DK162791B - GEAR MACHINE, ISAER HYDRAULIC GEAR ENGINE - Google Patents

Description

DK 162791B

The invention relates to a cogwheel machine of the kind mentioned in the preamble of claim 1 and, more particularly, to a further development of the cogwheel machine described in the specification for Danish patent application No. 5300/83 with a parking brake 5 or lock.

Low-speed gearboxes and high torque are frequently used to pull the drive wheels on vehicles, so it is desirable that the engine include some type of parking brake. Another 10 widely used use of these engines is to operate auxiliary power units in vehicles e.g. hoists and games, and in applications of this nature it is desirable that the engine be able to sustain a load. It is generally well known to block cog mechanisms by inserting a locking member into the path of one of the gears.

Although the invention may be used in hydraulic gear machines which act as pumps, it is particularly advantageous for use in an apparatus operating as a motor, and will be described in the following in connection with such an engine.

Hydraulic motors with this type of displacement mechanism have been popular for many years for applications requiring low speeds and high torques.

These motors typically consist of a housing having a fluid inlet and a fluid outlet and a gearing machine of the kind in connection with the housing. The gearwheel usually includes an inner toothed ring secured in the housing and an outer toothed planet wheel 30 which is eccentrically disposed in the tooth ring and performs an orbiting and rotating motion thereon.

The teeth of the gear ring and of the planetary wheel engage each other, delimiting expanding and contracting work chambers during relative motion. A distributor valve 35 in the housing is adapted to provide fluid communication between

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2 shows the fluid inlet and the expanding fluid chambers and between the contracting fluid chambers and the fluid outlet.

A power transmission shaft · is rotatably mounted in and extending out of the housing, and a power shaft is at one end in contact with the planet wheel and at its other end with the power transmission shaft for converting the orbiting and rotating motion of the planet wheel into a slow rotating motion by large torque of the power transmission shaft.

It is well known to those skilled in the art that various other arrangements of this type of gearing machine are known than the one described above, in which the gear ring is attached to the housing and the planetary wheel orbits and rotates, and although the invention may advantageously be applied in connection with such other gear arrangements which are described later, the arrangement described above is the most common and is part of a preferred embodiment of the invention.

An attempt to provide a parking brake motor is disclosed in U.S. Patent No. 3,616,882, where a thin, flexible friction member may be pressurized into contact with one side of the gear wheel's planet wheels. However, this arrangement seems to have caused a great deal of 25 large frictional forces and high heat generation with the risk of damaging the side surface of the planet wheel. Furthermore, the parking brake described does not act as a safe mechanical lock, but its effect depends on the presence of a hydraulic pressure.

Another suggestion of a positive-acting brake is the set of discs, some of the discs being attached to the stationary housing, and intermediate discs being wedged on the rotary power transmission shaft. The discs are usually spring-loaded into contact with each other (braking) and a hydraulic pressure is required to disengage the discs. In one embodiment 3

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commercially available, the disk sets are located in the gear unit housing and are arranged to lock the engine power transmission shaft to the motor housing. This solution requires an almost complete redesign of the engine-5 housing and power transmission shaft, which is why in practice it is impossible to offer a parking brake as an optional supplement to an engine. In another construction, a separate parking brake device engages the engine's power transmission shaft and is provided with its own housing and a separate hinge shaft which can be locked by a group of washers engaging each other. This separate parking brake has the advantage that it can be added as a supplement to the engine, since no significant change to the engine is required, but the expenses for the existing parking brake can be as large as or more than the cost of the gear motor itself.

The invention provides a hydraulic gearwheel with an integral parking brake (or 20 lock) which does not involve any alterations or additions to the hydraulic circuit of the engine.

It is also an object of the invention to provide a parking brake with safe operation, ie. providing a positive-acting mechanical lock that prevents rotation of the engine's power transmission shaft.

Further, it is an object of the invention to provide a parking brake which forms an integral part of the engine but can be optionally added to the engine 30 at reasonable cost without requiring substantial engine restructuring.

These and other objects and advantages of the invention are achieved by a gearwheel machine of the kind according to the invention characterized by the features of the characterizing part of claim 1.

A simple embodiment of the gear unit according to 4

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The invention, which is particularly suitable for hydraulic motors of the kind described above, is described in claim 2.

Further embodiments and constructive features of the cogwheel machine of the invention are set forth in the other dependent claims and will be explained below with reference to the accompanying drawings, in which: FIG. 1 shows an axial section through a low speed and high torque gear of the invention, FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1 and showing the locking means according to the invention; 3 shows, on a larger scale, a partial image similar to FIG. 2, but in the form of a plan view of the gear mechanism displacement mechanism; and FIG. 4 is a view of FIG. 2 shows a cross-section in which we see an alternative embodiment of a hydraulic gearwheel according to the invention.

