DK2817516T3 - Pump for a high-pressure cleaner and high-pressure cleaner - Google Patents

Description

The invention relates to a pump for a high-pressure cleaning appliance for conveying a cleaning liquid, the pump comprising a pump head having a main body in which a suction line and a pressure line connected to the suction line by at least one pump chamber are formed, a bypass line which connects the pressure line to the suction line, is aligned transversely to the pressure line and defines a pump plane with the pressure line, and also a delivery line, connected to the pressure line, for connecting an external liquid line, the pump head comprising an overflow valve which is arranged at the bypass line and the valve body of which is connected to a piston which enters the pressure line from the side located opposite the bypass line, delimits a section of a pressure chamber in flow direction with the delivery line via a pressure channel, and in dependence upon the liquid pressure in the pressure chamber moves the valve body for opening and closing the bypass line.

The invention also relates to a high-pressure cleaning appliance. A cleaning liquid, in particular, water can be pressurized and conveyed with such a pump. Water is supplied to the pump via the suction line, compressed in the pump chamber and discharged to the pressure line. Via the delivery line connected to the pressure line, the cleaning liquid can be discharged to an external liquid line, for example, a high-pressure hose, connected to the pump head. Arranged at the end of the liquid line is a pressure nozzle, for example, of a connected high-pressure pistol, which can be directed at an article to be cleaned. In order to reduce the mechanical load on the pump, the bypass line is provided, via which the conveyed cleaning liquid can be circulated in the pump. When the pressure nozzle is closed, a pressure surge occurs in the delivery line, which can be transferred via the pressure channel into the pressure chamber and acts upon the piston. The piston can lift off the valve body which, when the nozzle head is open, lies sealingly against a valve seat of the overflow valve. The bypass line is thereby released and cleaning liquid circulated. When the nozzle head is opened again, the pressure in the pressure chamber drops, and, usually under the force of a resetting element, the piston is transferred to its original position in order to displace the bypass line with the overflow valve. A pump of the kind mentioned at the outset, in which the pressure line and the bypass line are aligned transversely to each other and define a pump plane and the piston enters the pressure line from the side opposite the bypass line, is characterized by a compact flat construction using a small amount of material and by low machining and manufacturing costs. In the manufacture, the pump head is produced from the main body in which bores are made for formation of the respective fluid lines and fluid channels.

In pumps for high-pressure cleaning appliances, it is known to provide a pressure relief valve on the pressure line, with which the pressure in the pressure line can be reduced when a maximum permissible pump pressure is exceeded. This may, for example, occur when the overflow valve is faulty. It is also known in pumps for high-pressure cleaning appliances to provide a switch plunger for actuating an electric switch element with which a drive motor for the pump can be switched off when the pressure nozzle is closed. Such a switch plunger is arranged, for example, in an accommodation space which is in fluid connection with the pressure chamber so that the switch plunger can be actuated in dependence upon the liquid pressure in the pressure chamber.

Pumps for high-pressure cleaning appliances are described, for example, in EP 0 668 113 Al, in DE 39 36 155 A1 and in DE 10 2007 003 521 Al.

The object of the present invention is to further develop a pump of the kind mentioned at the outset, with which pump variations comprising a pressure relief valve or a switch plunger for actuating an electric switch element can be formed in a constructionally simple way.

This object is accomplished, in accordance with the invention, by a pump having the features of claim 1.

The attachment formed on the main body can already be formed on a blank for manufacture of the pump head and be machined in like manner in the construction of pump variants with pressure relief valve or switch plunger for actuating an electric switch element. The first attachment section defines a first axis which intersects the pressure line. During machining of the first axial section in preferably axial direction, a pump variant comprising a pressure relief valve can be formed in a constructionally simple way, in which a bore is made for accommodating the pressure relief valve. During machining of the second attachment section in preferably axial direction, a pump variant comprising a switch plunger for actuating an electric switch element can be formed in a constructionally simple way, in which a bore is made for accommodating the switch plunger. In particular, it is not necessary on account of the two machining variants to keep different blanks available for manufacture of the main body. This lowers manufacturing costs, for example, for tools, and storage costs. The first axis and the second axis of the two axial sections intersect each other at a point of intersection arranged outside of the pressure line and the pressure chamber. As a result, the attachment can be formed using only little material and allows cost-effective manufacture of the blank for the main body. Furthermore, when machining the main body for formation of the two pump variants, only little material has to be removed in order to form either a pump variant with pressure relief valve or a pump variant with switch plunger. This reduces the material waste and allows rapid and cost-effective machining of the blank.

