RU2471100C1 - Hydrostatic lead screw-nut transmission - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: hydrostatic screw-nut transmission includes a screw and a nut with trapezoidal thread. Pockets are provided on side surfaces of screw thread of nut. The above pockets are connected by means of throttle channels to distributing channels, which are connected through throttles to supply line. Pump arranged in oil bath and non-return valve are connected to supply line through filter. Capacity that is hydraulically connected to oil bath serves as drain bath for working medium.

EFFECT: increasing efficiency, service life and improving transfer reliability.

2 dwg

Description

The invention relates to the field of mechanical engineering, namely to transmission systems with the use of lubricant, and can be used in transport and in sports vehicles.

Closest to the claimed object is the transmission mechanism of the lead screw-nut, which converts the rotational movement of the screw into a linear translational movement of the nut associated with the support of the machine (AS USSR No. 976412, F02M 59/04 - prototype). Also known mechanisms of the screw-nut rolling and sliding.

The disadvantages of the known objects is that screw slip pairs due to large losses when sliding in the thread and the associated wear are replaced by screw rolling pairs, which have low friction losses, high efficiency, in addition, they completely eliminated the gaps in the thread in the result of creating a preload. Replacement of sliding friction by rolling friction in a screw pair is possible either by using instead of a nut rollers freely rotating on their axes, or by using rolling bodies (balls). Balls are rolled in the grooves of the lead screw and nut, but in ball pairs, devices are used to select the gaps and create a preload, which complicates the design.

A technically achievable result is an increase in efficiency, durability and reliability of transmission.

This is achieved by the fact that in a hydrostatic transmission a screw-nut containing a screw, covered by a screw with a threaded nut, the nut has an equidistant helical surface with a lead screw, for example, of a trapezoidal shape, while on the side surfaces of the screw thread, both from the left and and on the right side, pockets are connected in the nut, connected by means of throttle channels, to distribution channels, which, in turn, are connected through the chokes to the supply line, and the pump, located in the oil bath, and A check valve installed in parallel with it is connected to the supply line through a filter with distribution channel chokes, respectively for the right and left sides of the screw thread in the nut, while the drain tank for the working fluid is a container hydraulically connected to the oil bath.

The drawing shows a diagram of a hydrostatic transmission lead screw-nut.

The hydrostatic transmission of the screw-nut contains a screw 7, covered by a screw nut 6, having an equidistant (congruent) screw surface with a screw screw 7, for example, of a trapezoidal shape, while on the side surfaces of the screw thread, both left and on the right side, in the nut 6 there are pockets 13 connected by throttle channels, for example 11 and 12 on the left side (in the drawing on the right side, the throttle channels are shown with a dashed line), with distribution channels, for example 10 with the left Torons (in the figure to the right distribution channel indicated by a dotted line) which in turn are connected through the inductors 4 and 5 with the supply manifold.

The pockets 13 are recesses in the lateral surface of the screw thread of the nut 6, for example, in the form of round or non-circular holes, hydraulically connected to the throttle channels.

The pump 1, located in the oil bath 8, and a parallel check valve 2 connected to the supply line through the filter 3 with chokes 4 and 5 of the distribution channels respectively for the right and left sides of the screw thread in the nut 6. Drain bath for the working fluid (lubricant oil) serves as a container 9, hydraulically connected to the oil bath 8.

Hydrostatic transmission lead screw-nut works as follows.

Transmission lead screw-nut operates in friction with lubricant.

The pump 1, located in the oil bath 8, delivers through the filter 3, to the chokes 4 and 5 of the distribution channels located in the nut 6, lubricant. The drain bath for the working fluid (lubricant, oil) is a container 9, hydraulically connected to the oil bath 8.

In this gear, the wear of screw 7 and nut 6 is practically absent. The transmission is practically gapless, provides increased accuracy, while the transmission efficiency reaches a value of - 0.99. Compared to the “transmission of the friction screw-nut”, the “rolling screw-nut” has a slightly lower stiffness and bearing capacity due to the presence of an oil wedge.

Claims (1)

Hydrostatic transmission of a lead screw-nut containing a lead screw covered by a screw with a threaded nut, characterized in that the nut has an equidistant helical surface with a lead screw, for example a trapezoidal shape, while on the side surfaces of the screw thread both on the left and on the right side the nut has pockets connected by means of throttle channels to distribution channels, which, in turn, are connected via chokes to the supply line, and a pump placed in an oil bath and parallel to flax mounted to it a check valve connected to a feed manifold through a filter choke distribution channels, respectively for the right and left sides of the screw thread in the nut, wherein the bath to drain the working fluid container is fluidly connected with oil-bath.