JPS6128902Y2 - - Google Patents

Description

[Detailed explanation of the invention] A. Purpose of the invention (1) Industrial application field The invention consists of a multi-plunger type hydraulic pump, a hydraulic pump arranged concentrically surrounding the hydraulic pump, and hydraulically connected to the hydraulic pump. The system consists of a multi-plunger type hydraulic motor, which provides reciprocating motion to the motor plunger of the hydraulic motor, and by changing the tilt angle of the motor swash plate, the reciprocating stroke and therefore the capacity of the hydraulic motor can be adjusted steplessly. The present invention relates to a hydraulic continuously variable transmission device.

(2) Prior Art The above-mentioned hydraulic continuously variable transmission device includes a hydraulic pump in which a plurality of pump plungers in an annular arrangement surrounding the rotation center of the pump cylinder connected to an input shaft are slid together; A hydraulic motor comprising a motor cylinder arranged concentrically surrounding a cylinder and a number of motor plungers arranged in an annular manner surrounding the center of rotation of the motor cylinder; a hydraulic motor fixedly installed inside the motor cylinder and the pump; a distribution board that is in relatively rotatable contact with the cylinder and controls the delivery and reception of hydraulic oil between the pump cylinder and the motor cylinder; is fixedly installed on the motor cylinder, and is connected to each of the pump plungers as the relative rotation between the distribution board and the pump cylinder rotates; a pump swash plate that provides reciprocating motion; a motor that is tiltably pivoted on a fixed transmission case, that provides reciprocating motion to each of the motor plungers as the motor cylinder rotates, and that can arbitrarily adjust the reciprocating stroke; A type consisting of a swash plate and a swash plate is conventionally known.

The motor cylinder of this type of transmission has a support hole for the motor plunger and a support part for the pump swash plate, both of which are precision machined, and an output gear must be provided at the end, so machining is extremely difficult. It has a difficult structure and shape.

Therefore, in order to be able to process motor cylinders easily and with high precision, for example,
As shown in Publication No. 6705, the motor cylinder is
Conventionally, it has been proposed that the pump is divided into at least two parts: a cup-shaped first part that supports the pump swash plate and through which the input shaft passes through the center, and a cylindrical second part that has a support hole for the motor plunger. ing.

(3) Problems to be solved by the invention In the conventional device, a connecting flange integrally formed at the inner end of the first portion and having the same diameter as the second portion is connected to the second portion.
Since the bolts were tightened to the end faces of the parts, the connecting flange itself could not function as a positioning member for the second part, so a dedicated positioning protrusion was provided at the inner end of the first part, separate from the connecting flange. Since it must be provided, there is a problem that the structure of the inner end of the first portion becomes complicated.

In addition, in the conventional device, the output shaft of the motor cylinder is integrally formed with the outer end of the second portion, so that the reaction torque from the pump plunger and the motor plunger acts intensively during rotation of the motor cylinder. The area near the pump swash plate of the motor cylinder and the area around the motor plunger support hole,
The motor cylinder is separated from the output shaft in the axial direction, a large torsional moment acts on the intermediate portion, and the load burden on the intermediate portion is large. This is a problem that cannot be overcome due to the strength of the transmission, and since the output shaft is placed on one side of the transmission in the axial direction and the input shaft is placed on the other side, it is difficult to connect the engine and transmission, for example. If such a system is installed, it is difficult to extract power from the intermediate portion, which is extremely disadvantageous when applied to a general automobile in which a differential mechanism is located between the engine and the transmission.

The present invention has been proposed in view of the above, and an object of the present invention is to provide a hydraulic continuously variable transmission capable of eliminating all of the above-mentioned defects and disadvantages of the conventional ones.

B. Structure of the invention (1) Means for solving the problem In order to achieve the above object, the present invention provides a hydraulic continuously variable transmission of the above type, in which the motor cylinder supports the pump swash plate. The center portion includes a cup-shaped first portion through which the input shaft passes, and a cylindrical second portion having a support hole for the motor plunger.
divided into at least two parts, said first
The output shaft having a gear is integrally formed on the outer end of the part, and a connecting flange is integrally formed on the inner end of the part, and the connecting flange is provided with a positioning member provided on the end surface of the second part opposite to the flange. The connecting flange and the positioning recess are closely fitted in the recess to coaxially align the first and second parts, and are connected to the second part by a connecting bolt, and the connecting flange and the positioning recess are
It is characterized by having a diameter larger than the diameter of the inscribed circle of the support hole group of the motor plunger and smaller than the diameter of the circumscribed circle thereof.

