Device for calibrating and lightening the weight of crankshafts

Abstract

A device for lightening the weight of vehicle components includes a tooling provided with a seat wherein the component is formed and a plurality of moveable bodies, which are moveable between an initial position and a final position, such that in the final position one end of each moveable body penetrates the seat of the tooling to form a cavity to lighten the weight of a component of the vehicle, wherein at least one of the moveable bodies can move laterally. Such device allows lightening the weight in a more simple and productive way than in currently known systems. This is achieved because the moveable bodies do not interfere with each other during the movement thereof, such that the lightening process can be done in a single blow during a forging procedure.

Claims

1. A device for calibrating and lightening the weight of a crankshaft, said device comprising: a tooling provided with a seat wherein the crankshaft is formed; a plurality of moveable bodies that are moveable between an initial position and a final position, wherein in the final position one end of each moveable body extends inwardly from said seat of said tooling to form a cavity to lighten the weight of the crankshaft; a plurality of wedges having inclined planes, wherein said movable bodies are mounted at said wedges and are movable diagonally with respect to said seat of said tooling; and an intermediate piece mounted on one of said wedges and having a pair of angled body support surfaces; wherein at least two of said moveable bodies are mounted along said intermediate piece at respective ones of said angled body support surfaces and have respective longitudinal axes arranged parallel to said angled body support surfaces, wherein said at least two of said moveable bodies are configured to move transversely in relation to their respective longitudinal axes; and wherein said tooling comprises a lower edge piece in which said moveable bodies are mounted, wherein said lower edge piece is moveable with respect to a frame of said device.

2. The device according to claim 1, wherein at least one or all of said moveable bodies comprise a lowered portion close to said end that forms said cavity to lighten the weight of the crankshaft, said lowered portion defining a projecting portion at said end, said projecting portion being that which forms said cavity.

3. The device according to claim 2, wherein said projecting portion has rounded edges.

4. The device according to claim 2, wherein said lowered portion has rounded edges.

5. The device according to claim 2, wherein said projecting portion has a substantially semicircular form in a plan view.

6. The device according to claim 2, wherein said projecting portion has a substantially rectangular form with its smaller sides curved in a plan view.

7. The device according to claim 2, wherein said moveable bodies mounted on said intermediate piece comprise bevels, said moveable bodies being substantially in contact with each other by means of said bevels when at said initial position, and wherein said bevels are arranged on said ends provided with said projecting portions.

8. The device according to claim 1, wherein at least one of said moveable bodies comprises an inclined surface complementary to said inclined plane of one of said wedges.

9. The device according to claim 1, wherein said moveable bodies mounted on said intermediate piece comprise bevels, said moveable bodies being substantially in contact with each other by means of said bevels when at said initial position.

10. The device according to claim 1, wherein said wedges are fixedly mounted to said frame of said device, such that the movement of said lower edge piece causes the movement of said moveable bodies from said initial position to said final position thereof.

11. The device according to claim 1, wherein each moveable body is associated with a spring that presses said moveable body back to its initial position.

12. A device for calibrating and lightening the weight of a crankshaft, said device comprising: a tooling provided with a seat wherein the crankshaft is formed; a plurality of moveable bodies that are moveable between an initial position and a final position, wherein in the final position one end of each moveable body comprises a projecting portion and extends inwardly from said seat of said tooling to form a cavity to lighten the weight of the crankshaft; a plurality of wedges having inclined planes, wherein said movable bodies are mounted at said wedges and are movable diagonally with respect to said seat of said tooling; and an intermediate piece mounted on one of said wedges; wherein at least two of said moveable bodies are mounted along said intermediate piece and have respective bevels that contact one another in said initial position, and are movable apart to separate their bevels in response to movement of said intermediate piece toward said seat; and wherein said tooling comprises a lower edge piece in which said moveable bodies are mounted, wherein said lower edge piece is moveable with respect to a frame of said device.

13. The device according to claim 12, wherein all of said moveable bodies comprise one of said projecting portions and a lowered portion close to said end that forms said cavity to lighten the weight of the crankshaft, said lowered portion defining said projecting portion at said end, said projecting portion being that which forms said cavity.

14. The device according to claim 12, wherein said projecting portion has a substantially semicircular form in a plan view.

15. The device according to claim 12, wherein each of said projecting portions has a substantially rectangular form with its smaller sides curved in a plan view.

16. The device according to claim 12, wherein each of said projecting portions has rounded edges and each of said lowered portions has rounded edges.

17. The device according to claim 12, wherein at least one of said moveable bodies comprises an inclined surface complementary to said inclined plane of a respective one of said wedges.

18. The device according to claim 12, wherein said wedges are fixedly mounted to said frame of said device, such that the movement of said lower edge piece causes the movement of said moveable bodies from said initial position to said final position thereof.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) For the purpose of helping to make the foregoing description more readily understandable, it is accompanied by a set of drawings which, schematically and by way of illustration and not limitation, represent an embodiment.

(2) FIG. 1 is a schematic perspective view of the device for calibrating and lightening the weight of crankshafts according to the present invention;

(3) FIGS. 2 and 3 are perspective views of two types of moveable bodies used by the device for calibrating and lightening the weight of crankshafts according to the present invention;

(4) FIG. 4 is a schematic plan view of a crankshaft indicating the initial position of the moveable bodies of the device for calibrating and lightening the weight of crankshafts according to the present invention; and

(5) FIG. 5 is a schematic plan view of a crankshaft indicating the final position of the moveable bodies of the device for calibrating and lightening the weight of crankshafts according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(6) It must first be stated that this preferred embodiment is described in relation to a crankshaft for a vehicle motor.

