulating ring 11, the second screw pump 13, and the coupling housing are made as one monolithic piece, as shown in Figures 5, 6 and 7. They are preferably made of high resistance technical plastic.

[0027] The dye outlet 10 and dye inlet 12 of the housing are connected, respectively, through dye inlet and outlet pipes, to the dye container 7.

[0028] The speed of rotation of the dyeing shaft also determines the amount of dye, which is supplied by the second screw pump 13 to the front part of the shaft 2 through the dye channel 1. Higher rotation speed of the electric motor 22 causes faster rotation of the dyeing shaft 2 together with the screw pumps, and, accordingly, more dye is pumped from the container and forced by the second screw pump 13 into the dye channel 1 of the dyeing shaft 2. Thus, through the control buttons 23 of the control unit 20, which controls the revolutions of the electric motor 22, the operator increases or decreases the amount of dye supplied to the working section of the dyeing shaft 2 depending on the need. For example, when dyeing wider edges, a larger amount of dye is needed to achieve the specified thickness of the dye layer. The selected speed is shown on the display 21 of the control unit 20.

[0029] The dyeing device, according to the invention, has two parts that are hermetically isolated from each other - a replaceable working head (wet part), in which the dyeing shaft 2 is located, and a drive unit (dry part), in which the electric motor 22 is located. The two parts of the device are releasably connected to each other in the area of the connector between the dyeing shaft 2 and the electrical motor 22. The working head is hermetically isolated from the drive unit. This way the electrical motor 22 is protected from the dye while the whole inner system of cavities of the working head is isolated from the outside air which prevents the circulating dye from drying.

[0030] The dyeing device for leather products also comprises a mechanical locking component for fixing of the working head to the drive unit in an assembled state, which can be, for example, a bayonet connection, or a spring-loaded pin and corresponding groove, or other appropriate means known from the state of the art.

[0031] The electric motor 22 has terminals for connection to a current source, which can be a battery mounted to or in the drive unit, or it can be in a separate power unit outside the drive unit that is wired, via a cable, to the electric motor. Alternatively, the power supply can be external, via a cable, for example, via a USB cable, with a plug, from a central power supply network. In the variants with external power supply (network or separate battery unit), when the dyeing device is a mobile device, it is lightened, and it is more convenient to work, as it tires less the hands of the operator who holds it.

[0032] The electric motor 22 also has terminals for connection to a control unit 20, which can be mounted to the housing of the drive unit (Figs. 1, 2, 3). Alternatively, the control unit 20 can be externally located and connected to the electric motor 22 by cable connection, thus also lightening the variant as a mobile device, and making it more convenient to operate, as it tires less the hands of the operator who holds it. For example, the control unit can be combined with an external battery unit. The control unit 20 serves to control the revolutions of the electric motor 11, and comprises, for example, a microprocessor controller with board 18, display 21 and control buttons 23 for increasing and decreasing the speed of the electric motor 22 (Fig. 2).

[0033] The electric motor 22 can also have a fan 25 for cooling the electric motor 22 located in the housing of the drive unit (Fig. 3).

[0034] In the stationary embodiment of the dyeing device the housing of the power unit is located on and preferably fixed, for example, to the working table or table top. In a preferred embodiment as a mobile device (shown on the figures) drive unit (dry part) in which the electric motor 22 is located and is shaped as a handle 24 of the device.

[0035] In the embodiment shown in the figures (Fig. 3), the housing of the drive unit has an openable rear cap 26 for access.

[0036] The coupling between the dyeing shaft 2 and the electric motor shaft 22 can be mechanical or magnetic, respectively, releasable or combined. In case of a magnetic coupling, it could be known straight or angled magnetic coupling. In the variant shown in the figures (Fig. 3, 6, 7), the coupling is combined and comprises releasable magnetic coupling connected to a non-releasable mechanical coupling 17 and has a housing, preferably made of technical plastic, to allow its operation. The releasable magnetic coupling is made of two parts 15, 16. The magnetic coupling transmits without contact the rotary motion from the electric motor 22 to the dyeing shaft 2, thus dividing the dyeing device into two parts - dry part in which the electrical modules are placed, and wet part where the dyeing takes place. Thanks to the magnetic coupling, it is extremely easy to separate the wet part (the working head) of the machine and clean it, because there are no electrical components in it. Also, in this way, the color used by the mobile device can be easily changed without the need to wash its wet part. This is possible because after the wet part is removed from the mobile device, another working head / wet part loaded with different dye color can be placed in its place and the work can be continued without having to wash the removed wet part. The removed working head with the old color can be placed on a support station that will keep it in working order so that the dye does not dry, while the work with the newly installed working head with the new color can continue. The number of colors, which can be worked with, is not limited as long as there are enough working heads for the device and enough support stations.

[0037] In the preferred embodiment shown in the figures, the two parts 15 and 16 of the releasable magnetic coupling are cylindrical, the first part 16 entering the second part 15 (Figs. 3, 7) which has a central cylindrical cavity. The first part 16 of the magnetic coupling is mounted on the drive section of the dyeing shaft 2 and is located in the circulation cavity in the working head so as to rotate freely in the working head. The second part 15 of the magnetic coupling is connected by a mechanical coupling 17 to a shaft of the electric motor 22, which mechanical coupling 17 is supported by a bearing 19 in the drive unit so that it rotates freely and together with the second part 15 of the magnetic coupling. The end of the housing of the working head, in which the first part 16 of the magnetic coupling is located, is preferably cylindrical and is made of such a diameter that it enters an open cylindrical cavity of the housing of the drive unit, around which the first part 16 of the magnetic coupling is resting. The magnetic field created by the first part 16 of the magnetic coupling passes through the walls of the two housings connected to each other and interacts with the magnetic field of the second part 15 of the magnetic coupling. During the rotation of the first part 16 of the magnetic coupling in the drive unit, the second part 15 of the magnetic coupling in the working head also rotates together with the dyeing shaft 2 and the screw pumps 9 and 11 arranged on it. This design allows non-contact transmission of the rotary motion from the electric motor to the dyeing shaft, wherein the two parts of the dyeing shaft are isolated from each other and at the same time, they are releasably connected to each other.

