Variables speis pump system for closed hydraulic circuits

Abstract

The invention relates to a feed pump system (10) comprising a hydrostatic feed pump (12) which is adapted to generate a hydraulic volume flow to feed it into a closed circuit of a hydrostatic drive, a planetary gear (20) having a planetary carrier (22) Wherein the sun gear is drivable by a drive shaft and a feed pump motor (30) is adapted to drive the ring gear (23) of the planetary gear.

Description

Technical field

[0001] The invention relates to a variable charging pump system used in a closed hydrostatic circuit. The invention particularly relates to a charging pump system capable of generating a variable hydraulic charging flow to be fed into a closed hydrostatic circuit of a hydrostatic transmission device. Background technique

[0002] In a closed-loop hydrostatic system, the loss of hydraulic fluid occurs due to leaks at movable parts or due to loop flushing, for example, for cooling high-load parts or the hydraulic fluid itself. For example, hydraulic fluid flowing through a closed-loop hydraulic circuit can escape through internal leaks in the pump and / or motor, thereby reducing the system pressure below an acceptable limit. In addition, since the hydraulic circuit is closed, the fluid circulating in the closed loop may overheat under load conditions. In order to compensate for escaping and overheated fluids, closed loop circuits often use fixed displacement pumps,...

Examples

Embodiment Construction

[0024] in figure 1 Here, a first embodiment of the charging pump system 10 of the present invention coupled or connected to the hydrostatic main pump 1 is shown in a schematic manner. The hydrostatic pump 1 is driven by a rotary drive device 2 such as a combustion-type drive engine. In this embodiment, the hydrostatic pump 1 is a variable displacement type, however, it may be a constant or fixed displacement pump type. Hydrostatic pump 1 uses working lines 7 and 8 in Figure 1 to Figure 3 The closed hydrostatic circuit shown transports hydraulic fluid. The drive shaft 3 of the main pump 1 connected to the rotation drive device 2 drives the sun gear 21 of the planetary gear set 20. The planet carrier 22 of the planetary gear set 20 is designed to be used as the rotational input power of the charging pump 12. in Figure 1 to Figure 3 In the illustrated embodiment, the internal gear 13 of the feeding pump 12 is driven by the input shaft 11, and the input shaft 11 is connected ...

Technical field

[0001] The invention relates to a variable charging pump system used in a closed hydrostatic circuit. The invention particularly relates to a charging pump system capable of generating a variable hydraulic charging flow to be fed into a closed hydrostatic circuit of a hydrostatic transmission device. Background technique

[0002] In a closed-loop hydrostatic system, the loss of hydraulic fluid occurs due to leaks at movable parts or due to loop flushing, for example, for cooling high-load parts or the hydraulic fluid itself. For example, hydraulic fluid flowing through a closed-loop hydraulic circuit can escape through internal leaks in the pump and / or motor, thereby reducing the system pressure below an acceptable limit. In addition, since the hydraulic circuit is closed, the fluid circulating in the closed loop may overheat under load conditions. In order to compensate for escaping and overheated fluids, closed loop circuits often use fixed displacement pumps,...

Examples

Embodiment Construction

[0024] in figure 1 Here, a first embodiment of the charging pump system 10 of the present invention coupled or connected to the hydrostatic main pump 1 is shown in a schematic manner. The hydrostatic pump 1 is driven by a rotary drive device 2 such as a combustion-type drive engine. In this embodiment, the hydrostatic pump 1 is a variable displacement type, however, it may be a constant or fixed displacement pump type. Hydrostatic pump 1 uses working lines 7 and 8 in Figure 1 to Figure 3 The closed hydrostatic circuit shown transports hydraulic fluid. The drive shaft 3 of the main pump 1 connected to the rotation drive device 2 drives the sun gear 21 of the planetary gear set 20. The planet carrier 22 of the planetary gear set 20 is designed to be used as the rotational input power of the charging pump 12. in Figure 1 to Figure 3 In the illustrated embodiment, the internal gear 13 of the feeding pump 12 is driven by the input shaft 11, and the input shaft 11 is connected ...

Images