Scissor lift with electric actuator

Abstract

A scissor lift includes a base, a platform, a lift assembly, and a linear actuator coupled to the lift assembly. The lift assembly includes a first support member pivotally coupled to a second support member and a third support member pivotally coupled to a fourth support member. The linear actuator includes a housing, a screw coupled to the housing, an extending member slidably coupled to the housing, and an electric motor coupled to the housing and configured to drive the screw to move the extending member relative to the housing. The housing includes a first mount coupled to the first support member and configured to rotate relative to the first support member about a first lateral axis. The extending member includes a second mount coupled to the third support member and configured to rotate relative to the third support member about a second lateral axis.

What is claimed is: 
     
         1 . A scissor lift, comprising:
 a base;   a platform configured to support a load;   a lift assembly having a first end coupled to the base and a second end coupled to the platform, the lift assembly including:
 a first support member pivotally coupled to a second support member; and 
 a third support member pivotally coupled to a fourth support member; and 
   a linear actuator coupled to the lift assembly, the linear actuator including:
 a housing including a first mount coupled to the first support member and configured to rotate relative to the first support member about a first lateral axis; 
 a screw coupled to the housing; 
 an extending member slidably coupled to the housing, the extending member including a second mount coupled to the third support member and configured to rotate relative to the third support member about a second lateral axis; and 
 an electric motor coupled to the housing and configured to drive the screw to move the extending member relative to the housing. 
   
     
     
         2 . The scissor lift of  claim 1 , wherein the lift assembly further includes a bracket coupling the first mount to the first support member. 
     
     
         3 . The scissor lift of  claim 2 , wherein the bracket offsets the first mount relative to the first support member such that the first lateral axis does not intersect the first support member. 
     
     
         4 . The scissor lift of  claim 3 , wherein the bracket is a first bracket, wherein the lift assembly further includes a second bracket coupling the second mount to the third support member, and wherein the second bracket offsets the second mount relative to the third support member such that the second lateral axis does not intersect the third support member. 
     
     
         5 . The scissor lift of  claim 1 , wherein the third support member and the fourth support member extend above the first support member and the second support member. 
     
     
         6 . The scissor lift of  claim 5 , wherein the lift assembly further includes a first bracket coupling the first mount to the first support member and a second bracket coupling the second mount to the third support member. 
     
     
         7 . The scissor lift of  claim 6 , wherein the first bracket extends below the first support member, and wherein the second bracket extends above the third support member. 
     
     
         8 . The scissor lift of  claim 1 , wherein the housing has a first end defining an aperture that receives the extending member and a second end opposite the first end of the housing, and wherein the first mount is offset from the second end of the housing. 
     
     
         9 . The scissor lift of  claim 8 , wherein the housing includes an elongated member that defines the aperture and a gearbox coupling the electric motor to the elongated member, and wherein the elongated member and the electric motor both extend away from the gearbox in a first direction. 
     
     
         10 . The scissor lift of  claim 1 , wherein the extending member is centered about and extends along an axis of extension, and wherein the electric motor is offset from the axis of extension. 
     
     
         11 . The scissor lift of  claim 1 , wherein the linear actuator further includes:
 a brake configured to selectively limit movement of the extending member relative to the housing;   a cable coupled to the brake; and   a handle coupled to the cable, wherein the cable is configured to disengage the brake to permit the movement of the extending member relative to the housing in response to a user interacting with the handle.   
     
     
         12 . The scissor lift of  claim 11 , wherein the linear actuator further includes a bracket coupled to the electric motor and supporting the cable. 
     
     
         13 . The scissor lift of  claim 11 , wherein the handle is coupled to a first end portion of the cable, further comprising a bracket coupling the first end portion of the cable to the base. 
     
     
         14 . The scissor lift of  claim 11 , wherein the brake is configured to selectively prevent lowering of the platform, and wherein the cable is configured to disengage the brake to permit the lowering of the platform in response to the user pulling the handle. 
     
     
         15 . The scissor lift of  claim 11 , wherein the linear actuator further includes a gearbox coupling the electric motor to the screw, wherein the gearbox extends along a first side of the electric motor, and wherein the brake extends along a second side of the electric motor opposite the first side. 
     
     
         16 . The scissor lift of  claim 1 , wherein the lift assembly further includes a fifth support member pivotally coupled to a sixth support member, wherein the fifth support member has a first end portion pivotally coupled to the first support member and a second end portion pivotally coupled to the third support member. 
     
     
         17 . A scissor lift, comprising:
 a base;   a platform configured to support a load;   a lift assembly coupled to the base and the platform, the lift assembly including:
 a first support member pivotally coupled to a second support member; and 
 a third support member pivotally coupled to a fourth support member; and 
   a linear actuator configured to control the lift assembly to move the platform between a raised position and a lowered position, the linear actuator including:
 a housing pivotally coupled to the first support member, the housing including a first portion and a second portion extending substantially perpendicular to the first portion; 
 an extending member received within the first portion and pivotally coupled to the third support member; and 
 an electric motor coupled to the second portion of the housing and configured to cause the extending member to move along an axis of extension, the electric motor being offset from the axis of extension, 
 wherein the electric motor and the first portion extend above the second portion of the housing at least when the platform is in the raised position. 
   
     
     
         18 . The scissor lift of  claim 17 , wherein the housing is configured to rotate relative to the first support member about a lateral axis that extends between the first portion and the second portion of the housing. 
     
     
         19 . A scissor lift, comprising:
 a base;   a platform configured to support a load;   a lift assembly having a first end coupled to the base and a second end coupled to the platform, the lift assembly including:
 a first support member pivotally coupled to a second support member; 
 a first bracket coupled to the first support member and extending below the first support member; 
 a third support member pivotally coupled to a fourth support member; and 
 a second bracket coupled to the third support member and extending above the third support member; 
   a linear actuator coupled to the lift assembly, the linear actuator including:
 a housing including an elongated member and a first mount coupled to the first support member, wherein the housing is configured to rotate relative to the first support member about a first lateral axis that does not intersect the first support member; 
 a screw coupled to the housing; 
 an extending member received within the elongated member, the extending member including a second mount coupled to the third support member, wherein the extending member is configured to rotate relative to the third support member about a second lateral axis that does not intersect the third support member; 
 an electric motor coupled to the housing and configured to drive the screw to move the extending member relative to the housing, wherein the electric motor is offset from the extending member; 
 a gearbox coupling the electric motor to the screw, wherein the elongated member and the electric motor both extend away from the gearbox in a first direction; and 
 a brake configured to selectively prevent lowering of the platform; 
   a handle movably coupled to the base; and   a cable coupling the handle to the brake.   
     
     
         20 . The scissor lift of  claim 19 , wherein the first mount is positioned between the gearbox and the elongated member.