Spindle drive, actuator assembly, and method for producing a spindle drive

Abstract

A spindle drive for an actuator assembly of a vehicle brake is provided, with a spindle and a spindle nut mounted on the spindle, which forms an actuating carriage which can be displaced between a retracted and an extended position in order to apply a brake lining against a brake rotor. The spindle nut has a pressure-distributing element at an end of the spindle nut which is close to the brake lining, and a contact surface of the pressure-distributing element which faces away from the spindle is continuously or discontinuously annular. Furthermore, an actuator assembly with a spindle drive is provided. In addition, a method for producing a spindle drive is provided.

1 . A spindle drive for an actuator assembly of a vehicle brake, the spindle drive including a spindle and a spindle nut mounted on the spindle that forms an actuating carriage that can be displaced between a retracted and an extended position in order to apply a brake lining against a brake rotor, wherein the spindle nut has a pressure-distributing element at an end of the spindle nut that is close to the brake lining, and wherein a contact surface of the pressure-distributing element that faces away from the spindle is continuously or discontinuously annular. 
     
     
         2 . The spindle drive according to  claim 1 , wherein the annular contact surface is at least one of continuously or discontinuously circular, oval, or elliptical when viewed from the front. 
     
     
         3 . The spindle drive according to  claim 1 , wherein the pressure-distributing element has a frustoconical projecting collar that ends at the contact surface and widens out from an axial end of the spindle nut to the brake lining. 
     
     
         4 . The spindle drive according to  claim 3 , wherein, starting from the axial end of the spindle nut, the cross-section of the collar merges from a circular cross-section into an oval or elliptical cross-section. 
     
     
         5 . The spindle drive according to  claim 1 , wherein the contact surface has at least one depression, viewed in a side view. 
     
     
         6 . The spindle drive according to  claim 5 , wherein, in the case of an oval or elliptical contact surface, the depression is arranged in the region of the co-vertices. 
     
     
         7 . The spindle drive according to  claim 1 , wherein the contact surface runs at an angle to a friction surface of the brake lining, wherein two regions of the contact surface that are situated circumferentially opposite each other have opposite inclinations. 
     
     
         8 . The spindle drive according to  claim 1 , wherein the pressure-distributing element is made from metal and press-fitted or welded to the spindle nut, or in that the pressure-distributing element merges into the spindle nut as a single piece. 
     
     
         9 . The spindle drive according to  claim 1 , wherein the spindle drive is supported on an axial bearing in the brake caliper via the spindle, wherein the contact surface of the axial bearing with the spindle is a conical surface. 
     
     
         10 . The spindle drive according to  claim 1 , wherein the spindle drive is a ball screw. 
     
     
         11 . The spindle drive according to  claim 1 , wherein at least one cut-out, which leads to a thread of the spindle and which forms a mounting opening for the balls of the spindle drive, is present in a circumferential wall of the spindle nut. 
     
     
         12 .- 14 . (canceled) 
     
     
         15 . An actuator assembly for a vehicle brake, the actuator assembly including:
 a brake lining,   a brake rotor, and   a spindle drive, the spindle drive including with a spindle and a spindle nut mounted on the spindle that forms an actuating carriage that can be displaced between a retracted and an extended position in order to apply a brake lining against a brake rotor, wherein the spindle nut has a pressure-distributing element at an end of the spindle nut that is close to the brake lining, wherein a contact surface of the pressure-distributing element that faces away from the spindle is continuously or discontinuously annular, wherein the pressure-distributing element is arranged at an end of the spindle nut that faces the brake lining and the contact surface of the pressure-distributing element is in contact with a back plate of the brake lining in an extended position of the spindle nut and applies the brake lining to the brake rotor.   
     
     
         16 . The actuator assembly according to  claim 15 , wherein the annular contact surface is at least one of continuously or discontinuously circular, oval, or elliptical when viewed from the front. 
     
     
         17 . The actuator assembly according to  claim 15 , wherein the pressure-distributing element has a frustoconical projecting collar that ends at the contact surface and widens out from an axial end of the spindle nut to the brake lining. 
     
     
         18 . The actuator assembly according to  claim 17 , wherein, starting from the axial end of the spindle nut, the cross-section of the collar merges from a circular cross-section into an oval or elliptical cross-section. 
     
     
         19 . The actuator assembly according to  claim 15 , wherein the contact surface has at least one depression, viewed in a side view. 
     
     
         20 . The actuator assembly according to  claim 15 , wherein the contact surface runs at an angle to a friction surface of the brake lining, wherein two regions of the contact surface that are situated circumferentially opposite each other have opposite inclinations.