RU96203U1 - HYDROMECHANICAL DEVICE FOR RETURNING RETURNING AND SURVIVAL MOTION TO ROTARY WITH TRANSMITTED CHANGE OF THE TRANSMISSION NUMBER - Google Patents

Abstract

 1. A hydromechanical device for converting a reciprocating motion into a rotary one with stepless gear ratio change, characterized in that it contains a piston pump, the cavity of which is connected by hydraulic lines to hydraulic cylinders, the rods of which are connected to a mechanical transmission, while the piston pump rod is connected to a control mechanism. ! 2. The hydromechanical device according to claim 1, characterized in that the mechanical transmission is made in the form of a mechanical connection "gear rack-gear", or "cable-pulley", or "chain-sprocket", while the gear, or pulley, or sprocket placed on the driven shaft. ! 3. The hydromechanical device according to claim 1, characterized in that the length of the hydraulic cylinder rod is selected to be a greater length of the working circumference of the part located on the driven shaft. ! 4. The hydromechanical device according to claim 1, characterized in that the piston pump is made with a fixed cylinder or with two fixed cylinders. ! 5. The hydromechanical device according to claim 1, characterized in that the hydraulic pump is made with a movable cylinder of constant cross section. ! 6. The hydromechanical device according to claim 4, characterized in that the control mechanism is made in the form of two levers, one end of which is pivotally mounted on the piston and cylinder, respectively, and the other ends are pivotally connected to each other and mounted on a carriage located on the guide and configured to reciprocate on it. ! 7. The hydromechanical device according to claim 5, characterized in that the carriage is made with rollers. ! 8. The hydromechanical device according to claim 1, characterized in that it contains additional

Description

The utility model relates to engine building, namely to hydromechanical transmissions with stepless gear ratio change, devices for converting reciprocating motion into rotational one with stepless gear ratio change.

The proposed device can be used as a transmission of vehicles, in particular, driven by muscular power, in power drives and actuator actuators.

Throughout the time since the drive mechanisms appeared, attempts were made to find solutions aimed at reducing the costs of forces, energy and losses during the operation of such mechanisms (as well as the most rational ways to change the gear ratio).

The following patented solutions are known in the art.

From the description of USSR author's certificate No. 808746 (published on 02.28.1981), a hydrostatic transmission is known that contains drive and driven shafts, two adjustable axial-piston machines, each of which contains an inclined washer, the axis of which is perpendicular to the axis of the drive shaft, the cylinder block and installed between they distributor and two pairs of gears connecting the drive and driven shafts, and the gears of the driven shaft are rigidly connected with it. In this case, the cylinder blocks are fixedly mounted on the drive shaft, each of the inclined washers is connected to the corresponding gear of the drive shaft, the distributor is split, and each gear is connected to its corresponding part, and the pairs of gears have different gear ratios.

In addition, a stepless mechanical transmission is known that contains input and output shafts connected to each other by a planetary gear set, two hydraulically connected volumetric hydraulic machines, each of which is connected to the corresponding link of the planetary gear set, while one of them is reversible and adjustable, a feed pump connected to hydraulic lines of hydraulic machines and kinematically connected to the input shaft of the transmission, two controlled gear clutches interlocked with each other. In this case, the other hydraulic machine is made reversible and adjustable and connected to the crown gear, and the first hydraulic machine is connected to the sun gear, the input and output shafts are installed with the possibility of interconnecting one of the controlled gear clutches. The planetary gear carrier was kinematically connected to the input shaft, and one of the links of this series was kinematically connected to the output shaft via the inclusion clutches (AS USSR No. 1194715, published on 02/07/1987).

Also, from the description of the patent of the Russian Federation No. 2133895 (published July 27, 1999), a continuously variable transmission with the ability to control the torque of the strip type is known as groove wheels, comprising a control unit controlled by a driver or other operator (by means of a control element) that changes the gear ratio of a component containing at least one strip in drive contact with two pulley assemblies having parallel but spaced apart from one another axis of rotation and lying essentially in a common radial the th plane, in which each pulley assembly has a shaft and two grooved wheels mounted on it with the possibility of changing the distance between the axes of the grooved wheels, a torque-sensitive connection between at least one pulley assembly and its shaft and means for generating axial force between them, which is a function of the magnitude and direction of the torque transmitted by the pulley assembly, and the load means acting on the pulley assemblies to exert a loading force on the grooved wheels, wherein The torque coupling on one of the shafts contains a ball screw coupling between it and the groove wheel.

