ES1065405U - Tiltable milling head with a built in automatic speed changer - Google Patents

Abstract

This invention relates to the milling head with a built In automatic speed changer wherein the speed change system (1) is mounted inside the milling head (2), near the spindle (3). The head consists of two joints with tilted sides (2, 4), so when they are set in motion they place the spindle in a horizontal, vertical or any other position within the 360 degrees. They can be operated manually or automatically. The transmission for rotating the spindle (and for automatic head adjustment operations) is powered/driven by the main electric motor (5) (variety of power and adjustable speeds), which through transmission (6) consisting of ball bearings, a shaft and gears leads to (passing through machine components and. its head) the speed adjustment system located at the end portion of the head (2) where the spindle shaft (3) is located. In this section, the last transmission bevel gear (7) is not in contact with the spindle (3) as is the case in standard milling heads, but rather through a movable coupling/lever (8) consisting of a high-speed gear (9) and a low-speed gear (10) which is directly connected to the spindle actuates the first gear (11) of the speed change system and here is where the first increase of speed is achieved. The speed change system gear (11) is in direct contact with gear (12) which is connected to the fixed spindle gear (13) and here is where the high speed takes place. This connection provides for the high rotation speed of the milling heads spindle (3), which is controlled by the main motor (5). In order to achieve low speeds, a hydraulic, pneumatic or electric cylinder is used to move the mobile coupling (8) to a position which will switch off the high-speed gear (11), namely for turning off rotation multiplication at the same time the low-speed gear (10) is connected to the gear (14) which is fixed to the spindle (3) and thus direct connection of the bevel gear (7) with the spindle (3) is achieved. Consequently, low-speed that is controlled by the main motor (5) is reached.

Description

Milling head with automatic change of integrated speed

Sector of the technique to which the invention relates

The invention belongs to the parts sector constitutive or accessories suitable for machine tools, regardless of whether or not they can replace any part of the Work area of the machine tool.

The object of the invention is designated and classified according to the International Patent Classification (CIP) with the designation B 23 C 9/00.

Technical problem raised

The technical problem that is solved with this statement is as follows: how to build a milling machine that run at low revolutions, with torque corresponding, and at the same time can work at high speed Spindle rotation for final treatments. The problem Technician cited is solved with the use of the milling head with integrated automatic gearshift.

State of the art

The author does not know the solutions of the problem that are identical to the invention described in this patent declaration.

The projected head according to this statement solve the problems that are currently the machine tool manufacturers, that is, offers the possibility of building a machine that mills at low revolutions, with the corresponding moment, which at the same time It can work at high spindle rotation speed for final treatments (for example, molds). Currently this problem is being partially resolved by mounting a large engine (390 kg) of great power and torque to achieve a small reduction in transmission ratio of the rotation of the pulleys, there is the possibility of reaching  high revolutions (approx. 6000 rpm), but, for the moment, that It produces some problems. In this way all automatisms they work at high revolutions (6000) which causes problems of bearing overheating (the refrigerator must be provided to cool the ball bearings), the problem of precision maintenance of the machine, fast expense of the mechanical - especially of pairs of conical sprocket wheels and there is also the problem of a lot of noise and the balance of vertical axis.

Description of the technical problem solution

The construction of the head according to the Patent declaration allows the use of a spindle motor smaller in power and size (180 kg), and therefore ensures financial savings, automatisms will work with a 3000 rpm maximum without refrigeration, and the only piece that will turn fast, it will be the head spindle jelly connected with the gearshift, which will provide a higher speed than the current 6000 revolutions.

Description of the drawings

The invention is illustrated in more detail in The following drawings:

Drawing 1 - automation scheme, version one

Drawing 2 - automation scheme, version 2

Drawing 3 - section of the change zone speeds

Drawing 4 - detail of the head.

The speed change system (1) is housed inside the milling head (2) near the spindle (3). The head is made of two oblique joints (2, 4) and they, when moving, place the spindle with each other in the horizontal, vertical or other position within 360º, with the manual or automatic start-up.

