RU2568518C2 - Tensioning device - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates to machine building, more specifically to gears with endless flexible elements. The tensioning device contains a casing with stop, lock and socket for handle; handle; regulating tie-rod, and through thread insert with side pin. Besides, the tensioning device has lock made either in form of latch, or floating strap.

EFFECT: increased service life.

5 dwg

Description

The invention relates to transmissions by flexible connection and methods for their tension.

The mechanisms and assemblies of tractors and agricultural machines are driven mainly by belt and chain transmissions, tension pulleys are mainly used for normal transmission tension (Flick EP, Mechanical drives of agricultural machines. - M.: Mechanical Engineering. 1984. - 2702 p., 160) consisting of a pulley, a swing arm, a support axis, a tension bar and a locking device.

A tensioning pulley is planted on the axis of the movable end of the lever, the other end of the lever is mounted on a support axis that provides mobility of the lever, with a pulley in the plane of the tensioned gear.

The tension bar at one end is rigidly connected to the lever, and the other end, having an elongated groove, moves relative to the fixing bolt.

The tension of the transmission is carried out as follows: the fixing bolt of the tension bar is loosened, the lever with the pulley rotates relative to the support axis, the belt is tensioned by pressing the pulley, holding the lever with the force applied to it, the fixing bolt of the tension bar is tightened. Further, the deflection of the working branch determines the correctness of the tension.

The closest invention to the technical solution is the tensioning device for driving the air-cooling fan of the D-37E engine (Gelman B.M., Moskvin M.V. Agricultural tractors. - M .: Higher school, 1978. - 280 pages, p. 111. Fig. 88c), containing a tension pulley with a lever, a support axis, a flexible transmission, an adjusting rod and a stopper.

A significant drawback of the known design is that all adjusting, assembly and disassembling operations are performed under load using various tools and devices for various gears.

In addition, such designs exclude the possibility of quick unloading of the transmission on a temporarily idle machine in order to prevent loss of transmission performance from traction.

All this leads to an unjustified increase in the complexity of technical services and repairs, reducing the resource of belt drives.

The technical solution to the problem is to facilitate and accelerate the process of adjusting and adjusting belt drives, increasing their resource, reducing the complexity of repair and maintenance operations, providing an instant change in gear tension without the use of tools.

This problem found a solution in the device proposed in patent No. RU 2315213 and which is a close prototype.

The device comprises a L-shaped housing, on one side of which there is a supporting axis and a handle stop.

A rocker with a handle is inserted into the supporting axis with one of its ends.

At the opposite end of the beam there is a hinge into which an adjusting rod is inserted with a bent end.

At the opposite end, the thrust is connected to the lever swinging on the axis by means of a thread, on which the tension pulley is fixed.

The idler pulley produces gear tension.

The other side of the L-shaped housing is an emphasis for the hinge and on it is also an emphasis that prevents separation of the bent end of the rod with the hinge.

Additional locking of the rocker arm in the locked position is ensured by a movable horizontal stopper.

The device provides a significant acceleration of the process of adjusting the transmission tension by flexible connection.

The main disadvantage of this device is that a threaded rod having a reference point in the form of a bent end inserted into the hinge has an adjustment interval on only one side of the housing.

In short gears, this drawback is not significant, but in long gears, the stroke of the tension roller is significant and often structurally impossible to use the tensioner on a particular machine.

It is necessary either to change the installation point of the housing on the machine as the transmission stretches, or to have 2-3 different thrust lengths, or use special extension cords.

Another disadvantage of this device is a horizontal stopper.

On agricultural machines with high vibration load it is necessary either to install a spring, or take additional measures to ensure its reliable fixation.

This complicates and increases the design of the tensioner.

The technical solution to the problem is to create a universal tensioning device with an almost unlimited traction relative to the housing, ensuring reliable fixation of the handle by a latch acting under gravity.

This problem is solved as follows: tensioner FIG. 1-3 has a L-shaped housing 1. On one wall of the housing 1 there is a socket 2. An axis 3 of the handle 4 is inserted into the socket 2. The axis 3 in the socket 2 is fixed with a cotter pin 5.

A U-shaped profile 6 of a strip is fixed on the same wall below socket 2 from the strip, through holes of which are coaxially drilled in the ribs. The lock 7 enters these holes.

The latch 7 is bent from a wire in the form of a rectangular bracket with different shoulder lengths.

The shortened shoulder, which is closest to the wall of the body, is fixing, and elongated, in the lower part outside the U-shaped profile, bent 90 degrees, is a drive.

Moreover, the bent end is located from the outer wall of the U-shaped profile 6 at such a distance that when extending upward to contact with the lower edge of the U-shaped profile, the fixing shoulder with its lower end reaches the upper edge of the U-shaped profile, but does not come out of engagement with it .

On the handle 4 perpendicular to its longitudinal axis, a hook 8 is welded at one end.

The other end of the hook 8 extends beyond the walls of the housing 2 and enters the intercostal space of the U-shaped profile 6.

The length of the hook 2 is selected such that it completely overlaps the movable, fixing perpendicular to its axis, retainer arm 7, but does not intersect with the drive arm.

A washer 9 is welded on one side to the handle 4 between its axis 3 and the axis of the hook 8.

On the other hand, in the locked state, the washer 9 abuts against another wall of the U-shaped body 1 parallel to the vertical axis of the handle 4.

The distance from the center of the washer 9 to the axis of the handle 3 is the working arm of the tensioner or conditional rocker.

