阅读说明：本技术 一种方捆机压缩力、草捆规则率控制机构及控制方法 (Square baler compression force and bale regular rate control mechanism and control method ) 是由 赵一荣 娄立民 王世强 赵研科 冯春凌 杨东山 钱丹 王德强 邵利国 魏磊 于 2021-08-24 设计创作，主要内容包括：本发明公开一种方捆机压缩力、草捆规则率控制机构及控制方法,包括由四根固定纵梁围成的框架,在框架的四个侧面分别设置有顶侧加压板、底侧固定板、左侧加压板和右侧加压板,顶侧加压板、底侧固定板、左侧加压板和右侧加压板和四根固定纵梁围成两端贯通加压密度室,所述底侧固定板固定在机架上,顶侧加压板、左侧加压板和右侧加压板同一端均通过转轴转动式安装在机架上,并可在密度调节机构带动下进行转动,其中所述顶侧加压板可在竖直面转动,左侧加压板和右侧加压板可在水平面转动。本方案应用于方捆机上,可以提升方捆机的草捆规则率,从而便于堆垛与运输,以降低运输成本。(The invention discloses a mechanism and a method for controlling compression force and bale regularity of a square baler. This scheme is applied to on the side's baler, can promote the bale regular rate of side's baler to be convenient for stack and transportation, with reduce cost of transportation.)

1. The utility model provides a side's baler compression force, bale regular rate control mechanism which characterized in that: the device comprises a frame which is formed by four fixed longitudinal beams in a surrounding mode, wherein a top side pressure plate, a bottom side fixing plate, a left side pressure plate and a right side pressure plate are arranged on four side faces of the frame respectively, and a pressure density chamber with two through ends is formed by the top side pressure plate, the bottom side fixing plate, the left side pressure plate, the right side pressure plate and the four fixed longitudinal beams in a surrounding mode.

2. The square baler compression force, bale rate control mechanism of claim 1, wherein: the density adjusting mechanisms are symmetrically arranged on two sides of the frame and comprise density adjusting oil cylinders, first control arms and second control arms, the first control arms are in butt joint with the upper ends of the density adjusting oil cylinders, the second control arms are in butt joint with the lower ends of the density adjusting oil cylinders, and the first control arms and the second control arms can rotate around the joints of the density adjusting oil cylinders.

3. A square baler compression force, bale rate control mechanism as claimed in claim 2, wherein: first control arm and second control arm all include short armed I and short armed II, and short armed I and II junctions of short armed are formed with the dog-ear, and wherein I tip of short armed is connected with density adjusting cylinder rotary type, and II tip of short armed can be with the left side pressure plate or the right side pressure plate end face contact who corresponds.

4. A square baler compression force, bale rate control mechanism as claimed in claim 3, wherein: the dog-ear department of second control arm forms fixed rotating head, and this fixed rotating head rotary type is installed in the frame, the dog-ear department of first control arm is connected with top side pressure plate both sides joint rotary type.

5. The square baler compression force, bale rate control mechanism of claim 4, wherein: and one end of the inlet of the compression density chamber is provided with a crank sliding block compression mechanism, and the crank sliding block compression mechanism comprises a piston and a crank rocker mechanism used for driving the piston to reciprocate in the compression density chamber.

6. The square baler compression force, bale rate control mechanism of claim 5, wherein: the crank rocker mechanism comprises three connecting pin shafts, a force sensor is arranged at any point of the three connecting pin shafts and used for detecting the maximum stress value at the point and sending the maximum stress value to the controller so as to judge the relation between the maximum stress value and a threshold value, and therefore the density adjusting oil cylinder is adjusted to act.

7. The square baler compression force, bale rate control mechanism of claim 1, wherein: the density adjusting mechanism further comprises a hydraulic control system, the hydraulic control system comprises density adjusting oil cylinders, an electromagnetic directional valve, an overflow valve and an oil tank, and the electromagnetic directional valve is respectively connected with oil inlets and oil outlets of the two density adjusting oil cylinders; when the left position of the electromagnetic directional valve is electrified, the density adjusting oil cylinder extends; when the right position of the electromagnetic directional valve is electrified, the density adjusting oil cylinder retracts; when the power is not on, the electromagnetic directional valve is in the middle position, the density adjusting oil cylinder maintains pressure, the electromagnetic directional valve is also connected with the overflow valve, and hydraulic oil overflows to the oil tank through the overflow valve.