The transmission used to turn the spindle (and to place the head in the case of automatic) comes from main electric motor (5) of different powers and different adjustable speeds that through the transmission mechanism composed of the ball bearing, enjulio and cogwheel (passing by the machine parts and its head) reaches the system of speed change lodged in the extreme part of the head (2) where the spindle axis is located (3).

In this place the last conical cogwheel of the transmission (7) is not connected to the spindle (3) as in the case of normal milling heads, but by means of a clutch mobile (8) consisting of a high speed gear wheel (9) and another gear wheel for low speed (10) directly connected with the spindle (now disconnected), start moving the first gear (11) of the speed change system and here It is where the first speed increase is reached. The same wheel gear (11) of the speed change system is in contact directly with another gearwheel (12) connected to the gearwheel fixed spindle (13) thus performing the second increase of speed With this connection high speed of the milling head spindle (3) regulated by the main motor (5). To obtain low speeds by cylinder hydraulic, pneumatic or electric we move the mobile clutch (8) until disconnecting the high speed sprocket (11) and by consequently, we disconnect the multiplication of revolutions; to the at the same time we are gearing the low speed sprocket (10) on the gearwheel (14) fixed on the spindle (3) and we get direct connection of the conical gearwheel (7) with the spindle (3) and the consequence will be the low speed regulated by the engine main (5).

In the phase of change of speed through the cylinder, there is the neutral zone where no gear wheel is connected with the other, and thus the position in which the Transmission is disconnected.

The hydraulic, pneumatic or electric cylinder used to move the speed clutch is controlled by two sensors that send information about speeds in which is the head to the machine control.

Thanks to the position where the gearshift system, the machine elements are "spend" less because the spindle (3) is the only element that works at high speeds, while the other elements they work at low speeds because they are in succession before the speed change system itself.

Automation version number 1

The machine of 22 kw, of maximum revolutions of the 6000 rpm spindle and torque of 600 Nm. The engine with the direct transmission Currently we must use the 29.5 kW motor with the torque of 410 Nm, basic revolutions 500 rpm (the Siemens catalog), the ratio of pulleys 1.65,  maximum engine revolutions of 7000 rpm (it is a special case, the standard engine works at 5000 revolutions and that's why the price it will also rise almost double).

Therefore: 7000: 1.16 = 6034 revolutions of all automatisms up to the spindle, the torque of the spindle is 475 Nm with a minimum of revolutions for milling Power 431. Spindle revolutions from 0 to 6000 rpm. The alternative is the assembly of the speed changes after engine, but they also involve a certain cost and need to continuous lubrication at a constant temperature and the only thing that way It is solved is the size of the engine. You have to keep in mind that the bearings on which the ball bearings are mounted (which must also be special because of the high speed) must be made in such a way that they allow the cooling liquid to pass through, which makes its price also exceed the price of bearings of standard balls.

Automation version number 2

The 8000 engine: 3 rpm (pulley ratio) = 2666 rpm maximum of all automations except spindle of the tool carrier, the only one that has the bearings of high speed balls - 210 (engine torque) x 3 = 630 Nm in the spindle with a minimum of revolutions the milling of power 333.

Spindle revolutions from 0 to 9400 rpm (in the case of the engine with the option of 10,000 rpm, the number of revolutions can reach up to 11500 rpm without assuming any problem for the spindle because it is lubricated, just like the head whole, with air + oil spreading).

In this example of embodiment it was obtained best result with the automatic change head project of integrated speeds, achieving optimal results with the ISO 50 spindle of 22 kw (the same system is valid for others head sizes), thus reducing the expenses of components. The head is projected so that it can be mounted about existing machine tools, especially about the oldest that surely work at low revolutions of the spindle, making a small change in the connection between two pieces. The speed change is made up of a pair of wheels toothed that through the hydraulic cylinder connects with the Low or high speed sprocket directly to the spindle. This position is controlled by two sensors connected to the machine control

Claims (6)