[0038] The mechanical coupling 17 transmits the rotation from the electric motor 22 to the first part 16 of the magnetic coupling, so as to protect the bearings 19 of the electric motor 22 from possible misalignments and vibrations, since there is a large clearance. The mechanical coupling 17 is, for example, a fork coupling, and consists of a male and a female part, which are mounted, respectively, on the shaft of the electric motor 22 and on the first part 16 of the magnetic coupling. Alternatively, another type of suitable coupling known in the art can be used.

[0039] The dyeing device also has an adjustment system for adjusting the thickness of the dye layer, comprising an adjustment plate for the thickness of the dye layer, located parallel to the working section of the dyeing shaft 2 and mounted to the housing of the replaceable working head by means of an adjustment means, so as to allow adjustment of the width of the gap between the dyeing shaft 2 and the edge of the adjustment plate. The adjustment of the thickness of the dye layer on the dyeing shaft 2 is done, respectively, by manipulation of the adjustment means, which moves away or closer to the dyeing shaft 2 the adjustment plate located parallel to it by rotation of the adjustment plate around the center of the dyeing shaft 2, or by progressive movement, tangentially moving the adjustment plate away from or closer to the dyeing shaft 2. In the embodiment shown in Figures 8 and 9, the adjustment system for the thickness of the dye layer comprises an adjustment element 3 with an elongated housing with a longitudinal groove, one edge of the groove being formed by the adjustment plate. The elongated housing is located next to and parallel to the axis of the dyeing shaft 2 and at least partially encases it. The working section of the dyeing shaft 2 is arranged to be able to rotate freely in the longitudinal groove of the adjustment element 3, so that a temporary reservoir is formed between the walls of the groove and the dyeing shaft 2 for distributing dye on the working section of the dyeing shaft 2. This temporary reservoir is connected to the dye outlet of channel 1 of the dyeing shaft 2 at its one end. Arm of the adjustment element 3 is connected to adjustment shaft 6 by means of a rotating holder 5, the adjustment shaft 6 rests in the housing of the working head with the ability to rotate around an axis parallel to the axis of rotation of the dyeing shaft 2. The angle of rotation of the adjustment shaft 6 is controlled mechanically by an adjustment handle 8, so that the simultaneous and interdependent rotation of the adjustment shaft 6 together with the rotating holder 5 leads to a rotation of the adjustment element 3 and change of the width of the gap between the adjustment plate and dyeing shaft 2. In the embodiment shown in figures 8, 9 and 10, the adjustment handle 8 rotates a precision screw 28 connected to a precision nut 27, which precision screw 28 with its lower end abuts and presses one end of a spring-loaded plate 30, which presses a tensioned spring 29 in the housing. At its other end, the spring-loaded plate 30 is connected to the adjustment shaft 6 through a screw, so that it rotates it during its up-and-down movement due to the pressure of the precision screw. Thus, the rotary motion of the handle 8 around a vertical axis, through the spring-loaded plate 30, is converted into a rotary motion of the adjustment shaft 6 around a perpendicular axis. The holder 5 of the adjustment element 3 is attached with a screw assembly to the adjustment shaft 6. Rotation of the adjustment shaft 6 in one direction leads to opening of the gap between the adjustment plate and dyeing shaft 2, thus increasing the thickness of the dye layer, and rotation in opposite direction leads to narrowing of the gap. The dye layer thickness adjustment system can adjust the layer thickness, for example, in 70 micron increments, or alternatively 60 micron, 80 micron, or other suitable increment. The adjustment system can have, for example, 8 positions or different number of positions.

[0040] Principle of operation of an exemplary embodiment of the device for dyeing leather products, according to the invention: 1. The dye container 7 is loaded with dye of desired color. Alternatively, a pre-filled bag of dye can be inserted; 2. The electric motor 22 is started by means of the control unit 20. The necessary work speed can be selected by means of the control buttons 23. After the electric motor 22 starts, it transmits the rotary motion by means of the mechanical coupling 17 to the two parts 15 and 16 of the magnetic coupling, which results in rotation of the dyeing shaft 2; 3. Using gravity, the dye moves from the dye container 7 into the dye inlet 12 in the housing, through which it reaches the beginning of the second screw pump 13. The second screw pump 13 pushes the dye supplied in this way to the dye inlet 14 at one end of the dyeing shaft through which inlet 14 the dye enters the dye channel 1 of the dyeing shaft 2. The created pressure moves the dye through the dye channel 1 to the beginning of the working area of the dyeing shaft 2; 4. The dye leaves the channel 1 of the dyeing shaft 2 and enters cavity of the adjustment element 3, which acts as a temporary reservoir, from which the dye is applied to the outer surface of the dyeing shaft 2 in an even layer. The adjustment of the dye layer is carried out by moving away or closer the edge of the adjustment plate 3 with respect to the working section of the dyeing shaft 2. Moving away or closer is done, for example, by rotating the adjustment plate around the central axis of the adjustment shaft 6. The transmission of rotation from the adjustment shaft 6 to the adjustment element 3 is done by means of the rotating holder 5. The rotation of the adjustment shaft 6 is carried out by means of the adjustment handle 8. The thickness of the dye layer is determined by the adjustment system of the machine. 5. When the dye reaches the end of the working area of the dyeing shaft 2, it passes through the hole in the bearing sleeve 4 and enters the circulation cavity of the housing of the working head at one (front) end of the first screw pump 9. It pumps the dye to its other (rear) end where the dye is returned through the dye outlet 10 in the housing back to the dye container 7. In this way the dye has made a complete circle, passing from the dye container 7 through the dye inlet 12 of the housing, the second screw pump 13, entering the channel 1 of the dyeing shaft 2, passing through the outer part of the dyeing shaft 2, its thickness was determined by the adjustment plate, and the excess dye that was not applied to the leather product, has passed through the bearing sleeve 4, through the first screw pump 9, through the dye outlet 10 of the housing, and has returned to the dye container 7. To prevent the dye from passing to the second screw pump 13 when returning to the dye container 7, the insulating ring 11 is provided, which separates the first screw pump 9 from the second screw pump 13 and, accordingly, the first from the second part of the circulation cavity. Thus, the dye returns to the dye container 7 and does not pass to the second screw pump 13.