The positioning of the point of intersection of the axes outside of the pressure line and the pressure chamber enables a compact arrangement of the attachment sections relative to each other. As a result, a compact construction of the respective pump variant can be achieved and the compact construction of the pump of the kind mentioned at the outset maintained.

It proves advantageous for the angle of intersection between the first axis and the second axis to be less than 90°, preferably less than 60°, even more preferred less than 30°. As a result, the attachment can be formed in a constructionally compact way using as small an amount of material as possible.

For example, in an advantageous embodiment of the pump in accordance with the invention, the angle is approximately 20°, in order to achieve a particularly compact construction.

It is advantageous for the first attachment section and the second attachment section to define the first axis and the second axis, respectively, on the basis of their outer contour. This makes it easier for a person performing the machining to machine the attachment. On the basis of the outer contour of the respective attachment section, the person performing the machining is already able to recognize the position and orientation of the axis defined by it.

The first attachment section and the second attachment section are preferably attachment sections which cross each other with a cylindrical or substantially cylindrical outer contour. As a result, the attachment sections and their machining directions along the axes respectively defined by them can be particularly easily recognized by the person performing the machining. For example, the attachment sections intersect each other at an angle of approximately 20°.

The first attachment section and the second attachment section are preferably attachment sections which intersect each other with a cylindrical or substantially cylindrical outer contour. This makes it even easier for a person performing the machining to recognize the respective attachment section and the machining direction along the axis defined by the attachment section.

It is expedient for at least one of the attachment sections to be arranged in the pump plane. This makes a compact, flat configuration of the pump head possible.

Preferably, both attachment sections are arranged in the pump plane, in order to achieve a particularly compact construction of the pump head.

If the first attachment section is arranged in the pump plane, its first axis expediently runs parallel to or in coincidence with an axis defined by the pressure line.

It is advantageous for the attachment to be formed on a side of the main body along which the bypass line extends, and for the overflow valve to be arranged between the attachment and a pressure line section of the pressure line, in which at least one outlet valve for sealing the at least one pump chamber relative to the pressure line is arranged. A compact construction of the pump head can thereby be achieved, in which the attachment and the pressure line section accommodating the at least one outlet valve are arranged on opposite sides of the bypass line and of the overflow valve.

In particular, it may be provided that the delivery line is aligned transversely to the pressure line. This facilitates the machining of the main body for formation of the delivery line.

It is advantageous for the delivery line and the bypass line to define a second pump plane aligned perpendicularly to the pump plane. Here the attachment and the pressure line are expediently arranged on opposite sides of the second pump plane and are arranged in the first pump plane so that a particularly compact configuration can be imparted to the pump head.

It is advantageous for the first attachment section to have an axial bore along the first axis, in which a pressure relief valve is accommodated, and for the bore to be connected to the pressure line via an overpressure channel. The formation of the axial bore in the first attachment section and of the overpressure channel for connection to the pressure line is made easily possible for a person performing the machining by the orientation of the first axis. The pressure relief valve ensures that a pressure in the pressure line exceeding a permissible pressure can be reduced. Liquid under overpressure can act through the overpressure channel upon the pressure relief valve so that it can be actuated and the overpressure discharged.

The overpressure channel can be formed in a constructionally simple way when it extends as an axial channel along the first axis.

For example, the overpressure channel can be connected to a section of the pressure line, in which the valve body of the overflow valve is arranged and from which the bypass line branches off. Expediently, the delivery line also branches off from the section of the pressure line.

It is advantageous for the second attachment section to have an axial bore along the second axis, in which a switch plunger is accommodated, and for the bore to be connected to the pressure chamber via a switch channel, the switch plunger being axially movable in dependence upon the pressure in the pressure chamber from a first switch position to a second switch position and vice versa for actuating an electric switch element. The formation of the axial bore in the second attachment section and of the switch channel for connection to the pressure chamber is made easily possible for a person performing the machining by the orientation of the second axis. The switch plunger can have on its side facing the switch channel an active surface which can be acted upon via the switch channel with the pressure in the pressure chamber, in order to transfer the switch plunger from a first switch position to a second switch position. The electric switch element can thereby be actuated, in order to switch off a motor driving the pump. Conversely, the switch plunger can be transferred from the second switch position to the first switch position and the motor thereby put into operation again.

The switch channel preferably extends as axial channel along the second axis so that it can be easily formed.

