RU2176699C2 - Scraper - Google Patents

Abstract

FIELD: mechanical engineering. SUBSTANCE: invention relates to devices designed for mechanical cleaning of coatings. Proposed scraper with drive from tractor has curved lever 5 with wedge-like scraper 6 mounted on frame, bracket 8 to which lever 5 is hinge-connected, coiled spring 11 one end of which rests on lever 5 and the other, on bushing 13 turned into frame. Tie-rod 12 is passed inside spring 11. One end of tie-rod is hinge-connected with lever 5, and on the other end, provided with thread and fitted with clearance into bushing 13, handle 14 is turned. Weight 17 on frame is designed to prevent separation of frame from surface under cleaning. Hinge joint of lever 5 is made in form of eccentric of shaft fitted in lever hole and mounted in bracket 8 and rotated, for instance, by hydraulic drive. EFFECT: improved quality of cleaning. 3 cl, 11 dwg

Description

 The invention relates to trailed devices for the mechanical cleaning of sidewalks and carriageways of hard roads from ice and heavy snow, and works in combination with any self-propelled carriage (tractor).

 It can also be applied in those cases when it is required to provide fast and high-quality cleaning of the surface from rolled sand formations, for example, in the near-border zones of roads.

 As a prototype of the claimed technical solution, a machine was adopted according to A.S. 1418390, a schematic representation of which is shown in FIG. 1 [1, p. 131].

 Based on the claims, the machine contains a chassis 1, in the interbase space of which is mounted rotatably in the vertical plane of the frame, on which, with the help of cylindrical fingers 2, acting as hinges, curved levers 3 with scrapers 4 are fixed. The scrapers are pressed against the surface to be twisted spring 5 and hydraulic cylinder 6, controlled by the main four-line on-off and four-line on-off spool control valve 7. To improve the quality of cleaning and Reliability of work between the scrapers installed discs 8.

 The power transmission links from the hydraulic cylinder are connected to the levers by means of hinges, allowing the levers to swing in a vertical plane.

 The working link here is a lever 3 with a scraper 4. During movement, the scraper, pressed directly to the surface by the action of the springs 5 and the piston of the hydraulic cylinder 6 through the rocker 9, “dives” under the snow-ice formation and cleaves the crust like a wedge, separating it from the surface .

 The disadvantages of this mechanism, the applicant relates the following.

 Firstly, the complexity of the device. It is due to the presence in the design of significant additional movable masses associated with the scraper lever in the form of rods, rocker arms, piston groups, etc.

 When the scraper is working, these masses, possessing inertia, prevent it from swaying in a vertical plane. This factor is especially dangerous when a scraper is stuck on an insurmountable obstacle (ledges of stones, borders, etc.). Additional masses force to reduce the speed of the chassis, which leads to a decrease in performance.

 Secondly, the scraper during operation has one working movement - the movement due to the progressive movement of the machine. It is known in the art that chipping occurs much better if the tool makes a reciprocating (oscillatory) movement.

 Thirdly, due to the tight connection with the lever, the scraper is deprived of the ability to track the irregularities of the surface being cleaned in the transverse direction, which reduces the quality of work.

 Fourthly, in the machine there is a decrease in the operating value of the tractive effort, i.e. hook-and-eye efforts associated with a reduction in its grip weight.

 This decrease is due to the magnitude of the squeezing force from the side of the lever with a scraper resting on the surface being cleaned.

 A drop in traction directly affects the ability to overcome the shear resistance forces, i.e. the ability of the machine to do useful work.

 The purpose of the present invention is to remedy these drawbacks.

This goal is achieved by the fact that:
- the scraper to the surface being cleaned is pressed by one element - a spring equipped with a fixed unit for adjusting its deformation (force), which allows you to have a minimum moving mass and the simplest device;
- in addition to the main scraper, a reciprocating movement is attached;
- the scraper is made self-aligning to track irregularities of the surface being cleaned in the direction transverse to the main movement of the scraper;
- the frame with the scraper device is separated from the self-propelled chassis, equipped with runners and loaded with a passive load, the weight of which is sufficient to compensate for the repulsive force during the operation of the scraper.