[0041] It will be clear to those skilled in the art that various modifications of the mobile device for dyeing leather products are possible, which also are within the scope of the invention as defined in the appended claims. All parts of the device can be replaced with technically equivalent elements.

[0042] The reference numbers of the technical features are included in the claims solely for the purpose of increasing the comprehensibility of the claims and, therefore, these reference numbers do not have any limiting effect on the interpretation of the elements indicated by these reference numbers.

Examples

Embodiment Construction

[0021]The replaceable working head of the device for dyeing leather products, according to a non-limiting embodiment of the invention shown in the figures, comprises a housing in which a dyeing shaft 2, resting in bearings in the housing, and a coupling which transmits rotary motion from the drive electrical motor 22 to the dyeing shaft 2 are arranged. A dye container 7 is attached to the housing, the outlet of which is connected to a dye inlet in the housing. The dye container 7 is attached to the housing, for example, with a tight connection through an O-ring or in another suitable way, and the dye is fed from the container to the dyeing shaft 2. The container can have hard walls or it can be a replaceable soft-walled bag pre-filled with dye. The container 7 can have an upper dye filling opening and at least one lower dye outlet opening.

[0022]There is a central dye channel 1 in the dyeing shaft 2 with dye inlet 14 at one end and dye outlet at the other end.

[0023]Preferably, the dy...

Technical field

[0001] The invention relates to devices for dyeing leather products, and more particularly to a dyeing device with a replaceable working head for parts of leather products, for example bags, encasers, suitcases and others. The invention is applicable in the field of leather goods.Prior art

[0002] Dyeing the edges of bags is one of the most difficult processes in the production of leather goods. The dyeing process is the application of a layer of dye to the edge of the finished product by a dye roller coated with a precise amount of dosed dye. The dye roller rotates at a certain speed and during this rotation and counter movement of the dyed object, the dye is transferred from the dye roller to the product being dyed. The main parameters and requirements for dyeing the edge of finished products are: thickness of the applied layer; number of applications that must be performed to reach the required quality; drying of the dye in the container of the dyeing device; obtaining an overedging during dyeing - this is the dye remaining on the face of the dyed product, and not only on the edge of the dyed product; speed of movement of the finished product when applying the dye; ability to quickly change colors.

[0003] When dyeing small pieces, this is done at stationary machines by applying a layer of dye to the edges of the pieces. Dyeing finished products is often difficult to do with stationary machines due to the fact that the finished products are large and difficult to hold which hinders their quality dyeing.

[0004] A hand device for dyeing leather products is known, comprising a housing in which a dyeing shaft, supported in the housing, and a drive electric motor connected by a coupling for transmitting rotary motion to the dyeing shaft are arranged, which electric motor has terminals for connection to a source of current and control unit. The devise also has a dye container with an upper dye opening for dye loading and a lower dye opening for feeding dye to the dyeing shaft. The container is mounted directly above the dyeing shaft, and the distance between the lower opening of the container and the dyeing shaft is constant, thus determining the thickness of the dye layer. Disadvantages of the known device are unevenness of the applied dye layer, impossibility of adjusting the thickness of the dye layer, drying of the dye in the container of the dyeing device, unwanted overedging, impossibility for quick change of the colors when dyeing, impossibility of dyeing with low viscosity dyes due to dye leaking from the container as a result of the gravitational pressure created by the vertical container placed on the dyeing shaft.Summary of the invention

[0005] An object of the invention is to create a replaceable working head for a dyeing device for leather products which provides circulation of the dye while preventing it from thickening or drying up and also having the ability for quick changing of dyes of different color.

[0006] Another object is to provide a hand dyeing device that is portable and convenient to work, and can serve the technological process of dyeing the edges of finished products.

[0007] An additional related object is that the hand dyeing device to provide full access to all parts of the product to be dyed and at the same time, the dyeing is of high quality with uniform application of the dye layer.

[0008] These objects are achieved by creation of a replaceable working head for a device for dyeing leather products, comprising a housing in which are arranged a dyeing shaft, resting in the housing, a coupling for connecting the dyeing shaft to a drive unit of the dyeing device for transmitting rotary motion to the dyeing shaft. The replaceable working head also comprises a dye container attached to the housing with the ability to feed dye to the dyeing shaft and mounting parts for a detachable connection of the working head to the drive unit of the dyeing device. According to the invention there is a central channel for dye in the dyeing shaft with dye inlet at one end and dye outlet at the other end. The dyeing shaft has, successively arranged, a dyeing section, ending with the dye outlet and located outside the housing of the replaceable working head, a pump section and a drive section connected to the coupling means. The pump section of the shaft is rotatably located in a sealed circulation cavity of the housing, which is hermetically isolated from the driving section of the shaft. On the pump section of the shaft, there are, arranged successively and immovably fixed, a first screw pump, an insulating ring dividing the circulation cavity into isolated first and second parts, and a second screw pump, located in the second part of the circulation cavity, the outlet end of which is connected to the dye inlet of the dyeing shaft, and the inlet end of which is connected to the dye inlet of the housing. The first part of the circulation cavity ends on the side of the working section of the shaft with a bearing sleeve hermetically connected to the housing in which the dyeing shaft rests, which bearing sleeve has a through hole for receiving the excess dye from the working section of the shaft, which hole is connected to dye cavity in the sleeve. This dye cavity is part of the first part of the circulation cavity of the housing, in which the first screw pump is located, which extends to the dye outlet of the housing. The dye outlet and dye inlet of the housing are connected, respectively, through dye inlet and outlet pipes, to dye container.