It is expedient for the axial bore to be connected to the pressure line via a compensation channel via which the switch plunger is acted upon at an active surface with pressure of the liquid in the pressure line, which active surface acts counter to an active surface of the switch plunger, via which the switch plunger is acted upon with pressure of the liquid in the pressure chamber. When the switch plunger is transferred from the first switch position to the second switch position and vice versa, the switch plunger is moved axially against the differential pressure of the liquid in the pressure chamber and in the pressure line. In practice, this proves advantageous for reliable functioning of the switch plunger.

For facilitated machining of the attachment, it may be provided that the compensation channel extends along or parallel to the first axis.

The pump preferably comprises a constructional unit, including the switch plunger and the electric switch element, in a form of a pressure switch installed in the axial bore. The switch plunger and the electric switch contact may be a component of a pre-assembled constructional unit, which, for quicker assembly on the pump head, can be pre-assembled and installed in the axial bore.

An advantageous embodiment of the pump in accordance with the invention is a crankshaft pump.

In a different preferred embodiment of the pump, it may be provided that the pump is a swashplate pump.

As mentioned at the outset, the invention also relates to a high-pressure cleaning appliance. A high-pressure cleaning appliance in accordance with the invention comprises at least one pump of the aforementioned kind.

The following description of preferred embodiments of the invention will serve, in conjunction with the drawings, to explain the invention in more detail. There are shown in:

Figure 1: a perspective illustration of a high-pressure cleaning appliance in accordance with the invention, which comprises a first preferred embodiment of a pump in accordance with the invention, at an angle from the front;

Figure 2: a side view of a pump head of the pump of the high-pressure cleaning appliance from Figure 1;

Figure 3: a sectional view along line 3-3 in Figure 2;

Figure 4: a sectional view along line 4-4 in Figure 3; and

Figure 5: a sectional view of a pump head of a second preferred embodiment of a pump in accordance with the invention in a way corresponding to Figure 3.

Figure 1 shows in a perspective illustration at an angle from the front a preferred embodiment of a high-pressure cleaning appliance denoted in its entirety by reference numeral 10. The high-pressure cleaning appliance is configured as "tubular frame apparatus" and comprises a motor pump unit 12. The motor pump unit 12 comprises a motor 13 and a pump 14 flanged thereon for driving. In this case, the pump 14 is configured as crankshaft pump and comprises a pump block 15 connected to the motor 13 and a pump head 16 placed on the pump block 15.

The pump head 16 can be supplied with liquid to be pressurized, in particular, water, via a pump inlet 17. Connected to a delivery line 18 of the pump head 16 forming a high-pressure connection is a fluid line, in this case, in the form of a high-pressure hose 19, a section of which is shown. Connected to the high-pressure hose 19 at the end facing away from the pump head 16 is a high-pressure pistol 20, the pressure nozzle 21 of which can be selectively opened and closed by a user.

The high-pressure cleaning appliance 10 comprises an electric device 22 which is configured as switch device and is connected to the motor 13 via an electric connection line 23. The electric device 22 is connected via a further electric connection line (partially illustrated) 24 to a pressure switch 25 which is connected to the pump head 16. The pressure switch 25 will be discussed in more detail hereinbelow.

As will be clear from Figures 2 to 4, the pump head 16 has a compact, flat structure and comprises a main body 26 in which bores are made to form fluid lines and fluid channels. Starting from the pump inlet 17, a suction line 27, which opens via three inlet valves 28 into one pump chamber 29 in each case, is formed in the main body. Liquid to be pressurized can be compressed by means of pistons 30 in the pump chambers 29. The liquid is conducted via outlet valves 31 into a pressure line 32 parallel to the suction line 27. The delivery line 18 forming the high-pressure connection protrudes from the side of the pressure line 32. A bypass line 33 connects the pressure line 32 to the suction line 27 from the branch-off of the delivery line 18 to immediately behind the pump inlet 17.

The pressure line 32 comprises a first pressure line section 321 in which the outlet valves 31 are arranged and which defines the below-mentioned axis 50 of the pressure line 32, and a second pressure line section 322 from which the bypass line 33 and the delivery line 18 branch off.

The compact flat structure of the pump head 16 is achieved by the pump chamber 29, the pressure line 32 and the bypass line 33 being arranged in a common plane, the pump plane, which runs in the drawing plane in Figure 3. The bypass line 33 is aligned transversely to the pressure line 32 and transversely to the delivery line 18. The delivery line 18 and the bypass line 33 span a further plane, a second pump plane, which runs in the drawing plane in Figure 4. This promotes the compact structure of the pump head 16.