The invention is illustrated by drawings, which depict:
in FIG. 1 - machine cleaning snow and ice formations (prototype);
in FIG. 2 - scraper on runners with cargo plates in a side view with one curved lever with a scraper;
in FIG. 3 - a scraper in a plan view, along arrow A in FIG. 2;
in FIG. 4 - a scraper in a front view, along arrow B in FIG. 2;
in FIG. 5 is a cross-sectional view of an adjustable elastic pressure device of a lever according to BB in FIG. 2, increased;
in FIG. 6 is a view of the rear end of the lever with a scraper; the scraper is connected to the lever by a bolt joint acting as a hinge in FIG. 1;
in FIG. 7 is a view of the rear end of the lever with a scraper in the form of an assembly of a steel head and a wear-resistant plate T15K6 fixed on it [2, p. 330];
in FIG. 8 - oscillatory scraper device in a side view with a partial section (in Fig. 2), increased;
in FIG. 9 is a section along G-D along a shaft with an eccentric in FIG. 8;
in FIG. 10 is a section along DD along the shaft with an eccentric in FIG. 9, the front end of the lever 5 is mounted on the eccentric with his ear;
in FIG. 11 is a structural diagram of the lever 5 with an indication of the forces acting on it when a scraper is stuck on an obstacle (metal pin).

The letters in FIG. 11 means:
Q - spring force;
R is the tractor traction force per hook 5;
R ₁ is the reaction force of the obstacle;
F is the resistance force acting on the scraper when it moves along the obstacle;
h, m, n are the shoulders of the action of forces R ₁ , Q, F relative to the hinge 9, respectively.

 Arrow E indicates the direction of the main working movement of the scraper.

In FIG. 1 numbers indicate:
1 - car chassis;
2 - a cylindrical finger, acting as a hinge for mounting a curved lever;
3 - bent lever;
4 - a scraper rigidly fixed to the lever;
5 - coil spring;
6 - a hydraulic cylinder for tightening the hook with a scraper to the surface to be cleaned;
7 - a hydraulic control device for controlling the operation of a hydraulic cylinder;
8 - disk;
9 - rocker.

In FIG. 2 - 11, the same type of parts and assemblies have the same designations. In this case, the numbers indicate:
1 - pipe bent with two parallel branches;
2 - a sheet welded to the branches of the pipe;
3 - jumper, which with the pipe 1 and sheet 2 forms the upper part of the frame;
4 - skid frame, which is the lower part of the frame;
5 - a curved lever;
6 - a scraper rigidly fixed to the lever;
7 - working edge on the scraper 6;
8 - plate, acting as a lever bracket 5;
9 - finger pivotally connecting the lever 5 with the plates 8;
10 - a nut on a finger 9;
11 - spring to tighten the lever with a scraper to the surface being cleaned;
12 - thrust with an eye and a shank with a thread;
13 - a sleeve screwed into the sheet 2 of the frame to change the magnitude of the preload spring 11;
14 - a round handle [3, p. 610], acting as a nut, screwed onto the threaded part of the shank of the rod 12 to limit the rotation of the lever 5 down, as well as turning the lever up when manually scraper 5 from work;
15 - finger pivotally connecting the eye of the rod 12 with the lever 5;
16 - a ring on a frame for a hook on a tractor;
17 - cargo plates to exclude the separation of the frame from the surface being cleaned during operation of the scraping device;
18 - hairpin mounting cargo plates 17;
19 - a nut screwed onto a stud;
20 - self-aligning scraper, tracking irregularities of the surface being cleaned in the direction transverse to the main movement of the scraping unit;
21 - a finger pivotally connecting the scraper 20 with the lever 5;
22 - a nut screwed on a finger 21;
23 - the head of the composite scraper;
24 - a working plate of wear-resistant alloy T15K6 or high-speed steel, soldered to the head 23;
25 - a shaft with an eccentric 26;
26 - an eccentric on a shaft 25;
27 - bushings that act as sliding bearings in the bearings of the shaft 25;
28 - a nut;
29 - washer;
30 - a pulley rigidly mounted on the shaft 25;
31 - V-belt;
32 - nut holding the pulley 30 on the shaft 25;
33 - hydraulic motor;
34 - a pulley on the output shaft of the hydraulic motor;
35 - obstacle (steel pin), which came across a scraper 6 during operation when moving along arrow E.

