Technical Field

The invention relates to a process for producing the metal furniture connection element cam by shaping the roll metal sheet with a press in the first stage and subsequently a continuous bending, folding, and cutting the roll sheet with a roll form machine.

State of the Art

Connection elements are elements or mechanisms capable of attaching at least two furniture units or pieces of furniture or any other article as a result of a mechanical process. Connection elements can be defined as fittings that can be prepared in different systems, various diameters, and sizes.

Today, with the widespread use of home-mounted disassembled furniture systems, the use of practical and easy-to-install connection elements is also increasing. Such connection mechanisms can allow the user to easily assemble and provide a more consistent use if the furniture is re-assembled-disassembled.

As the use of demounted furniture systems increases, the interest in eccentric connection elements used to connect them is increasing today.

One of the most important examples of eccentric connection elements is minifix connection elements.

Minifix is one of the most durable and practical ways to connect furniture.

Minifix connections generally aim to connect and join the chipboard or MDF furniture component. For this purpose, the minifix consists of a shaft and body, which can be mostly metal. The minifix connection operates on the principle that the end of the shaft is placed in the groove formed in the body and then the shaft is fixed to the body in a certain position with the movement of the body.

For this purpose, the minifix body is placed in a hole formed on the furniture component and forms a hole for the shaft to enter the other furniture component that corresponds to it.

For this purpose, the body of the minifix connection elements is mostly formed in the form of cylinders and can be connected to the furniture component. This body structure, which is formed in a cylindrical form, must have different openings and channels on it in order to take the shaft and lock it.

Patent applications EP0898089 and WO2018197219 refer to connection elements that can be given as examples of classic minifix bodies.

The conventional minifix bodies have channels and gaps in their structure for connecting and locking the shaft to the body. This structure necessitates the folded and 3-dimensional structure of the minifix body as shown in the applications EP0898089 and WO2018197219.

In order to create this folded body structure, the application numbered WO2018197219 describes that the minifix body can be produced by casting using zinc or aluminum-based materials.

According to the description of the relevant application, it is understood that all the parts that make up the connection assembly are made of zinc cast metal parts.

Patent document US2004161294 describes the body of a similar minifix connection apparatus. According to the description of the patent application, the connection element is used to releasably engage the two plates, in particular the furniture plates. For this purpose, it is understood that the connection element comprises a clamping element (body) rotatably mounted in a slot between a released position and a locked position. It is understood here that the clamping element enables locking by including the end portion of a corresponding clamping bolt. Due to the difficulties associated with the manufacture of the minifix connection apparatus, it is understood that the embodiment of the patent document US2004161294 consists of an upper part and a lower part that can be interlocked. It is also described that the connection element according to description can be produced by an injection molding process using a single injection machine.

However, in order to operate the solution described in the patent document US2004161294, the components of the body consisting of more than one part will have to be produced separately and then combined and operated. This may cause the production process to become more difficult and increase production costs.

The solution of manufacturing the body consisting of more than one lower part separately and joining it later also emerges due to the folded and complex structure of the minifix body.

Examples of ordinary state of the art are also patent application TR 2020/08952.

In application 2020/08952, a minifix eccentric furniture connection element cam forged from a steel sheet is described. It is understood that within the application, it is also described in the process for the production of the said cam. It is thought that it is aimed to eliminate the technical problems experienced in the minifix connection elements made of zamak.

The said production method aims to form a single part by forging, crushing, and cutting the connection element from a steel sheet. This production method aims, more particularly, to apply this process with a single machine. The final structure can be formed by forging, crushing, cutting, and bending the steel sheet with the desired grift shape with the H press machine and progressive mold.

Performing the 3-dimensional and folded structure of the connection element cam in the same press with a single process will make it difficult to operate the production continuously.

The use of the press in the production process and all the forging, crushing, cutting, and bending processes in the mold with the same mold make the production process difficult. The most important technical obstacle within this application is the use of a single mold and a single press. Performing all forging, crushing, cutting, and bending processes in the same mold will require the mold to have all mold sections in its structure that can perform subprocesses of these processes.

The easiest solution to increase the production amount is to increase the mold size.

Considering the order and variety of the processes applied by the mold, the fact that the mold contains a large number of sub-sections already causes the mold to be very wide. Therefore, even if the mold is enlarged, the amount of product to be produced remains limited due to the press sizes.

Again, enlarging the dimensions of the mold will require increasing the size and power of the press to be used, which may lead to an increase in production costs.

Attempting to perform a large number of operations with a single pressing requires distances between the mold sections and may cause a high amount of waste during the process on the steel sheet.

All of these operations must be done with vertical presses. According to the description of the application numbered 2020/08952, these presses can be in the form of H presses. As mentioned above, the application of all processes in the same mold and a single press leads to significant reductions in production speed and makes the process very complex.

As is known, such molds require the use of a plurality of pins to perform the said operations. Since these pins carry out operations by impact, if the pins are worn and broken, the production process must be completely stopped if even a single pin is damaged. Since this will require a break in production, it will be able to create a significant handicap during production.

Again, the necessity of continuous operation of the press will cause heating in both the mold and the machine in long-term operation. As a result, it may not be possible to increase the processing speed above certain limits within this application. For the production method described in application 2020/08952, for example, it may be possible to have about 130 pins of the mold in the H vertical press. There is a pin bearing that will be suitable for the operation in which each pin is applied.

