Drive motor arrangement for a hydrostatic transmission

Patent metadata

Field	Value
Publication number	US-10350995-B2
Application number	US-201715692153-A
Country	US
Kind code	B2
Filing date	Aug 31, 2017
Priority date	Aug 31, 2016
Publication date	Jul 16, 2019
Grant date	Jul 16, 2019

Abstract

A hydrostatic transmission includes a side having an upstream radial piston motor and a downstream radial piston motor. The motors are connected to each other in series via a connecting line. A flow control valve is configured to discharge pressure medium from the connecting line so that the downstream motor is only engaged in the event of a predetermined amount of slippage of the upstream motor. Each motor has at least two groups of working flanks. Each flank is configured to operatively interact with a high pressure, such that each motor has at least two transmission steps.

First claim

What is claimed is:

1. A drive motor arrangement for a hydrostatic transmission, comprising:
a first radial piston motor having a variable or adjustable displacement and including a first plurality of unidirectional working flanks subdivided into a first plurality of sub-groups that are configured to activate individually and jointly, and that each include a respective first inlet and a respective first outlet;
a second radial piston motor having a variable or adjustable displacement and including a second plurality of unidirectional working flanks subdivided into a second plurality of sub-groups that are configured to activate individually and jointly, and that each include a respective second inlet and a respective second outlet, wherein the respective first outlets of the first radial piston motor are connected with the respective second inlets of the second radial piston motor via a connection such that the second radial piston motor is connected in series with the first radial piston motor;
a flow control valve connected to the connection between the respective first outlets of the first radial piston motor and the respective second inlets of the second radial piston motor;
a respective displacement change-over valve for each of the first radial piston motor and the second radial piston motor; and
a spring configured to pretension the respective displacement change-over valve,
wherein at least one sub-group of each of the first radial piston motor and the second radial piston motor is configured to activate and deactivate via the respective displacement change-over valve,
wherein the respective displacement change-over valve is configured to connect an inlet and an outlet of the at least one sub-group to each other in a deactivation position, and
wherein the respective displacement change-over valve is a 5/2-way valve such that, in the deactivation position, the respective displacement change-over valve is configured to connect an inlet and an outlet of the at least one sub-group to a control pressure connection.

2. The drive motor arrangement of claim 1 , wherein the flow control valve is positioned on or is integrated into a housing of the first radial piston motor or the second radial piston motor such that an outlet of the flow control valve is connected to an interior space of the housing.

3. The drive motor arrangement of claim 1 , further comprising:
a common connecting line that is connected to each of the respective first outlets via a respective branch line.

4. The drive motor arrangement of claim 3 , wherein the flow control valve is connected to the common connecting line.

5. The drive motor arrangement of claim 3 , wherein the flow control valve is connected to one of the respective branch lines on an outlet side of the respective first outlets of the first plurality of sub-groups.

6. The drive motor arrangement of claim 1 , wherein:
each of the first radial piston motor and the second radial piston motor further includes a respective motor outlet;
the respective displacement change-over valve is a 4/2-way valve such that, in the deactivation position, the respective displacement change-over valve is configured to connect the inlet and the outlet of the at least one sub-group to the respective motor outlet.

7. The drive motor arrangement of claim 6 , wherein:
each of the first radial piston motor and the second radial piston motor further includes a respective motor inlet; and
the respective displacement change-over valve includes:
a first connection that (i) connects the respective motor inlet to an inlet of a further sub-group in the deactivation position, and (ii) connects the respective motor inlet to the inlet of the at least one sub-group and the inlet of the further sub-group in an activation position of the respective displacement change-over valve; and
a second connection that connects the respective motor outlet to the inlet of the at least one sub-group in the deactivation position, and that is shut off in the activation position.

8. The drive motor arrangement of claim 1 , further comprising
a shut-off valve positioned between the control pressure connection and the respective displacement change-over valve, the shut-off valve switchable into an opening position via the control pressure connection.

9. The drive motor arrangement of claim 8 , wherein:
each of the first radial piston motor and the second radial piston motor further includes a respective motor inlet;
each of the first radial piston motor and the second radial piston motor further includes a respective motor outlet; and
the respective displacement change-over valve includes:
a first connection that is shut off in the deactivation position, and that connects the respective motor inlet to the inlet of the at least one sub-group in an activation position of the respective displacement change-over valve;
a second connection that is shut off in the deactivation position, and that connects the respective motor outlet to the outlet of the at least one sub-group in the activation position; and
a third connection that connects the shut-off valve to the inlet and the outlet of the at least one sub-group in the deactivation position, and that is shut off in the activation position.

Assignees

• Bosch Gmbh Robert

Inventors

• Edward Iain

Classifications

• F16H61/444

  by changing the number of pump or motor units in operation · CPC title

• B60K17/10 Primary

  of fluid gearing · CPC title

• F16H61/4043

  Control of a bypass valve · CPC title

• F16H61/44 Primary

  with more than one pump or motor in operation · CPC title

• F16H61/423

  Motor capacity control by fluid pressure control means · CPC title