 The basis of the scraper (Fig. 2) is the frame. Its upper part is made flat and is a combination of a curved pipe 1 and a thick sheet 2 welded to its branches (Fig. 3).

 The ends of the branches are connected by a jumper 3.

 A runner 4 (Fig. 2, Fig. 4), formed by a flexible round bar, is welded to each branch from below. This design of the frame is similar to a sled.

 A scraper device is mounted below on the flat part of the frame. It includes a curved lever 5 (Fig. 2), on the lower rear end of which a scraper is rigidly fixed 6. The latter is made in the form of a wedge, with a pointed working edge 7. made at the top. This edge is used for scraping (cleaving) of ice with ice surface. The front end of the lever 5, the upper one, is placed in the bracket of two plates 8 and connected to them by a finger 9, passed into the holes of the plates and the lever with the formation of a connection that allows the lever to swing in a vertical plane.

 The finger 9 from falling out is fixed with a nut 10 (Fig. 4).

 The plates 8 (Fig. 2) are welded to the sheet 2 from the bottom and are located in front of the scraper 6, and the finger 9 is removed from the surface being cleaned by an amount determined by the calculation (see below).

 To compress the scraper 6 to the surface to be cleaned, the lever 5 is equipped with an elastic clamping device. It is placed behind the finger 9 with the formation of the power shoulder. The device includes a coiled spring 11 (Fig. 2, Fig. 5), inside of which a rod 12, a sleeve 13 and a round handle 14. are missing. The rod 12 consists of a shank and a head. A groove is made in the head with the formation of cheeks, between which the body of the lever 5 is missed. Holes are made in the cheeks and the lever, into which a finger 15 is inserted, which acts as a hinge. The finger is prevented from falling out with its nut.

 The shank of the thrust 12 is threaded. This part is passed with a gap into the hole of the sleeve 13. The gap is necessary to ensure the wiggle rod due to the working wiggle of the lever 5 on the finger 9.

 The sleeve 13 is used to create and control the working pressure of the scraper 5 to the surface to be cleaned by changing the deformation (compression) of the spring 11. For this, the sleeve 13 is made from the outside with a thread that is screwed into the threaded socket in the sheet 2 of the frame.

 Spring 11 is a twisted compression spring. At one end, it abuts against sleeve 13, and at the other, against thrust head 12.

 In front of the frame (Fig. 2, Fig. 3), a ring 16 is welded for hooking the rope of a self-propelled cart (tractor) with a hook.

 At the top of the frame are cargo plates 17 fixed on it with studs 18 with nuts 19.

 The plates and frame must have a weight that excludes the separation of the skids from the surface from the action of forces and moments that arise when the hook and scraper work.

 In FIG. 6 shows the assembly of the lower end of the lever 5 with a removable type self-aligning scraper.

 For this, a groove is made on top of the scraper parallel to its working edge 7 with the formation of two cheeks, between which the shank of the lever 5 is placed. Holes are made in the cheeks and shank, into which the pin 21 is inserted, forming a hinge joint. The finger from falling out is locked with a nut 22.

 This connection makes it possible to swing the scraper on the hook in the transverse direction.

 With the main working movement of the scraper, this possibility under the action of the spring 11 allows you to track surface irregularities in the transverse direction.

 In FIG. 7 shows the same assembly as in FIG. 6, but with a scraper made in the form of an assembly. Here, the scraper consists of a steel head 23 and a working plate 24 made of a wear-resistant material, for example, T15K6 hard alloy or high-speed steel. The plate with the head is connected by soldering using brass. The use of such inserts will reduce the wear of their cutting edges and, thereby, increase the service life when scraping to regrinding.

 In FIG. 8 shows an oscillating scraper device. He has a scraper from the head 23 and the plate 24 oscillates along the line of the main working movement. The vibrational movements of the scraper improve the process of chipping from the surface of the ice or other growth.

 For this, the finger connecting the upper front end of the lever 5 to the bracket 8 is replaced by a shaft 25 with an eccentric 26 (Fig. 8, Fig. 9, Fig. 10). In this case, the shaft supports are the same plates 8 with bushings 27, which serve as sliding bearings.

 On the eccentric 26 of the shaft 25 along the landing fit the front end of the lever 5.