Since the number of pins and pin bearings will need to be increased with these ratios to increase the amount of product to be produced in the unit time, the dimensions of both the press and the mold may increase significantly.

Again, this system will need to be operated by keeping a distance both on the mold and on the steel sheet of each pin bearing. Otherwise, unwanted fractures may occur during the processes applied. Considering that the total amount of pins operated is around 130, it can be understood how high the amount of waste that may occur is.

Problems to be solved by the Invention

The object of the invention is to provide a more efficient and fast production method for the formation of a minifix eccentric furniture connection element cam made of steel sheet.

For this purpose, the sheet is shaped with relatively smaller presses in the form of strips opened from the steel sheet roll, and then the sequential parts shaped in strips are formed on the tape without separating from the tape. This intermediate product is fed into a roll form machine containing successive folding and bending elements in the form of a drum (cylinder) in the form of a strip without separating from each other, it continuously flows in the drums of this machine and a 3-dimensional minifix cam body can be formed by folding and bending while sliding under the effect of the drums in this horizontal movement. Consecutive minifix cam bodies formed in the folded and 3-dimensional form on a strip can be cut in the final stage and the final product can be formed.

Since this method will allow the continuous production of minifix cams, the production speed can be increased.

For example, while molding with a single vertical press (this process cannot exceed certain limits since it restricts the press and mold sizes) can allow 120 products to be taken per minute, 500-600 products can be taken over a single line with the continuous system of the invention.

Since the method of the invention allows more than one line to be operated, the above- mentioned product quantities can be increased in proportion to the number of lines used.

Since roll form machines will allow more than one line to be operated independently at the same time, the production line can also be operated using 3 or 4 roll form lines. This situation will both reduce production costs and cause a significant increase in production speed.

Description of the Figures

Figure 1. A top view of a section of intermediate product strip formed without separation as a result of pressing of steel sheet

Figure 2. A view of the minifix eccentric furniture connection element cam formed from steel sheet in folded and 3-dimensional form after production

Figure 3. A schematic view of the production line of the minifix eccentric furniture connection element cam formed from steel sheet

Description of References in Figures

1. Sheet roll

2. Strip

3. Press unit

4. Intermediate product strip

5. Roll form line

5.1. Roll form cylinder

6. Cutting unit

7. Flat body profile part with unfolded structure

8. 3-dimensional minifix body with folded structure

Description of Invention The process for the production of the 3-dimensional and folded metal furniture connection element minifix cam body comprises the following process steps.

• Opening the steel sheet from the sheet roll (1) as a strip (2) and feeding it to the press unit (3),

• By pressing strip (2) in the press unit (3) by means of a mold, forming the intermediate product strip (4) in which the flat profile parts with unfolded structure (7) are sequentially arranged,

• Feeding the intermediate product strip (4) from the press unit (3) to at least one roll form line (5) without separating from the production band,

• Creating the intermediate product strip (4) including folded and 3-dimensional consecutive parts folding and bending while sliding under the effect of the cylinders (5.1) in the roll form line (5) by moving the intermediate product strip (4) horizontally between the roll form cylinders (5.1) formed in a structure and number in accordance with the 3-dimensional minifix body with folded structure (8),

• Feeding the 3-dimensional minifix bodies with folded structure (8), which are consecutively formed on the intermediate product strip (4), to the cutting unit (6) and forming the final product by cutting.

According to the preferred embodiment of the invention, the cutting unit (6) used for cutting the 3-dimensional minifix body with folded structure (8) after the roll form line (5) can be in the form of a guillotine. In this embodiment, the cutting unit is equipped with a sensor. The sensor detects the speed of the strip of a 3-dimensional minifix body with a folded structure (8) flowing to the cutting unit and can control the servomotor controlling the cutting speed of the guillotine in this direction.

The servomotor shall be able to control the cutting speed of the guillotine in accordance with the data received from the sensor.

Guillotine and sensors operated connected to the servomotor shall allow cutting the strip formed at the end of the line at high speed and from a single point. The roll form line (5) of the invention can contain a different number of roll form cylinders (5.1) in accordance with the folded and 3-dimensional structure of the final product to be produced.

The intermediate product strip (4) bends and bends with the sheet bending cylinders poured into the roll form line. It can then be folded with folding rollers.

The intermediate product strip (4) progresses with the continuous change between the cylinders (5.1), firstly it ensures that the flat body profile part with unfolded structure (7) is bent, and then the cylinders (5.1) formed in front of the line aim to fold the parts (7) and at the end, it is pressed with the side friction thrust and compressed.

For this purpose, the cylinders (5.1) formed in the first and middle part of the roll form line (5) on the side of the press unit (3) have the purpose of bending, while the cylinders (5.1) formed towards the end of the roll form line (5) have the purpose of folding.

Different applications of the invention can be operated by using more than one press unit (3) and/or more than one roll form line (5).

This embodiment may both lead to an increase in production speed and a decrease in production costs.

For this purpose, each press unit (3) can be connected to the roll form lines (5) separately to feed the intermediate product strip (4).

In different embodiments of the invention, it is also possible to connect a single press unit (3) to more than one roll form line (5) by feeding.