[0009] The device also has an adjustment system for adjusting the thickness of the dye layer, comprising an adjustment plate for the thickness of the dye layer, located parallel to the working section of the shaft, and mounted to the housing of the replaceable working head by an adjusting means with the ability to adjust the width of a gap between the dyeing shaft and edge of the adjustment plate.

[0010] In a preferred embodiment of the invention the coupling means is a part of a two parts coupling designed to transmit contactless rotary motion from an electric motor of the dyeing device to the dyeing shaft, wherein said coupling means is a magnetic element mounted on the drive section of the dyeing shaft with the ability of free rotation in the working head housing.

[0011] In one embodiment of the invention, the first screw pump, the insulating ring and the second screw pump are made as one monolithic piece.

[0012] In a preferred embodiment of the invention, the adjustment system for the thickness of the dye layer comprises an adjustment element with elongated housing with a longitudinal groove, one side of the groove being formed by the adjustment plate, and the elongated housing is located next to and parallel to the axis of the dyeing shaft and encases it at least partially. The working section of the dyeing shaft is rotatably located in the longitudinal groove of the adjustment element, so that a temporary reservoir is formed between the walls of the groove and the dyeing shaft for distributing dye on the working section of the dyeing shaft, which temporary reservoir at its one end is connected to the dye outlet of the dyeing shaft. The adjustment element is connected to the housing of the working head of the housing by means of an arm of a rotating holder, mounted to the housing of the working head by means of an adjustment shaft, resting by bearings in the housing of the working head with the ability of rotation around an axis parallel to the rotation axis of the dyeing shaft. The angle of rotation of the adjustment shaft is mechanically controlled by an adjustment handle. The rotating holder with the adjustment shaft, together with the adjustment element, are configured for simultaneous interdependent rotation, adjusting the width of the gap between the adjusting plate and the dyeing shaft.

[0013] In one embodiment of the invention, the dye layer thickness adjustment system is configured to adjust the layer thickness in 70 micron increments.

[0014] The objective is also completed by creating a device for dyeing of leather products comprising a working head with a dyeing shaft, drive unit with an electric motor which has terminals for connection to a source of current and a control unit and a connector configurated to transfer rotational movement from the mentioned electrical motor to the dyeing shaft of the working head. According to the invention, the working head is a replaceable working head as is described in claims 1 through 5, wherein the replaceable working head is hermetically isolated from the drive unit and has mounting parts for releasable connection of the housing of the replaceable working head to the drive unit in the connection area of the dyeing shaft and the electrical motor. The mentioned connector is releasable and includes two separate parts, where the first part is mounted to the driving section of the dyeing shaft with the possibility of free rotation inside the housing of the working head and the second part of the connector is connected to a shaft of the electrical motor in the drive unit. Preferably, the coupling is a two-part magnetic coupling, and is designed to transmit the rotary motion from the electric motor to the dyeing shaft without contact, wherein the first part of the magnetic coupling is mounted on the drive section of the dyeing shaft with the ability of free rotation in the housing of the replaceable working head, and the second part of the magnetic coupling is connected by a mechanical coupling to the shaft of the electric motor, which mechanical coupling is accommodated in bearings with the ability of free rotation relative to the housing of the drive unit and together with the second part of the magnetic coupling.

[0015] Preferably, the mechanical coupling is a fork coupling.

[0016] Preferably, a mechanical locking means is provided for fixing the housing of the working head to the drive unit of the dyeing device in assembled state.

[0017] In a preferred embodiment the dyeing device is configurated as a mobile dyeing device, wherein the drive unit with the electrical motor is formed as a handle of the dyeing device.

[0018] The advantages of the replaceable working head of the dyeing device for leather products according to the invention are: A constructive separation and releasable connection of the working head and the drive unit provides for easy replacement of one working head with a particular color with a working head with a different color. This allows for fast and comfortable replacement of the color of dye in the working process without the need for change of the container and washing of the entire working head. The circulation of dye, through returning of the excess paint in the dye container as well as the hermetic working head through which the dye circulates both prevent the dye from drying and minimizes losses when dyeing. The regulatory system for regulating the thickness of the dye layer, allows for an even application of a dye layer and choosing the thickness.

[0019] The advantages of the hand dyeing device according to the invention are: The compact hand device is mobile and allows for easy dyeing of leather products. The design of the replaceable working head allows the mobile device to work both in a horizontal position of the dyeing shaft and at different angles, including vertical dyeing shaft, when the front part of the dyeing shaft, where the dye outlet is located, is directed upwards, due to the continuous circulation of the dye and sufficient pressure created by the pump. The dyeing device can also operate at an angle of the dyeing shaft of up to about 45 degrees without dripping dye when the front of the shaft is pointing down, due again to dye circulation. Description of the attached figures

[0020] The invention is explained in more detail through preferred embodiments, given as non-limiting the scope of the invention examples, with reference to the attached figures, where: Figure 1 is an axonometric side view of the device for dyeing leather products, according to a preferred embodiment of the invention. Figure 2 is a top view of the mobile device for dyeing leather products, according to a preferred embodiment of the invention as a mobile device. Figure 3 is a longitudinal section along line A-A, of the mobile device for dyeing leather products, according to a preferred embodiment of the invention shown in Figure 1. Figure 4 is a longitudinal section of the device for dyeing leather products, according to a preferred embodiment of the invention, and a partial view of the working head of the device of said longitudinal section. Figure 5 is a schematic view of the mobile device for dyeing leather products, according to a preferred embodiment of the invention, with highlighted dyeing shaft with first screw pump, insulating ring, second screw pump and second part of the magnetic coupling attached thereto. Figure 6 is a schematic view of the mobile device for dyeing leather products, according to a preferred embodiment of the invention, with highlighted electric motor, mechanical coupling and first part of the magnetic coupling in the drive unit. Figure 7 is a schematic view of the mobile device for dyeing leather products, according to a preferred embodiment of the invention, with highlighted, successively arranged, first screw pump, insulating ring, magnetic coupling, mechanical coupling, and electric motor. Figure 8 shows a longitudinal vertical section of an adjustment system for adjusting the thickness of the dye layer, according to a preferred embodiment of the invention. Figure 9 shows a longitudinal horizontal section of the adjustment system for adjusting the thickness of the dye layer, according to the preferred embodiment of the invention shown in Figure 8. Figure 10 is a vertical cross-section of the adjustment system for adjusting the thickness of the dye layer, according to the preferred embodiment of the invention shown in Figures 8 and 9. Exemplary embodiment of the invention