(2) Effect The first and second parts can be easily positioned by simply fitting the connecting flange at the inner end of the first part directly into the positioning recess on the end face of the second part.

Since the area near the pump swash plate of the motor cylinder or the area around the motor plunger support hole and the output shaft can be placed close to each other in the axial direction, it is possible to make torque transmission possible without creating a large torsional moment between them. Furthermore, since the area around the motor hydraulic chamber of the motor cylinder and the distribution board are spaced apart from the output shaft and not in the torque transmission path, the load burden is reduced.

(3) Embodiment An embodiment of the present invention will be described below with reference to the drawings. Reference numeral 1 denotes a transmission case formed by joining two case halves 1a and 1b divided in the longitudinal direction, and a transmission case equipped therein. The device is composed of a hydraulic pump P and a hydraulic motor M.

The hydraulic pump P includes a pump cylinder 4 which is passed through the input shaft 2 and is spline-coupled 3 thereto.
The pump cylinder 4 is composed of a plurality of cylinder holes 5, 5... arranged in an annular arrangement surrounding the rotation center of the pump cylinder 4, and a large number of pump plungers 6, 6... which are slidably engaged with each other. Power from an engine (not shown) is transmitted via the flywheel 7. On the other hand, the hydraulic motor M has a motor cylinder 8 disposed so as to concentrically surround the pump cylinder 4 and rotate relative thereto.
and a large number of motor plungers 10, 10, . . . which are slidably engaged with a plurality of annularly arranged cylinder holes 9, 9, .

A support shaft 11 is provided on both axial end surfaces of the motor cylinder 8.
and an output shaft 11' are provided protrudingly, and the support shaft 11 is connected to the right case half 1b via a ball bearing 12.
The output shaft 11' is supported via a needle bearing 13 by the end wall of the left case half 1a. A stop ring 14 that clamps the inner race 12a of the ball bearing 12 together with the motor cylinder 8 is locked to the outer end of the support shaft 11, and another stop ring 15 is locked to the outer end of the outer race 12b on the right side. The outer race 12 is engaged with the annular recess 16 on the outer surface of the end wall of the case half 1b.
A retaining plate 17 that abuts the outer end of the right case half 1b is removably fixed to the right case half 1b by bolts 18, thus preventing the ball bearing 12 and the support shaft 11 from moving in the axial direction with respect to the right case half 1b.

A gear 19 is integrally formed on the output shaft 11', and the output of the hydraulic motor M is taken out from the gear 19 and transmitted to a differential gear device 21 via an intermediate gear 20. There is. A pump swash plate 22 that is inclined at a certain angle with respect to each pump plunger 6 is fixed inside the motor cylinder 8, and a sliding piece 6a that can smoothly slide on the surface of this pump swash plate 22 is attached to each pump plunger. The pump swash plate 22 is swingably attached to the spherical end of the pump plunger 6, and thus the pump swash plate 22 can give reciprocating motion to each pump plunger 6 as the pump cylinder 4 rotates, thereby repeating the suction and discharge strokes.

Further, a motor swash plate 23 is pivotally supported in the transmission case 1 so as to be tiltable via a pair of trunnion shafts 24 protruding from both outer sides of the motor swash plate 23, facing each motor plunger 10. A sliding piece 10a that can smoothly slide is attached to the spherical end of each motor plunger 10 so that the motor swash plate 23 can swing freely.
As the motor plungers 10 rotate, each motor plunger 10 is given reciprocating motion to repeat the expansion and contraction strokes. At that time, the stroke of the motor plunger 10 moves the motor swash plate 23 to each motor plunger 1.
Adjustment from zero to maximum can be made steplessly by tilting from an upright position perpendicular to zero to the maximum tilted position shown.

A hydraulic closed circuit is formed between the hydraulic pump P and the hydraulic motor M via a distribution panel D and a distribution ring 25, which will be described later. Therefore, the input shaft 2 is connected to the pump cylinder 4.
When rotating the pump plunger 6 in the discharge stroke
High-pressure hydraulic oil discharged from the cylinder hole 5 housing the motor plunger 10 is fed to the cylinder hole 9 housing the motor plunger 10 on the expansion stroke, while being discharged from the cylinder hole 9 housing the motor plunger 10 on the contraction stroke. The hydraulic oil is returned to the cylinder hole 5 that accommodates the pump plunger 6 on the suction stroke, and during this period, the reaction torque that the pump plunger 6 on the discharge stroke gives to the motor cylinder 8 via the pump swash plate 22;
The motor plunger 10 in the expansion stroke is connected to the motor swash plate 2.
The motor cylinder is rotated by the sum of the reaction torque received from 3.