FIG. 1 shows a gear motor for low speeds and high torque with internal engagement and planetary movement of an externally toothed gear in an internally toothed gear ring in which the invention can be applied. The engine is of the type shown and described in greater detail in U.S. Patent Nos. 3,572,983 and 4,343,600 to which reference is made herein.

The FIG. 1 hydraulic motor 1 consists of a number of sections which are assembled together, e.g. by means of a plurality of bolts 11 shown in FIG. 2nd

The motor has a shaft bearing housing 13, a wear plate 15, a planetary housing 17 (displacement mechanism), a valve stator 19 and a valve housing 21.

The planetary wheel housing 17 is well known and is described in detail in the aforementioned patent specifications, which is why it is only briefly mentioned here. The planet wheel housing 17 is a so-called Geroler® mechanism with an internally toothed ring 23 defining a plurality of substantially half-cylindrical rings.

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drill openings, and with a cylindrical body 27 (roller tooth) disposed in each of the openings. An externally toothed sprocket 27, which acts as a planet wheel, is eccentrically mounted in the ring 23 and typically has a plurality of exterior teeth which is one less than the number of roller teeth 25 so that the externally toothed sprocket 27 may circle. and rotate relative to the ring 23. The relative circular and rotary movement between the ring 23 and the externally toothed gear 27 provides a plurality of expanding and contracting work chambers 29.

In FIG. 1, it is further seen that the motor has a power transmission shaft 31 which is rotatably mounted in the shaft bearing housing 13 by means of suitable bearing sets 33 and 35. The shaft 31 has a set of internal straight manifold teeth 37, and in engagement therewith is a set of exterior. bombed mannequins 39 formed on one end of a cardan shaft 41. On the opposite end of the cardan shaft 41 there is another set of exterior, bombed multi-20 notch 43 which engages a set of internal straight mannequins 45 which are formed internally in the outer toothed gear 27 forming planetary wheels. Therefore, since the ring 23 in the illustrated embodiment has seven internal teeth 25 and the outer toothed tooth 25 wheel 27 has six external teeth, six circular motions of the gear 27 will result in a complete rotation of the gear and a complete rotation of the shaft 41 and power transmission shaft 31.

As is well known, the axis of the PTO shaft 41 always forms an angle with the main axis of the motor, ie. the central axis of the internally toothed ring 23 and the power transmission shaft 31. The primary function of the shaft 41 is to transmit torque from the externally toothed gear 27 to the power transmission shaft 31.

This is done by transposing the orbiting and rotating

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moving the gear 27 in a clean rotary motion of the power transmission shaft 31.

Also engaging the internal manifold teeth 45 are a set of external manifold teeth 47 formed around one end of a valve shaft 49, at the opposite end of which is another set of exterior manifold 51 engaging a set of internal members. manifold teeth 53 formed around the inner periphery of a valve rotor 55. Valve rotor 55 is pivotally mounted in valve housing 21. Valve shaft 49 is at many nut teeth in connection with both the externally toothed sprocket 27 and valve rotor 55 to maintain properly timed valve control between them, as is well known in the art.

The valve housing 21 has a fluid inlet 57 which is in communication with an annular chamber 59 surrounding the valve rotor 55. The valve housing 21 also has a fluid outlet 61 disposed between the valve housing 21 and the valve rotor 55. The valve rotor 55 forms a plurality of alternately 20 valve passages. 65, 67, wherein the passages 65 are still in fluid communication with the annular chamber 59, while the passages 67 are in still fluid communication with the chamber 63. In the embodiment shown, there are six passages 65 and six passages 67 corresponding to the six external teeth of the cog 27. Valve stator 19 defines a plurality of valve passages 69, only one of which is shown in FIG. 1, and these passages are still in fluid communication with the nearest working chamber 29. Engines of the type shown in FIG. 1 is commercially available and is well known to those skilled in the art, and with reference to the further details of construction or operation, reference is made to the aforementioned patents.

An engine according to the invention with locking means or brake is described below with reference to FIG.

35 and 2 in connection with FIGS. 1. As best seen in FIG. 1 and 2, the inner toothed ring 23 has a 7

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generally radially projecting cam 71. In this cam 71 is formed a bore 73 extending radially inwardly and ending in one of the chambers 29. The bore includes an inner, smooth bore 75 and an outer, 5 wider, threaded portion 77.

The bore 75 is crossed by an axially oriented U-shaped recess 79 with downward opening (see Fig. 3).