The currently known hydraulic transmission designs are most suitable for transmitting high moments at low speeds of rotation of the driven shafts.

The disadvantages of the known devices used to continuously change the gear ratio in vehicles with internal combustion engines are the mismatch of the angular and linear speeds (slippage), which entails restrictions on the magnitude of the transmitted moment, power loss and increased wear of moving structural elements.

The closest analogue to the patented solution is a hydromechanical device for converting reciprocating motion into rotary, which contains at least one piston pump, the piston of which is connected to the control mechanism, while the piston pump is in communication with a cyclic hydraulic actuator with the possibility of converting cyclic angular movements of the shaft hydraulic drive into the rotational movement of the driven shaft of a mechanical transmission. (Patent No. 88088, IPC F16H 61/00 (2006.01), published October 27, 2009).

A disadvantage of the known device is its rather low efficiency, complicated material-intensive design, the need to use two pairs of gears in a mechanical transmission, one of which is meshed by a spurious gear.

The technical result achieved by using the patented solution is, firstly, the improvement and simplification of the control mechanism and its interaction with the pump, which will allow you to change the gear ratio from zero (idle) to any positive value, and secondly, the replacement requires precision execution of a rotary cyclic hydraulic actuator on two linear hydraulic actuators based on conventional standard-sized hydraulic cylinders, eliminating the use of gear pairs or reducing the number of gear pairs to one, which, in turn, will simplify the design, reduce the likelihood of its failure, get the driven shaft to rotate an angle of more than 360 ° in one cycle of the hydraulic cylinders, simplify and lighten the structure, increase efficiency due to better working conditions hydraulic cylinders and reduce friction losses in the mechanical part of the device, as well as the ability to synchronize the angular movement of the drive and driven shafts and, accordingly, the torque values on the drive and driven shaft in one cycle Started device.

The patented solution can be applied in the construction of vehicles with mechanical engines, including aircraft, as a drive of the working bodies of the instrument, in the construction of bicycles and other types of vehicles driven by muscular power.

In addition, when used, for example, in the construction of a bicycle, in comparison with the device already known from patent No. 88888, the following result is achieved:

- weight reduction due to the exclusion of nodes such as a rotary cyclic hydraulic drive and a mechanical transmission, consisting of five gears with the replacement of simpler nodes.

- layout advantages that allow you to place the main components in the protected crankcases included in the design of the bicycle frame and the drive wheel hub.

The claimed technical result is achieved through the use of a hydromechanical device for converting reciprocating motion into rotational motion with a stepless change in the gear ratio, which contains a piston pump, the cavity of which is connected by hydraulic lines to hydraulic cylinders, the rods of which are connected to a mechanical transmission, while the piston pump rod is connected to a control mechanism .

The technical result achieved by using the patented device is ensured by the use in the design of a double-acting piston pump of a double-acting (volumetric hydraulic machine) variable capacity and variable developed force (while productivity and force are inversely proportional to each other). This pump is a pump, the cavity of which is divided into two working chambers filled with working fluid. As a design of a piston pump, three options are offered - with a fixed cylinder, with a movable cylinder of a constant, in contrast to the design of a piston pump of the closest analogue, cross-section, or with two fixed cylinders.

The use of instead of a rotary cyclic hydraulic actuator, as in the device disclosed in patent No. 8888, two hydraulic cylinders, the reciprocating movement of the rods of which is converted into rotational using a simplified mechanical transmission.

As the design of a mechanical transmission, three main types of mechanical connections can be used - “gear rack-pinion”, “cable-pulley” or “chain-sprocket”, while the gear or pulley or sprocket is placed on the driven shaft.

In this case, unlike patent No. 8,088, all the proposed options allow the possibility of obtaining an overdrive without an additional mechanical transmission step, which is made possible by the use of longer rods than the working circumference of the part (gear, pulley, sprocket) located on the driven shaft. When the displacement of the hydraulic cylinder rod is greater than the circumference, the rotation of the driven shaft by more than 360 ° will correspond to one working stroke of the hydraulic cylinder rod, which makes it possible to create a hydromechanical transmission without the use of gear pairs, which was impossible when using the device according to the patent analogue.

When considering the mechanical connection "cable-pulley" is also proposed the option of using eccentric circular and non-circular pulleys to synchronize the movements of the drive and driven shafts (to achieve uniform rotational movement of the shafts) and torques on the shafts.