In this case, the gear ratio of the motor cylinder 8 to the pump cylinder 4 is given by the following equation.

Speed ratio = rotation speed of pump cylinder 4 / rotation speed of motor cylinder 8 = 1 + capacity of hydraulic motor M / capacity of hydraulic pump P As is clear from the above equation, change the capacity of hydraulic motor M from zero to a certain value. For example, the gear ratio can be changed from 1 to a certain required value. Incidentally, since the capacity of the hydraulic motor M is determined by the stroke of the motor plunger 10, the gear ratio can be changed from 1 to a certain value by tilting the motor swash plate 23 from the upright position to a certain inclination angle as described above. Can be adjusted in stages. A hydraulic servo motor S ₁ is provided in the mission case 1 for tilting the motor swash plate 23 .

The motor cylinder 8 is composed of first to fourth parts 8a to 8d divided in the axial direction.

The first portion 8a has a cup shape and is integrally provided with the output shaft 11' having a gear 19 at its outer end,
The pump swash plate 22 is supported on the inner end surface.

The second portion 8b has a cylindrical shape, and a support hole 9a for the motor plunger 10 in the cylinder hole 9 is provided along the entire length of the second portion 8b, and the pump cylinder 4 is accommodated in the hollow portion thereof. The third portion 8c has a disk shape, and the fourth portion 8d has a ring shape, and these have a support hole 9a of the cylinder hole 9.
A series of motor hydraulic chambers 9d having a slightly larger diameter are provided, and a distribution board D is formed by the central disc-shaped portion of the third portion 8c.

A connecting flange 26 is integrally provided on the first portion 8a at an end opposite to the second portion 8b, and the flange 26 is tightly fitted into a positioning recess 27 on the end face of the second portion 8b opposite thereto. The portions 8a and 8b are coaxially aligned. In this case, the connecting flange 26
The positioning recess 27 has a diameter D _{1 of the inscribed circle of the support hole 9a group, which is larger than D 1} and a diameter D ₂ of the circumscribed circle.
A notch hole 46 is provided in the connecting flange ₂₆ to avoid interference with the pump plunger 6. and,
This connecting flange 26 is connected to a plurality of connecting bolts 28
is fixed to the second portion 8b.

Also, the second, third and fourth portions 8b, 8c, 8
d has knock pins 29, 30 at their respective joints.
The second and fourth parts 8b, 8 are inserted into each other and positioned mutually, and the second and fourth parts 8b, 8 are connected by a plurality of connecting bolts 31.
d are tightly connected, and the third portion 8c is firmly held between them, and thus the first to fourth portions 8
a to 8d are joined together.

The input shaft 2 is supported at its outer end at the center of the support shaft 11' via a needle bearing 32, and at its inner end at the center of the distribution board D via a needle bearing 33, A compression spring 57 is accommodated in an annular spring chamber 56 formed adjacent to the spline joint 3 between the opposing peripheral surfaces of the input shaft 2 and the pump cylinder 4, and the right end of the spring 57 is locked to the pump cylinder 4. Seat plate 58
and a seat plate 59 whose left end is locked to the input shaft 2.
make contact with each other elastically. On the other hand, input shaft 2
A stopper plate 60 facing the inner end surface of the motor cylinder 8 is engaged with a portion protruding from the left end surface of the pump cylinder 4, and a needle thrust bearing 61 is interposed between these opposing surfaces. Therefore, the elastic force of the spring 57 presses the pump cylinder 4 against the distribution board D via the seat plate 58 to prevent oil leakage from their rotating and sliding parts, and the reaction force of the elastic force is transmitted to and supported by the motor cylinder 8 via the seat plate 59, input shaft 2, stopper plate 60 and needle thrust bearing 61.