8. A method for controlling compression force and bale regular rate of a square baler is characterized by comprising the following steps:

compressing the material through a crank slider compression mechanism, wherein the formed bale serves as a compression plug during the current compression and provides compression resistance;

secondly, the density adjusting oil cylinder controls the top side compression plate, the left side compression plate and the right side compression plate to loosen or clamp the bales formed by the front working cycle, so that the compression resistance of the fed material during compression is changed, and the bale density is further changed;

and step three, when the crank sliding block compression mechanism compresses the material, compression resistance is generated to act on the piston, and whether the maximum compression resistance exceeds a threshold value or not can be judged by measuring the maximum stress value on the pin shaft at any point of the crank rocker mechanism and performing corresponding control.

9. The method as claimed in claim 8, wherein the method comprises the steps of: in the third step, the force sensor arranged on the pin shaft at any point of the crank rocker mechanism reads the current maximum compression resistance in real time, the current maximum compression resistance is compared with the threshold value by calculating the difference, the controller controls the density adjusting oil cylinder to stretch and contract according to the difference and the threshold value, the clamping force of the material in the compression density chamber is adjusted, and therefore the compression resistance is adjusted.

10. The method of claim 9 wherein the method of controlling the compression force and bale rate of a square baler comprises: the method also comprises the following four steps: the user can manually input the threshold value of the compression resistance through the control terminal, the control program automatically takes the threshold value input by the user as a target, the currently detected compression resistance and the threshold value deviation as an object, the hydraulic system is controlled to change the clamping degree, and finally the compression resistance is enabled to reach the vicinity of the threshold value, so that the corresponding bale density value is reached.

Technical Field

The invention belongs to the field of agricultural machinery, and particularly relates to a mechanism and a method for controlling compression force and bale regularity of a square baler.

Background

The bale density is one of the important technical and performance indexes of the square baler, and the square baler is provided with a density adjusting device for adjusting the bale density. The existing density adjusting device adopts a side plate connected with a spring or a hydraulic cylinder to clamp formed bales, and provides compression force for the compression of the follow-up bales, so that the compression force and the bale density can be changed by changing the clamping degree of the spring or the hydraulic cylinder to the side plate. The bale regular rate is also an important performance index of the bundling machine, and the regular bales are attractive, convenient to stack and transport and low in transportation cost.

However, the existing product structure, control method and the like have a series of problems, mainly: 1. the clamping degree is determined by the stroke of the spring or the hydraulic cylinder, the compression force of a crop with the same water content and the same stroke is the same, but the maximum compression force can be changed in the same stroke due to uneven distribution of the water content in the swath and other factors, so that the operation of the whole machine has risks (such as impact generated by different maximum compression forces, insufficient static strength caused by the maximum compression force and the like). 2. The existing density adjusting device cannot automatically control the subsequent bale distribution rule according to the formed irregular bales, so that the purpose of controlling the bale rule rate is achieved.

Disclosure of Invention

The invention aims to provide a mechanism for controlling the compression force and the bale regularity of a square baler, which is applied to the square baler and can improve the bale regularity of the square baler, thereby facilitating stacking and transportation and reducing the transportation cost.

One of the objects of the present invention is achieved by the following scheme:

the utility model provides a side's bundle machine compression force, bale regular rate control mechanism, includes the frame that is enclosed by four fixed longerons, is provided with top side increased pressure board, bottom side fixed plate, left side increased pressure board and right side increased pressure board respectively in four sides of frame, and top side increased pressure board, bottom side fixed plate, left side increased pressure board and right side increased pressure board and four fixed longerons enclose into the pressurization density room that both ends link up, the bottom side fixed plate is fixed in the frame, and top side increased pressure board, left side increased pressure board and right side increased pressure board are all installed in the frame through the pivot rotary type with one end to can rotate under density adjustment mechanism drives, wherein top side increased pressure board can rotate at vertical face, and left side increased pressure board and right side increased pressure board can rotate at the horizontal plane.

Preferably, the density adjusting mechanisms are symmetrically arranged on two sides of the frame and comprise density adjusting oil cylinders, first control arms and second control arms, the first control arms are in butt joint with the upper ends of the density adjusting oil cylinders, the second control arms are in butt joint with the lower ends of the density adjusting oil cylinders, and the first control arms and the second control arms can rotate at the joints of the density adjusting oil cylinders.

