Steerable transaxle

Patent metadata

Field	Value
Publication number	US-10337608-B1
Application number	US-201715462398-A
Country	US
Kind code	B1
Filing date	Mar 17, 2017
Priority date	Dec 20, 2013
Publication date	Jul 2, 2019
Grant date	Jul 2, 2019

Abstract

A drive apparatus includes an internal sump and a center section having a pump running surface for mounting a pump cylinder block and at least one motor running surface for mounting at least one motor cylinder block. A brake mechanism includes set of brake rod guides are formed in and extend from the center section adjacent the pump running surface and the one or more motor running surfaces for supporting one or more brake rods. The brake rods may engage the motor cylinder blocks at oblique angle thereto, to provide a braking force. The brake mechanism may include a brake shaft, and a brake arm attached thereto and operatively engaged to the brake rods.

First claim

I claim:

1. A drive apparatus for a vehicle having a prime mover, the drive apparatus comprising:
a housing forming an internal sump;
a transmission disposed in the internal sump and comprising:
a center section containing hydraulic porting;
a hydraulic pump disposed on the center section; and
a first hydraulic motor engaged to and driving a first motor shaft and a second hydraulic motor engaged to and driving a second motor shaft, wherein both hydraulic motors are disposed on the center section and in hydraulic communication with the hydraulic pump through the hydraulic porting to form a hydraulic circuit; and

a brake mechanism having a brake shaft pivotably supported in the housing, a brake arm attached to the brake shaft, and a first brake rod and a second brake rod each supported by a plurality of brake rod guides formed in the center section.

2. The drive apparatus of claim 1 , wherein:
the first hydraulic motor comprises a first motor cylinder block and the second hydraulic motor comprises a second motor cylinder block;
the first brake rod has a first end and a second end, wherein the second end is adjacent to the and capable of engaging with the first motor cylinder block to providing a first braking force thereto; and
the second brake rod has a first end and a second end, wherein the second end is adjacent to the and capable of engaging with the second motor cylinder block to providing a second braking force thereto.

3. The drive apparatus of claim 1 , wherein the plurality of brake rod guides includes a first set of brake rod guides adjacent the brake shaft and a second set of brake rod guides, each of the second set of brake rod guides located adjacent one of the first hydraulic motor and the second hydraulic motor.

4. The drive apparatus of claim 3 , further comprising a cam on the brake shaft and a force transfer member in contact with the cam and in contact with a first end of each of the brake rods, wherein pivoting of the brake shaft causes a second end of the first brake rod to contact and brake the first hydraulic motor and a second end of the second brake rod to contact and brake the second hydraulic motor.

5. The drive apparatus of claim 4 , wherein the cam is integrally formed on the brake shaft.

6. The drive apparatus of claim 1 , wherein the first and second brake rods contact the first and second hydraulic motors, respectively, at oblique angles.

7. The drive apparatus of claim 1 , wherein the center section has a first motor running surface at a first end of the center section and defining a first plane, a second motor running surface at a second end of the center section and defining a second plane, and a pump running surface on a middle portion of the center section and defining a third plane, wherein the first plane is not parallel to the second plane, and the first plane and the second plane are both perpendicular to the third plane.

8. The drive apparatus of claim 1 , wherein one end of the brake shaft is pivotably supported by the center section.

9. The drive apparatus of claim 1 , wherein the center section further comprises a filter land formed thereon and capable of receiving a filter, wherein the filter is connected to the hydraulic porting and to the internal sump.

10. A drive apparatus, comprising:
a housing forming an internal sump;
a center section disposed in the internal sump and comprising a pump running surface, a motor running surface, and hydraulic porting formed in the center section for connecting the pump running surface and the motor running surface;
a hydraulic pump disposed on the pump running surface and connected to the hydraulic porting in the center section; and
a hydraulic motor disposed on the motor running surface and engaged to and driving a motor shaft;
a first brake rod guide extending from the center section adjacent the pump running surface and a second brake rod guide extending from the center section adjacent the motor running surface; and
a brake mechanism having a brake shaft pivotably supported in the housing, a brake arm attached to the brake shaft and a brake rod operatively engaged to the brake shaft, wherein the brake rod is supported by the first brake rod guide and the second brake rod guide.

11. The drive apparatus of claim 10 , wherein the center section further comprises a support member extending therefrom and having an opening formed therein, wherein one end of the brake shaft is pivotably supported in the opening of the support member.

12. The drive apparatus of claim 11 , further comprising a cam on the brake shaft and a force transfer member in contact with the cam and in contact with a first end of the brake rod, wherein pivoting of the brake shaft causes a second end of the brake rod to contact and brake the hydraulic motor.

13. The drive apparatus of claim 10 , wherein the hydraulic motor comprises a motor cylinder block and the brake rod has a first end and a second end, wherein the second end is adjacent to and capable of engaging with the motor cylinder block to providing a braking force thereto.

14. The drive apparatus of claim 13 , wherein the brake rod contacts the motor cylinder block at an oblique angle to provide the braking force thereto.

15. The drive apparatus of claim 10 , wherein the hydraulic motor is a first hydraulic motor and the motor shaft is a first motor shaft and the brake rod is a first brake rod, the drive apparatus further comprising:
a second motor running surface formed on the center section and connected to the pump running surface through at least a portion of the hydraulic porting;
a second hydraulic motor disposed on the second motor running surface and engaged to and driving a second motor shaft;
a third brake rod guide extending from the center section adjacent the pump running surface and a fourth brake rod guide extending from the center section adjacent the second motor running surface; and
wherein the brake mechanism comprises a second brake rod supported by the third brake rod guide and the fourth brake rod guide, and the second brake rod is operatively engaged to the brake shaft.

16. The drive apparatus of claim 15 , further comprising a cam on the brake shaft and a force transfer member in contact with the cam and in contact with the first brake rod and the second brake rod, wherein pivoting of the brake shaft causes the first brake rod to contact and brake the first hydraulic motor and the second brake rod to contact and brake the second hydraulic motor.

17. The drive apparatus of claim 15 , wherein:
the first hydraulic motor comprises a first motor cylinder block and the second hydraulic motor comprises a second motor cylinder block;
the first brake rod has a first end and a second end, wherein the second end is adjacent to the and capable of engaging with the first motor cylinder block to providing a first braking force thereto; and
the second brake rod has a first end and a second end, wherein the second end is adjacent to the and capable of engaging with the second motor cylinder block to providing a second braking force thereto.

18. The drive apparatus of claim 17 , wherein the first brake rod contacts the first motor cylinder block at a first oblique angle and the second brake rod contacts the second motor cylinder block at a second oblique angle.

19. The drive apparatus of claim 15 , wherein the center section further comprises a support member extending therefrom and having an opening formed therein, wherein one end of the brake shaft is pivotably supported in the opening of the suppo

Assignees

• Hydro Gear Lp

Inventors

• Langenfeld Thomas J

Classifications

• F03C1/0636

  having rotary cylinder block · CPC title

• F15B2211/7058

  Rotary output members · CPC title

• F16H61/4157 Primary

  Control of braking, e.g. preventing pump over-speeding when motor acts as a pump · CPC title

• F15B11/16

  with two or more servomotors · CPC title

• F16H39/02

  with liquid motors at a distance from liquid pumps · CPC title