The recess 79 preferably extends throughout the axial length of the tooth ring 23. An elongated, substantially cylindrical locking member 81 is disposed in the recess 79. The locking member 81 is held in the recess 79 because the opening formed where recess 79 intersects the working chamber 29 the circumferential direction, has a width w smaller than the diameter of the locking member 81 (see Fig. 3). As best seen in FIG. 2 and 3, recess 79 is arranged between a pair of adjacent inner roller teeth 25 circumferentially. In FIG. 3, it is further seen that the recess 79 is designed to allow some radial movement of the locking member 81 and the purpose 20 is explained further below.

Adjacent to the radial aperture 73 is an operating mechanism, which as a whole is designated 83. The operating mechanism 83 includes a generally cylindrical support member 85 disposed in the bore 75.

The support member 85 includes an O-ring which is positioned between the support member and the bore 75 to prevent fluid leakage past the support member 85 when the adjacent work chamber 29 contains fluid under pressure. The support member 85 has an end face 87 which is formed as part 30 of a cylinder and engages the cylindrical locking member 81.

The operating mechanism 83 further includes a guide member 89 disposed in the opening 73 near the end of the support member 85. The guide member 89 has an external thread member 91 which is screwed into the threaded portion 77 of the bore 73. The guide member 89 also has a ridge. -

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8 is a light portion 93 capable of receiving a handle not shown, whereby movement of the handle induces rotation of the control member 89 and either movement radially inward or radially outward, depending on the direction in which the handle is moved.

The guide member 89 also has a second external threaded portion 95 capable of receiving a nut (not shown) for holding the handle.

Referring now in particular to FIG. 2 in connection with a description of the locking or braking of the motor according to the invention. When the engine is to operate normally, ie. that the externally toothed sprocket 27 performs its normal circular and rotary motion relative to the ring 23, the locking mechanism is set to idle. This is caused by the handle (not shown) being moved so that it has turned the control member 89 in such a direction that it is moved upwards in FIG. 2, radially away from the gear 27. This movement of the guide member 89 causes the orbital movement of the gear 27 to force the locking member 81 and the support member 85 radially upwardly against the guide member 89. Due to the O-ring surrounding the support member 85, this will then normally remain in this top position, as described above. However, the locking means 81 will be free to move radially in the recess 79, and only move radially upwardly as one of the teeth of the gear 27 moves into the working chamber closest to the locking means 81, causing this chamber to approach the state in which it has. minimal volume (see Fig. 3). The gear 27 then continues its orbital motion, and the volume of the nearest working chamber grows, and the locking means 81 will be free to move radially inward only under the influence of gravity and back to that of FIG. 2.

When you want to activate the lock mechanism to act as a parking brake for a vehicle or as a load holding mechanism on a game, the handle is moved

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in the opposite direction and the control 89 rotates in the opposite direction so that it moves radially inward. Due to the threaded connection between the portion 91 and the threaded portion 77, the inward movement of the controller 89 forces the support member 85 radially inwardly. The inward movement of the support member 85 guides the locking member 81 into its radially innermost position, as shown in FIG.

2. In this set position, however, the locking means 81 is now held in its innermost position, and as the toothed wheel 27 orbits one of its external teeth enters the nearest working chamber. Instead of the outer tooth of the gear 27 causing the working chamber to assume its minimum volume, as in normal operation, the outer tooth hitting the locking means 81 and 15 will be prevented from moving further into the working chamber.

Thus, continued circular motion of the sprocket 27 is impeded, as is the rotational movement of the sprocket relative to the sprocket 23.

It will be appreciated that the aforementioned method of operation will be the same in any cogwheel where there is a relative circular and rotary movement between the cog 27 and the ring 23, irrespective of which of the parts takes part in the motion. It is e.g. It is known that the sprocket 27 only rotates while the sprocket 23 only rotates 25 and other combinations are also known. The locking mechanism of the invention can be used in a gearwheel machine using any of the possible combinations of relative orbital and rotational motion.

It is noted that according to the invention, the magnitude of the radial movement of the locking means 81, the operating mechanism 83 and the supporting means 85 between the idle and the operative position is quite small. Typically, a radial motion less than 2.54 mm is sufficient, and in the present embodiment, only a motion 35 of 1.53 mm is required. It will be understood that the magnitude of the radial motion required in each case is 10

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depending on the design of the present gear wheel machine.

In FIG. 4, the invention is shown to be used in connection with an alternative form of a 5-pressure fluid driven machine. In the embodiment of FIG. 4 are parts similar to those of FIG. 2 with the same reference numeral plus 100, while completely new elements have reference numerals starting with 101. The motor or machine of FIG. 4 accordingly has a housing 101, 10 in which is provided a plurality of bolts 111. Inside the housing 101 is arranged the tooth ring 123 with internal cylindrical or roller teeth 125. An externally toothed gear 127 is mounted eccentrically in the ring 123 and the relative circular and rotary movement between the gear ring 123 and the gear wheel 127 is the same as in the embodiment of FIG. 2. In the embodiment of FIG. 4, however, the internally toothed gear 127 performs only a rotary motion, while the ring 123 performs only an orbital motion.