 A washer 29 with a stop function is fixed at one end of the shaft with a nut 28, a pulley 30 with a channel for the V-belt 31 is fixed at the other. The pulley on the shaft is mounted on the key and is secured by the nut 32 through its washer from falling off.

 A hydraulic motor 33 is mounted on the top of the scraper frame, on the output shaft of which is a pulley 34 that transmits rotation to the pulley 30 using a belt 31.

 Work with a scraper begins with its preliminary preparation for work.

Preparation consists in bringing into working condition his working body - a scraping device. It includes:
- creating a squeezing force on the scraper sufficient for scraping;
- providing a margin of rotation of the lever 5 on the finger 9 clockwise after the abutment of the scraper in a cleaned surface.

 The magnitude of the clamping force on the scraper is determined by the magnitude of the deformation (compression) of the spring 11. The greater the deformation, the greater the force on the scraper and vice versa. The deformation of the spring is carried out by rotation of the sleeve 13 on its thread.

 If the right-hand thread is cut on it, then the compression of the spring occurs when the sleeve 13 is turned clockwise, if you look at the sleeve from above.

 In the general case, the magnitude of the clamping force on the scraper is determined empirically by “pulling” the scraper. This effort is related to the shear resistance strength and depends on many factors, such as the type (ice, snow, sand-earth mixture), type (thickness, pebbles, etc.) of the formation to be cleaved, formation temperature, width of the scraper, sharpening angle, etc.

 If scraping is incomplete, it is necessary to increase the amount of deformation of the spring.

 In the case when the scraper scrapes not only ice, but also removes the coating layer (asphalt), it is necessary to reduce the pressure of the spring 11 on the lever 5 with the scraper. This is achieved by rotating the sleeve 13 counterclockwise.

 The margin of rotation of the lever 5 on its finger 9 is necessary so that when the scraper moves on its runners 4, the scraper with its working edge would be able to "get" to the "bottom" of the local recess.

 The value of this value depends on the length of the skis (the size of the scraper) and the "depth" of the bumps. It can be assumed, to a first approximation, that the power reserve of the scraper down should be 5-10 mm.

 In order to set this value, it is necessary to install the scraper with its runners on a flat area with a smooth surface, i.e. without cracks, crevices and protrusions. Then, by rotating the handle 14, “lower” the lever 5 to the position where the scraper abuts against the surface of the site. "Lowering" of the lever comes from the action of the spring 11, which is in a compressed state.

 The "lowering" of the lever is its rotation on the finger 9. As the lever is rotated and the scraper is lowered, the spring is straightened, and the rotation force by the handle 14 decreases. This happens until the scraper reaches the surface of the site. With further rotation, the force on the handle becomes minimal, and rotation is free. From this moment, the handle with further rotation will rise up the shank of the rod 12, forming a gap between the handle and the sleeve. If the longitudinal axis of the rod 12 passes through the working edge 7 of the scraper, then the gap between the sleeve and the handle will be the magnitude of the stroke of the scraper down from its average operating position. At a different location of the thrust 12, appropriate corrections must be made.

 The work of the tuned scraper is to give it movement in the E direction (Fig. 2, Fig. 8), i.e. when the lever 5 with the scraper are located behind the finger 9. The movement is determined by the working force “on the hook” of the walking tractor or other self-propelled cart.

 When moving, the scraper opens up an ice or other growth, its working edge reaches the road surface and, moving further, the scraper, acting as a wedge, “dives” under the growth and cleaves it from below. In this case, the spring 11 plays the role of a stop, preventing the scraper from disengaging from the outgrowth - an ice or other crust.

 Scraping to a "clean" surface is the work of the scraping machine in normal mode.

 Now we should consider the case when an “insurmountable” (indestructible) obstacle in the form of a small protrusion formed, for example, by a steel pipe, a kingpin, etc., comes across a moving scraper.

 In this situation, the scraper will self-disconnect from work and it will “jump over” the obstacle, as it were, and then enter into operation.

 In fact, immediately, as soon as the scraper hits the obstacle, the scraper immediately begins to move up the obstacle. This is because the lever, under the action of the horizontal resistance force from the obstacle, rotates counterclockwise around the finger 9. With its movement, the lever additionally compresses the spring, overcoming its resistance. Along with this, the scraper, moving up the obstacle, creates a friction force, which also prevents its lifting, i.e. turn the lever counterclockwise.