From the side opposite the bypass line 33, a piston 34 of an overflow valve 35 enters the pressure line section 322 of the pressure line 32. Held at the end on the piston 34 is a, in this case, spherical, valve body 36 which can seal and release a valve seat 37 at the start of the bypass line 33. The piston 34 is mounted in an insert 38 for displacement against the force of an elastic resetting element in the form of a spring 39. The piston 34 is configured as a stepped piston which delimits a pressure chamber 40 in a spaced manner.

The pressure chamber 40 is configured as a ring chamber and is in fluid connection with the delivery line 18 via a pressure channel 41. (Figure 4, in which the connection of the pressure chamber 40 and the pressure channel 41 is not shown.) Furthermore, a check valve 42 is installed in the delivery line 18. The check valve 42 can sealingly cover a valve seat 43 which, in relation to the direction of flow of the conducted liquid, is arranged before the connection of the pressure channel 41 to the delivery line 18.

When the pressure nozzle 21 of the high-pressure pistol 20 is closed, the check valve 42 seals off the delivery line 18. The overpressure remaining in the high-pressure hose 19 forms a pressure surge through the pressure channel 41 into the pressure chamber 40, which acts upon the piston 34. The piston 34 is displaced in order to lift the valve body 36 off the valve seat 37 so that the bypass line 33 is released. The liquid is circulated by the pump 14 in order to reduce the mechanical load between the suction line 27 and the pressure line 32 via the bypass line 33.

Conversely, the bypass line 33 is closed when the pressure nozzle 21 is released so that the piston 34 is moved back into its initial position again and, furthermore, opens the check valve 42.

In addition, the pump 14 comprises, as mentioned, the pressure switch 25, only a section of which is shown in Figure 3. The pressure switch 25 is installed in an attachment 44 formed on the main body 26.

In order to achieve a compact structure of the pump head 16, the attachment 44 is arranged in the pump plane defined by the pressure line 32 and the bypass line 33 and comprises two attachment sections 45 and 46. The attachment sections 45 and 46 are, in this case, configured as bodies, each with a cylindrical or substantially cylindrical outer contour, whereby they define a first axis 47 and a second axis 48, respectively. The outer contours of the attachment sections 45 and 46 are represented in their extension by dashed lines on the right in Figures 3 and 5.

The attachment sections 45 and 46 intersect each other, and their axes 47 and 48 intersect at a point of intersection 49 arranged outside of the pressure line 32 and the pressure chamber 40. The angle of intersection between the axes 47 and 48 is, in this case, approximately 20°. As a result, on the one hand, the attachment 44 has a compact configuration using a relatively small amount of material, and, on the other hand, the attachment sections 45 and 46 can be easily recognized and the position of the axes 47 and 48, respectively, detected.

In order to achieve a compact structure of the pump head 16, the attachment 44 is formed on the main body 26 on that side along which the bypass line 33 extends, and the overflow valve 35 is arranged between the attachment 44 and the pressure line section 321, in which the outlet valves 31 are arranged.

The first axis 47 defined by the first attachment section 45 is aligned parallel to an axis 50 defined by the pressure line 32, in particular, of the pressure line section 321 and is offset somewhat from the axis 50 in the direction of the pressure chamber 40. The first axis 47 traverses the pressure line section 322 at its side opposite the bypass line 33. The first attachment section 45 is therefore formed on the main body 26 such that the first axis 47 intersects the pressure line 32 at the pressure line section 322.

The second attachment section 46 is formed on the main body 26 such that the second axis 48 runs through the pressure chamber 40 and intersects it. Formed in the second attachment section 46 along the axis 48 is an axial bore 51 in which the pressure switch 25 is partially installed. For this purpose, it has a sealing insert 52 and a switch plunger 53 axially movable relative thereto. The switch plunger 53 is supported via an elastic resetting element in the form of a spring 54 on the insert 52 through which it passes, so that with its end facing away from the pressure chamber 40 it can actuate an electric switch element 55 of the pressure switch 25.

Adjoining the axial bore 51 is an axial switch channel 56 via which the bore 51 is in fluid connection with the pressure chamber 40. A compensation channel 57 is formed in the first attachment section 45 parallel to the first axis 47. Via the compensation channel 57, the pressure line section 322 of the pressure line 32 is in fluid connection with the axial bore 51.