[0021] The replaceable working head of the device for dyeing leather products, according to a non-limiting embodiment of the invention shown in the figures, comprises a housing in which a dyeing shaft 2, resting in bearings in the housing, and a coupling which transmits rotary motion from the drive electrical motor 22 to the dyeing shaft 2 are arranged. A dye container 7 is attached to the housing, the outlet of which is connected to a dye inlet in the housing. The dye container 7 is attached to the housing, for example, with a tight connection through an O-ring or in another suitable way, and the dye is fed from the container to the dyeing shaft 2. The container can have hard walls or it can be a replaceable soft-walled bag pre-filled with dye. The container 7 can have an upper dye filling opening and at least one lower dye outlet opening.

[0022] There is a central dye channel 1 in the dyeing shaft 2 with dye inlet 14 at one end and dye outlet at the other end.

[0023] Preferably, the dyeing shaft 2 is made of a material with high wear resistance, for example stainless steel, which is preferably nitrogenized or having a special coating for wear resistance.

[0024] The dyeing shaft 2 has, successively arranged, dyeing section, ending with the dye outlet and located outside the housing of the working head, pump section and drive section connected to the coupling. The dyeing shaft 2 rests in bearings in the housing of the working head, preferably in two places, as shown in the figures in the front part of the pump section and in the rear part of the drive section. The pump section of the dyeing shaft 2 is rotatably located in a sealed circulation cavity of the housing having cylindrical form. On the pump section of the shaft 2, there are successively arranged and immovably fixed (Fig. 4) so that they rotate together with the dyeing shaft 2, a first screw pump 9, an insulating ring 11, dividing the circulation cavity into isolated first and second parts, and a second screw pump 13 located in the second part of the circulation cavity, the outlet end of which is connected to the dye inlet 14 of the dyeing shaft, and the inlet end of which is connected to the dye inlet 12 of the housing. Thus, through a system of channels and openings, the movement of the dye from the dye container 7 to the working section of the dyeing shaft 2, and the return of unused dye from the dyeing shaft 2 to the dye container 7, are ensured. The insulating ring 9 is of such diameter that it can rotate freely in the circulation cavity of the housing and, at the same time, provide minimum technological clearance between the peripheral surface of the insulating ring 9 and the inner cylindrical surface of the circulation cavity.

[0025] The first part of the circulation cavity ends on the side of the working section of the dyeing shaft 2 with a bearing sleeve 4, hermetically connected to the housing at the wet part, in which bearing sleeve 4 the dyeing shaft 2 rests. Preferably, the bearing sleeve is made of technical plastic with high wear-resistant properties. Preferably, the bearing sleeve 4 is a sliding bearing element designed as a semi-open bearing. The bearing sleeve also has a through hole, which receives the excess dye from the working section of the shaft 2, which hole is connected to a dye cavity in the sleeve 4, which cavity is a part of the first part of the circulation cavity of the housing, in which the first screw pump 9 is located, and which extends to a dye outlet 10 in the housing. The first screw pump 9 sucks the excess dye that enters the first part of the circulation cavity through the hole in the bearing sleeve 4, and transports it to the dye outlet 10 in the housing, which is connected to the dye container 7. Thus, the excess dye goes back to the container.

[0026] The first screw pump 9, the insulating ring 11 and the second screw pump 13 can be made as one monolithic piece, or alternatively be separate pieces which are connected to each other and are preferably made of technical plastic. It is also possible that the first screw pump 9, the insulating ring 11, the second screw pump 13, and the coupling housing are made as one monolithic piece, as shown in Figures 5, 6 and 7. They are preferably made of high resistance technical plastic.

[0027] The dye outlet 10 and dye inlet 12 of the housing are connected, respectively, through dye inlet and outlet pipes, to the dye container 7.

[0028] The speed of rotation of the dyeing shaft also determines the amount of dye, which is supplied by the second screw pump 13 to the front part of the shaft 2 through the dye channel 1. Higher rotation speed of the electric motor 22 causes faster rotation of the dyeing shaft 2 together with the screw pumps, and, accordingly, more dye is pumped from the container and forced by the second screw pump 13 into the dye channel 1 of the dyeing shaft 2. Thus, through the control buttons 23 of the control unit 20, which controls the revolutions of the electric motor 22, the operator increases or decreases the amount of dye supplied to the working section of the dyeing shaft 2 depending on the need. For example, when dyeing wider edges, a larger amount of dye is needed to achieve the specified thickness of the dye layer. The selected speed is shown on the display 21 of the control unit 20.

[0029] The dyeing device, according to the invention, has two parts that are hermetically isolated from each other - a replaceable working head (wet part), in which the dyeing shaft 2 is located, and a drive unit (dry part), in which the electric motor 22 is located. The two parts of the device are releasably connected to each other in the area of the connector between the dyeing shaft 2 and the electrical motor 22. The working head is hermetically isolated from the drive unit. This way the electrical motor 22 is protected from the dye while the whole inner system of cavities of the working head is isolated from the outside air which prevents the circulating dye from drying.

[0030] The dyeing device for leather products also comprises a mechanical locking component for fixing of the working head to the drive unit in an assembled state, which can be, for example, a bayonet connection, or a spring-loaded pin and corresponding groove, or other appropriate means known from the state of the art.

[0031] The electric motor 22 has terminals for connection to a current source, which can be a battery mounted to or in the drive unit, or it can be in a separate power unit outside the drive unit that is wired, via a cable, to the electric motor. Alternatively, the power supply can be external, via a cable, for example, via a USB cable, with a plug, from a central power supply network. In the variants with external power supply (network or separate battery unit), when the dyeing device is a mobile device, it is lightened, and it is more convenient to work, as it tires less the hands of the operator who holds it.