The support plate 17 has a support shaft 1 of the motor cylinder 8.
A fixed shaft 35 passing through D 1 is connected via a pin 36 , and a distribution board D is connected to the inner end of this fixed shaft 35 .
A distribution ring 25 in contact with the motor cylinder 8 is eccentrically supported by the distribution ring 25.
The hollow portion 37 of d is divided into an inner chamber 37a and an outer chamber 37b. On the other hand, the distribution board D is provided with discharge and suction ports 38 and 39, and the discharge port 38 communicates between the cylinder hole 5 of the pump plunger 6 in the discharge stroke and the inner chamber 37a, and the suction port 39 between the cylinder hole 5 of the pump plunger 6 in the suction stroke and the outer chamber 3
7b are communicated with each other. Further, the distribution panel D is provided with a number of radially extending communication ports 40, 40..., which communicate the motor hydraulic chambers 9b, 9b... of the motor cylinder 8 with the inner chamber 37a or outer chamber 37b. be done.

Therefore, when the pump cylinder 4 rotates, high-pressure hydraulic oil generated by the discharge stroke of the pump plunger 6 is transferred from the discharge port 38 to the inner chamber 37a.
Further, the hydraulic oil flows into the motor hydraulic chamber 9b of the motor plunger 10 in the expansion stroke through the communication port 40 in communication with it, giving thrust to the plunger 10, while the hydraulic oil discharged by the motor plunger 10 in the contraction stroke It flows back to the cylinder hole 5 of the pump plunger 6 in the suction stroke through the communication port 40 and the suction port 39 that communicate with the outer chamber 37b, and due to this circulation of hydraulic oil, the hydraulic oil is transferred from the hydraulic pump P to the hydraulic motor M as described above. transmission is performed.

The fixed shaft 38 has a center hole 41 and a plurality of (two in the figure) short-circuit ports 42 passing through the side wall of the center hole 41.
43, the inner ends of these shorting ports 42, 43 are connected to the inner chamber 7a via the center hole 41,
Further, their outer ends are the outer grooves 44, 4 of the fixed shaft 35.
5 to the outer chamber 37b, and these short-circuit ports 42, 43 are opened and closed by rightward and leftward movement of a clutch valve 48 that slides into the center hole 41. That is, when the clutch valve 48 is in the rightward movement position, the short-circuit ports 42 and 43 are opened to communicate between the inner and outer chambers 37a and 37b, and the hydraulic oil discharged from the discharge port 38 of the distribution board D is immediately discharged. Since the suction port 39 is short-circuited and hydraulic oil is not supplied to the hydraulic motor M, the hydraulic motor M
is in a so-called clutch-off state, and then the clutch valve 48 is moved to the left to close the short-circuit port 4.
When both 2 and 43 are closed, the hydraulic oil is circulated from the hydraulic pump P to the motor M, resulting in a clutch-on state.

A valve rod 50 is screwed onto the tip of the clutch valve 48, and an umbrella-shaped valve body 51 is swingably connected to its spherical end 50a.
8 can be brought into close contact with the distribution board D so as to close the discharge port 38 when it moves to the left beyond the clutch-on position. The discharge port 38 is closed by the valve body 51 when the motor swash plate 23 is placed in an upright position and the gear ratio is set to 1:1. The motor cylinder 8 can be mechanically driven via the pump plunger 6 group and the pump swash plate 22, so the thrust applied to the motor swash plate 23 of the motor plunger 10 disappears, reducing the burden on each part due to the thrust. It can be reduced.

For sliding operation of the clutch valve 48, a hydraulic servo motor _S2 is provided on the fixed shaft 35.

A supply pump F is mounted on the outside of the left half case 1a. The pump is driven by the input shaft 2 to draw in oil from an oil reservoir (not shown) to generate hydraulic oil at a constant pressure. The discharge port 52 of the pump F is connected to the oil passage 53 in the input shaft 2 and further to the distributor D via check valves 54 and 55.
and the outer chamber 37b. Therefore, when hydraulic oil leaks from the hydraulic closed circuit of the hydraulic pump P and the hydraulic motor M, the leakage can be automatically replenished by the replenishment pump F.

C. Effect of the invention As described above, according to the invention, the connecting flange 2 at the inner end of the cup-shaped first portion 8a of the motor cylinder 8
6, the cylindrical second portion 8b of the motor cylinder 8
Since the first and second portions 8a and 8b can be easily positioned simply by directly fitting them into the positioning recesses 27 on the end faces, the connecting flange 26
The inner end of the first portion 8a also functions as a positioning protrusion, which makes the structure of the inner end of the first portion 8a simple and easy to process.