In order to multiply the gear ratio, the device may contain an additional stage of a mechanical transmission made in the form of a gear pair.

In particular, the control mechanism can be made in the form of two eccentric discs located on the drive shaft of the control mechanism. When using such a design of the control mechanism based on a change in the eccentricity (crank arm) of the eccentric on the input shaft that drives the piston pump, a change in the stroke and, accordingly, the force is achieved.

In addition, the control mechanism can be made in the form of two levers, one of the ends of which is pivotally mounted on the piston and cylinder, respectively, and the other ends are pivotally connected to each other and mounted on a carriage located on the guide and made with the possibility of return translational motion on it. When using a control mechanism of a similar design in combination with a piston pump with a piston of constant cross section, it is possible to regulate the performance of one pump cycle from zero to the total internal volume of the pump cylinder.

In particular, the carriage of the control mechanism can be made with rollers.

Next, the solution is illustrated by reference to the figures.

The figure 1 shows a General view of the device;

Figure 2 - options for mechanical connection of the cable-pulley with the placement of a circular pulley with an eccentricity and an elliptical pulley;

Figure 3 - options for mechanical connection of the rods of the hydraulic cylinders of a mechanical transmission with a part in communication with the driven shaft by means of an overrunning clutch (pulley, sprocket, gear).

In figure 4 - the device of the control mechanism, made in the form of two eccentric discs placed on the drive shaft and the principle of its operation;

Figure 5 - double-acting pump with a constant cylinder diameter, allowing control of the performance of one cycle by changing the ratio of the constant value of the piston stroke (not requiring a change in the eccentricity in the pump rod drive from the drive shaft) to a variable stroke of the movable cylinder;

Figure 6 is a schematic diagram and the operation of a variable displacement piston pump with a movable cylinder and a control mechanism, which is a pantograph;

In figure 7 - piston pumps of variable capacity with a control eccentric and the scheme of the eccentric;

Figure 8 - design of a hydraulic pump with a movable cylinder using a control mechanism using a second eccentric disk, placed coaxially with the first, leading the pump rod, in a plane parallel to it on the drive shaft;

In figure 9 - the design and principle of operation of the piston pump with two stationary cylinders, each of which is divided by the piston into two isolated volumes.

The device shown in figure 1, contains the following main components: a piston pump 1, the cavity of which is connected by hydraulic lines 2 to hydraulic cylinders 3, the rods 4 of which are connected to a mechanical transmission 5, while the piston pump rod 6 is connected to a control mechanism 8, an additional transmission stage - gear pair 9. The control mechanism 8, in this example, is made in the form of an eccentric mechanism located on the drive shaft 10 of the control mechanism. The eccentric mechanism is an eccentric disk 11, an eccentric ring 12 located on the drive shaft 10. The eccentric mechanism is connected via a connecting rod 13 to the rod 6 of the piston pump 1.

When the drive shaft 10 rotates, the eccentric mechanism converts it into the reciprocating movement of the slider-rod 13 of the piston pump 1, which ensures the pumping of the working fluid into one of the two hydraulic cylinders 3 and the pumping of an equal volume from the second hydraulic cylinder, as a result of which the rods 4 of the hydraulic cylinders make a multidirectional linear traffic.

The mechanical connection (pinion-rack, cable-pulley, chain-sprocket), see figure 3, provides a multidirectional rotational movement of two parts (gears, pulleys, sprockets) connected to the driven shaft via unidirectional overrunning clutches 14. One of the clutches runs at idle, and the second tells the driven shaft rotational motion. When changing the direction of movement of the hydraulic cylinder rods with a change of cycle in the hydraulic pump, the second overrunning clutch begins to transmit rotation, and the first is disconnected.

The variants of mechanical connection of the cable-pulley with the placement of a circular pulley with an eccentricity and an elliptical pulley, shown in figure 2, can be used to compensate for the uneven linear movement of the hydraulic cylinder rod, to achieve uniformity of the rotational movement of the driven shaft and to equalize the torque value on this shaft. The pulley, if necessary, can also be made in the form of another convex geometric figure, and the determination of its shape is associated with the determination of the geometry of the movement of the hydraulic cylinder rod.