1. Milling head with integrated automatic gearshift, characterized in that the speed change system (1) is housed inside the milling head (2), near the spindle (3), and the head is made of two oblique joints (2, 4) and they, when moving, place the spindle with each other in the horizontal, vertical or other position within 360º, with manual or automatic start-up, while the transmission used to rotate the spindle (and to place the head in the case of automatic) comes from the main electric motor (5) of different powers and different adjustable speeds that through the transmission mechanism composed of the ball bearing, enjulio and cogwheel (passing through the parts of the machine and its head) reaches the speed change system housed in the extreme part of the head (2) where the spindle axis (3) is located, and where the last conical gear wheel of the transm ision (7) is not connected to the spindle (3) as in the case of normal milling heads, but by a mobile clutch (8) consisting of a high speed gear wheel (9) and another low speed gear wheel ( 10) connected directly to the spindle (at this time disconnected), the first gear wheel (11) of the speed change system begins to move and this is where the first speed increase is reached, but the same gear wheel (11) of the speed change system is in direct contact with another gearwheel (12) connected to the spindle's fixed gearwheel (13) thus carrying out the second speed increase resulting in high spindle speed (3) of the head of milling regulated by the main engine (5). 2. The milling head according to claim 1, characterized in that by means of a hydraulic, pneumatic or electric cylinder, it moves the mobile clutch (8) until the high-speed cogwheel (11) is disconnected and consequently, the speed multiplication is switched off; at the same time the low speed gearwheel (10) is being engaged in the gearwheel (14) fixed in the spindle (3) and the direct connection of the conical gearwheel (7) is achieved with the spindle (3) and the consequence will be the low speed regulated by the main engine (5). 3. The milling head according to claims 1 and 2, characterized in that in the first version the machine of 22 kw, of maximum spindle revolutions 6000 rpm and torque of 600 Nm is used with the motor with direct transmission, while that in the exemplary embodiment, the 29.5 kW motor must be used with the torque of 410 Nm, basic revolutions of 500 rpm (the Siemens catalog), the ratio of the pulleys 1.65, maximum engine revolutions of 7000 rpm, which means: 7000: 1.16 = 6034 revolutions of all automatisms up to the spindle, the torque of the spindle is 475 Nm with a minimum of revolutions for milling power 431, while the spindle revolutions are of 0 to 6000 rpm - the alternative is the assembly of the speed changes after the engine, but they have the need for continuous lubrication at a constant temperature and the only thing that is solved is the size of the engine and taking into account that the bearings on which the ball bearings are mounted (which must also be special due to the high speed) must be made in such a way that they allow the cooling liquid to pass, which means that their price exceeds the price of Standard ball bearings. 4. The milling head according to claims 1 - 3, characterized in that the second version of the motor is 8000: 3 rpm (ratio of pulleys) = 2666 rpm maximum of all automations except the tool carrier spindle, the only one which has the ball bearings for high speed - 210 (motor torque) x 3 = 630 Nm in the spindle with a minimum of revolutions milling power 333, while the spindle revolutions from 0 to 9400 rpm (in In the case of the engine with the option of 10,000 rpm, the number of revolutions can reach up to 11,500 rpm without posing any problem for the spindle because it is lubricated, like the entire head, with air + oil spreading) and in this example of realization was obtained better result with the project of the head with automatic speed change integrated, achieving optimum result with the spindle ISO 50 of 22 kw (the same system is valid for other head sizes), thus reducing the expenses of the components, taking into account that the head is projected so that it can be mounted on existing machine tools, especially on older ones that surely work at low spindle revolutions, making a small change in the connection between two parts and that the change in speed is made up of a pair of sprockets that, through the hydraulic cylinder, connect with the low or high speed sprocket directly to the spindle, while this position is controlled by two connected sensors With machine control. 5. The milling head according to claims 1-4, characterized in that in the phase of speed change by cylinder there is the neutral zone where no gear wheel is connected to the other, and thus the position in which the transmission is disconnected 6. The milling head according to claims 1-5, characterized in that the hydraulic, pneumatic or electric cylinder used to move the speed clutch is controlled by two sensors that send information on the speeds at which the head is in control. of the machine