PUMP OR MOTOR WITH AT LEAST ONE PISTON BODY PROVIDED IN A CYLINDRICAL HOUSING

Abstract: Pump or motor comprising at least one cylindrical housing (4, 30, 50) being closed at both ends and a piston body (5, 35, 51) received in said housing so that at both ends of said housing a working compartment (14, 46, 72) is formed, said piston body being provided with a cavity shaped such that in it one piston rod (11, 42, 57) can be received, one end of which is connected to the piston body and the other end to a crankshaft (2, 41, 59) which can pass through the piston body.

Description: Pump or motor with at least one piston body provided in a cylindrical housing. The invention relates to a pump or motor comprising: at least one piston body; a cylindrical housing in which said piston body may reciprocate; a cover for closing of said housing for obtaining a closed compartment between said piston body and said housing; a piston rod connected to said piston body; a shaft rotatably supported by said housing and running in transverse direction in respect of the direction of movement of said piston body; and connecting means between said shaft and said piston rod for converting either a rotational movement of said shaft into a rectilinear movement of said piston body or a rectilinear movement of said piston body into a rotational movement of said shaft or of a part cooperating with this. A pump of the type described above can be used for compressing fluids, in particular for obtaining high pressures and when no large volumes have to be transported. In case of a motor of the type described above a mixture of air and fuel is combusted in the closed compartment by means of a sparking plug, mounted in the cylinder cover. By this the piston body is brought into movement, said movement being converted into a rotational movement of the shaft. In case of the known pumps and motors mostly the cylindrical housing is connected to a crankcase supporting said shaft which is shaped as a crankshaft and the piston rod is pivotally connected to said crank¬ shaft and to said piston body. Such a construction is relatively cumbersome because only one end surface of the piston is used and the length of the piston has to be such large that tilting of the piston is opposed as much as possible. By US-A-4 , 013, 048 a motor is known comprising two piston bodies provided in two cylindrical housings being in coaxial alignment with each other. Both piston bodies are provided with a piston rod which is fixedly connected to the related piston, the free ends of said rods being connected to a yoke housing provided with a central slot in transverse direction to the center line of the cylindrical housings, in which slot the crank of a crankshaft is moving. This also brings a cumbersome construction with it as well as an unfavourable loading of some parts of the motor. Now the object of the invention is to remove these disadvantages and to this end a pump or motor according to the invention is characterized in that both ends of said substantially cylindrical housing are closed off for forming a working compartment at either side of said piston body, said piston body being provided with a cavity which is shaped such that in it one piston rod can be received and that the crankshaft can pass through the piston body. According to one embodiment of the invention the cylindrical housing is provided in a cylindrical rotor, the axis of which is running transverse to the axis of said cylindrical housing, said rotor being rotatably supported by a casing in which the crankshaft is fixedly mounted such that a rotational movement of said rotor is converted into a reciprocating movement of said piston body in said cylindrical housing or vice versa. A very stable construction can be obtained when the crankshaft is provided with an excentrically mounted circular disk and said piston rod is having an angular portion being supported by said disk. In case of such an embodiment the shaft can run through as one entire whole and can better transfer the loads exerted on it. According to a further embodiment the piston body is at least at one end of it provided with an additional piston rod in coaxial alignment with the cylindrical housing and fixedly connected to said piston body and sealingly extending through the related cylinder cover, said piston rod being connected to a secundary piston which may reciprocate in a secundary housing mounted to the cylindrical housing. Obviously said secundary piston will move together with the main piston body and can be used e.g. for compressing air for the combustion mixture or for pumping lubricant being used in the pump or motor itself. According to an embodiment of the invention the piston body is shaped by two spaced-apart pistons being connected by screwthreaded bolts provided with nuts and positioned outside the center line of said piston body. In this way the piston body can be assembled in a simple way by connecting two pistons by means of a number of bolts. According to an other embodiment the piston body is shaped by two spaced-apart pistons being connected by