GB2319488A

GB2319488A - Double-arm vertical milling machine

Info

Publication number: GB2319488A
Application number: GB9719323A
Authority: GB
Inventors: Momoitio Ignacio Alvarez
Original assignee: Noran SL
Current assignee: Noran SL
Priority date: 1996-10-11
Filing date: 1997-09-12
Publication date: 1998-05-27
Also published as: DE19725670A1; ES2146138B1; FR2754480A1; GB9719323D0; ES2146138A1; FR2754480B3

Abstract

The machine has a frame (2) fastened to the centre of a worktable (1), a horizontal guide (3) set up on the frame in order for the sliding bracket (4) to move, being driven by an engine (5). Meanwhile two vertical arms (6) are fitted onto the said bracket (4), one on each half, which are driven by a single intermediate motor (7), along with a set of gears (8) fitted with a clutch which transmits movement to only one of the arms (6) or to both arms simultaneously in the same direction or in opposite directions. Each of the arms (6) is fitted with a tool-holder (9), which may be displaced vertically with the aid of the engine (11), so that the tools (12) may operate simultaneously in order to obtain two identical or symmetric pieces, or in order to work individually.

Description

2319488

-1DESCRIPTION DOUBLE-ARM VERTICAL MILLING MACHINE

The present invention relates to a double-arm vertical milling machine.

More particularly, the present invention relates to a double-arm vertical milling machine, capable of milling two pieces simultaneously, be they identical or symmetric pieces, or of carrying out a milling and a digitized operation at the same time, in which each of its operating cutting-heads is able to move according to a system of "X, 11Y11, 11W Cartesian coordinates. It has a very simple structure with a high operating efficiency.

Milling machines normally have a built-in arm upon which the precise tool is fitted in order to eliminate the chippings, this is complemented with a second arm that acts as a feeler, making it impossible to simultaneously mill two pieces on this type of machine.

There is also a double-head milling machine, which is described in the Spanish use model under application number 8802993. It is characterized by the fact that one of the cutting-heads is fitted onto the main shaft and may be moved up or down relative to the machine frame, meanwhile the other cutting-head is fitted onto the moveable frame which is precisely guided on the aforementioned main shaft and shifted in an axial direction to the shaft and to the abovementioned first cutting-head.

This solution is more closely related to the conjunction of two standalone milling machines, than to a double cutting-head machine, since its performance is similar to that of two stand-alone machines and not that of a single machine with a dual operation.

In order to resolve this problem, a vertical milling machine was proposed and patented by the Applicant, in which a bracket is used which moves in a transverse direction over a frame with the help of an engine. The bracket has two arms fitted to it and can be displaced along it in a longitudinal direction with the help of their respective engines, that is, perpendicular to the bracket. Each of the arms permit the corresponding tool to be placed in them which may also be displaced vertically with the help of another engine and also provided with the necessary tool rotating engine. This allows each of the tools to move along the "X", I'V' and 11W axes mentioned above.

This gives it the possibility of simultaneously milling two identical or symmetric pieces therefore saving time and improving quality. it also allows one of the arms to carry out a digitized job while the other arm simultaneously machines or mills another piece.

The aim of the present invention, commencing with the structure of the aforementioned double-arm vertical milling machine, has been to appreciably perfect the double-arm vertical milling machine in order to achieve quite a noticeable simplified structure, along with an improvement in its operational capacity.

According to the present invention there is provided a double-arm vertical milling machine, comprising a platform or worktable upon which is fastened a middle and fixed frame with an upper guide in order to move a transverse bracket upon which a pair of vertical arms are assembled for carrying their respective tools, the arms being movable transversely upon the bracket, while the tools are movable vertically in the arms, the arms being movable along the bracket by a single engine which, through a set of gears supplies movement to only one of two transmission shafts for movement towards one of the arms, or to both shafts, in this latter case in the same direction or in opposite directions, according to whether two identical or symmetric pieces are needed.

As regards the initial aim ie a simplified construction and according to one of the features of the invention, both of the engines for the longitudinal displacement of the arms upon the single bracket. Those used in order to move the tools along the 11Y11 axis, -4have been replaced by a single engine located in the centre part of the bracket, exactly on top of the frame. The engine is directly coupled to one of the shafts fitted onto the bracket, which corresponds to one of the tools, as well as to one of the gears, which, through a clutch device, may be connected directly to the gear fastening the milling machine's other axis, or if it were to be done in conjunction with an intermediate gear, so that when the clutched gear is isolated only one of the milling machine's tools would be in operation in order to obtain one single piece. When the said gear is directly connected to the other shaft both tools operate simultaneously allowing two symmetric pieces to be turned out. whereas when the connection is carried out through a third intermediate and swivel-mounted gear, both shafts rotate in the same direction in order to produce two identical pieces.

Preferably, the said bracket, mounted transversely upon the middle frame, is fastened at the ends to each of the struts associated to the worktable via guides which allow them to move. When the said bracket slides along the frame, so that the bracket finishes on a second frame, fitted as a sliding piece over the middle and fixed frame. This prevents vibrations from occurring and improves the working condition of the machine.

Further, one of the struts included in the mobile frame is preferably provided with a tracer (visualizer) in order to control the progress of the work.