 However, due to the fact that the moments created by the spring force and the friction force around the finger 9 are less than the active moment around the same finger from the gravity created by the tractor, the scraper "creeps" up the obstacle. This happens until the scraper reaches the top of the obstacle. In this case, the lift stops and the scraper begins to slide over the obstacle per se, reaching its edge. With further movement, the scraper "jumps" from an obstacle onto an ice surface and explodes into it. This is due to the rotation of the lever clockwise from the action of the compressed spring.

 The same scheme of operation of the scraping device occurs from the ingress of the scraper into the crack. In this case, its upward movement does not start from “zero”, i.e. from the level of the cleaned surface, and a lower level, the depth of which is not more than the value of the power reserve of the scraper (5-10 mm), as mentioned above.

 The described process of self-shutting off and turning on the scraper in operation occurs quickly, in the movement mode of the scraping unit with the tractor (up to 20-30 km / h or more), without causing tool breakage.

 When the hydraulic motor 33 (Fig. 8) is turned on, its output shaft and the pulley 34 mounted on it receives rotation. This rotation is transmitted to the pulley 30 with the shaft 25 and the eccentric 26 using the V-belt 31. The eccentric rotates the front end of the lever 5 with its rotation This means that this end first, for example, moves forward, then up, then back, then down, then forward, etc.

 The scraper would have to repeat all the indicated movements if there had not been a forceful action of the spring 11 on the hook 5. This action, always directed downward, does not allow the rear end of the hook with the scraper to go up, but the surface being cleaned does not allow it to descend. It follows that the up-down movement is cut off at the scraper, but the forward-backward movement remains. This movement is reciprocating, oscillatory (vibrational).

 The device and operation in this case resemble the device and operation of the crank mechanism. Here, the role of the crank is performed by the eccentric 26 of the shaft 25, the role of the connecting rod is the lever 5, and the slider is the scraper 6. The radius of the crank is the eccentricity of the eccentric.

 The reciprocating motion of the scraper will greatly facilitate the cleavage of ice from the surface during operation of the scraper. Work with a vibrating tool is observed in everyday life. For example, the action of a jackhammer with a chisel when opening a road asphalt pavement, chipping of gates from cast steel parts, work in a coal face, etc.

 If these hammers did not have a reciprocating movement of the tool (chisel), useful work would be impossible.

 In combination with the main movement of the scraper due to the translational movement of the tractor, its oscillatory movement will improve the quality of the surface being cleaned. The presence of oscillatory motion will little change the behavior of the scraper when overcoming obstacles, rather than in its absence, because the magnitude of the amplitude of the fluctuation, according to the applicant, should be small, of the order of 2-3 mm.

 Ensuring self-disconnection of the scraper scraper device from work when the scraper is stuck on the obstacle is possible if the condition determining the position of the line of action of the spring force 11 relative to the hinge 9 is met.

 To find this condition, refer to FIG. eleven.

 It depicts a structural diagram of the lever 5 with the scraper 6 at the moment when the scraper moves along the arrow "E", and the scraper came across an obstacle 35 and "creeps" upwards on it.

Indicated here:
R is the tractor traction force;
R ₁ - reaction force (resistance) barriers;
F is the resistance force (friction) that occurs when the scraper moves along the barrier up;
h, n are the arms of the force R ₁ and force F relative to the hinge 9, respectively.

The equation of moments relative to the hinge 9 looks like this
∑ M ₉ = 0. (1)
Without taking into account the moments of the dead weight forces of the lever, spring, rod, handle and finger relative to the hinge 9 and the moments of inertia of these parts relative to the same hinge, equation (1) takes the form
-Q • m - F • n + R ₁ • h = 0, (2)
where from
Q • m = R ₁ • h - F • n. (3)
For even movement
R ₁ = R. (4)
We accept that
F = R ₁ • f, (5)
where f is the coefficient of friction of the sliding of the scraper over the barrier. Then expression (5) takes the form
Q • m = R • h - R • f • n. (6)
It is easy to see that in order to achieve self-shutdown, equation (6) must have the form of an inequality, i.e.