The figure 4 shows the device and the principle of operation of the control mechanism 8, which can be used to control the performance of a conventional piston hydraulic pump. The control mechanism 8 in this case is combined with the eccentric drive of the pump and consists of two eccentric disks 15 and 16 located on the drive shaft 10. The figure also shows how, when the two disks are turned, the distance AB changes, which determines the overall eccentricity of the system of two disks , and, accordingly, the magnitude of the stroke of the piston of the hydraulic pump. In this case, the pump performance and the magnitude of the developed effort are proportional to the ratio of the length of the connecting rod (lever) of the pedal assembly to the eccentricity of the system of two disks (crank lever) and are inversely proportional to each other. In Figure 3.2. The eccentric assembly with a conventional double-acting hydraulic pump is shown.

Figure 5 (a, b, c, d, e) shows a double-acting piston pump with a constant diameter of the cylinder, which allows controlling the performance of one cycle by changing the ratio of the constant value of the piston stroke (not requiring changing the eccentricity in the pump rod drive from the drive shaft) to variable stroke of the movable cylinder.

The initial (lower) position of the piston is shown in option "a".

In option “b” the moment of completion of the cycle with a stationary cylinder is shown, which corresponds to the maximum pump capacity.

In option “c”, the moment of completion of the cycle is shown when the cylinder is moved a distance equal to the piston’s movement, which corresponds to zero pump capacity (free running in the device as a whole).

In the variant "d" the moment of completion of the cycle is shown when moving the cylinder by an amount of 50% of the piston movement, which corresponds to 50% of the pump capacity.

This design of the pump requires the use of a control mechanism that provides smooth movement of the piston by a predetermined amount.

Figure 6 (a, b, c, d, e) shows a schematic diagram and operation of a variable displacement piston pump 1 with a movable cylinder 17 and a control mechanism, which is a pantograph, the levers 18 of which are fixed by hinges 19 on the pump rod 6 and the housing pump, as well as pivotally interconnected. While the articulation of the levers with each other is placed on the carriage (not shown), with the ability to move along the guide rail 20 of the control mechanism. The free end of the ruler can move, while the guide can change its position, deviating from parallel with the longitudinal axis of the piston pump, thereby determining the relative position of the pump rod and cylinder during their movement during the work cycle. Control action - the movement of the free end of the line of the control mechanism can be carried out by any variant of a mechanical, hydraulic or electric servomechanism.

Variant “a” shows the relative position of the cylinder and the pump stem at the beginning of the stroke; in variant “b” - their relative position with the complete movement of both parts (the guide mechanism guide is parallel to the axis of the hydraulic pump), in variants “c”, “d” and “d” - the relative position of the parts at different angles of deviation of the ruler from the parallel, with a corresponding increase in pump performance.

In Figures 7 (a, b, c), 8 (a, b, c, d, d, e) and 9 (a, b, c, d) the principles of the device and the scheme of operation of hydraulic pumps with a control mechanism of a different design are shown, with application, for performance control, of the second eccentric disk, placed coaxially with the first, leading the pump rod, in a plane parallel to it on the drive shaft. In this case, the second eccentric either controls the movement of the movable cylinder or the operation of the piston in the second cylinder in the variant of a two-cylinder pump. The eccentrics are coaxial, but placed on the drive shaft with a turn of the axes laid from the center of rotation to the geometric centers of the eccentric discs, at an angle from 0 degrees to 180 degrees, with the possibility of changing this angle. The value of the angle of rotation determines the total productivity of the pump (two cylinders or a movable cylinder paired with a piston) during a single cycle.

In the variant "a" of figure 7, the circular paths of the connecting rod mounting to the rings of the eccentric mechanisms (hinges of connecting the connecting rod to the crank in a conventional crank mechanism) are schematically shown. In this case, the eccentric discs are rotated among themselves at an angle of 60 degrees. The relative position of two eccentric discs, rotated among themselves at an angle of 45 degrees, illustrates the option "c".

As shown in option "a", when the eccentrics rotate clockwise in this position, the sliders (rods) 21 move in one direction — downward. This will continue until one of the connecting rods 22 crosses the longitudinal axis of the piston pump and the projection of the drive shaft (point A on the dashed line). After this moment, a multidirectional linear movement of the sliders (rods) 21 will begin and will continue until the second connecting rod 22 crosses the indicated point, after which the unidirectional movement of the sliders (rods) up again will begin.