The present invention will now be further described, by way of example, with reference to the accompanying drawings, in which:- Fig. 1 is a perspective drawing illustrating a doublearm vertical milling machine manufactured according to the present invention; Fig. 2 is a side elevation illustrating the set of gears with which, and using a single engine, the movement of the two axes or bracket sectors are transmitted, in order for the tool-holder arms to slide upon it; Fig. 3 shows the details of a front elevation of the set of gears represented in the Fig.'2, in operating position in order to obtain two identical pieces; Fig. 4 is similar to Fig. 3 except that the transmission operating position is set in order to obtain two symmetric pieces; and Fig. 5 is similar to Fig. 3 and 4 except that only one of the machine arms is operational in order to mill a single piece.

As can be seen in the Figures and especially in Fig. 1, we can observe how the vertical milling machine proposed includes a platform or worktable (1) upon which a fixed bracket (2) is placed in the centre and transversely with a guide (3) on its upper section in order to slide along the "X" axis of the frame (4) in collaboration with an engine (5). The respective arms (6-61) slide upon the guides of the said frame (4), in collaboration with a single and intermediate engine (7) and a set of gears (8), which will be described below, in order to obtain movement along the 11Y11 axis. Meanwhile movement along the "Z" axis is achieved due to the tool-holder heads (9) being able to move vertically in the said arms (6-61) in collaboration with each of their respective engines (10). While the engines (11) are fitted in the arms (6-61) allowing the tools (12) the necessary rotating (swivel) movement in order to carry out their milling operation.

The frame (4), as mentioned above, receives both struts (13-131) through its free end provided with the means for coupling the guides (14) to the outer edges on their lower section and which correspond to the worktable (1). This transforms the said frame (4) into a mobile frame which gives the whole unit greater stability, absorbs vibrations and allows for a faster working speed. Any of these two struts (13) can be used as a support element for a tracer (visualizer) (15) allowing the work being carried out to be supervised.

If we go back again to the set of gears (8) and as can be observed especially in figures 2 and 3, it Is set up upon one main gear (16) assembled in such a manner that it enables it to slide along an extension (17) of the shaft (18) which corresponds to one of the halves of the bracket (4). This shaft receives movement directly from the engine (7), via belt (19) or any other suitable means of transmission, so that the said shaft (18) is kept in movement all the time the engine (7) is in operation.

The other shaft (18% which corresponds to the other half of the bracket (4), after a cardan transmission (20), is then connected onto a second gear (2 1), which is identical to gear (16) and laterally displaced to it, to such an extent that the said gears become tangent and can be coupled or decoupled, that is clutched and declutched by sliding the main gear (16) over the extension (17) of the shaft (18) between the end position which appear in figures 4 and 5.

More specifically the position of the clutch which appears in figure 4 for gears (16) and (21) the movement is transmitted to the secondary shaft (18') rotating in the opposite direction to that of the main shaft (18). The above process achieves a simultaneous machining of two symmetric pieces, whereas the position illustrated in figure 5, in which gears (16) and (2 1) are declutched so that only the main shaft (18) moves, this being an operating position in order to obtain one single piece.

Finally, and in order to simultaneously obtain two identical pieces, which means that movement of shafts (18) and (18) must be in the same direction, a third gear (22) has been provided, set up upon a rocker beam (23), which can be activated by any suitable means between the end positions represented by a continuous and dotted line in figure 2. This means that from the no-operation situation shown by the dotted line, this third gear (22) is capable of coupling with crears (16) and (2 1), as a transmission bridge between both of them in accordance to figure 3. Figure 3 shows us that the said gears (16) and (2 1) are longitudinally out of phase, with which the desired transmission movement is achieved from the main shaft (18) to the secondary shaft (18% the movement being in the same direction in order to obtain two identical pieces.

A more in depth description is not considered to be necessary for an expert in this field to understand the scope of the invention and the advantages derived from it.

The materials, shape, size and lay out of the elements are always susceptible to change as long as this does not change the essential objective of the invention.

The terms in which this report has been written should be considered in an ample and not in a limiting sense.

Claims

- 9 CLAIMS

1. A double-arm vertical milling machine, comprising a platform or worktable upon which is fastened a middle and fixed frame with an upper guide in order to move a transverse bracket upon which a pair of vertical arms are assembled for carrying their respective tools, the arms being movable transversely upon the bracket, while the tools are movable vertically in the arms, the arms being movable along the bracket by a single engine which, through a set of gears supplies movement to only one of two transmission shafts for movement towards one of the arms, or to both shafts, in this latter case in the same direction or in opposite directions, according to whether two identical or symmetric pieces are needed.

2. A double-arm vertical milling machine, as claimed in claim 1, in which the said engine which can move the arms along the bracket, acts directly and permanently upon one of the shafts, which is provided with an extension upon which a main gear can be moved longitudinally and susceptible to being isolated or coupled to a second gear which through a cardan transmission connects the end of the other shaft a third gear, mounted upon a rocker-arm which allows the simultaneous coupling/decoupling of the third gear to the main and secondary gears, collaborating when symmetric pieces are required.

3. A double-arm vertical milling machine, as 1,11 claimed in claim 1 or claim 2, in which the bracket for the tool-holder arms is fixed at its free ends by two struts which are linked by their lower end sections to guides placed from an operating point of view on the edges of the worktable, so that the said struts turn the bracket into a second, mobile frame which prevents possible vibrations which may be generated from the operating components of the machine.

4. A double-arm vertical milling machine, as claimed in claim 3, in which at least one of the said struts which stabilize the bracket, constitutes the base for a visualizer used in order to supervise the work to be carried out by the machine.

5. A double-arm vertical milling machine, constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.