[0032] The electric motor 22 also has terminals for connection to a control unit 20, which can be mounted to the housing of the drive unit (Figs. 1, 2, 3). Alternatively, the control unit 20 can be externally located and connected to the electric motor 22 by cable connection, thus also lightening the variant as a mobile device, and making it more convenient to operate, as it tires less the hands of the operator who holds it. For example, the control unit can be combined with an external battery unit. The control unit 20 serves to control the revolutions of the electric motor 11, and comprises, for example, a microprocessor controller with board 18, display 21 and control buttons 23 for increasing and decreasing the speed of the electric motor 22 (Fig. 2).

[0033] The electric motor 22 can also have a fan 25 for cooling the electric motor 22 located in the housing of the drive unit (Fig. 3).

[0034] In the stationary embodiment of the dyeing device the housing of the power unit is located on and preferably fixed, for example, to the working table or table top. In a preferred embodiment as a mobile device (shown on the figures) drive unit (dry part) in which the electric motor 22 is located and is shaped as a handle 24 of the device.

[0035] In the embodiment shown in the figures (Fig. 3), the housing of the drive unit has an openable rear cap 26 for access.

[0036] The coupling between the dyeing shaft 2 and the electric motor shaft 22 can be mechanical or magnetic, respectively, releasable or combined. In case of a magnetic coupling, it could be known straight or angled magnetic coupling. In the variant shown in the figures (Fig. 3, 6, 7), the coupling is combined and comprises releasable magnetic coupling connected to a non-releasable mechanical coupling 17 and has a housing, preferably made of technical plastic, to allow its operation. The releasable magnetic coupling is made of two parts 15, 16. The magnetic coupling transmits without contact the rotary motion from the electric motor 22 to the dyeing shaft 2, thus dividing the dyeing device into two parts - dry part in which the electrical modules are placed, and wet part where the dyeing takes place. Thanks to the magnetic coupling, it is extremely easy to separate the wet part (the working head) of the machine and clean it, because there are no electrical components in it. Also, in this way, the color used by the mobile device can be easily changed without the need to wash its wet part. This is possible because after the wet part is removed from the mobile device, another working head / wet part loaded with different dye color can be placed in its place and the work can be continued without having to wash the removed wet part. The removed working head with the old color can be placed on a support station that will keep it in working order so that the dye does not dry, while the work with the newly installed working head with the new color can continue. The number of colors, which can be worked with, is not limited as long as there are enough working heads for the device and enough support stations.

[0037] In the preferred embodiment shown in the figures, the two parts 15 and 16 of the releasable magnetic coupling are cylindrical, the first part 16 entering the second part 15 (Figs. 3, 7) which has a central cylindrical cavity. The first part 16 of the magnetic coupling is mounted on the drive section of the dyeing shaft 2 and is located in the circulation cavity in the working head so as to rotate freely in the working head. The second part 15 of the magnetic coupling is connected by a mechanical coupling 17 to a shaft of the electric motor 22, which mechanical coupling 17 is supported by a bearing 19 in the drive unit so that it rotates freely and together with the second part 15 of the magnetic coupling. The end of the housing of the working head, in which the first part 16 of the magnetic coupling is located, is preferably cylindrical and is made of such a diameter that it enters an open cylindrical cavity of the housing of the drive unit, around which the first part 16 of the magnetic coupling is resting. The magnetic field created by the first part 16 of the magnetic coupling passes through the walls of the two housings connected to each other and interacts with the magnetic field of the second part 15 of the magnetic coupling. During the rotation of the first part 16 of the magnetic coupling in the drive unit, the second part 15 of the magnetic coupling in the working head also rotates together with the dyeing shaft 2 and the screw pumps 9 and 11 arranged on it. This design allows non-contact transmission of the rotary motion from the electric motor to the dyeing shaft, wherein the two parts of the dyeing shaft are isolated from each other and at the same time, they are releasably connected to each other.

[0038] The mechanical coupling 17 transmits the rotation from the electric motor 22 to the first part 16 of the magnetic coupling, so as to protect the bearings 19 of the electric motor 22 from possible misalignments and vibrations, since there is a large clearance. The mechanical coupling 17 is, for example, a fork coupling, and consists of a male and a female part, which are mounted, respectively, on the shaft of the electric motor 22 and on the first part 16 of the magnetic coupling. Alternatively, another type of suitable coupling known in the art can be used.

