JPH0319680Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a lubricant supply pump, and more particularly, to a lubricant supply pump that supplies lubricant such as grease to lubricated parts of working machines and the like.

(Prior Art) A specific example of a conventional lubricant supply pump is the device described in Japanese Patent Publication No. 60-44556. The above device is schematically shown in FIG. 4, and as shown in the figure, this device consists of a pump body 51 and a lubricant discharge mechanism attached to the right side of the pump body 51. 52, and a tank 53 attached to the upper part of the pump body 51. The pump main body 51
A first communication hole 54 serving as a pump chamber is formed from the discharge mechanism section 52 side, and a suction passage 55 communicating with the first communication hole 54 is formed from the upper end surface of the pump body 51. ing. This suction passage 5
The tank 53 is screwed onto the top of the tank 5. A check valve 56 is provided at the left end of the first communication hole 54 in the figure.
6 is biased toward the discharge mechanism section 52 by a spring 58 disposed between the end plate 57 and the end plate 57 .
The first communication hole 54 is provided at a lower position of the first communication hole 54 in accordance with the reciprocating movement of the check valve 56.
A second communication hole 60 having an opening 59 that can be opened and closed in communication with the pump body 51 is formed therein, and a discharge passage 61 communicating with the second communication hole 60 is formed at the lower end of the pump body 51. has been done. On the other hand, a reciprocating plunger 62 is inserted into the first communication hole 54 from the discharge mechanism section 52 side.
Inside the discharge mechanism section 52, the plunger 62 is provided.
This pressure receiving plate 6
3 and the pump body 51, and an inflow port (not shown) for a working fluid such as compressed air is provided on the surface of the pressure receiving plate 63 opposite to the spring 64. A pressure chamber 65 having a pressure chamber 65 is provided respectively. By introducing compressed air or the like into the pressure chamber 65, the plunger 62 moves forward within the first communication hole 54 beyond the opening position of the suction passage 55 to a position close to the check valve 56, On the other hand, when the action of the compressed air is released, the plunger 62 moves backward from the opening position of the suction passage 55 due to the spring force of the spring 64.

According to the reciprocating movement of the plunger 62 as described above, the space volume of the first communication hole 54 between the tip of the plunger 62 and the check valve 56 changes, and a so-called pumping action occurs, causing the inside of the tank 53 to change. The lubricant is sucked in and extruded into the second communication hole 60 through the check valve 56 successively, and the lubricant is discharged from the discharge passage 61 in an amount corresponding to the number of reciprocations of the plunger 62.

As shown in the figure, the tank 53 in the above device has a cylindrical configuration with a bottom, and its side wall 66 has a bellows structure that can be expanded and contracted, and the internal volume changes depending on the remaining amount of lubricant inside. As the amount of lubricant changes, no negative pressure space is created inside, and the lubricant suction force described above when the pump operates effectively acts even when the remaining amount changes, and the lubricant is sucked.・It is designed so that the discharge can continue. Note that 67 is a removable cover that covers the tank 53.

As described above, in the tank 53 which is configured in a sealed manner except for the lubricant outlet portion screwed into the suction passage 55 of the pump body 51, no space is created inside as the remaining amount of lubricant decreases. As in, the side wall 66
It is formed of a bellows structure that can be expanded and contracted. However, if the remaining amount of lubricant decreases below the minimum capacity when the folds of the bellows structure are in close contact, a negative pressure space will be created inside, and the suction of the pump action will occur. The force ceased to act, so it was necessary to replace the lubricant while leaving the lubricant in the tank 53. In addition, in order to ensure the quantification of the discharge amount in one reciprocating motion of the plunger 62, the tank 53 is designed such that the shape restoring force of the tank 53, which has been shrunk and deformed, does not affect the suction force as much as possible. is usually made of soft material such as soft resin.
However, even if the material is soft like this, the shape restoring force due to its elasticity will accumulate as the amount of deformation increases and if there are many folds, this will accumulate, so it is especially important to reduce the frequency of replacing the tank 53. When using a tank with a large shape and therefore a large number of folds in order to reduce the amount of lubricant, the shape restoring force cannot be ignored when the remaining amount decreases, and the suction force of the lubricant due to the reciprocating movement of the plunger 62 increases as described above. It was also reduced by the restoring force, making it impossible to maintain quantification of the discharge amount. Furthermore, if the tank 53 is made of a softer material in order to solve the problem of shape restoring force caused by the deformation of the tank 53, the shrinkage deformation will occur in an irregular manner, and the lubricant will remain in a locally uneven state. In some cases, the lubricant may not be supplied from the tank 53 midway through the process.