The compensation channel 57 opens into an annular space of the bore 51, which surrounds the insert 52 and is in fluid connection with the space of the bore 51 accommodating the switch plunger 53. The pressure in the pressure chamber 40 and the pressure in the pressure line 32 thereby act on active surfaces 58 and 59, respectively, of the switch plunger 53, which face away from each other.

The switch channel 56 and the compensation channel 57 ensure that upon closing the pressure nozzle 21, after opening the overflow valve 35, the switch plunger 53 is axially displaced against the force of the spring 54 and the differential pressure of the pressure chamber 40 and the pressure line 32, in order to actuate the switch element 55. This results in a switch pulse, which is transferred by the pressure switch 25 to the electric device 22 in order to switch off the motor 13. When the pressure nozzle 21 is opened, the pressure in the pressure chamber 40 drops, and owing to the differential pressure of the pressure line 32 and the pressure chamber 40 and to the supporting force of the spring 54, the switch plunger 53 is displaced back into the original position with actuation of the switch element 55. The electric device 22 thereby receives a start pulse to switch on the motor 13 so that cleaning liquid can be conveyed again. A pump head 60 shown in a sectional illustration in Figure 5 in a way corresponding to Figure 3 can be combined with the pump block 15 to form a second preferred embodiment of a pump in accordance with the invention.

This pump may also be used in the high-pressure cleaning appliance 10. The same reference numerals are used for identical features of the pump heads 16 and 60. The illustration in accordance with Figure 4 is at the same time a sectional view along line 4-4 in Figure 5.

With respect to its structure, the pump head 60 corresponds substantially to the pump head 16. The pump head 60 differs from the pump head 16 in that no pressure switch 25 is present, but instead a pressure relief valve 61, and in that this is installed on the attachment 44 machined in a different way. The attachment 44 in the pump head 60 is outwardly substantially identical to the attachment 44 in the pump head 16. Excluded from this is a projection 62 (Figure 3) which is still present on the second attachment section 46 at the end facing away from the pressure chamber 40, owing to its machining, but the projection 62 is missing in the pump head 60 owing to its machining of the attachment 44.

In the attachment 44 of the pump head 60, the first attachment 45 has an axial bore 63 in which the pressure relief valve 61 is installed. The pressure relief valve 61 comprises a closure element 64 which closes the bore 63 at the end and on which a valve body 65 of the pressure relief valve 61 is supported by means of an elastic resetting element in the form of a spring 66. The bore 63 is connected via an axial overpressure channel 67 to the pressure line section 322 of the pressure line 32 so that the pressure in the pressure line 32 acts upon the valve body 65.

The pressure relief valve 61 is a safety valve. When the pressure in the pressure line 32 exceeds a maximum permissible value, the valve body 65 is displaced against the force of the spring 66. The spring 66 has a buffer effect so that the sealing closure element 64 is not pressed out of its seat immediately. This does, however, happen when the permissible pressure is exceeded to a high extent or when the overpressure lasts for some considerable time. In both cases, the pressure relief valve 61 is pressed out of the bore 63, and liquid can exit from the pump head 60 via the overpressure channel 67 and the bore 63.

The attachment 44 is formed on the main body 26 in both pump heads 16 and 60 and, in each case, comprises the attachment sections 45 and 46, which define the axes 47 and 48. This allows, in a constructionally simple way, a common blank to be provided for the main body 26 for manufacture of both the pump head 16 and the pump head 60. Depending on whether a variant of the pump with pump head 16 or a variant of the pump with pump head 60 is manufactured, the axial bore 51, the switch channel 56 and the compensation channel 57, on the one hand, or the axial bore 63 and the overpressure channel 67, on the other hand, can be formed in the attachment 44 and the main body 26. In particular, it is not necessary to keep different blanks available for manufacture of the main bodies 26 of the pump heads 16 and 60. This allows manufacturing costs, for example, for tools, or storage costs to be reduced.

The manufacturing costs are also kept low by the inclined alignment of the attachment sections 45 and 46 relative to each other. The attachment 44 has a compact structure, which can be achieved with only a small amount of material. In addition, the amount of material to be removed when machining the attachment 44 for manufacture of the pump heads 16 or 60 is low, which, in turn, has an advantageous effect on the manufacturing costs. The providing of the attachment 44 with the attachment sections 45 and 46 also facilitates manufacture of the pump heads 16 and 60. Owing to the cylindrical outer contour in each case, a person performing the machining can easily determine the axes 47 and 48. This makes it easier for him to form the bores 51 and 63 and the channels 56, 57 and 67, if required, in the attachment sections 45 and 46.

