Cross wedge rolling mechanism, device and method for rolling laminated shaft

Abstract

A cross wedge rolling mechanism comprises a drive mechanism and two paralleled and opposed cross rolling moulds; the drive mechanism is in transmission connection with at least one cross rolling mould and drives the cross rolling mould to move; a contact surface in contact with the laminated shaft is disposed on the cross rolling moulds, wherein a pre-squeezing stripe protruding out of the contact surface is disposed on the contact surface of at least one cross rolling mould; a shaping wedge protruding out of the contact surface is disposed on the contact surface of at least one cross rolling mould; an included angle of an extending direction of the pre-squeezing stripe and a moving direction of the cross rolling mould is limited; the pre-squeezing stripe is disposed in front of the shaping wedge such that the laminated shaft sequentially runs over the pre-squeezing stripe and the shaping wedge during moulding.

1 . A cross wedge rolling mechanism for rolling a laminated shaft, which comprises a drive mechanism and two paralleled and opposed cross rolling moulds; the drive mechanism is in transmission connection with at least one cross rolling mould and drives the cross rolling mould to move; a contact surface in contact with the laminated shaft is disposed on the cross rolling moulds, wherein a pre-squeezing stripe protruding out of the contact surface is disposed on the contact surface of at least one cross rolling mould; a shaping wedge protruding out of the contact surface is disposed on the contact surface of at least one cross rolling mould; an included angle α of an extending direction of the pre-squeezing stripe and a moving direction of the cross rolling mould is less than 45°; the pre-squeezing stripe is disposed in front of the shaping wedge such that the laminated shaft can sequentially run over the pre-squeezing stripe and the shaping wedge during moulding. 
     
     
         2 . The cross wedge rolling mechanism for rolling a laminated shaft of  claim 1 , wherein the drive mechanism is a linear drive mechanism, and the cross rolling moulds are plate-type moulds; the linear drive mechanism is connected with at least one plate-type mould such that the two plate-type moulds can translate toward each other; the contact surface is used to abut against a support surface of the laminated shaft. 
     
     
         3 . The cross wedge rolling mechanism for rolling a laminated shaft of  claim 1 , wherein the drive mechanism is a rotation drive mechanism, and the cross rolling moulds are cross rolling rollers which move in opposite directions; the rotation drive mechanism is in transmission connection with at least one cross rolling roller and drives the cross rolling roller to rotate; the contact surface is a peripheral rolling arc surface of the cross rolling rollers, and the pre-squeezing stripe extends along a peripheral direction of the rolling arc surface. 
     
     
         4 . The cross wedge rolling mechanism for rolling a laminated shaft of  claim 3 , wherein at least one of the cross rolling rollers comprises a roller body and a cross rolling arc plate detachably mounted on a cylindrical surface of the roller body; the cross rolling arc plate partially wraps the roller body along a circumferential direction of the cross rolling roller and protrudes out of the cylindrical surface of the roller body; the rolling arc surface is disposed on the cross rolling arc plate. 
     
     
         5 . The cross wedge rolling mechanism for rolling a laminated shaft of  claim 4 , wherein the radiuses of the two cross rolling rollers are R 1  and R 2  respectively, a distance between the two axes of the two cross rolling rollers is L, and an outer diameter of the laminated shaft is D 1 , and R 1 +R 2 +D 1 ≤L≤H0+R 1 +R 2 +D 1 ; when only one cross rolling roller comprises the cross rolling arc plate, the H0 is a height that the rolling arc surface in the cross rolling arc plate protrudes out of the cylindrical surface of the roller body; when each of two cross rolling rollers comprises the cross rolling arc plate, the H0 is a sum of the heights that the two rolling arc surfaces protrude out of the cylindrical surfaces of the corresponding roller bodies. 
     
     
         6 . The cross wedge rolling mechanism for rolling a laminated shaft of  claim 3 , wherein distances of the two rolling arc surfaces from the axes of the corresponding cross rolling rollers are L 1  and L 2  respectively, and the distance between the two axes of the two cross rolling rollers is L, and the outer diameter of the laminated shaft is D 1 , and L 1 +L 2 +D 1 ≤L;
 when the pre-squeezing stripe is disposed on the rolling arc surface of only one cross rolling roller, a height that the pre-squeezing stripe protrudes out of the corresponding rolling arc surface is H1, and H1+L 1 +L 2 +D 1 ≥L; 
 when the pre-squeezing stripe is disposed on the rolling arc surface of each of the two cross rolling rollers, the heights that the two pre-squeezing stripes protrude out of the corresponding rolling arc surfaces are H1 and H2, and H1+H2+L 1 +L 2 +D 1 ≥L; 
 when the shaping wedge is disposed on the rolling arc surface of only one cross rolling roller, the height that the shaping wedge protrudes out of the corresponding rolling arc surface is H3, and H3+L 1 +L 2 +D 1 ≥L; 
 when the shaping wedge is disposed on the rolling arc surface of each of the two cross rolling rollers, the heights that the two shaping wedges protrude out of the corresponding rolling arc surfaces are H3 and H4, and H3+H4+L 1 +L 2 +D 1 ≥L. 
 
     
     
         7 . The cross wedge rolling mechanism for rolling a laminated shaft of  claim 3 , wherein the pre-squeezing stripe extends helically along a peripheral direction of the cross rolling roller, and a helical angle of the pre-squeezing stripe is β, where β=90°−α and 80° β 90°. 
     
     
         8 . The cross wedge rolling mechanism for rolling a laminated shaft of  claim 1 , wherein the height that the shaping wedge protrudes out of the corresponding contact surface is greater than the height that the pre-squeezing stripe protrudes out of the corresponding contact surface. 
     