Preferably, the first control arm and the second control arm both comprise a short arm I and a short arm II, a break angle is formed at the joint of the short arm I and the short arm II, the end part of the short arm I is rotatably connected with the density adjusting oil cylinder, and the end part of the short arm II can be in end surface contact with the corresponding left pressure plate or right pressure plate.

Preferably, the bent angle of the second control arm forms a fixed rotating head, the fixed rotating head is rotatably mounted on the frame, and the bent angle of the first control arm is rotatably connected with the joints on two sides of the top side pressurizing plate.

Preferably, one end of the inlet of the compression density chamber is provided with a crank block compression mechanism, and the crank block compression mechanism comprises a piston and a crank and rocker mechanism for driving the piston to reciprocate in the compression density chamber.

As a preferred scheme, the crank rocker mechanism comprises three connecting pin shafts, a force sensor is arranged at any point of the three connecting pin shafts and used for detecting the maximum stress value at the point and sending the maximum stress value to the controller so as to judge the relation between the maximum stress value and a threshold value, and therefore the density adjusting oil cylinder is adjusted to act.

As a preferred scheme, the density adjusting mechanism further comprises a hydraulic control system, the hydraulic control system comprises density adjusting oil cylinders, an electromagnetic directional valve, an overflow valve and an oil tank, and the electromagnetic directional valve is respectively connected with oil inlets and oil outlets of the two density adjusting oil cylinders; when the left position of the electromagnetic directional valve is electrified, the density adjusting oil cylinder extends out; when the right position of the electromagnetic directional valve is electrified, the density adjusting oil cylinder retracts; when the power is not on, the electromagnetic directional valve is in the middle position, the density adjusting oil cylinder maintains pressure, the electromagnetic directional valve is also connected with the overflow valve, and hydraulic oil overflows to the oil tank through the overflow valve.

The second purpose of the invention is realized by adopting the following scheme: a method for controlling compression force and bale regular rate of a square baler comprises the following specific steps:

compressing the material through a crank slider compression mechanism, wherein the formed bale serves as a compression plug during the current compression and provides compression resistance;

secondly, the density adjusting oil cylinder controls the top side compression plate, the left side compression plate and the right side compression plate to loosen or clamp the bales formed by the front working cycle, so that the compression resistance of the fed material during compression is changed, and the bale density is further changed;

and step three, when the crank sliding block compression mechanism compresses the material, compression resistance is generated to act on the piston, and whether the maximum compression resistance exceeds a threshold value or not can be judged by measuring the maximum stress value on the pin shaft at any point of the crank rocker mechanism and performing corresponding control.

As a preferred scheme, in the third step, the force sensor arranged on the pin shaft at any point of the I/J/K reads the current maximum compression resistance in real time, the difference is compared with the threshold value, the controller controls the density adjusting oil cylinder to adjust the clamping force of the material in the pressurized density chamber according to the difference and the threshold value, and therefore adjustment of the compression resistance is achieved.

Preferably, the method further comprises the following steps: the user can manually input the threshold value of the compression resistance through the control terminal, the control program automatically takes the threshold value input by the user as a target, the currently detected compression resistance and the threshold value deviation as an object, the hydraulic system is controlled to change the clamping degree, and finally the compression resistance is enabled to reach the vicinity of the threshold value, so that the corresponding bale density value is reached.

Advantageous effects

Firstly, compared with the prior art (the pressure of a density oil cylinder is kept constant by a control system), the invention has the following effects: (a) stabilizing the maximum connecting rod compression force; (b) and the regular rate control of the bales is realized. The two points can generate bales with uniform density and regular shape, and the maximum compression resistance is constant, so that the impact can be effectively reduced, the fatigue life is prolonged, and mechanical faults caused by instantaneous overload are prevented.

The top side pressure plate, the left side pressure plate and the right side pressure plate are arranged on the frame in a rotating mode, the bottom side fixing plate is fixed on the frame, the pressure plates on the three sides are adjusted and rotated through the density adjusting mechanism, and then clamping force of materials can be adjusted through the pressure plates on the three sides, so that compression resistance of the piston is improved or reduced, bale density is adjusted according to actual conditions of indoor materials of the pressure density, and bales with uniform density and regular shape are manufactured.