Claims (17)

A pump for a high-pressure cleaner (10) for transporting a cleaning fluid, the pump (14) having a pump head (16) comprising a base body (26) in which a suction line (27) and a pressure line (32) are formed. which is connected thereto via at least one pump chamber (29), characterized in that a bypass line (33) connecting the pressure line (32) to the suction line (27) is arranged transverse to the pressure line. (32) defining a pump plane therewith and a delivery line (18) connected to the pressure line (32) for connecting an external fluid line, the pump head (16) having an overflow valve (35) arranged on the bypass line (33), and if the valve body (36) is connected to a piston (34) which, from the side opposite the bypass line (33), enters the pressure line (32), sectionally limits a pressure chamber (40) which is in communication with the the delivery conduit (18) via a pressure channel (41) and as dependent on liquid the pressure in the pressure chamber (40) moves the valve body (36) to open and close the bypass line (33), where on the base body (26) is formed a shoulder (44) having a first shoulder section (45) defining a a first axis (47) intersecting the pressure line (32) and a second shoulder section (46) defining a second axis (48) intersecting the pressure chamber (40), the first axis (47) and the second axis (48) ) intersect at an intersection (49) which is outside the pressure line (32) and the pressure chamber (40). Pump according to claim 1, characterized in that the angle of intersection between the first axis (47) and the second axis (48) is less than 90 °, preferably less than 60 °, even more preferably less than 30 °. Pump according to claim 2, characterized in that the cutting angle is approx. 20 °. Pump according to one of the preceding claims, characterized in that the first impact section (45) and the second impact section (46) define the first axis (47) and the second axis (48), respectively, based on their external contour. Pump according to claim 4, characterized in that the first impact section (45) and the second impact section (46) are intersection sections (45, 46) which intersect and intersect, in particular, with a cylindrical or substantially cylindrical outer contour. . Pump according to one of the preceding claims, characterized in that at least one of the impact portions (45, 46) is arranged in the pump plane, in particular that both impact portions (45, 46) are arranged in the pump plane. Pump according to one of the preceding claims, characterized in that the shoulder (44) is formed on one side of the base body (26), along this bypass line (33) and that the overcurrent valve (35) is arranged between the shoulder (44). ) and a pressure line section (321) of the pressure line (32), in which at least one output valve (31) is provided for sealing the at least one pump chamber (29) relative to the pressure line (32). Pump according to one of the preceding claims, characterized in that the delivery line (18) is oriented transversely of the pressure line (32) and / or that the delivery line (18) and the bypass line (33) define another pump plane which is oriented perpendicularly on the pump plane. Pump according to one of the preceding claims, characterized in that the first impact section (45) has an axial bore (63) along the first axis (47) into which an overpressure valve (61) is inserted and that the bore ( 63) is connected to the pressure line (32) via an overpressure channel (67). Pump according to claim 9, characterized in that the overpressure duct (67) as the axial duct extends along the first axis (47) and / or that the overpressure duct (67) is connected to a section of the pressure line (32), in which section the valve body (36) of the overflow valve (35) is disposed and from which the bypass line (33) branches. Pump according to one of claims 1 to 8, characterized in that the second impact section (46) has an axial bore (51) along the second axis (48) into which a shock coupling element (53) is inserted and the bore (51) is connected via a coupling channel (56) to the pressure chamber (40), where, depending on the pressure in the pressure chamber (40), the shock coupling element (53) can be moved axially from a first coupling position to a second coupling position and vice versa for activating an electrical coupling element ( 55). Pump according to claim 11, characterized in that the coupling duct (56) as the axial duct extends along the second axis (48). Pump according to claim 11 or 12, characterized in that the axial bore (51) is connected via a compensating channel (57) to the pressure line (32), through which the compensating channel the coupling shock element (53) is actuated by a liquid pressure in the pressure line (32) of a working surface (59), which working surface (59) acts against a working surface (58) of the coupling shock element (53), via which the working surface of the coupling shock element (53) is influenced by the fluid pressure in the pressure chamber (40). Pump according to claim 13, characterized in that the compensating channel (57) runs along or parallel to the first axis (47). Pump according to one of claims 11 to 14, characterized in that the pump (14) has a component unit comprising the coupling shock element (53) and the electrical coupling element (55) in the form of a pressure contact (25) inserted in the axial bore (51). Pump according to one of the preceding claims, characterized in that the pump (14) is a crankshaft pump. A high-pressure cleaner comprising at least one pump (14) according to one of the preceding claims.