JPS5935563B2 - Traction load detection device for work equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a traction load detection device for a working machine that detects the traction load of a working machine connected to a mobile body.

In order to detect the traction load of the working device, an elastic mechanism is provided that elastically retains the movement of a movable member connected to the working device in the traction direction against the machine body. Many methods are used to detect the traction load based on the resisting displacement.

However, in the past, the movable member could move not only in the traction direction but also in the vertical direction, etc., which caused the downward load due to the weight of the work equipment and the reaction force received from the ground on the work equipment. There was a risk of false detection due to the influence of upward or lateral loads. The present invention
This is a traction load detection device for a work machine that was created keeping in mind the above-mentioned situation, which is a pair of work machine traction load detection devices that are mounted on the moving machine at a distance from each other in the front and back direction and whose plate surfaces face each other. A movable member connected to the working device is penetratingly supported by the pair of plate-shaped parts of the bracket so as to be movable only in the traction direction or substantially in the traction direction, and the plate-shaped member A U-shaped leaf spring is bent into a U-shape, so that one side of the bent opposing piece comes into contact with the plate-like part on the ; side of the bracket to serve as a reaction force receiver,
The plate surface of the bent opposing piece is aligned in a direction orthogonal to the axial direction of the movable member, and the movable member is positioned through this plate surface, and further, the L-shaped leaf spring in the movable member is A pin is provided on the outer shaft portion of the other opposing piece to transmit the movement of the movable member in the axial direction caused by the traction load to the L-shaped leaf spring, and the L-shaped leaf spring caused by the traction load is provided. The present invention is characterized in that a stroke sensor is connected to the movable member and detects the amount of change in elasticity of the movable member as the amount of movement of the movable member.

In other words, since the movable member is supported so as to be movable only in the traction direction or approximately in the traction direction with respect to the aircraft side, it is possible to perform accurate detection with less influence from the above-mentioned loads such as the underground direction and lateral direction. In particular, according to the present invention, since a U-shaped leaf spring is used to elastically hold the movable member, for example, a large coil spring having a large elastic force to resist the traction load is used. Compared to using U
Since the letter-shaped plate spring can be easily formed to have a desired elastic force, it is possible to reduce the cost of the overall structure.

Embodiments of the present invention will be described in detail below with reference to the drawings.

Figure 1 shows a plow 4 as a working device connected to the rear of a plow tractor 1 as a mobile body via a so-called three-point link device consisting of a pair of left and right lower links 2a, 2b and an upper top link 3. A working machine is shown in which a pair of left and right lift arms 6a, 6b driven and swung by a hydraulic cylinder 5 provided at the rear of a tractor 1 and the lower links 2a, 2b are connected via rods 7A, 7b. The plow 4 is configured to be raised and lowered by the expansion and contraction operation of the hydraulic cylinder 5. Next, the plow 40
A device for detecting traction load will be explained.

That is, this detection device has the lower links 2a, 2
A U-shaped frame 8 having a U-shape in plan view is pivotally connected to the end of the lower link 2a, and is used to detect the tensile force acting on the left link 2a in FIG. To,
A headed rod 9 as a movable member is abutted and connected by a head 9a, and this rod 9 is connected to a plate-shaped part 10d bolted to the rear side of the tractor 1, a pair of front and rear plate-shaped parts 10a, 10b, and the pair of plate-like parts 10a, 10b of the support member (bracket) 10, which consists of a plate-like part 10c located on the opposite side of the tractor 1, are attached in the traction direction or approximately in the traction direction (in other words, a lower link in a plan view). It is penetratingly supported so as to be movable only in the longitudinal direction of 2a.

A first pin 1 that is engaged and connected to the rear plate portion 10b.
A second pin 11 whose rear end side (opposing piece) 13b is held in engagement with the rod 9 at 2, and is supported through the rod 9.
A U-shaped plate spring 13 is provided in such a state that the front end side (opposed piece) 13a is engaged and held in contact with the rod 9. movement in the pulling direction is elastically maintained. A swinging arm 15 is pivotally connected to a bracket 14 fixed to a plate-shaped portion 10c of the support member 10 located on the opposite side of the tractor 1.
An L-shaped member 16 screwed onto the end of the rod 9 is pivotally connected near the swinging fulcrum of the arm 15, and
A bolt 17 screwed onto the free end of the arm 15 is connected to an operating rod 19a of a stroke sensor 19 supported on the plate-shaped portion 10c of the support member 10 via a bracket 18.
It is configured so that it can be freely touched. Therefore, this detection device is configured to detect the traction load based on the displacement of the rod 9 that resists the elastic holding force, and uses this detected value as a voltage change due to a change in the amount of protrusion of the rod 19a of the stroke sensor 19. configured to be removed.

The load detection value detected as described above will be used to control the elevation of the plow 4 in order to maintain the tractive load within an appropriate range, and the detection The elevation may be controlled automatically according to the value, or a mechanism for displaying the detected value may be provided to manually control the elevation.

In carrying out the present invention, as described in the embodiment, if both end sides 13a and 13b of the U-shaped spring 13 are abutted and connected using the pins 11 and 12, regardless of the displacement of the spring 13, Since the contact points of the spring 13 with the end sides 13a and 13b do not change greatly, it is convenient for obtaining accurate detection values, and the shape of the pins 11 and 12 is as shown in the &ζ example diagram. In addition to the round shaft shape, a square shaft shape may also be used.

Note that the present invention can also be applied when a rotary tilling device as the working device 4 is connected, and in this case, the movable member 9 is subjected to a pressing force due to the tilling reaction force of the tilling device. Therefore, the configuration is such that the displacement of the movable member 9 due to this pressing force is detected.

[Brief explanation of the drawing]

The drawings show an embodiment of the traction load detection device for a work machine according to the present invention, in which FIG. 1 is a side view of the work machine, FIG. 2 is an expanded vertical side view of the traction load detection device, and FIG. 3 is a traction load detection device. FIG. 2 is a cross-sectional plan view of the device. 1... Mobile body, 4... Working device, 9
......Movable member, 10...Bracket,
10a, 10b...Plate-shaped portion, 11, 12...
...Pin, 13...U-shaped leaf spring, 13a,
13b... Opposing piece.

Claims (1)

[Claims] 1 A traction load detection device for a working machine that detects the traction load of a working machine 4 connected to a mobile body 1, which is provided with plate surfaces spaced apart from each other in the front and back direction of the mobile body 1. A bracket 10 having a pair of plate-like parts 10a and 10b facing each other is attached, and the movable member 9 connected to the working device 4 is attached to the pair of plate-like parts 10a and 10b of the bracket 10 in the pulling direction or approximately. A penetrating support that is movable only in the traction direction, and a U-shaped plate that is bent into a U-shape.
The letter-shaped plate spring 13 is folded into the opposite pieces 13a and 13b.
The plate surfaces of the bent opposing pieces 13a and 13b are perpendicular to the axial direction of the movable member 9 so that one side 13b of the bracket 10 comes into contact with one plate-shaped portion 10b of the bracket 10 and serves as a reaction force receiver. The movable member 9 is positioned along the direction and through this plate surface, and a traction load is applied to the outer shaft portion of the other opposing piece 13a of the L-shaped leaf spring 13 in the movable member 9. A pin 11 is provided to transmit the movement of the movable member 9 in the axial direction caused by the traction load to the L-shaped leaf spring 13. A traction load detection device for a work machine, characterized in that a stroke sensor 19 for detecting the amount of movement is connected to the movable member 9.