an intermediate piston with a larger diameter and being guided by a cooperating enlarged portion of the * cylindrical housing. In this way the dimensions of the crankshaft can be enlarged without enlarging the diameter of the two pistons forming part of the piston body. In this case also an auxiliary piston rod can be provided running parallel to the center line, of said intermediate piston and being connected near the circumference of this, said auxiliary piston rod extending in a secundary cylindrical housing provided besides the housing of the main piston body and being connected to a secundary piston reciprocating in said secundary cylindrical housing. So said secundary piston and the housing for it can be positioned besides the main cylindrical housing so that the length of the pump or motor will not be increased. Two or more pumps or motors according to the invention can easily be coupled to each other by placing the cylindrical housings of it besides each other so that the crankshafts of these are in line with each other and can be connected to each other, the axes of the housings being positioned in parallel planes and being parallel to or are making an angle with each other, means being present to connect the housings to each other. Obviously in this way the capacity of a device can be increased in a very simple way. Now the invention is described on hand of embodiments shown in the drawing, in which: Fig. 1 schematically shows a section of an embodiment of a pump according to the invention in which the piston body is received in a rotor which is rotatably mounted in a housing; Fig. 2 schematically shows a part of a section according to the line II-II of Fig. 1; Fig. 3 schematically shows partially in section and partially in side view a motor according to the invention; Fig. 4 schematically shows a partial side view and a partial section of the motor of Fig. 3 in a direction transverse to Fig. 3; Fig. 5 schematically shows a section according to the line V-V of Fig. 3; Fig. 6 schematically shows a combination of two pumps or motors according to the invention; Fig. 7 schematically shows partially in section and partially in side view a pump according to the inven¬ tion provided with secundary pistons movable in secundary housings; and Fig. 8 schematically shows partially in side view and partially in section a two-stroke diesel engine. The pump shown in the Figs. 1 and 2 comprises a housing 1 in which one end of a shaft 2 is fastened. In the housing 1 the rotor 3 is rotatably supported and can be driven from the outside of the housing in a not further indicated way. The rotor 3 e.g. can be provided with a hollow shaft surrounding the shaft 2. In the rotor 3 the cylindrical housing 4 is provided in which the piston body 5 can reciprocate. The piston body 5 comprises the cylindrical portion 6 and the bottoms 7 and 8. The bottom 8 is provided with lugs 9 for taking up a piston pin 10 to which one end of a piston rod 11 is connected, the other end of this rod being provided with an angular portion 12 rotatable mounted on a circular disk 13 which is fixedlv connected to the shaft 2 . Obviously when the rotor 3 is rotated the piston body 5 will reciprocate in the housing 4 so that the volume of the compartment 14, present between the piston bottom 7 and the housing 1 will decrease and ultimately will have the volume of the compartment 14A between the piston bottom 8 and the housing 1. "So the pump according to the Figs. 1 and 2 will work as compressor. In the known way the piston body 5 will be provided with piston rings 15 for sealing the compartments 14 and 14A and with a cavity 16 for receiving the piston rod and other parts. The cavity 16 comprises two slots 17 in the cylindrical portion 6 through which slots the shaft 2 can pass. Supplying fluid to a compartment takes place by means of the supply opening 18 in the housing 1 said opening debouching into the groove 19. The compressed fluid leaves the compartment via a groove 20 and the outlet opening 21. The sealing between the cylindrical surfaces of the housing 1 and the rotor 3 can take place by means of the sealing strips 22 and by further circumferential strips between the radial faces of the housing 1 and the rotor 3. A lubricant container 23 can be present provided with an outlet 24 for supplying lubricant to the engaging surfaces of housing 1 and rotor 3, the cylindrical housing 4 and the piston body 5 and the engaging portions of piston pin 10, piston rod 11, circular disk 13 etc. To this a bore 25, an opening 26 and further means can be used. Obviously the supply opening 18 and the outlet opening 21 can be provided with check valves while between other parts roller or needle bearings can be provided, this all in the known way. The Figs. 3-5 show an embodiment of a motor according to the invention comprising a housing 30 having two cylindrical portions 31 and a connecting portion 32. Said connecting portion' 32 consists of the cylindrical portions 33 and extended portions 34. Fig. 5. In the housing 30 a piston body 35 is received comprising two cylindrical end portions 36 being