As a countermeasure for the above, it is possible to adopt, for example, the structure described in Japanese Patent Application Laid-open No. 159500/1983. This is a system in which a pressing member is attached to the bottom of the tank, and a spring is interposed between the pressing member and the cover to press the tank bottom. A raised part for pushing out the tank when it decreases, and a guide part that slides against the inner circumferential surface of the cover to prevent the tank from falling down are integrally formed.

(Problem to be solved by the invention) However, in the above conventional example, although it is possible to use most of the lubricant in the tank and prevent the tank from distorting, it is possible to use a separate member with a special structure called a pressing member. Since it is necessary to use the above, the structure becomes complicated and the cost increases.

This invention was made to solve the above-mentioned conventional problems, and its purpose is to use the lubricant as effectively as possible in a tank whose side wall has a bellows structure, and to reduce the remaining amount. A lubricant that can maintain a substantially constant discharge amount even when the tank is made of soft material, prevent the tank from shrinking and deform, and simplify its structure. The purpose is to provide a feed pump.

(Means for Solving the Problems) Therefore, in the lubricant supply pump of this invention, the lubricant in the bottomed cylindrical tank 3 is supplied to the suction passage 5 of the pump body 1 having the suction passage 5 and the discharge passage 10. Connect the outlet 6 and transfer the lubricant in the tank 3 to the suction path 5.
This is a lubricant supply pump comprising a lubricant discharge mechanism 2 for discharging the lubricant into a discharge passage 10, in which the side wall 25 of the tank 3 is configured with an elastic bellows structure, and the bottom part of the tank 3 is configured with a bellows structure. 26 is provided with a recess 27 that is recessed inward, and the cover 28 that covers the tank 3 is provided with a recess 35 that is recessed in the opposite direction at a position opposite to the recess 27. A biasing means 29 for biasing the bottom portion 26 of No. 3 in the direction of the suction passage 5 is connected to both the recesses 27,
35, and the biasing means 29 is guided in the biasing direction by the inner walls of both the recesses 27, 35.

(Function) In the lubricant supply pump configured as described above, the bellows-shaped side wall 2
5 performs a shrinking deformation to reduce the internal volume, a recess 27 is provided in the bottom 26 connected to the side wall 25, and the bottom 26 is urged toward the suction passage 5 by the urging means 29. There is. Said biasing means 2
9 provides a guiding action such that the bottom portion 26 moves toward the suction passage 5 along the axis of the tank 3, and in this state, the side wall 25 shrinks and deforms, and each fold is brought into close contact. If it gets old, this side wall 2
The recessed portion 27 is in a state of being recessed into the inside of the portion 5. Therefore, the minimum volume is reduced by the volume of the recess 27 compared to the conventional case, and the lubricant can be effectively discharged by that amount. Further, the force necessary for shrinking and deforming the tank 3 is also applied by the urging force of the urging means 29, so even if the remaining amount of lubricant in the tank 3 decreases, the suction force in the lubricant discharging mechanism 2 is maintained. It continues to act as a suction force for the lubricant, and it is possible to maintain a substantially constant discharge amount.

Further, since the biasing means 29 is guided in the biasing direction by the inner walls of both the recesses 27 and 35, the tank 3
Even if the material of the tank 3 is soft, the tank 3 can be prevented from being distorted.

(Example) Next, a specific example of the lubricant supply pump of this invention will be described in detail with reference to the drawings.