[0039] The dyeing device also has an adjustment system for adjusting the thickness of the dye layer, comprising an adjustment plate for the thickness of the dye layer, located parallel to the working section of the dyeing shaft 2 and mounted to the housing of the replaceable working head by means of an adjustment means, so as to allow adjustment of the width of the gap between the dyeing shaft 2 and the edge of the adjustment plate. The adjustment of the thickness of the dye layer on the dyeing shaft 2 is done, respectively, by manipulation of the adjustment means, which moves away or closer to the dyeing shaft 2 the adjustment plate located parallel to it by rotation of the adjustment plate around the center of the dyeing shaft 2, or by progressive movement, tangentially moving the adjustment plate away from or closer to the dyeing shaft 2. In the embodiment shown in Figures 8 and 9, the adjustment system for the thickness of the dye layer comprises an adjustment element 3 with an elongated housing with a longitudinal groove, one edge of the groove being formed by the adjustment plate. The elongated housing is located next to and parallel to the axis of the dyeing shaft 2 and at least partially encases it. The working section of the dyeing shaft 2 is arranged to be able to rotate freely in the longitudinal groove of the adjustment element 3, so that a temporary reservoir is formed between the walls of the groove and the dyeing shaft 2 for distributing dye on the working section of the dyeing shaft 2. This temporary reservoir is connected to the dye outlet of channel 1 of the dyeing shaft 2 at its one end. Arm of the adjustment element 3 is connected to adjustment shaft 6 by means of a rotating holder 5, the adjustment shaft 6 rests in the housing of the working head with the ability to rotate around an axis parallel to the axis of rotation of the dyeing shaft 2. The angle of rotation of the adjustment shaft 6 is controlled mechanically by an adjustment handle 8, so that the simultaneous and interdependent rotation of the adjustment shaft 6 together with the rotating holder 5 leads to a rotation of the adjustment element 3 and change of the width of the gap between the adjustment plate and dyeing shaft 2. In the embodiment shown in figures 8, 9 and 10, the adjustment handle 8 rotates a precision screw 28 connected to a precision nut 27, which precision screw 28 with its lower end abuts and presses one end of a spring-loaded plate 30, which presses a tensioned spring 29 in the housing. At its other end, the spring-loaded plate 30 is connected to the adjustment shaft 6 through a screw, so that it rotates it during its up-and-down movement due to the pressure of the precision screw. Thus, the rotary motion of the handle 8 around a vertical axis, through the spring-loaded plate 30, is converted into a rotary motion of the adjustment shaft 6 around a perpendicular axis. The holder 5 of the adjustment element 3 is attached with a screw assembly to the adjustment shaft 6. Rotation of the adjustment shaft 6 in one direction leads to opening of the gap between the adjustment plate and dyeing shaft 2, thus increasing the thickness of the dye layer, and rotation in opposite direction leads to narrowing of the gap. The dye layer thickness adjustment system can adjust the layer thickness, for example, in 70 micron increments, or alternatively 60 micron, 80 micron, or other suitable increment. The adjustment system can have, for example, 8 positions or different number of positions.

[0040] Principle of operation of an exemplary embodiment of the device for dyeing leather products, according to the invention: 1. The dye container 7 is loaded with dye of desired color. Alternatively, a pre-filled bag of dye can be inserted; 2. The electric motor 22 is started by means of the control unit 20. The necessary work speed can be selected by means of the control buttons 23. After the electric motor 22 starts, it transmits the rotary motion by means of the mechanical coupling 17 to the two parts 15 and 16 of the magnetic coupling, which results in rotation of the dyeing shaft 2; 3. Using gravity, the dye moves from the dye container 7 into the dye inlet 12 in the housing, through which it reaches the beginning of the second screw pump 13. The second screw pump 13 pushes the dye supplied in this way to the dye inlet 14 at one end of the dyeing shaft through which inlet 14 the dye enters the dye channel 1 of the dyeing shaft 2. The created pressure moves the dye through the dye channel 1 to the beginning of the working area of the dyeing shaft 2; 4. The dye leaves the channel 1 of the dyeing shaft 2 and enters cavity of the adjustment element 3, which acts as a temporary reservoir, from which the dye is applied to the outer surface of the dyeing shaft 2 in an even layer. The adjustment of the dye layer is carried out by moving away or closer the edge of the adjustment plate 3 with respect to the working section of the dyeing shaft 2. Moving away or closer is done, for example, by rotating the adjustment plate around the central axis of the adjustment shaft 6. The transmission of rotation from the adjustment shaft 6 to the adjustment element 3 is done by means of the rotating holder 5. The rotation of the adjustment shaft 6 is carried out by means of the adjustment handle 8. The thickness of the dye layer is determined by the adjustment system of the machine. 5. When the dye reaches the end of the working area of the dyeing shaft 2, it passes through the hole in the bearing sleeve 4 and enters the circulation cavity of the housing of the working head at one (front) end of the first screw pump 9. It pumps the dye to its other (rear) end where the dye is returned through the dye outlet 10 in the housing back to the dye container 7. In this way the dye has made a complete circle, passing from the dye container 7 through the dye inlet 12 of the housing, the second screw pump 13, entering the channel 1 of the dyeing shaft 2, passing through the outer part of the dyeing shaft 2, its thickness was determined by the adjustment plate, and the excess dye that was not applied to the leather product, has passed through the bearing sleeve 4, through the first screw pump 9, through the dye outlet 10 of the housing, and has returned to the dye container 7. To prevent the dye from passing to the second screw pump 13 when returning to the dye container 7, the insulating ring 11 is provided, which separates the first screw pump 9 from the second screw pump 13 and, accordingly, the first from the second part of the circulation cavity. Thus, the dye returns to the dye container 7 and does not pass to the second screw pump 13.

[0041] It will be clear to those skilled in the art that various modifications of the mobile device for dyeing leather products are possible, which also are within the scope of the invention as defined in the appended claims. All parts of the device can be replaced with technically equivalent elements.

[0042] The reference numbers of the technical features are included in the claims solely for the purpose of increasing the comprehensibility of the claims and, therefore, these reference numbers do not have any limiting effect on the interpretation of the elements indicated by these reference numbers.

Examples

Embodiment Construction

[0021]The replaceable working head of the device for dyeing leather products, according to a non-limiting embodiment of the invention shown in the figures, comprises a housing in which a dyeing shaft 2, resting in bearings in the housing, and a coupling which transmits rotary motion from the drive electrical motor 22 to the dyeing shaft 2 are arranged. A dye container 7 is attached to the housing, the outlet of which is connected to a dye inlet in the housing. The dye container 7 is attached to the housing, for example, with a tight connection through an O-ring or in another suitable way, and the dye is fed from the container to the dyeing shaft 2. The container can have hard walls or it can be a replaceable soft-walled bag pre-filled with dye. The container 7 can have an upper dye filling opening and at least one lower dye outlet opening.

[0022]There is a central dye channel 1 in the dyeing shaft 2 with dye inlet 14 at one end and dye outlet at the other end.

[0023]Preferably, the dy...