Further, the diameter D ₃ of the connecting flange 26 and the positioning recess 27 is set to be larger than that D ₁ of the inscribed circle of the group of support holes 9 a of the motor plunger 10 and smaller than that D ₂ of the circumscribed circle of the group of support holes 9 a of the motor plunger 10 . The large diameter connecting flange 26 can be used without reducing the entire length of the support hole 9a by the positioning recess 27. Therefore, the support for the motor plunger 10 during the expansion stroke where the amount of overhang from the motor cylinder 8 is particularly large is improved. The connection between the first and second portions 8a and 8b of the motor cylinder 8 can be reliably and firmly established.

Further, an output shaft 11' is provided at the outer end of the first portion 8a.
is formed, so during the rotation of the motor cylinder 8,
The area between the output shaft 11' and the vicinity of the pump swash plate 22 of the motor cylinder 8 and the vicinity of the motor plunger support hole 9a, where the reaction torque from the pump plunger 6 and the motor plunger 10 acts intensively, respectively, is axially moved. They can be placed close to each other, and therefore torque can be easily transmitted between them without creating a large torsional moment. Furthermore, the area around the motor hydraulic chamber 9b of the motor cylinder 8 and the distribution board D can be placed close to each other. Since it is separated from the output shaft 11' and is not in the torque transmission path, the load burden is significantly reduced, and even if the capacity of the many oil passage spaces formed therein is increased, the strength of the motor cylinder 8 is It's not really a problem. Moreover, since it can be inserted into one side of the transmission in the axial direction and the output shafts 2 and 11' can be arranged together, for example, when the engine and transmission are connected, power can be taken out from the middle part of the engine and the transmission. This is advantageous when applied to general automobiles in which a differential mechanism is disposed between the transmission and the transmission.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional side view of an embodiment of the device of the present invention;
FIG. 2 is a sectional view taken along the line -- in FIG. 1. 1...Mission case, 2...Input shaft, 4...
...Pump cylinder, 6...Pump plunger, 8
...Motor cylinder, 8a...First part, 8b...
...Second part, 9a...Bearing hole, 10...Motor plunger, 11'...Output shaft, 19...Gear, 2
2...Pump swash plate, 23...Motor swash plate, 26...
...Connection flange, 27... Positioning recess, 28...
...Coupling bolt, D...Distribution board, _D1 ...Diameter of the inscribed circle of the motor plunger support hole group, _D2 ...Diameter of the circumcircle thereof, _D3 ...Diameter of the connecting flange and positioning recess, M... Hydraulic motor, P...hydraulic pump.

Claims (1)

[Scope of utility model registration request] A large number of pump plungers 6 are arranged in an annular manner surrounding the rotation center of the pump cylinder 4 connected to the input shaft 2.
a hydraulic pump P formed by sliding a motor cylinder 8 connected to the output shaft 11' and arranged so as to concentrically surround the pump cylinder 4; and a large number of motor plungers 10 in an annular arrangement surrounding the rotation center of the motor cylinder 8;
and a hydraulic motor M formed by slidingly connected to each other; fixedly installed inside the motor cylinder 8 and in relatively rotatable contact with the pump cylinder 4 to control transfer of hydraulic oil between the pump cylinder 4 and the motor cylinder 8. a distribution board D; a pump swash plate 22 that is fixed to the motor cylinder 8 and provides reciprocating motion to each of the pump plungers 6 as the pump cylinder 4 rotates relative thereto; a fixed transmission case 1;
a motor swash plate 23 which is tiltably supported on the motor cylinder 8, gives reciprocating motion to each of the pump plungers 10 as the motor cylinder 8 rotates, and can arbitrarily adjust the reciprocating stroke; In the device, the motor cylinder 8 has a cylindrical shape that supports the pump swash plate 22 and has a cup-shaped first portion 8a in the center through which the input shaft 2 passes, and a support hole 9a for the motor plunger 10. Second
The first part 8a is integrally formed with the output shaft 11' having the gear 19 at its outer end, and the connecting flange 26 at its inner end. The connection flange 26 is connected to the second
The first and second parts 8a and 8b are coaxially aligned by closely fitting into the positioning recess 27 provided on the end surface of the part 8b, and the connecting bolt 28 is attached to the second part 8b.
The connecting flange 26 and the positioning recess 27 are connected to each other by a hydraulic non-operator having a diameter D ₃ larger than the diameter D ₁ of the inscribed circle of the group of bearing holes 9a of the motor plunger 10 and smaller than the diameter D ₂ of the circumscribed circle thereof. gear transmission.