FIG. 1 is a sectional view of a lubricant supply pump according to an embodiment of the present invention, FIG. 2 is a sectional view taken at - in FIG. 1, and FIG. 3 is a side view of FIG. 1. In FIG. 1, a pump body 1 is provided with a lubricant discharge mechanism 2 on the right side in the figure, and a bottomed cylindrical tank 3 made of soft resin on the top. A communication hole 4 serving as a pump chamber is bored horizontally in the pump body 1 in the figure. Then, from the top surface of the pump body 1 to the communication hole 4
A suction passage 5 leading to the tank 3 is vertically bored, and a lubricant outlet 6 of the tank 3 is screwed into an upper threaded portion of the suction passage 5. Also, the communication hole 4
A check valve chamber 7 is provided at the end opposite to the attachment portion of the lubricant discharge mechanism 2, and a spring 8 is applied to the end surface of the communication hole 4 in the check valve chamber 7. A check valve 9 is disposed that is biased into contact. A discharge passage 10 communicating with the check valve chamber 7 is bored at the lower end of the pump body 1.
The lower surface through which this discharge passage 10 opens is adapted to connect this device by means of a nut 12 to a nipple 11 which is screwed onto the device to which the lubricant supply pump is attached. A plunger 13 is inserted into the communication hole 4 from the lubricant discharge mechanism 2 side so as to be slidable in the axial direction within the communication hole 4 . An O-ring 14 is provided around the plunger 13 at the opening end of the communication hole 4 of the pump body 1 to provide a shaft seal.

Inside the lubricant discharging mechanism 2, as shown in FIG.
are arranged as shown in Figure 3. The rotation of the DC motor 16 is transmitted by a gear transmission mechanism 17 as rotation of a crank 19 attached to the output shaft 18 about the output shaft 18 . This crank 19 has a connecting member 20 as shown in FIG.
One end side of is connected by a pin 21,
The end of the plunger 13 is pin-coupled to the other end of the connecting member 20. Therefore, when the output shaft 18 rotates, this rotational movement is converted into a reciprocating movement of the plunger 13 via the connecting member 20. The plunger 13 in FIG. 1 shows the forward movement start position, and as shown in the figure, the tip of the plunger 13 is positioned slightly closer to the lubricant discharge mechanism 2 than the center of the suction passage 5.
At the forward movement end position, the tip of the plunger 13 crosses the opening of the suction passage 5 to the communication hole 4 and approaches the check valve 9. Due to the reciprocating movement of the plunger 13 and the check valve 9 at the end of the communication hole 4, a so-called pumping action occurs in the space of the communication hole 4, and when the plunger 13 moves back, water is removed from the suction passage 5. The lubricant is sucked into the discharge passage 10 through the check valve 9 during forward movement.
The sucked lubricant is then discharged to the side.

As shown in FIG. 1, the tank 3 screwed into the suction path 5 has a side wall 25 formed in a bellows structure. A recess 27 is formed in the bottom (upper part in the figure) 26.
A spring 29 serving as a biasing means is arranged between the tank and the cover 28 covering the tank. The lower end of the cover 28 is fitted into a groove provided in the upper end of the pump body 1. Therefore, due to the spring 29, the bottom part 26 of the tank is connected to the suction passage 5.
It is configured to be biased toward the side. The biasing force of the spring 29 is such that even when the spring 29 is at its maximum deflection (when the tank internal volume is at its maximum), the lubricant pushing force due to the spring force is the same as that of the spring 8 in the check valve chamber 7. The spring force of each spring 8, 29 is adjusted so that it is smaller than the outflow blocking force. Further, in FIG. 3, the lubricant discharging mechanism 2 is shown with the lid removed to show the internal structure. This is a circuit board with components attached. Further, the lid 31 is
As shown in FIG. 2, a snap spring 32 provides an attachment structure that allows easy attachment and detachment. Further, in FIG. 2, reference numeral 33 denotes an injection port for replenishing lubricant into the tank 3 from the outside, and communicates with the opening position of the suction path 5 to the communication hole 4. A blind plug 34 is normally attached to the injection port 33.

The operation of the lubricant supply pump having the above configuration will be described next. When the DC motor 16 is rotated, this rotational motion is transmitted as a reciprocating motion of the plunger 13 as described above. This plunger 13
During the return movement, the space volume of the communication hole 4 whose one end is sealed by the check valve 9 increases, and negative pressure is generated there. When the tip of the plunger 13 retreats backward from the opening of the suction passage 5 to the communication hole 4,
The negative pressure acts as a suction force for the lubricant in the tank 3, and the lubricant is sucked out into the suction path 5 and the communication hole 4. Thereafter, when the plunger 13 moves forward, when the tip of the plunger 13 advances beyond the opening of the suction passage 5 to the communication hole 4, the lubricant sealed between the check valve 9 and the opening becomes As the tip of the plunger 13 moves forward, the check valve 9 opens and is pushed out from the check valve chamber 7 into the discharge path 10. Due to such reciprocating motion of the plunger 13, the lubricant in the tank 3 is sequentially discharged from the discharge passage 10. With this supply operation, the lubricant in the tank 3 decreases, and at this time, the bellows-shaped side wall 25 shrinks and deforms so that the internal volume matches the remaining capacity, creating negative pressure in the tank 3. To avoid creating a space under pressure,
Therefore, the suction force generated by the negative pressure when the plunger 13 moves back as described above continues to act effectively even when the amount of lubricant decreases.