Из выражения (8) вытекает, что при f ≈ 0

С ростом коэффициента трения f размер плеча m уменьшается.Q • m ≤ R • h - R • f • n. (7)
Then the desired condition is determined as

It follows from expression (8) that for f ≈ 0

As the coefficient of friction f increases, the shoulder size m decreases.

 The value of m will also decrease if we take into account the weight and inertia of the moving masses of the scraper assembly.

 However, this work can be carried out only if there is a specific design of the scraper assembly and when the specified law (speed) of the lever rotation around its hinge is realized.

 In general, this problem is solved by the method of successive approximations. However, this work is not included in the scope of the claimed technical solution.

So, the presented scraper solves the task - cleaning the pavement from the growth. Wherein:
- the scraper to the surface being cleaned is pressed by one element - a spring, which allows you to have the simplest and, therefore, reliable device containing moving parts having minimal inertial masses, which determine the working speed of the scraper;
- the scraper, in addition to the main one, is given a reciprocating (oscillatory) movement, which facilitates the process of cleaving the growth on the coating and improves the quality of cleaning;
- the scraper is made self-aligning, which allows it to track irregularities of the surface being cleaned in the direction transverse to the main movement of the scraping unit; the removability of the scraper allows its quick change when the working edge is dull;
- the frame with the scraper device is separated from the self-propelled chassis and is made on runners in the form of an independent unit, loaded with a passive load in the form of plates; this circumstance does not reduce the grip weight of the tractor and, therefore, does not reduce the working pulling force on the hook, which positively affects the productivity of cleaning the surface;
- the scraper device ensures that the scraper is self-disconnected from operation when it is stuck on an obstacle or gets into a crack and is put into operation immediately after passing obstacles without breakage, and these operations can be carried out most quickly due to the low inertia of the scraper device.

 In conclusion, it should be noted that a single-hook scraper is provided. The real design of the scraper implies the presence of several hooks with scrapers, placed in several rows of several units in each row with overlapping areas of operation of the scrapers of the previous row with the areas of operation of the scrapers of the next. This improves the quality of the surface being cleaned.

 To avoid clogging of the interbase space with ice crumb, the scraping device should be “transparent”, i.e. have high snakes and hooks and resemble a spider.

 Equipping the scraper with a blade knife (scraper) of the grader type [4, p. 465] and a brush shaft like a road sweeper, we obtain an aggregate capable of solving the task of cleaning the surface with the greatest efficiency.

 To ensure the operation of the scraper in the summer, when removing earthen-sand outgrowths from road surfaces, it is advisable to replace the runners with tracks or wheels.

Literature
1. "Discoveries, inventions. Official Gazette of the State Committee for Inventions and Discoveries." SCST USSR, N 31, 1988, Moscow.

 2. "Reference technologist-machine builder", t. 2, 1959, Moscow.

 3. Anuryev V.I. "Reference designer-mechanical engineer", t. 1, 1978, Moscow.

 4. "The Great Soviet Encyclopedia", t.6, 1977, Moscow.

Claims (3)

 1. Scraper for cleaning road surfaces from ice and dense snow, containing a curved lever located on the frame with a scraper at the lower end in the form of a wedge facing the surface to be treated, an arm located in front of the scraper and pivotally connected to the other end of the lever to ensure the lever to swing a plane parallel to the vertical plane of symmetry of the frame, a coil spring for preloading the scraper with the formation of a power shoulder around the hinge, characterized in that it is driven by a tractor and equipped with in order to prevent the frame from tearing off the surface being cleaned, the spring rests on one end of the lever and the other on the sleeve screwed into the frame, a rod is missing inside the spring, one end of which is pivotally connected to the lever and the other end threaded, inserted into the sleeve with the gap, the handle is screwed on, the lever hinge is made in the form of an eccentric shaft located in its hole, mounted in the specified bracket and rotated by a drive, for example, a hydraulic one.  2. The scraper according to claim 1, characterized in that a groove is made in the scraper parallel to the working edge, forming cheeks, between which the lever shank is placed and connected to them with the possibility of rocking by means of a finger.  3. The scraper according to claims 1 and 2, characterized in that the scraper is made of a steel head and a hard alloy plate welded together, for example T15K6, the plate being longer or equal to the width of the head.

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