And in the third and the preferred scheme, a hydraulic control system is arranged, the hydraulic control system is an electric control system and is matched with the mechanical structure, the response speed and the control precision can be further improved, and the energy consumption is reduced (the power consumption of the electric hydraulic system is about 2.5kW when in action, and the small-range adjustment power consumption of a mechanical mechanism is very small).

The fourth, this scheme still provides a side's bundle machine compression force, bale regular rate control method, considers before this feeding's material is compressed, and there is the anomalous condition in the material of compression in the density room, and when compression mechanism's piston compression was this feeding material, the material can flow to the less both sides face of resistance preferentially, supplyes the part of original disappearance, along with the going on of material replenishment, is full of whole density room gradually. Namely, the mechanical mechanism controls the flow rule of the material in the density chamber according to the resistance distribution in the y direction and the z direction, and the purpose of actively intervening and controlling the bale rule rate is achieved.

In the preferred scheme, a user can manually input the threshold value of the compression force through the control terminal, and input different threshold values according to needs to obtain different bale densities, so that the density adjusting function is realized.

Drawings

In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the invention, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.

FIG. 1 is a mechanical structural view of a control mechanism of the present invention;

FIG. 2 is a schematic diagram of the hydraulic control system of the present invention;

FIG. 3 is a general control diagram of the control mechanism of the present invention;

FIG. 4 is a flowchart of a control method according to the present invention;

FIG. 5 is a force analysis diagram of a pressurized density chamber according to the present invention.

The labels in the figure are: 1. the device comprises a top side pressure plate, a bottom side fixing plate, a left side pressure plate, a right side pressure plate, a vertical fixing beam, a frame, a rotating shaft, a density adjusting mechanism, a first control arm 81, a second control arm 82, a second control arm 83, a density adjusting oil cylinder 9, a crank sliding block compression mechanism 91, a piston 92, a crank rocker mechanism 10, an electromagnetic reversing valve 11, an overflow valve 12, a pressure density chamber 13, a bale formed by a front working cycle, and a material fed this time 14.

Detailed Description

The invention is described in detail below by way of exemplary embodiments. It should be understood, however, that elements, structures and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

It should be noted that: unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. The use of the terms "a" and "an" or "the" and similar referents in the description and claims of the present invention are not to be construed as limiting in number, but rather as indicating the presence of at least one. The word "comprise" or "comprises", and the like, indicates that the element or item listed before "comprises" or "comprising" covers the element or item listed after "comprising" or "comprises" and its equivalents, but does not exclude other elements or items having the same function.

In the embodiment shown in fig. 1, the mechanism for controlling the compression force and bale regularity of a square baler comprises a frame enclosed by four fixed longitudinal beams 5, wherein the fixed longitudinal beams 5 are right-angle irons and are arranged inwards at right angles to form a rectangular space profile, a top side pressurizing plate 1, a bottom side fixing plate 2, a left side pressurizing plate 3 and a right side pressurizing plate 4 are respectively arranged on four sides of the frame, and a space enclosed by the fixed longitudinal beams 5, the top side pressurizing plate 1, the bottom side fixing plate 2, the left side pressurizing plate 3 and the right side pressurizing plate 4 is a pressurizing density chamber 12. Note that the density adjustment cylinder 83 and the control arm at the right pressing plate 4 are symmetrical to the density adjustment cylinder 83 and the control arm at the left pressing plate 3 with respect to the xOz plane, and therefore are not shown in the figure.

In detail, four side plates and four fixed longitudinal beams 5 enclose a pressurized density chamber 12 with two through ends, wherein the fixed longitudinal beams 5 are provided with four corners. Bottom side fixed plate 2 is fixed in frame 6, and top side increased pressure board 1, left side increased pressure board 3 and right side increased pressure board 4 are all installed on frame 6 through 7 rotary types with the end, and top side increased pressure board 1 can be driven vertical face down and rotate at density adjustment mechanism 8, and left side increased pressure board 3 and right side increased pressure board 4 can be driven the horizontal plane rotation down at density adjustment mechanism 8.

In this embodiment, the density adjusting mechanism 8 is a hydraulic device symmetrically disposed on two outer sides of the pressurized density chamber 12 for adjusting the rotation of the top, left and right pressure plates 1, 3 and 4 around the rotation shaft 7, the first and second control arms 81, 82 are not connected to the left and right pressure plates 3, 4, but when the density chamber is filled with the bale, the force applied to the left pressure plate 3 or the right pressure plate 4 by the bale is substantially along the direction perpendicular to the side plates, the force will make the free ends of the first and second control arms 81, 82 contact with the left and right pressure plates 3, 4, respectively, and the two sides of the top pressure plate 1 are also connected to the first and second control arms 81, 82, which can be adjusted by the hydraulic device.