In the housing 101 are formed a number of semi-circular recesses, each receiving a roller 103. The ring 123 has around its outer periphery a number of arcuate recesses 105, each corresponding to one of the rollers 103. As is well known, fluid to and from the expanding and contracting working chambers 129 cause the ring 123 to perform a circular motion, while the engagement of the rollers 103 in the recesses 105 prevents the ring 123 from rotating so that only rotational movement of the externally toothed gear 127 is possible. .

The housing 101 has a cam 171 in which is formed a bore 173 including a bore 175 and a threaded portion 177. A bore 173 is provided with an operating mechanism 183 with a support member 185 with an end face 187. The operating mechanism 183 further includes a control means. 189 with a threaded portion 191, a grooved portion 193 and another threaded portion 11

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195. The parts just described may be formed in the same manner as the corresponding parts in the embodiment of FIG. 2nd

By operating the operating mechanism 183 in the same way as in the embodiment of FIG. 2, the nearest roller is moved radially inwardly so that this roller acts as a locking means 181. When the locking means 181 is in its activated position, normal circular movement of the ring 123 is obstructed and the normal rotating movement of the gear 127 is therefore also hindered.

Although in the preferred embodiment, rotation of a threaded member is used to induce the radial movement of the locking member 81, it is obvious that other methods may be used to induce the steering movement. Eg. For example, fluid may be pressurized to the upper end of the support member 85 to force it and the locking member 81 inwardly into the effective locking position. Other mechanical devices may also be used to move the locking member inward.

It will be appreciated that the invention provides a simple, inexpensive and effective way of locking the gear displacement mechanism so as to provide an effect such as by a parking brake or by a mechanism to maintain a load in a hoist. By the invention, it has become possible to achieve this without mounting additional sections on the motor, and as shown in the embodiment of FIG. 2 only a change of the internal toothed ring 23 is required, while all other 30 parts are the same as in a standard motor. Thus, it has become possible in the present invention to provide a motor with a motor lock or brake without appreciably increasing the dimensions or weight of the motor or of the space occupied by the motor.

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Claims (7)

A gearwheel, particularly a hydraulic gear motor, having a planet gear housing (17,101) with an internally toothed ring (23,123) and an externally toothed gear 5 (27,127) located eccentrically in the internally toothed ring, which toothed elements perform one relative circular and rotary movement, their teeth engaging with each other and during their movements forming expanding and contracting working chambers (29,129), a distributor valve (19,55) adapted to set depending on one of said movements a fluid inlet (57) associated with one of the expanding and contracting working chambers (29,129) and a fluid outlet in connection with another of the working chambers, and a power transmission shaft 15 (31) and a shaft shaft (41) adapted to transmit torques between the power transmission shaft (31) and one of said toothed elements, characterized by: a) a substantially cylindrical locking member (8) 1,181), which is radially movable in the planet wheel housing (17,101) in the direction of one of the toothed elements (27,127) and whose longitudinal axis is substantially parallel to the toothed element performing a rotary motion, (b) an operating mechanism (83,183) arranged to move the locking means (81) between a first position where it is outside the plane of the planetary motion of the orbiting toothed element (27 or 123) and a second position where the locking means (81,181) is inserted into the said web and may engage in external axial tooth spaces 30 or recesses (105) on the orbiting toothed member (27 or 123). Gear unit according to claim 1, characterized in that the locking means (81) is arranged at least partially in one of said working chambers (29) and in its first position permits normal circular and rotational movement of the gear (27). , and in its second position, extends sufficiently long into the work chamber (29) to engage one of the external teeth of the sprocket (27) as the work chamber approaches its minimum volume state . Gear unit according to claim 1, characterized in that the gear ring (23) is formed with a recess (79) which is circumferentially arranged between a pair of adjacent internal teeth and that the locking means (81) is arranged in at least partially in the recess and is 10 radially movable therein. Gear unit according to claim 1, characterized in that the operating mechanism (83) includes a substantially radial bore (73) in the internally toothed element (23) and adjustment means 15 (5,89) arranged in the bore for moving the locking means (81) between its first and second positions. Gear unit according to claim 1, characterized in that the movement of the locking means (81) between the first and second positions is less than 2.54 mm. Gear unit according to claim 4, characterized in that the adjusting means include an external threaded guide (89) which is in such threaded connection with the radially extending bore (73) that rotation of the control means causes a radial movement thereof between the first and other position. Gear unit according to claim 6, characterized in that the operating mechanism includes a support means (85) adapted to transmit a radially inward movement of the control means (89) to the locking means 30 (81), the supporting means including substantially preventing leakage of fluid from the working chamber (29) through the radially extending bore (73).