Claims

1. Dyeing device replaceable working head for dyeing leather products comprising a housing in which are arranged a dyeing shaft (2), resting by bearings in the housing, a coupling means for connecting the dyeing shaft (2) to a drive unit of the dyeing device for transmitting rotary motion to the dyeing shaft (2), and a dye container (7) attached to the housing with the ability to feed dye to the dyeing shaft (2), characterized in that there are also mounting parts for a detachable connection of the replaceable working head to the dyeing device, wherein there is a central channel for dye in the dyeing shaft (2) with a dye inlet (14) at one end and a dye outlet (1) at the other end, wherein the dyeing shaft (2) has, successively arranged, dyeing section ending with the dye outlet (1) and located outside the housing of the replaceable working head, a pump section, and a drive section connected to the coupling means, wherein the pump section of the dyeing shaft (2) is rotatably located in a sealed circulation cavity of the housing, said circulation cavity being hermetically isolated from the drive section of the dyeing shaft (2), wherein on the pump section of the dyeing shaft (2) there are, successively arranged and immovably fixed, a first screw pump (9), an insulating ring (11) dividing the circulation cavity into isolated first and second parts, and a second screw pump (13) located in the second part of the circulation cavity, the outlet end of which is connected to the dye inlet (14) of the dyeing shaft, and the inlet end of the second part of the circulation cavity is connected to the dye inlet (12) of the housing, wherein the first part of the circulation cavity ends on the side of the working section of the dyeing shaft (2) with a bearing sleeve (4) hermetically connected to the housing in which the dyeing shaft (2) rests, which bearing sleeve (4) has a through hole for receiving the excess dye from the working section of the shaft (2), which hole is connected to dye cavity in the sleeve (4), which cavity is part of the first part of the circulation cavity of the housing, in which the first screw pump (9) is located, which extends to a dye outlet (10) of the housing, wherein the dye outlet (10) and dye inlet (12) of the housing are connected, respectively, through dye inlet and outlet pipes, to dye container (7).

2. Dyeing device replaceable working head for dyeing leather products according to claim 1, characterized in that the coupling means is a part of a two parts coupling designed to transmit contactless rotary motion from an electric motor (22) of the dyeing device to the dyeing shaft (2), wherein said coupling means is a magnetic element mounted on the drive section of the dyeing shaft (2) with the ability of free rotation in the working head housing.

3. Dyeing device replaceable working head for dyeing leather products characterized in that the first screw pump (9), the insulating ring (11) and the second screw pump (13) are made as one monolithic piece.

4. Dyeing device replaceable working head for dyeing leather products according to each of the previous claims, characterized in that there is an adjustment system for regulating the thickness of the dye layer, comprising an adjustment plate for thickness of the dye layer, placed parallelly to the working section of the dyeing shaft (2) and mounted to the housing of the working head an adjusting means with the ability to adjust the width of a gap between the dyeing shaft (2) and the edge of the adjustment plate.

5. Dyeing device replaceable working head for dyeing leather products according to claim 4, characterized in that the adjustment system for the thickness of the dye layer comprises an adjustment element (3) with elongated housing with a longitudinal groove, one side of the groove being formed by the adjustment plate, the elongated housing of the adjustment element (3) is located next to and parallel to the axis of the dyeing shaft (2) and encases it at least partially, and the working section of the dyeing shaft (2) is rotatably located in the longitudinal groove of the adjustment element (3) so that a temporary reservoir is formed between the walls of the groove and the dyeing shaft (2) for distributing dye on the working section of the dyeing shaft (2), which temporary reservoir at its one end is connected to the dye outlet (1) of the dyeing shaft (2), wherein an arm of the adjustment element (3) is connected to an adjustment shaft (6) by means of a holder (5), and the adjustment shaft (6) rests by bearings in the housing of the working head with the ability of rotation around an axis parallel to the axis of rotation of the dyeing shaft (2), wherein the angle of rotation of the adjustment shaft (2) is mechanically controlled by an adjustment handle (8), wherein the rotating holder (5) with the adjustment shaft (6), together with the adjustment element (3) are configured with the ability of simultaneous interdependent rotation, adjusting the width of the gap between the adjustment plate and dyeing shaft (2).

6. Dyeing device replaceable working head for dyeing leather products according to claims 4 or 5, characterized in that the dye layer thickness adjustment system is configured to adjust the layer thickness in 70 microns increments.

7. Dyeing device for dyeing leather products comprising a working head with a dyeing shaft (2), a drive unit with electric motor (22) that has terminals for connection to a current source and a control unit (20), and a coupling unit configured to transmit rotary motion of said electric motor (22) to the dyeing shaft (2), characterized in that the working head is a replaceable working head as described in claims 1 to 6, wherein the replaceable working head is hermetically isolated from the driving unit, and there is mounting means for releasable connection of replaceable working head and driving unit to each other in the region of the coupling unit between the dyeing shaft (2) and the electric motor (22), wherein said coupling unit is detachable and comprised two separate parts, wherein the first part (16) of the coupling unit is mounted on the drive section of the shaft (2) with the ability of free rotation in the housing of the working head, and the second part (15) of the coupling unit is connected to the shaft of the electric motor (22).

8. Dyeing device for dyeing leather products according to claim 7, characterized in that the coupling unit is a magnetic coupling composed of two parts (15, 16), which is designed to transmit contactless rotary motion from the electric motor (22) to the dyeing shaft (2), wherein the first part (16) of the magnetic coupling is mounted on the drive section of the dyeing shaft (2) with the ability of free rotation in the housing of the working head, and the second part (15) of the magnetic coupling is connected by a mechanical coupling (17) to the shaft of the electric motor (22), which mechanical coupling (17) rests by bearings with the ability of free rotation relative to the drive unit housing and together with the second part (15) of the magnetic coupling.

9. Dyeing device for dyeing leather products according to claim 8, characterized in that the mechanical coupling (17) is a fork coupling.

10. Dyeing device for dyeing leather products according to any of the claims from 7 to 9, characterized in that a mechanical locking means is provided for fixing the housing of the replaceable working head to the drive unit of the dyeing device in assembled state.

11. Dyeing device for dyeing leather products according to any of the claims from 7 to 10, characterized in that the dyeing device is configured as a mobile dyeing device, wherein the drive unit with the electric motor (22) is shaped as a handle (24) of the device.

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