The density adjusting mechanism 8 has the following specific structure: the upper end of the density adjusting oil cylinder 83 is rotatably connected with one end of the first control arm 81, the lower end of the density adjusting oil cylinder 83 is rotatably connected with one end of the second control arm 82, and the first control arm 81 and the second control arm 82 can rotate around the connection position. Wherein first control arm 81 and second control arm 82 comprise short armed I and short armed II by, and the short armed I is formed with the dog-ear with short armed II junction, and wherein short armed I is connected with density adjusting cylinder 83 rotary type, and short armed II can be with the left side pressure plate 3 or the 4 end face contact on the right side pressure plate that correspond. The second control arm 82 has a bent corner to form a fixed rotary head rotatably mounted on the frame 6, and the first control arm 81 has a bent corner rotatably connected to both sides of the top pressurizing plate 1.

In this embodiment, as shown in fig. 1, the top-side pressing plate 1 rotates around an AA' axis, which is mounted on the frame 6, and a D point thereof is hinged to the first control arm 81. One end C point of the density adjusting oil cylinder 83 is hinged with one end of the first control arm 81, and the other end E point of the density adjusting oil cylinder 83 is hinged with the second control arm 82. The second control arm 82 is fixed to the frame at a fixed rotation point F. The left pressing plate 3 rotates about the BB 'axis (the BB' axis is fixed to the frame). The ends of the first and second control arms 81, 82 are not connected to the left press plate 3, but when the density chamber is full of bales, the bales act on the left press plate 3 substantially in the y-direction, which force will bring the end H/G into contact with the left press plate 3 or the right press plate 4, respectively.

As shown in FIG. 2, the scheme designs an electromechanical and hydraulic automatic control system for controlling the mechanical mechanism of the control mechanism, and the control system comprises a density adjusting oil cylinder 83, an electromagnetic directional valve 10, an overflow valve 11, an oil tank and a omitted hydraulic power source. When the left position of the electromagnetic directional valve 10 is electrified, the density adjusting oil cylinder 83 extends out; when the right position of the electromagnetic directional valve 10 is electrified, the density adjusting oil cylinder 83 retracts; when the power is not supplied, the electromagnetic directional valve 10 is positioned at the middle position, the density adjusting oil cylinder 83 maintains the pressure, and the hydraulic oil overflows to the oil tank through the overflow valve 11.

In the embodiment shown in fig. 3, the crank-block compression mechanism 9 is used for compressing the material and is arranged at the inlet of the compression density chamber 12, the crank-block compression mechanism 9 comprises a piston 91 and a crank-rocker mechanism 92, wherein the crank-rocker mechanism 92 is used for driving the piston 91 to reciprocate in the compression density chamber 12, the crank-block compression mechanism 9 of the baler compresses the material, and the bale formed before the compression acts as a compression plug during the current compression, namely, the bale 13 formed in the previous working cycle provides compression resistance. The density adjusting oil cylinder 83 of the hydraulic device controls the top side pressure plate 1, the left side pressure plate 3 and the right side pressure plate 4 of the mechanical mechanism to loosen or clamp the formed bales, so that the compression resistance of the fed material 14 during compression is changed, and the bale density is further changed. When the crank-rocker mechanism 92 compresses the material, compression resistance is generated to act on the piston 91, and whether the maximum compression resistance exceeds a threshold value or not can be judged by measuring the maximum force (kN) on the pin shaft at any point of I/J/K and corresponding control is performed.

