JPH0226774Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a steering device configured to steer wheels using double-acting hydraulic cylinders.

[Conventional technology]

In the above steering device, a single rod cylinder has conventionally been used as the fluid pressure cylinder.

[The problem that the idea aims to solve]

Therefore, the bottom side chamber is supplied with fluid so that the wheel oscillation speed when the vehicle is steered is the same as the wheel oscillation speed when the fluid is supplied to the rod side chamber and the vehicle is steered. A flow rate adjustment mechanism is required to make the supply flow rate per unit time to the side chamber larger than the supply flow rate per unit time to the rod side chamber, which has the disadvantage of complicating the structure.

The purpose of the present invention is to be able to steer the wheels to either the left or right side at approximately the same speed, without requiring a flow rate adjustment mechanism, and to prevent unexpected steering operations, compared to conventional configurations. Furthermore, it is an object of the present invention to enable effective use of dead space.

[Means to solve the problem]

The characteristic configuration of the present invention is that vehicle body main frames are arranged at intervals on the left and right, and a connecting frame is constructed across these vehicle body main frames, and the front side of the connecting frame is installed between the left and right vehicle body main frames in a plan view. A double-rod double-acting hydraulic cylinder for steering and a steering driving and swinging member for transmitting the operation of the steering hydraulic cylinder to the wheels are disposed in the space, and the hydraulic cylinder is ,
It is located approximately within the height and width of the main frame of the vehicle body when viewed from the side, and its functions and effects are as follows.

[Effect]

In other words, by steering the wheels with the double-rod cylinder, the cross-sectional area of the cylinder chamber that supplies fluid to steer the wheels to the left and the cross-sectional area of the cylinder chamber that supplies fluid to steer the wheels to the right in the case of double-rod cylinders Since the cross-sectional areas of the cylinder chambers to which the fluid is supplied are the same, there is no need to provide a flow rate adjustment mechanism in order to make the wheel rocking speeds to either the left or right sides substantially the same.

Moreover, since the fluid pressure cylinder and the steering driving/swinging member are located between the left and right vehicle body main frames in plan view and in front of the connection frame, the left and right vehicle body main frames can be accessed from the outside of the left and right vehicle body main frames. The right and left main frames of the vehicle body can prevent weeds and the like from falling into the interior space, and it is possible to prevent weeds and the like from becoming entangled with the fluid pressure cylinder and the steering drive movement member. Therefore, it is possible to avoid malfunctions of the fluid pressure cylinder and the steering drive and movement member that would occur if weeds or the like become entangled with the fluid pressure cylinder and the steering drive and movement member. Further, it is possible to avoid obstacles located on the lateral outer side of the vehicle main frame from coming into contact with these fluid pressure cylinders, etc., and it is possible to prevent these fluid pressure cylinders, etc. from being accidentally operated.

In addition, it is difficult to install connecting rods between the left and right main frames of the car body that span the inside and outside of the main frame because they need to penetrate the main frame. By arranging the steering cylinder, the space that tends to become relatively dead can be effectively utilized.

[Effect of idea]

Therefore, by adopting a double-acting cylinder, it is possible to improve steering performance, avoid malfunction of the steering cylinder, and make the dead space more effective.
In particular, if the connection fittings for supply and discharge of the steering cylinder are installed on the top surface, there will be no collision with stones thrown off the ground, and the connection fittings, which are weaker than the cylinder body, can be attached to the vehicle body. Effective protection can be achieved by cooperating with the mainframe.

〔Example〕

As shown in Figs. 1 and 2, a transmission case 3 is attached to a pair of left and right main frames 1, 1 via a connecting frame 2 so as to be able to swing up and down about an axis _P1 in the longitudinal direction of the car body. A pair of left and right wheels 4, 4 are respectively attached via a transmission case 5 so as to be swingable around the vertical axis _P2 , and a knuckle arm 6 extending from each of the wheel-side transmission cases 5 is connected via a rod 7. A drag link 8 as an interlockingly connected steering driving and swinging member is swingably attached to the differential case portion 3a of the vehicle side transmission case 3 by a rotary shaft 9, and the tube of the double-rod type double-acting cylinder 10 is , is pivotally connected to an arm 11 extending from the rotating shaft 9, and one piston rod is pivotally connected to the vehicle main frame 1, and the electromagnetic control valve V of the cylinder 10 is controlled by a pair of push buttons. switch 12a,
The steering device of the lawn mowing vehicle is configured so that the cylinder 10 steers the wheels 4 by turning on and off both the switches 12a and 12b.

The double-rod type double-acting hydraulic cylinder 10 and the drag link 8 are connected to the left and right vehicle body main frames 1,
1 in the space in front of the connecting frame 2, and weeds, etc. located outside the left and right vehicle body main frames 1, 1 fall into the space and cause damage to the hydraulic cylinder 10.
The main frames 1, 1 of the vehicle body can prevent weeds from falling down and prevent the fluid pressure cylinder 1 from becoming entangled with the drag link 8.
0 and the malfunction of the drag link 8 can be prevented.

Since the cylinder 10 is installed so as to be located within the height and width of the vehicle body main frame 1 in a side view, it is surrounded by the vehicle body main frames 1 and corresponds to the height and width of the vehicle body main frame 1. The installation of this steering cylinder 10 attempts to make effective use of the fact that the space tends to become a dead space.

The cylinder 10 may be provided with the piston rod connected to the wheel side and the tube connected to the vehicle body side.

The steering device according to the present invention can be applied to a steering device configured to automatically steer the wheels in order to align the vehicle body with a reference line or automatically drive according to a program, as well as for combine harvesters, agricultural tractors, transport vehicles, and general vehicles. It can also be applied to various wheels other than lawn mowing vehicles such as passenger cars.

[Brief explanation of the drawing]

The drawings show an embodiment of the steering device according to the present invention, in which FIG. 1 is a plan view of a wheel attachment portion, and FIG. 2 is a sectional view of a drag link attachment portion. DESCRIPTION OF SYMBOLS 1...Vehicle main frame, 2...Connection frame, 4...Wheels, 8...Steering driving and swinging member, 1
0...Fluid pressure cylinder.

Claims (1)

[Scope of utility model registration request] Vehicle main frame 1, 1 spaced apart on the left and right
At the same time, a connecting frame 2 is constructed across these vehicle body main frames 1, 1, and a steering wheel is installed in the space in front of the connecting frame 2 between the left and right vehicle body main frames 1, 1 in plan view. A double-rod double-acting hydraulic cylinder 10 and a steering drive/swing member 8 for transmitting the operation of the steering hydraulic cylinder 10 to the wheels are provided, and the hydraulic cylinder 10 is shown in a side view. The car body main frame 1
A steering device located approximately within the height and width of.