connected to each other by four elongated portions 37, as appears in particular from Fig. 5. Through the opening between the parts 37 a shaft 38 may pass, being provided with two disks 39 between which a shaft 40 is mounted for obtaining a crankshaft 41. To the pin 40 one end of the piston rod 42 is connected, the other end of it is connected with the cylindrical The connecting portion 32 can be provided with an oil sump 43 and the disks 39 can take care for bringing oil to the moving parts. In the covers 44 valves 45 are mounted for either supplying a mixture of gas and fuel to the compartment 46 or for removal of the combustion gases. Said valves 45 can be controlled in a known way, e.g. by means of a cam mounted on the shaft 38, rocker arms and valve lifters, said parts not being indicated in the drawing. When the device according to the Figs. 3-5 is used as motor each cover 44 will be provided with a sparking plug in the known way. When the device is used as a pump no sparking plug is needed and the valves 45 possibly may be in the shape of simple check valves. Fig. 6 shows the possibility for assembling two devices according to the present invention having about the shape of the device shown in the Figs. 3-5, so that the same reference numbers are used for corresponding parts. In this case the houses 30 each are provided with a flange 47, the flanges being connected to each other by means of bolts 48. The shafts 38 of the two devices are connected to each other or are forming one part between the crank portions 39, 40. The device according to Fig. 7 comprises a cylindrical housing 50 in which the piston body 51 is incorporated consisting of two mainly cylindrical portions 52 being connected by means of four boults 53 having a collar 54 against which the portions 52 come to rest, nuts 55 being used ' to connect the portions 52 fixedly o the bolts 53. One of the portions 52 is provided with a piston pin 56 for connecting the piston rod 57 to the piston body 51. The other end of the piston rod 57 being connec¬ ted to the shaft 58 of the crank shaft 59. The housing 50 is supported by two supports 60 and further comprises the oil sump 61 in which a gear wheel pump 62 is mounted for supplying oil 63, present in the oil sump 61, to the places where this is needed. Both ends of the piston body 51 are connected to a secundary shaft 64 running through a sleeve 65 connected to the cover 66 of the housing 50. The other end of the shaft 64 is connected to a secundary piston 67 movable in a secundary housing 68 closed by covers 69. In the covers 66 valves 70 can be mounted and in the covers 69 valves 71. It is e.g. possible to connect outlet valves 71 with inlet valves 70 so that air being sucked into a compartment 72 can have a somewhat higher pressure than when it is directly sucked in from the surrounding. To this end it is e.g. possible to connect the two outlet valves 71 of the secundary housing 68 with an intermediate reservoir before the air from this is supplied to a compartment 72. As shown in Fig. 7 the housing 50 is divided into two sections being connected to each other by means of flanges 73 and boults 74. Fig. 8 shows a device the main portion of which equals that of the device of Figs. 3-5 so that correspon¬ ding parts are indicated with the same reference numbers. The device according to Fig. 8 comprises the housing 30 consisting of the two cylindrical portions 31 and the connecting portion 32. In the housing 30 the piston body 35 is received comprising two end portions 36 and the elongated connecting portions 37. The crank- shaft 41 is connected to the piston body 35 by means of the piston rod 42. The shape of the piston body 35 can be somewhat different from the piston body shown in Figs. 3-5 but this is not important. Fig. 8 shows that besides the housing portion 31 a secundary housing 80 is mounted in which the secundary piston 81 is moving which by means of the piston rod 82 is connected to the main piston body 35. By means of the secundary piston 81 air is sucked into the housing 80 by means of the valve 83, said air being compressed and being supplied to the inlet line 84 via the valve 85. From the inlet line 84 the compressed air is brought into the compartment 46 by means of the valve 86, being controlled by the rocket arm 87 and the valve lifter 88. In the compartment 46 fuel will be injected and the mixture of air and fuel will be combusted by means " of a glow plug, not being indicated. After the combustion of the fuel the combustion gases can leave the compartment 46 by means of the opening 89 and a good removal of the combustion gases can be obtained by opening the valve 86 so that an optimum filling of the compartment 46 can be reached. Obviously the left side of the housing 30, shown in Fig. 8, also can be provided with a secundary housing 80 as shown in the right side of said Figure. It will be obvious that only some possible embodiments of a pump or a motor according to the invention are shown in the drawing and are described above and that many modifications can be applied without leaving the inventive concept.