In the embodiment described above, the bottom portion 26 of the tank 3 is urged toward the suction passage 5 by the spring 29. In the conventional device, when the shrinkage deformation of the tank increases, the shape recovery force due to the elasticity of the side wall cannot be ignored and the suction force decreases. However, due to the action of the spring 29, in the above embodiment, In addition to the suction force due to the negative pressure generated when the plunger 13 moves back, the spring force also acts as a pushing force from the lubricant tank 3, so that the communication hole 4 generated when the plunger 13 moves back
This makes it possible to always fill up the space volume of the lubricant even when the remaining amount of lubricant decreases, and it is possible to keep the discharge amount per plunger 13 substantially constant. Further, in the above embodiment, a recess 27 is provided in the bottom 26 of the tank 3. As a result, the tank 3 is used until the bottom 26 of the tank 3 reaches the position shown by the two-dot chain line in FIG. be able to. Therefore, in the past, the lubricant could not be used beyond the depth when the folds of the bellows structure of the side wall were in close contact, but in the above embodiment, most of the lubricant inside the tank 3 can be used. Therefore, the agent can be used effectively. Furthermore, in the above embodiment, the upper end side of the spring 29 that biases the bottom part 26 is connected to the cover 2 as shown in FIG.
8, and the lower end of the spring 29 is fitted into a recess 27 provided in the bottom 26, which is disposed substantially coaxially with the recess 35. As a result, the spring 29
For example, if the side wall material of the tank 3 is soft,
In addition, even if the initial volume is large and the depth is large, it is possible to prevent the lubricant from collapsing, suppressing irregular shrinkage deformation, and ensuring a stable supply of lubricant. can be ensured.

Note that the above-mentioned embodiments do not limit the contents of this invention, and various changes can be made within the scope of this invention. For example, the structure of the lubricant discharge mechanism may be changed to the above-mentioned plunger operation method using fluid pressure, etc. This idea can also be applied to other things.

(Effects of the invention) As described above, in the lubricant supply pump of this invention, even when the remaining amount of lubricant in the tank is low, the remaining lubricant can be used effectively. Also, it is possible to prevent the tank from becoming distorted. Moreover, since the structure is simply a pair of recesses formed in the bottom of the tank and the cover,
Its configuration is much simpler than before, and it can be manufactured at low cost.

[Brief explanation of the drawing]

Figure 1 is a sectional view of one embodiment of the lubricant supply pump of this invention, and Figure 2 is a -
3 is a side view of the device shown in FIG. 1;
The figure is a schematic cross-sectional view of a conventional device. 1...Pump body, 2...Lubricant discharge mechanism, 3
... Tank, 5 ... Suction path, 6 ... Lubricant outlet,
10...Discharge path, 25...Side wall, 26...Bottom,
27... recess, 28... cover, 29... spring (biasing means), 35... recess.

Claims (1)

[Scope of utility model registration request] Pump body 1 having a suction passage 5 and a discharge passage 10
A lubricant outlet 6 of a bottomed cylindrical tank 3 is connected to the suction passage 5 of the lubricant discharge mechanism 2 for discharging the lubricant in the tank 3 from the suction passage 5 to the discharge passage 10. A lubricant supply pump comprising: a side wall 25 of the tank 3 having an elastic bellows structure; and a bottom 26 of the tank 3;
A recess 27 recessed inwardly is provided in the tank 3, and a recess 35 recessed in the opposite direction to the recess 27 is provided in the cover 28 that covers the tank 3. A biasing means 29 for biasing the bottom portion 26 in the direction of the suction passage 5 is arranged in both the recesses 27 and 35, and
A lubricant supply pump characterized in that the urging means 29 is guided in the urging direction by an inner wall of the lubricant supply pump.