     
         9 . The cross wedge rolling mechanism for rolling a laminated shaft of  claim 1 , wherein 0° α 10°. 
     
     
         10 . The cross wedge rolling mechanism for rolling a laminated shaft of  claim 9 , wherein the pre-squeezing stripes on the two cross rolling moulds are mutually matched so that helical grooves formed by the two pre-squeezing stripes on the laminated shaft are overlapped or connected head to tail. 
     
     
         11 . The cross wedge rolling mechanism for rolling a laminated shaft of  claim 1 , wherein multiple pre-squeezing stripes are disposed, and the multiple pre-squeezing stripes are paralleled and spaced apart. 
     
     
         12 . The cross wedge rolling mechanism for rolling a laminated shaft of  claim 11 , wherein multiple pre-squeezing stripes form a pre-squeezing stripe group with a width less than or equal to a width of the widest span of the shaping wedge. 
     
     
         13 . The cross wedge rolling mechanism for rolling a laminated shaft of  claim 1 , wherein a front end of the pre-squeezing stripe is provided with a transitional stripe with its height increasing from front to back. 
     
     
         14 . The cross wedge rolling mechanism for rolling a laminated shaft of  claim 1 , wherein the shaping wedge comprises a shaping front portion and a shaping rear portion at a rear side of the shaping front portion; a width of the shaping front portion increases from an end away from the shaping rear portion to an end close to the shaping rear portion; a front side of the shaping front portion is provided with a transitional portion with a height increasing from an end away from the shaping front portion to an end close to the shaping front portion. 
     
     
         15 . A cross wedge rolling device for rolling the laminated shaft, wherein the device comprises a fixing frame and the cross wedge rolling mechanism of  claim 2 ; one of the two plate-type moulds is fixed to the fixing frame and the other is slidably connected with the fixing frame; the two plate-type moulds are disposed up and down, and the linear drive mechanism is mounted on the fixing frame. 
     
     
         16 . A cross wedge rolling device for rolling the laminated shaft, wherein the device comprises a machine frame, a positioning assembly and the cross wedge rolling mechanism of  claim 3 ; the two cross rolling rollers are rotatably connected to the machine frame, the positioning assembly and the rotation drive mechanism are mounted on the machine frame, and the positioning assembly is disposed between the two cross rolling rollers. 
     
     
         17 . The cross wedge rolling device for rolling the laminated shaft of  claim 16 , wherein the positioning assembly comprises a first clamping plate and a second clamping plate extending along an axial direction of the cross rolling rollers; the first clamping plate and the second clamping plate are disposed in a spacing between the two cross rolling rollers and mounted on the machine frame; an avoiding gap is reserved between the first clamping plate and the cross rolling rollers, and an avoiding gap is reserved between the second clamping plate and the cross rolling rollers; a positioning groove extending along an axial direction of the cross rolling rollers is disposed between the first clamping plate and the second clamping plate; at least one end of the positioning groove along the axial direction of the cross rolling rollers is disposed as opening. 
     
     
         18 . A cross wedge rolling method, wherein the method comprises the following steps based on the cross wedge rolling device of  claim 15 :
 at step S 100 , the inner and outer shafts of the laminated shaft prior to rolling are assembled by a press machine through interference fit and then welding is performed at ends;   at step S 200 , after completion of the welding, the assembled laminated shaft is sent into a heating furnace for heating;   at step S 300 , the heated laminated shaft is sent into the cross wedge rolling device and the two plate-type moulds tightly clamp the laminated shaft;   at step S 400 , the two plate-type moulds are moved toward each other to enable the laminated shaft to sequentially run over the pre-squeezing stripe and the shaping wedge; when the laminated shaft runs over the pre-squeezing stripe, an indentation is generated on the outer surface of the outer shaft while the indentation is transferred to the inner shaft; when the laminated shaft runs over the shaping wedge, the indentation on the outer surface of the outer shaft is rolled flat under the effect of the shaping wedge; at the same time, the indentation on the outer surface is further transferred under the effect of the shaping wedge to the combination interface of the inner and outer shafts; the finally-rolled laminated shaft has a smooth and flat outer surface, and the combination interface of the inner and outer shafts has wave characteristics;   at step S 500 , the formed laminated shaft is taken out.   
     
     
         19 . A cross wedge rolling method, wherein the method comprises the following steps based on the cross wedge rolling device of  claim 17 :
 at step S 100 , the inner and outer shaft prior to rolling are assembled by a press machine through interference fit and then welding is performed at ends;   at step S 200 , after completion of the welding, the assembled laminated shaft is sent into a heating furnace for heating;   at step S 300 , the heated laminated shaft is sent into the cross wedge rolling device and positioned inside the positioning assembly;   at step S 400 , the rotation drive mechanism drives the cross rolling rollers to rotate to enable the laminated shaft to sequentially run over the pre-squeezing stripe and the shaping wedge; when the laminated shaft runs over the pre-squeezing stripe, an indentation is generated on the outer surface of the outer shaft while the indentation is transferred to the inner shaft; when the laminated shaft runs over the shaping wedge, the indentation on the outer surface of the outer shaft is rolled flat under the squeezing effect of the shaping wedge; at the same time, the indentation on the outer surface is further transferred under the effect of the shaping wedge to the combination interface of the inner and outer shafts; the finally-rolled laminated shaft has a smooth and flat outer surface, and the combination interface of the inner and outer shafts has wave characteristics;   at step S 500 , the formed laminated shaft is taken out from the positioning assembly.