The controller reads the current maximum pressure (kN) in real time according to a force sensor which can be arranged on a pin shaft at any point of I/J/K and compares the current maximum pressure (kN) with a threshold value for calculating difference, if the deviation is smaller than a set value (artificially specified value, such as 5 percent of the threshold value), the controller sends a command to ensure that the electromagnetic directional valve 10 is not electrified, the electromagnetic directional valve 10 is positioned at the middle position for pressure maintaining, the stroke of the density adjusting oil cylinder 83 is fixed, and the position of each pressure plate is also fixed. If the deviation is larger than the set value and is a positive value, the current compression resistance is larger than the threshold value, the controller sends out an instruction to electrify the left position of the electromagnetic directional valve 10, the density adjusting oil cylinder 83 extends, the side plate of the mechanical mechanism clamps the material to be reduced, and the compression resistance is reduced until the compression resistance is reduced to be close to the threshold value. If the deviation is larger than the set value and is a negative value, the current compression resistance is smaller than the threshold value, the controller sends out an instruction to electrify the right position of the electromagnetic directional valve 10, the density adjusting oil cylinder 83 is shortened, the clamping of the side plate of the mechanical mechanism to the material is enlarged, and the compression resistance is improved until the side plate rises to be close to the threshold value.

In this embodiment, the mechanism alone can stabilize the compression resistance over a small range, as follows. As shown in FIG. 5, the bale formed in the pressurized density chamber 12 is subjected to force analysis and the forces are labeled in the figure, and it should be noted that the forces are simplified in concentration and include the gravity G of the bale, the pressure Fn provided by the bottom plate fixing plate 2, and the pressure Fy of the left side pressurizing plate 3 on the bale₁Frictional force Ff₂The pressure Fy of the right side pressure plate 4 to the bale₂Frictional force Ff₃Pressure Fz and friction force Ff of top side pressure plate 1 to bale₁The compression resistance Fx to which the bale is subjected. From the force balance, the following system of equations can be obtained:

Fn=G+Fz

Fy₁=Fy₂=Fy

Fx-2fFy-fFz-md²x/dt²=0

in the formula, m is the bale mass, f is the friction coefficient of the material and the side plate, and x is the displacement of the formed bale along the x direction in the compression process.

According to the measurement, the inertia force md²x/dt²The difference in Fx is only about 5-10% greater than Fx, and can be ignored, thus giving the maximum compressive resistance Fx = (2Fy + Fz) f, which is seen to be related to the pressure of the top 1, left 3 and right 4 pressing plates on the bale. From another perspective, Fy, Fz are related to the amount of deformation of the bale after it has been gripped by the compression plates, with Fy, Fz being greater for greater amounts of gripping deformation.

When the stroke of the density adjustment cylinder 83 is fixed (the hydraulic device is in the neutral position), the density adjustment cylinder 83 is kinematically equivalent to a link. If there is a foreign object (such as a large piece of mud) on the top of the bale held by the pressing density chamber 12, Fz will increase, the top pressing plate 1 will rotate counterclockwise around the y-axis, the z-direction clamping degree of the bale will decrease after the rotation, and then Fz will decrease. Meanwhile, the top side pressure plate 1 rotates to lift the height of a point D, the point D is a rotating fulcrum of the first control arm 81, so that the density adjusting oil cylinder 83 integrally moves upwards, the first control arm 81 rotates anticlockwise around the point D along the axis x, the second control arm 82 rotates clockwise around the point F along the axis x, and the two control arms increase the clamping degree of the left and right pressure plates in the y direction and increase Fy. The left and right pressing plates cooperate to maintain the maximum compression resistance while maintaining the upper formula Fx.

Certainly, the mechanical mechanism is not enough to maintain Fx to be constant in a large range, but the mechanical mechanism is matched with the electro-hydraulic device for use, so that the response speed and the control precision can be further improved, and the energy consumption can be further reduced (the power consumption is about 2.5kW when the electro-hydraulic system acts, and the small-range adjustment power consumption of the mechanical mechanism is small).

In this embodiment, the principle of controlling the bale rule rate is as follows: consider the situation where there are irregularities in the material already being compressed in the pressurized density chamber 12 before the material being fed is compressed, such as a small amount of material in the y-direction and a large amount of material in the z-direction. The left and right pressure plates 3, 4 will move inwards and the top pressure plate 1 will be forced upwards into contact with the bale. Although the left and right pressing plates 3, 4 appear to grip the material with a greater amount of deformation, the actual large amount of deformation obtained is due to the absence of material in the lateral direction, and therefore the actual bale force Fy against the side plates is smaller. Therefore, when the piston 91 of the compression mechanism compresses the material fed this time, the material will preferentially flow to the two side surfaces with smaller resistance to supplement the originally missing part, as the material supplement is carried out, Fy is gradually increased, the material side reduces the supplement to the side surfaces, and the whole pressurizing density chamber 12 is gradually filled. Namely, the mechanical mechanism controls the flow rule of the material in the density chamber according to the resistance distribution in the y direction and the z direction, and the purpose of actively intervening and controlling the bale rule rate is achieved.