In this state, the latch 7 with its locking shoulder overlaps with a certain clearance the hook 8 in the intercostal space of the U-shaped profile.

Thus, the mobility of the handle on one side is limited by the wall of the housing, and on the other, by the latch 7.

A pin 10 of a threaded sleeve 11 is inserted into the washer socket 9, into which an adjusting threaded rod 12 is screwed.

An emphasis 13 is welded on the wall of the housing, which prevents the pin 10 of the threaded sleeve 11 from being disconnected from the washer socket 9.

The threaded rod 12 at the end may have a bar 14 with an opening for attachment to the tension roller or bracket 15 of FIG. four.

Thus, the threaded rod 12 in the process of adjusting the tension, rotating in the thread of the sleeve 11, moves relative to the axis of the pin 10 along the housing in a plane parallel to the plane of rotation of the handle 4, at an unlimited distance from the housing in both directions.

For the compact design of the tensioner with a shortened thread “1” of the rod 12, the threaded sleeve 11 may have an internal threaded portion of the thread “h”, offset relative to the axis of the pin 10 (eccentricity “Z”).

This will increase the useful stroke of the thrust with a shortened thread.

In this case, the total traction stroke will be 1 + 2z.

The tensioner works as follows.

At the beginning of work in a new gear, the threaded sleeve 11 is connected by a threaded end located on top with the threaded rod 12.

Raise the latch 7 and release the area for the passage of the hook 8.

Turn the handle up until it is possible to freely insert the pin 10 into the socket of the sleeve 9.

Again, the latch 7 is raised, the handle 4 is turned all the way with the washer 9 into the wall of the housing 1 and the latch 7 is lowered. In this case, the thrust should be fixed automatically due to the pulling force in the thrust and the locking arm “c”.

The position of the tensioner on a particular machine should be such that the axis of the rod 12 is always in the area between the axis of the handle 3 on one side and the wall of the housing on the other.

After the handle is fixed, the device checks the tension in the gear.

As the transmission is pulled, the length of the rod 12 is shortened by screwing the sleeve 11 by hand in the open state.

When the threaded sleeve 11 is abutted against the end of the thread on the rod 12, the sleeve 11 is unscrewed from the rod, turned 180 degrees and again connected to the threaded rod, and so on again to the end of the thread.

On gears with a small stroke of the idler, the threaded sleeve 11 may be shortened and not have an eccentricity “z”.

For such a sleeve, pin 10 is located laterally in the middle of the sleeve.

For ease of use, the tensioner versions can be left or right.

In the front view of FIG. 2, the right tensioner is shown — this is when the axis of the handle 3 enters the socket 2 of the housing 1 on the right, and the pin 10 of the threaded sleeve 10 is inserted into the washer 9 on the left.

On the left, on the contrary, the axis of the handle 3 enters the socket 2 of the housing 1 on the left, and the pin 10 of the threaded sleeve 11 is inserted into the washer on the right.

Tensioners can be normal and inverted.

In a normal tensioner, the working movement of the handle, at which the gear is tensioned, is made from top to bottom, and the gear is pulled from top to bottom.

Inverted - from the bottom up, and accordingly, the working stroke is turned upside down by 180 degrees of the retainer 7, while the transmission tension is carried out from the bottom up.

The latch 7 may have a different design.

For this, the axis 16 is mounted on the outer wall of the housing of FIG. 5.

On the axis 16, on one side, the swinging bar 17 is put on, on the other side of the bar there is an oblong cutout, into which the hook 8 of the handle 4 can enter and be fixed in it.

The permissible stroke of the bar is limited by the stoppers 18 located on the same side of the wall, respectively, for the normal and inverted position of the tensioner housing.

When installing the tensioner in a horizontal position, the strap 17 can be pressed against one of the stoppers 18 forcibly, for this, springs are installed either by twisting 19 on the axis 16, or by stretching 20.

For ease of engagement, the bar on the front may have a bevel.

Thus, the proposed design of the tensioning device allows you to significantly expand the adjustment interval, minimize the mounting dimensions of the tensioner and ensure reliable fixation of the handle.

Claims (1)

A tension device comprising a L-shaped housing with a socket for the axis of the handle and a latch located on one wall of the housing, and on the other wall an emphasis, a handle and an adjusting rod, characterized in that the adjusting rod having at one end connecting elements in the form of a bar or staples with holes, the other threaded end passes inside the threaded sleeve, the side pin of which enters the hole of the washer rigidly connected to the handle, while the separation of the sleeve pin with the washer in the closed state is prevented from ohm, and the handle itself in this position is fixed either by means of a hook located perpendicular to the longitudinal axis of the handle and rigidly connected on one side with the handle, and on the other hand, the hook enters the intercostal space of the U-shaped profile located outside the side wall of the housing, while The U-shaped profile has two pairs of through holes, which include a clamp in the form of a bracket, the shoulder closest to the body of which is fixing, and a distant, elongated, having a bent end in the lower part outside the U-shaped of the profile of the housing — drive, or on the side wall of the housing containing the socket for the handle, there are stoppers and an axis on the outside, a swinging bar is put on one side of the axis, the rotation angle of which is limited by the stoppers, an elongated recess is cut at the other end of the strip, in which in the closed state, the handle hook is fixed, while the side of the bar external to the oblong recess has a bevel, and the bar itself is pressed by a spring to one of the stoppers.

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