Claims: - C l a i m s - 1. Pump or motor comprising: at least one piston body; a cylindrical housing in which said piston body may reciprocate; a cover for closing of said housing for obtaining a closed compartment between said piston body and said housing; a piston rod connected to said piston body; a shaft rotatably supported by said housing and running in transverse direction in respect of the direction of movement of said piston body; and connecting means between said shaft and said piston rod for converting either a rotational movement of said shaft into a rectilinear movement of said piston body or a rectilinear movement of said piston body into a rotational movement of said shaft or of a part cooperating with this, characterized in that both ends of said substantially cylindrical housing (4,30,50) are closed off for forming a working compartment (14,46,72) at either side of said piston body (5,35,51) , said piston body being provided with a cavity which is shaped such that in it one piston rod (11,42,57) can be received and that the crankshaft (2,41,59) can pass through the piston body (15,35,51) . 2. Pump or motor according to claim 1, characterized in that the cylindrical housing (4) is provided in a cylindrical rotor (3) , the axis of which is running transverse to the axis of said cylindrical housing (4) , said rotor (3) being rotatably supported by a casing (1) in which the crankshaft (2) is fixedly mounted such that a rotational movement of said rotor (3) is converted into a reciprocating movement of said piston body (5) in said cylindrical housing or vice versa. 3. Pump or motor according to claims 1 or 2 , characterized in that the crankshaft (2,41,59) is provided with an excentrically mounted circular disk (13) and said piston rod (11) is having an angular portion (12) being supported by said disk (13) . 4. Pump or motor according to claims 1 or 3 , characterized in that the piston body (35,51) is at least at one end of it provided with an additional piston rod (64) in coaxial alignment with the cylindrical housing (50) and fixedly connected to said piston body (51) and sealingly extending through the related cylinder cover (66) r said piston rod (64) being connected to a secundary piston (67) which may reciprocate in a secundary housing (68) mounted to the cylindrical housing. (50) . 5. Pump or motor according to claims 1 to 4, characterized in that the piston body (51) is shaped by two spaced-apart pistons (52) being connected by screwthreaded bolts (53) provided with nuts (55) and positioned outside the center line of said piston body (51) . 6. Pump or motor according to claims 1 to 4, characterized in that the piston body (35) is shaped by two spaced-apart pistons (36) being connected by an intermediate piston (37) with a larger diameter and being guided by a cooperating enlarged portion (32) of the cylindrical housing (30) . 7. Pump or motor according to claim 6, characterized in that an auxiliary piston rod (82) is provided running parallel to the center line of said intermediate piston (37) and being connected near the circumference of this, said auxiliary piston rod (82) extending in a secundary cylindrical housing (80) provided besides the housing (30) of the main piston body (35) and being connected to a secundary piston (81) reciprocating in said secundary cylindrical housing (80) . 8. Pump or motor according to one of the preceding claims , characterized in that two or more pumps or motors are coupled to each other by placing the cylindrical housings (30) of them besides each other so that the crankshafts (38) of these are in line with each other an can be connected to each other, the axes of the hou¬ sings (30) being positioned in parallel planes and being parallel to or are making an angle with each other, means (47,48) being present to connect the housings (30) to each other.

Inventors: VAN LOO PIETER JOHAN, VAN LOO, PIETER, JOHAN
Applicants: WAAL H P BV, H.P. VAN DER WAAL B.V., I.O.
Application year: 1989
Main classification: F01B13
IPC codes: F01B9, F01B13, F02B3, F02B75