In this embodiment, the principle of controlling bale density is as follows: under the condition of the same crops and water content, the bale density is directly related to the resistance of the bales in compression, and the higher the resistance is, the higher the density is, and vice versa. The principle is certainly under the premise that the power can be satisfied and the mechanical part of the bundling machine can bear the reaction force caused by the increased resistance. According to this principle, it is possible to design a density adjustment system which, by means of the mechanical mechanism controlled by the hydraulic means described above, clamps the bale in the pressurized density chamber 12 at the level of the force which has been applied to the bale in the previous working cycle, changing the resistance which the bale is subjected to during the open compression of the bale in the following cycle, and thus adjusting the density, as shown in fig. 3.

As shown in fig. 4, a user can manually input a threshold value of the compression force through the control terminal, the control program automatically controls the hydraulic system to change the clamping degree by taking the currently detected compression force and the threshold compression force as targets according to the threshold value input by the user, and finally the threshold compression force is obtained, so that the corresponding bale density value is obtained. Therefore, the user can input different threshold values according to needs to obtain different bale densities, and the density adjusting function is achieved.

The scheme also provides a method for controlling the compression force and the bale regular rate of the square baler, which comprises the following specific steps: firstly, compressing the material through a crank block compression mechanism 9, wherein the formed bale serves as a compression plug during the current compression to provide compression resistance; secondly, the density adjusting oil cylinder 83 controls the top side pressure plate 1, the left side pressure plate 2 and the right side pressure plate 4 to loosen or clamp the bales 13 formed by the front working cycle, so that the compression resistance of the fed materials 14 during compression is changed, and the bale density is further changed; and step three, when the crank block compression mechanism 9 compresses the material, the compression resistance generated along with the compression resistance acts on the piston 91, and whether the maximum compression resistance exceeds a threshold value or not can be judged and corresponding control can be performed by measuring the maximum stress value on the pin shaft at any point of I/J/K. And comparing the difference value with a threshold value, and controlling the density adjusting oil cylinder by the controller to adjust the clamping force of the material in the pressurized density chamber 12, thereby realizing the adjustment of the compression resistance. And step four, a user can manually input a threshold value of the compression force through the control terminal, the control program automatically takes the threshold value input by the user as a target, the currently detected compression force and the threshold compression force are taken as objects, the hydraulic system is controlled to change the clamping degree, the threshold compression force is finally obtained, and then the corresponding bale density value is obtained.

Specifically, in the third step, the controller reads the current maximum pressure in real time according to the force sensor which can be arranged on the pin shaft at any point of the I/J/K, compares the current maximum pressure with the threshold value, compares the difference value with the set value, and if the deviation is smaller than the set value, the controller sends out an instruction to power off the electromagnetic directional valve 10, maintains the pressure when the electromagnetic directional valve 10 is positioned at the middle position, fixes the stroke of the density adjusting oil cylinder 83, and fixes the positions of the top side pressurizing plate 1, the left side pressurizing plate 3 and the right side pressurizing plate 4; if the deviation is larger than the set value and is a positive value, the controller sends out a command to electrify the left position of the electromagnetic directional valve 10, the density adjusting oil cylinder 83 extends, the clamping force of the top side pressurizing plate 1, the left side pressurizing plate 3 and the right side pressurizing plate 4 on the materials is reduced, and the compression resistance is reduced until the deviation is reduced to be near the threshold value; if the deviation is larger than the set value and is a negative value, the controller sends out an instruction to electrify the right position of the electromagnetic directional valve 0, the stroke of the density adjusting oil cylinder 83 is shortened, the clamping force of the top side pressure plate 1, the left side pressure plate 3 and the right side pressure plate 4 on the material is increased, and the compression resistance is improved until the pressure is increased to be close to the threshold value.

The method achieves the purpose of actively intervening and controlling the regular rate of the bales, when the compressed materials are irregular, when the piston of the compression mechanism compresses the fed materials, the materials flow to the two side faces with smaller resistance preferentially, original missing parts are supplemented, and the materials can be filled in the whole density chamber gradually along with the supplement of the materials. Different threshold values are input according to needs so as to obtain different bale densities, and the density adjusting function of the bales can be realized by manually inputting the threshold value of the compression force through the control terminal.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.