Thus, the angle of rotation of the two eccentrics relative to each other determines the duration of the antidirectional linear motion in one cycle (full revolution of the drive shaft and the eccentrics placed on it). When the angle of rotation is 180 degrees, as shown in version “b” of figure 8, linear motion is always in antiphase, when the angle is zero, the motion is synchronized, all intermediate values of the angle of rotation set the corresponding ratio of the time of unidirectional and multidirectional movement. This pattern allows you to design on its basis a mechanism for controlling the performance and effort of a hydraulic piston pump.

Figure 8 (a, b, c, d, e, e) illustrates the operation of the piston pump 1 with a movable cylinder 23 using a control mechanism with a second eccentric. In this design, one pair of eccentric connecting rods drives the rod and piston 24 of the pump, the second pair of eccentric connecting rods 25, pivotally connected to the housing of the movable cylinder 23, tells it linear motion. At the same time, when working in antiphase, the cylinder and the pump rod move towards each other, which ensures maximum performance of the hydraulic pump. When the cylinder body and piston move in the same direction, the performance of the hydraulic pump decreases.

Option "a" shows the average position at which the piston divides the internal volume of the pump cylinder into equal volumes and the relative position of the connecting rods in this case.

Options “c” and “g” show the extreme positions of the piston and cylinder of the pump with an eccentric angle of 180 degrees, and accordingly, the pump with maximum performance.

Options "g" and "d" show intermediate positions with a smaller angle of rotation of the eccentrics and the direction of linear movements of the cylinder and piston rod in these positions when the drive shaft rotates clockwise.

Option "e" shows the node in a side view.

Figure 9 (a, b, c, d) shows the design and the principle of operation of the piston pump, with a similar control mechanism shown in figure 9, but with a modified pump design. A pump with two stationary cylinders 26 is used here, each of which is divided by a piston into two isolated volumes. The "upper" and "lower" volumes of the cylinders are interconnected bypass lines, into which the fittings 27 are cut in to connect the hydraulic lines connecting the pump to the hydraulic cylinders of the driven shaft drive.

Option "a" shows the operation of the pump with unidirectional movement of both pistons. In this case, the working fluid is displaced from the volumes V1 and pumped into the volumes V2. Unlike a pump with a movable cylinder, the maximum performance in this design is achieved with unidirectional synchronous movement, which occurs at a zero value for the angle of rotation of the eccentrics.

Option "b" shows the operation of the pump in the opposite direction of movement of the pistons at an equal speed (the turn of the eccentrics is 180 degrees). In this case, the total values of the volumes do not change, the displacement of fluid into the hydraulic cylinders and pumping it does not occur, the system works with zero productivity - at idle.

Option “c” shows the operation of the pump with multidirectional movement of the pistons at different speeds, while part of the volume of the working fluid is pumped from one cylinder to another, part of the working fluid is forced into the “upper” fitting, and an equal volume is pumped into the pump through the “lower” fitting. The system at the same time (with an eccentric turning angle of less than 180 degrees) works with a capacity less than the maximum.

Claims (9)

1. A hydromechanical device for converting a reciprocating motion into a rotary one with stepless gear ratio change, characterized in that it contains a piston pump, the cavity of which is connected by hydraulic lines to hydraulic cylinders, the rods of which are connected to a mechanical transmission, while the piston pump rod is connected to a control mechanism. 2. The hydromechanical device according to claim 1, characterized in that the mechanical transmission is made in the form of a mechanical connection "gear rack-gear", or "cable-pulley", or "chain-sprocket", while the gear, or pulley, or sprocket placed on the driven shaft. 3. The hydromechanical device according to claim 1, characterized in that the length of the hydraulic cylinder rod is selected to be a greater length of the working circumference of the part located on the driven shaft. 4. The hydromechanical device according to claim 1, characterized in that the piston pump is made with a fixed cylinder or with two fixed cylinders. 5. The hydromechanical device according to claim 1, characterized in that the hydraulic pump is made with a movable cylinder of constant cross section. 6. The hydromechanical device according to claim 4, characterized in that the control mechanism is made in the form of two levers, one end of which is pivotally mounted on the piston and cylinder, respectively, and the other ends are pivotally connected to each other and mounted on a carriage located on the guide and configured to reciprocate on it. 7. The hydromechanical device according to claim 5, characterized in that the carriage is made with rollers. 8. The hydromechanical device according to claim 1, characterized in that it contains an additional mechanical transmission in the form of a gear pair. 9. The hydromechanical device according to claim 1, characterized in that the control mechanism consists of two eccentric discs located on the drive shaft of the control mechanism.