(7) As was previously mentioned, on a crankshaft it is advantageous to remove material on the contiguous chamfers of each crankpin. This is because they are areas that do not experience significant stresses and do not have any specific function.

(8) The device according to the present embodiment comprises a tooling 10, formed by a lower edge piece 12 and an upper edge piece (not shown in the figures), as will be described further on. The tooling 10 defines a seat 11 in the shape of the component that will be manufactured, such as a crankshaft 14.

(9) For forming the cavities in the component, the device according to the present embodiment comprises a plurality of moveable bodies 1a, 1b, which can move from an initial position (FIG. 4) in which the moveable bodies 1a, 1b are outside of the seat 11, to a final position (FIG. 5), in which one of the two ends of each moveable body 1a, 1b is on the inside of the seat 11 to form the cavities when the component is manufactured 14.

(10) In the case of crankshafts, the component 14 has two types of chamfers. For this reason, it is necessary to design two types of cavities, adapting them to the form of each chamfer and, therefore, the device according to the present embodiment will comprise two types of moveable bodies, respectively identified by the references 1a and 1b, in other words, first moveable bodies 1a and second moveable bodies 1b.

(11) The first moveable bodies 1a can move longitudinally along the longitudinal axes A.sub.a thereof and the second moveable bodies 1b can move laterally, in other words, perpendicular with respect to the longitudinal axes A.sub.b thereof, such as shown in FIGS. 4 and 5.

(12) FIGS. 2 and 3 show a first moveable body 1a and a second moveable body 1b, respectively.

(13) In both cases the moveable body 1a, 1b comprises a respective lowered portion 2a, 2b close to one end of the body. This lowered portion 2a, 2b defines a respective projecting portion 3a, 3b, which forms the respective cavity in the component 14.

(14) As can be seen in FIG. 2, in the case of the first moveable body 1a, the first projecting portion 3a has a substantially rectangular plan form with the smaller sides thereof curved, while in the case of the second moveable body 1b, the projecting portion 3a has a substantially semicircular plan form. Moreover, in both cases the edges are rounded to prevent sharp edges.

(15) In the case that the first moveable bodies 1a, the same are placed just as shown in the figures. The first moveable bodies 1a are mounted on first wedges 4a for diagonal movement of the first moveable bodies 1a, as will be described below. To this end, the first moveable bodies 1a comprise an inclined surface 6 that is in contact with the respective first wedge 4a.

(16) On the other hand, according to the embodiment shown, two second moveable bodies 1b are placed in a centered position as shown in the figures. These second moveable bodies 1b are mounted on an intermediate piece 5, which, in turn is mounted on a second wedge 4b. In the initial position (FIG. 4) the second moveable bodies 1b are substantially in contact with one another by means of a bevel 7, while in the final position (FIG. 5) they are separated.

(17) The mounting of the device according to the present embodiment is done in the following way. Firstly, a lower edge piece 12 is mounted for calibration.

(18) Then, springs 15 are mounted which return the moveable bodies 1a, 1b to their initial positions. Then, the moveable bodies 1a, 1b and the intermediate piece 5 are mounted in their positions.

(19) Then, locks for the lower edge piece 12 and a swage block 17, which provides rigidity to the assembly, are mounted. Lastly, the assembly is placed on a frame 16 with the wedges 4a, 4b integrated.

(20) The calibration process, which is done by means of the device according to the present embodiment, is the last operation in the manufacturing process of the crankshaft. It must be stated that before the calibration process, during which the weight of the crankshaft is calibrated and lightened, other stages are performed, which are not described in the present embodiment because they are evident for a person skilled in the art and do not form part of the present embodiment.

(21) The process of calibrating and lightening the weight of the components is the following. Firstly, the upper edge piece lowers until making contact with the lower edge piece 12 (which until this moment was immobile) and closes the device, enclosing the component 14. At this point, both edge pieces move downward in an integral way as a single block.

(22) This movement as a block is possible thanks to the fact that the lower edge piece 12 is placed on a group of cylinders (not shown in the figure), which have a spring function and allow this effect.

(23) The lower edge piece 12 has the moveable bodies secured to the same by the springs, moveable bodies which penetrate the aforementioned crankshaft chamfers, forming the cavities.

(24) The movement of these moveable bodies can be divided into two parts: Movement with respect to the tooling: the springs that secure the moveable bodies to the tooling and restrict their movement with respect to the same to the XY plane (considering that the assembly of the upper and lower edge pieces moves along the Z axis). Movement with respect to the absolute coordinate axis: during the movement of the assembly, each moveable body moves on a respective wedge 4a, 4b that is immobile. These wedges 4a, 4b make the moveable bodies 1a, 1b move diagonally. The vertical component of that movement is equal to the movement of the edge pieces, and the horizontal component of the movement is equal to the movement with respect to the tooling.

(25) When the cavities have been formed, the cylinders make the assembly of the edge pieces return to the initial position thereof. The springs 15 that secure the moveable bodies 1a, 1b also return them to their initial position.

(26) Despite the fact that reference has been made to a specific embodiment of the invention, it is evident for a person skilled in the art that numerous variations and changes may be made to the device described, and that all the aforementioned details may be substituted by other technically equivalent ones, without detracting from the scope of protection defined by the attached claims. Thus, it will be appreciated that changes and modifications in the specifically-described embodiments may be carried out without departing from the principles of the present invention, which is intended to be limited only by the scope of the appended claims as interpreted according to the principles of patent law including the doctrine of equivalents.